| Message ID | 20250502-qpic-snand-8bit-ecc-v1-2-95f3cd08bbc5@gmail.com |
|---|---|
| State | New |
| Headers | show |
| Series | spi: spi-qpic-snand: enable 8 bits ECC strength support | expand |
On 5/3/2025 1:01 AM, Gabor Juhos wrote: > Even though the hardware supports 8 bits ECC strength, but that is not > handled in the driver yet. This change adds the missing bits in order > to allow using the driver with chips which require 8 bits ECC strength. > > No functional changes intended with regard to the existing 4 bits ECC > strength support. > > Tested on an IPQ9574 platform using a GigaDevice GD5F2GM7REYIG chip. > > Signed-off-by: Gabor Juhos <j4g8y7@gmail.com> > --- > mtdtest results: > > # dmesg | grep nand > [ 0.678143] spi-nand spi0.0: GigaDevice SPI NAND was found. > [ 0.687393] spi-nand spi0.0: 256 MiB, block size: 128 KiB, page size: 2048, OOB size: 128 > # cat /proc/mtd > dev: size erasesize name > mtd0: 10000000 00020000 "spi0.0" > # insmod mtd_test > # insmod mtd_speedtest dev=0 > [ 63.128425] > [ 63.128452] ================================================= > [ 63.128979] mtd_speedtest: MTD device: 0 > [ 63.134622] mtd_speedtest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 > [ 63.139561] mtd_test: scanning for bad eraseblocks > [ 63.756447] mtd_test: scanned 2048 eraseblocks, 0 are bad > [ 71.085514] mtd_speedtest: testing eraseblock write speed > [ 202.745977] mtd_speedtest: eraseblock write speed is 1991 KiB/s > [ 202.746022] mtd_speedtest: testing eraseblock read speed > [ 284.104591] mtd_speedtest: eraseblock read speed is 3222 KiB/s > [ 291.405533] mtd_speedtest: testing page write speed > [ 422.516341] mtd_speedtest: page write speed is 1999 KiB/s > [ 422.516384] mtd_speedtest: testing page read speed > [ 504.144630] mtd_speedtest: page read speed is 3211 KiB/s > [ 511.476726] mtd_speedtest: testing 2 page write speed > [ 643.114443] mtd_speedtest: 2 page write speed is 1991 KiB/s > [ 643.114485] mtd_speedtest: testing 2 page read speed > [ 724.434752] mtd_speedtest: 2 page read speed is 3223 KiB/s > [ 724.434796] mtd_speedtest: Testing erase speed > [ 731.792729] mtd_speedtest: erase speed is 35648 KiB/s > [ 731.792772] mtd_speedtest: Testing 2x multi-block erase speed > [ 739.162513] mtd_speedtest: 2x multi-block erase speed is 35589 KiB/s > [ 739.162558] mtd_speedtest: Testing 4x multi-block erase speed > [ 746.486241] mtd_speedtest: 4x multi-block erase speed is 35820 KiB/s > [ 746.486287] mtd_speedtest: Testing 8x multi-block erase speed > [ 753.789683] mtd_speedtest: 8x multi-block erase speed is 35919 KiB/s > [ 753.789728] mtd_speedtest: Testing 16x multi-block erase speed > [ 761.093075] mtd_speedtest: 16x multi-block erase speed is 35920 KiB/s > [ 761.093120] mtd_speedtest: Testing 32x multi-block erase speed > [ 768.396145] mtd_speedtest: 32x multi-block erase speed is 35922 KiB/s > [ 768.396222] mtd_speedtest: Testing 64x multi-block erase speed > [ 775.699819] mtd_speedtest: 64x multi-block erase speed is 35918 KiB/s > [ 775.699863] mtd_speedtest: finished > [ 775.705259] ================================================= > # insmod mtd_readtest dev=0 > [ 919.060671] > [ 919.060699] ================================================= > [ 919.061226] mtd_readtest: MTD device: 0 > [ 919.066957] mtd_readtest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 > [ 919.070556] mtd_test: scanning for bad eraseblocks > [ 919.086016] mtd_test: scanned 2048 eraseblocks, 0 are bad > [ 919.089465] mtd_readtest: testing page read > [ 1090.778227] mtd_readtest: finished > [ 1090.778286] ================================================= > # insmod mtd_pagetest dev=0 > [ 1216.297313] > [ 1216.297341] ================================================= > [ 1216.297867] mtd_pagetest: MTD device: 0 > [ 1216.303509] mtd_pagetest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 > [ 1216.307213] mtd_test: scanning for bad eraseblocks > [ 1216.322680] mtd_test: scanned 2048 eraseblocks, 0 are bad > [ 1216.326077] mtd_pagetest: erasing whole device > [ 1223.694968] mtd_pagetest: erased 2048 eraseblocks > [ 1223.695009] mtd_pagetest: writing whole device > [ 1223.763930] mtd_pagetest: written up to eraseblock 0 > [ 1240.268942] mtd_pagetest: written up to eraseblock 256 > [ 1256.641498] mtd_pagetest: written up to eraseblock 512 > [ 1273.139048] mtd_pagetest: written up to eraseblock 768 > [ 1289.718929] mtd_pagetest: written up to eraseblock 1024 > [ 1306.244553] mtd_pagetest: written up to eraseblock 1280 > [ 1322.939723] mtd_pagetest: written up to eraseblock 1536 > [ 1339.246937] mtd_pagetest: written up to eraseblock 1792 > [ 1355.613729] mtd_pagetest: written 2048 eraseblocks > [ 1355.613770] mtd_pagetest: verifying all eraseblocks > [ 1355.854290] mtd_pagetest: verified up to eraseblock 0 > [ 1416.657733] mtd_pagetest: verified up to eraseblock 256 > [ 1477.384593] mtd_pagetest: verified up to eraseblock 512 > [ 1538.008142] mtd_pagetest: verified up to eraseblock 768 > [ 1599.080797] mtd_pagetest: verified up to eraseblock 1024 > [ 1660.775431] mtd_pagetest: verified up to eraseblock 1280 > [ 1722.177149] mtd_pagetest: verified up to eraseblock 1536 > [ 1783.090166] mtd_pagetest: verified up to eraseblock 1792 > [ 1844.450757] mtd_pagetest: verified 2048 eraseblocks > [ 1844.450798] mtd_pagetest: crosstest > [ 1844.455676] mtd_pagetest: reading page at 0x0 > [ 1844.458603] mtd_pagetest: reading page at 0xffff800 > [ 1844.463047] mtd_pagetest: reading page at 0x0 > [ 1844.467790] mtd_pagetest: verifying pages read at 0x0 match > [ 1844.471636] mtd_pagetest: crosstest ok > [ 1844.477062] mtd_pagetest: erasecrosstest > [ 1844.480833] mtd_pagetest: erasing block 0 > [ 1844.488498] mtd_pagetest: writing 1st page of block 0 > [ 1844.489821] mtd_pagetest: reading 1st page of block 0 > [ 1844.494475] mtd_pagetest: verifying 1st page of block 0 > [ 1844.498942] mtd_pagetest: erasing block 0 > [ 1844.507505] mtd_pagetest: writing 1st page of block 0 > [ 1844.509042] mtd_pagetest: erasing block 2047 > [ 1844.516725] mtd_pagetest: reading 1st page of block 0 > [ 1844.518087] mtd_pagetest: verifying 1st page of block 0 > [ 1844.522415] mtd_pagetest: erasecrosstest ok > [ 1844.527495] mtd_pagetest: erasetest > [ 1844.531613] mtd_pagetest: erasing block 0 > [ 1844.538671] mtd_pagetest: writing 1st page of block 0 > [ 1844.540249] mtd_pagetest: erasing block 0 > [ 1844.547869] mtd_pagetest: reading 1st page of block 0 > [ 1844.548927] mtd_pagetest: verifying 1st page of block 0 is all 0xff > [ 1844.553326] mtd_pagetest: erasetest ok > [ 1844.559440] mtd_pagetest: finished with 0 errors > [ 1844.563233] ================================================= > # insmod mtd_subpagetest dev=0 > [ 1942.429708] > [ 1942.429736] ================================================= > [ 1942.430262] mtd_subpagetest: MTD device: 0 > [ 1942.435905] mtd_subpagetest: MTD device size 268435456, eraseblock size 131072, page size 2048, subpage size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 > [ 1942.439994] mtd_test: scanning for bad eraseblocks > [ 1942.457111] mtd_test: scanned 2048 eraseblocks, 0 are bad > [ 1949.824564] mtd_subpagetest: writing whole device > [ 1949.826670] mtd_subpagetest: written up to eraseblock 0 > [ 1950.351816] mtd_subpagetest: written up to eraseblock 256 > [ 1950.875797] mtd_subpagetest: written up to eraseblock 512 > [ 1951.399912] mtd_subpagetest: written up to eraseblock 768 > [ 1951.923618] mtd_subpagetest: written up to eraseblock 1024 > [ 1952.447361] mtd_subpagetest: written up to eraseblock 1280 > [ 1952.970834] mtd_subpagetest: written up to eraseblock 1536 > [ 1953.494635] mtd_subpagetest: written up to eraseblock 1792 > [ 1954.016265] mtd_subpagetest: written 2048 eraseblocks > [ 1954.016294] mtd_subpagetest: verifying all eraseblocks > [ 1954.021617] mtd_subpagetest: verified up to eraseblock 0 > [ 1954.347458] mtd_subpagetest: verified up to eraseblock 256 > [ 1954.667446] mtd_subpagetest: verified up to eraseblock 512 > [ 1954.987343] mtd_subpagetest: verified up to eraseblock 768 > [ 1955.307385] mtd_subpagetest: verified up to eraseblock 1024 > [ 1955.627462] mtd_subpagetest: verified up to eraseblock 1280 > [ 1955.947277] mtd_subpagetest: verified up to eraseblock 1536 > [ 1956.266834] mtd_subpagetest: verified up to eraseblock 1792 > [ 1956.585581] mtd_subpagetest: verified 2048 eraseblocks > [ 1963.889308] mtd_subpagetest: verifying all eraseblocks for 0xff > [ 1963.930487] mtd_subpagetest: verified up to eraseblock 0 > [ 1974.592567] mtd_subpagetest: verified up to eraseblock 256 > [ 1985.180953] mtd_subpagetest: verified up to eraseblock 512 > [ 1995.805397] mtd_subpagetest: verified up to eraseblock 768 > [ 2006.348859] mtd_subpagetest: verified up to eraseblock 1024 > [ 2016.900530] mtd_subpagetest: verified up to eraseblock 1280 > [ 2027.447587] mtd_subpagetest: verified up to eraseblock 1536 > [ 2037.962383] mtd_subpagetest: verified up to eraseblock 1792 > [ 2048.587863] mtd_subpagetest: verified 2048 eraseblocks > [ 2048.587906] mtd_subpagetest: writing whole device > [ 2048.648174] mtd_subpagetest: written up to eraseblock 0 > [ 2062.643145] mtd_subpagetest: written up to eraseblock 256 > [ 2076.699015] mtd_subpagetest: written up to eraseblock 512 > [ 2091.004910] mtd_subpagetest: written up to eraseblock 768 > [ 2105.149879] mtd_subpagetest: written up to eraseblock 1024 > [ 2119.470691] mtd_subpagetest: written up to eraseblock 1280 > [ 2133.746861] mtd_subpagetest: written up to eraseblock 1536 > [ 2147.776477] mtd_subpagetest: written up to eraseblock 1792 > [ 2161.947734] mtd_subpagetest: written 2048 eraseblocks > [ 2161.947776] mtd_subpagetest: verifying all eraseblocks > [ 2161.986109] mtd_subpagetest: verified up to eraseblock 0 > [ 2170.818316] mtd_subpagetest: verified up to eraseblock 256 > [ 2179.596875] mtd_subpagetest: verified up to eraseblock 512 > [ 2188.405116] mtd_subpagetest: verified up to eraseblock 768 > [ 2197.188588] mtd_subpagetest: verified up to eraseblock 1024 > [ 2206.002204] mtd_subpagetest: verified up to eraseblock 1280 > [ 2214.784815] mtd_subpagetest: verified up to eraseblock 1536 > [ 2223.557141] mtd_subpagetest: verified up to eraseblock 1792 > [ 2232.472832] mtd_subpagetest: verified 2048 eraseblocks > [ 2239.818213] mtd_subpagetest: verifying all eraseblocks for 0xff > [ 2239.861404] mtd_subpagetest: verified up to eraseblock 0 > [ 2250.439035] mtd_subpagetest: verified up to eraseblock 256 > [ 2261.176485] mtd_subpagetest: verified up to eraseblock 512 > [ 2271.713183] mtd_subpagetest: verified up to eraseblock 768 > [ 2282.356892] mtd_subpagetest: verified up to eraseblock 1024 > [ 2292.891424] mtd_subpagetest: verified up to eraseblock 1280 > [ 2303.543110] mtd_subpagetest: verified up to eraseblock 1536 > [ 2314.116690] mtd_subpagetest: verified up to eraseblock 1792 > [ 2324.607804] mtd_subpagetest: verified 2048 eraseblocks > [ 2324.607846] mtd_subpagetest: finished with 0 errors > [ 2324.611859] ================================================= > # insmod mtd_oobtest dev=0 > [ 2336.159109] > [ 2336.159138] ================================================= > [ 2336.159664] mtd_oobtest: MTD device: 0 > [ 2336.165308] mtd_oobtest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 > [ 2336.169043] mtd_test: scanning for bad eraseblocks > [ 2336.184354] mtd_test: scanned 2048 eraseblocks, 0 are bad > [ 2336.187716] mtd_oobtest: test 1 of 5 > [ 2343.495966] mtd_oobtest: writing OOBs of whole device > [ 2343.496073] mtd_oobtest: written up to eraseblock 0 > [ 2343.516803] mtd_oobtest: written up to eraseblock 256 > [ 2343.533527] mtd_oobtest: written up to eraseblock 512 > [ 2343.549945] mtd_oobtest: written up to eraseblock 768 > [ 2343.563666] mtd_oobtest: written up to eraseblock 1024 > [ 2343.575186] mtd_oobtest: written up to eraseblock 1280 > [ 2343.584310] mtd_oobtest: written up to eraseblock 1536 > [ 2343.593011] mtd_oobtest: written up to eraseblock 1792 > [ 2343.600847] mtd_oobtest: written 2048 eraseblocks > [ 2343.600861] mtd_oobtest: verifying all eraseblocks > [ 2343.604542] mtd_oobtest: verified up to eraseblock 0 > [ 2343.616606] mtd_oobtest: verified up to eraseblock 256 > [ 2343.623992] mtd_oobtest: verified up to eraseblock 512 > [ 2343.631390] mtd_oobtest: verified up to eraseblock 768 > [ 2343.638788] mtd_oobtest: verified up to eraseblock 1024 > [ 2343.646184] mtd_oobtest: verified up to eraseblock 1280 > [ 2343.653570] mtd_oobtest: verified up to eraseblock 1536 > [ 2343.660970] mtd_oobtest: verified up to eraseblock 1792 > [ 2343.668356] mtd_oobtest: verified 2048 eraseblocks > [ 2343.668369] mtd_oobtest: test 2 of 5 > [ 2350.985635] mtd_oobtest: writing OOBs of whole device > [ 2350.985743] mtd_oobtest: written up to eraseblock 0 > [ 2351.006445] mtd_oobtest: written up to eraseblock 256 > [ 2351.023170] mtd_oobtest: written up to eraseblock 512 > [ 2351.039645] mtd_oobtest: written up to eraseblock 768 > [ 2351.053395] mtd_oobtest: written up to eraseblock 1024 > [ 2351.064954] mtd_oobtest: written up to eraseblock 1280 > [ 2351.074144] mtd_oobtest: written up to eraseblock 1536 > [ 2351.082848] mtd_oobtest: written up to eraseblock 1792 > [ 2351.090707] mtd_oobtest: written 2048 eraseblocks > [ 2351.090721] mtd_oobtest: verifying all eraseblocks > [ 2351.094373] mtd_oobtest: verified up to eraseblock 0 > [ 2351.099353] mtd_oobtest: verified up to eraseblock 256 > [ 2351.104460] mtd_oobtest: verified up to eraseblock 512 > [ 2351.109437] mtd_oobtest: verified up to eraseblock 768 > [ 2351.114528] mtd_oobtest: verified up to eraseblock 1024 > [ 2351.119683] mtd_oobtest: verified up to eraseblock 1280 > [ 2351.124772] mtd_oobtest: verified up to eraseblock 1536 > [ 2351.129996] mtd_oobtest: verified up to eraseblock 1792 > [ 2351.135187] mtd_oobtest: verified 2048 eraseblocks > [ 2351.140130] mtd_oobtest: test 3 of 5 > [ 2358.448438] mtd_oobtest: writing OOBs of whole device > [ 2358.448546] mtd_oobtest: written up to eraseblock 0 > [ 2358.469297] mtd_oobtest: written up to eraseblock 256 > [ 2358.486095] mtd_oobtest: written up to eraseblock 512 > [ 2358.501993] mtd_oobtest: written up to eraseblock 768 > [ 2358.515473] mtd_oobtest: written up to eraseblock 1024 > [ 2358.526708] mtd_oobtest: written up to eraseblock 1280 > [ 2358.535426] mtd_oobtest: written up to eraseblock 1536 > [ 2358.544152] mtd_oobtest: written up to eraseblock 1792 > [ 2358.551732] mtd_oobtest: written 2048 eraseblocks > [ 2358.551744] mtd_oobtest: verifying all eraseblocks > [ 2358.555424] mtd_oobtest: verified up to eraseblock 0 > [ 2358.567572] mtd_oobtest: verified up to eraseblock 256 > [ 2358.575045] mtd_oobtest: verified up to eraseblock 512 > [ 2358.582537] mtd_oobtest: verified up to eraseblock 768 > [ 2358.590024] mtd_oobtest: verified up to eraseblock 1024 > [ 2358.597511] mtd_oobtest: verified up to eraseblock 1280 > [ 2358.604984] mtd_oobtest: verified up to eraseblock 1536 > [ 2358.612468] mtd_oobtest: verified up to eraseblock 1792 > [ 2358.619923] mtd_oobtest: verified 2048 eraseblocks > [ 2358.619936] mtd_oobtest: test 4 of 5 > [ 2365.924669] mtd_oobtest: attempting to start write past end of OOB > [ 2365.924711] mtd_oobtest: an error is expected... > [ 2365.929795] mtd_oobtest: error occurred as expected > [ 2365.934520] mtd_oobtest: attempting to start read past end of OOB > [ 2365.939150] mtd_oobtest: an error is expected... > [ 2365.945371] mtd_oobtest: error occurred as expected > [ 2365.950087] mtd_oobtest: attempting to write past end of device > [ 2365.954660] mtd_oobtest: an error is expected... > [ 2365.960623] mtd_oobtest: error occurred as expected > [ 2365.965422] mtd_oobtest: attempting to read past end of device > [ 2365.970064] mtd_oobtest: an error is expected... > [ 2365.975925] mtd_oobtest: error occurred as expected > [ 2365.984256] mtd_oobtest: attempting to write past end of device > [ 2365.985300] mtd_oobtest: an error is expected... > [ 2365.991242] mtd_oobtest: error: wrote past end of device > [ 2365.996064] mtd_oobtest: attempting to read past end of device > [ 2366.001389] mtd_oobtest: an error is expected... > [ 2366.007028] mtd_oobtest: error: read past end of device > [ 2366.011776] mtd_oobtest: test 5 of 5 > [ 2373.317991] mtd_oobtest: writing OOBs of whole device > [ 2373.318034] mtd_oobtest: written up to eraseblock 0 > [ 2373.322028] mtd_oobtest: written up to eraseblock 0 > [ 2373.327465] mtd_oobtest: written up to eraseblock 256 > [ 2373.331576] mtd_oobtest: written up to eraseblock 256 > [ 2373.337501] mtd_oobtest: written up to eraseblock 512 > [ 2373.341820] mtd_oobtest: written up to eraseblock 512 > [ 2373.347566] mtd_oobtest: written up to eraseblock 768 > [ 2373.351888] mtd_oobtest: written up to eraseblock 768 > [ 2373.357634] mtd_oobtest: written up to eraseblock 1024 > [ 2373.361957] mtd_oobtest: written up to eraseblock 1024 > [ 2373.367710] mtd_oobtest: written up to eraseblock 1280 > [ 2373.372113] mtd_oobtest: written up to eraseblock 1280 > [ 2373.377841] mtd_oobtest: written up to eraseblock 1536 > [ 2373.382355] mtd_oobtest: written up to eraseblock 1536 > [ 2373.387962] mtd_oobtest: written up to eraseblock 1792 > [ 2373.392597] mtd_oobtest: written up to eraseblock 1792 > [ 2373.398190] mtd_oobtest: written 2047 eraseblocks > [ 2373.402838] mtd_oobtest: verifying all eraseblocks > [ 2373.407629] mtd_oobtest: verified up to eraseblock 0 > [ 2373.412483] mtd_oobtest: verified up to eraseblock 256 > [ 2373.417625] mtd_oobtest: verified up to eraseblock 512 > [ 2373.422518] mtd_oobtest: verified up to eraseblock 768 > [ 2373.427650] mtd_oobtest: verified up to eraseblock 1024 > [ 2373.432760] mtd_oobtest: verified up to eraseblock 1280 > [ 2373.437912] mtd_oobtest: verified up to eraseblock 1536 > [ 2373.443091] mtd_oobtest: verified up to eraseblock 1792 > [ 2373.448337] mtd_oobtest: verified 2047 eraseblocks > [ 2373.453358] mtd_oobtest: finished with 2 errors > [ 2373.458250] ================================================= > > Note: the two errors are present even even without this patch when testing > the driver with a flash chip requiring 4 bits ECC strength. > > # insmod mtd_stresstest dev=0 > [ 2383.256453] > [ 2383.256482] ================================================= > [ 2383.257008] mtd_stresstest: MTD device: 0 > [ 2383.262650] mtd_stresstest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 > [ 2383.268254] mtd_test: scanning for bad eraseblocks > [ 2383.281992] mtd_test: scanned 2048 eraseblocks, 0 are bad > [ 2383.285565] mtd_stresstest: doing operations > [ 2383.291047] mtd_stresstest: 0 operations done > [ 2427.841267] mtd_stresstest: 1024 operations done > [ 2471.142229] mtd_stresstest: 2048 operations done > [ 2514.405277] mtd_stresstest: 3072 operations done > [ 2555.451926] mtd_stresstest: 4096 operations done > [ 2598.107133] mtd_stresstest: 5120 operations done > [ 2639.936952] mtd_stresstest: 6144 operations done > [ 2680.724751] mtd_stresstest: 7168 operations done > [ 2720.344163] mtd_stresstest: 8192 operations done > [ 2761.645640] mtd_stresstest: 9216 operations done > [ 2791.760534] mtd_stresstest: finished, 10000 operations done > [ 2791.760817] ================================================= > # Could you please run biterror test "mtd_nandbiterrs" with the same device, since you are adding 8-bit ECC support. Regards, Alam.
2025. 05. 05. 13:17 keltezéssel, Md Sadre Alam írta: > > [...] >> [ 2720.344163] mtd_stresstest: 8192 operations done >> [ 2761.645640] mtd_stresstest: 9216 operations done >> [ 2791.760534] mtd_stresstest: finished, 10000 operations done >> [ 2791.760817] ================================================= >> # > Could you please run biterror test "mtd_nandbiterrs" with the same device, since > you are adding 8-bit ECC support. Sure, here is the result: # insmod mtd_test # for i in $(seq 0 4); do insmod mtd_nandbiterrs; done [ 45.405610] [ 45.405638] ================================================== [ 45.406164] mtd_nandbiterrs: MTD device: 0 [ 45.411807] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 [ 45.415990] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes [ 45.424495] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 [ 45.434686] mtd_nandbiterrs: incremental biterrors test [ 45.436653] mtd_nandbiterrs: write_page [ 45.442634] mtd_nandbiterrs: rewrite page [ 45.446408] mtd_nandbiterrs: read_page [ 45.450346] mtd_nandbiterrs: verify_page [ 45.453320] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage [ 45.457405] mtd_nandbiterrs: Inserted biterror @ 0/5 [ 45.464431] mtd_nandbiterrs: rewrite page [ 45.470216] mtd_nandbiterrs: read_page [ 45.473852] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 45.476909] mtd_nandbiterrs: verify_page [ 45.483090] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage [ 45.487098] mtd_nandbiterrs: Inserted biterror @ 0/2 [ 45.494111] mtd_nandbiterrs: rewrite page [ 45.499850] mtd_nandbiterrs: read_page [ 45.503557] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 45.506597] mtd_nandbiterrs: verify_page [ 45.512777] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage [ 45.516768] mtd_nandbiterrs: Inserted biterror @ 0/0 [ 45.523810] mtd_nandbiterrs: rewrite page [ 45.529586] mtd_nandbiterrs: read_page [ 45.533224] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 45.536305] mtd_nandbiterrs: verify_page [ 45.542464] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage [ 45.546457] mtd_nandbiterrs: Inserted biterror @ 1/7 [ 45.553470] mtd_nandbiterrs: rewrite page [ 45.559244] mtd_nandbiterrs: read_page [ 45.562914] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 45.565991] mtd_nandbiterrs: verify_page [ 45.572153] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage [ 45.576142] mtd_nandbiterrs: Inserted biterror @ 1/5 [ 45.583158] mtd_nandbiterrs: rewrite page [ 45.588927] mtd_nandbiterrs: read_page [ 45.592599] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 45.595680] mtd_nandbiterrs: verify_page [ 45.601840] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage [ 45.605831] mtd_nandbiterrs: Inserted biterror @ 1/2 [ 45.612846] mtd_nandbiterrs: rewrite page [ 45.618618] mtd_nandbiterrs: read_page [ 45.622286] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 45.625434] mtd_nandbiterrs: verify_page [ 45.631528] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage [ 45.635517] mtd_nandbiterrs: Inserted biterror @ 1/0 [ 45.642533] mtd_nandbiterrs: rewrite page [ 45.648303] mtd_nandbiterrs: read_page [ 45.651975] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 45.655055] mtd_nandbiterrs: verify_page [ 45.661215] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage [ 45.665207] mtd_nandbiterrs: Inserted biterror @ 2/6 [ 45.672221] mtd_nandbiterrs: rewrite page [ 45.677987] mtd_nandbiterrs: read_page [ 45.681663] mtd_nandbiterrs: Read reported 3 corrected bit errors [ 45.684741] mtd_nandbiterrs: verify_page [ 45.690902] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage [ 45.694892] mtd_nandbiterrs: Inserted biterror @ 2/5 [ 45.701908] mtd_nandbiterrs: rewrite page [ 45.707678] mtd_nandbiterrs: read_page [ 45.711351] mtd_nandbiterrs: error: read failed at 0x0 [ 45.714431] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 [ 45.722975] mtd_nandbiterrs: finished successfully. [ 45.727101] ================================================== [ 46.200485] [ 46.200512] ================================================== [ 46.201039] mtd_nandbiterrs: MTD device: 0 [ 46.206751] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 [ 46.210763] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes [ 46.219377] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 [ 46.228941] mtd_nandbiterrs: incremental biterrors test [ 46.231522] mtd_nandbiterrs: write_page [ 46.237524] mtd_nandbiterrs: rewrite page [ 46.241199] mtd_nandbiterrs: read_page [ 46.245175] mtd_nandbiterrs: verify_page [ 46.248195] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage [ 46.252254] mtd_nandbiterrs: Inserted biterror @ 0/5 [ 46.259317] mtd_nandbiterrs: rewrite page [ 46.265230] mtd_nandbiterrs: read_page [ 46.268955] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 46.271784] mtd_nandbiterrs: verify_page [ 46.277987] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage [ 46.281941] mtd_nandbiterrs: Inserted biterror @ 0/2 [ 46.288985] mtd_nandbiterrs: rewrite page [ 46.294803] mtd_nandbiterrs: read_page [ 46.298414] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 46.301472] mtd_nandbiterrs: verify_page [ 46.307677] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage [ 46.311629] mtd_nandbiterrs: Inserted biterror @ 0/0 [ 46.318686] mtd_nandbiterrs: rewrite page [ 46.324470] mtd_nandbiterrs: read_page [ 46.328100] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 46.331159] mtd_nandbiterrs: verify_page [ 46.337371] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage [ 46.341316] mtd_nandbiterrs: Inserted biterror @ 1/7 [ 46.348365] mtd_nandbiterrs: rewrite page [ 46.354123] mtd_nandbiterrs: read_page [ 46.357787] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 46.360846] mtd_nandbiterrs: verify_page [ 46.367047] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage [ 46.371003] mtd_nandbiterrs: Inserted biterror @ 1/5 [ 46.378046] mtd_nandbiterrs: rewrite page [ 46.383794] mtd_nandbiterrs: read_page [ 46.387475] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 46.390534] mtd_nandbiterrs: verify_page [ 46.396747] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage [ 46.400691] mtd_nandbiterrs: Inserted biterror @ 1/2 [ 46.407733] mtd_nandbiterrs: rewrite page [ 46.413483] mtd_nandbiterrs: read_page [ 46.417190] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 46.420222] mtd_nandbiterrs: verify_page [ 46.426419] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage [ 46.430379] mtd_nandbiterrs: Inserted biterror @ 1/0 [ 46.437423] mtd_nandbiterrs: rewrite page [ 46.443168] mtd_nandbiterrs: read_page [ 46.446875] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 46.449908] mtd_nandbiterrs: verify_page [ 46.456109] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage [ 46.460066] mtd_nandbiterrs: Inserted biterror @ 2/6 [ 46.467109] mtd_nandbiterrs: rewrite page [ 46.472888] mtd_nandbiterrs: read_page [ 46.476569] mtd_nandbiterrs: Read reported 3 corrected bit errors [ 46.479597] mtd_nandbiterrs: verify_page [ 46.485796] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage [ 46.489753] mtd_nandbiterrs: Inserted biterror @ 2/5 [ 46.496797] mtd_nandbiterrs: rewrite page [ 46.502540] mtd_nandbiterrs: read_page [ 46.506249] mtd_nandbiterrs: error: read failed at 0x0 [ 46.509284] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 [ 46.517867] mtd_nandbiterrs: finished successfully. [ 46.521956] ================================================== [ 47.150313] [ 47.150341] ================================================== [ 47.150867] mtd_nandbiterrs: MTD device: 0 [ 47.156564] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 [ 47.160591] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes [ 47.169201] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 [ 47.178778] mtd_nandbiterrs: incremental biterrors test [ 47.181350] mtd_nandbiterrs: write_page [ 47.187334] mtd_nandbiterrs: rewrite page [ 47.191016] mtd_nandbiterrs: read_page [ 47.194997] mtd_nandbiterrs: verify_page [ 47.198019] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage [ 47.202081] mtd_nandbiterrs: Inserted biterror @ 0/5 [ 47.209132] mtd_nandbiterrs: rewrite page [ 47.214962] mtd_nandbiterrs: read_page [ 47.218554] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 47.221612] mtd_nandbiterrs: verify_page [ 47.227814] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage [ 47.231769] mtd_nandbiterrs: Inserted biterror @ 0/2 [ 47.238816] mtd_nandbiterrs: rewrite page [ 47.244574] mtd_nandbiterrs: read_page [ 47.248242] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 47.251300] mtd_nandbiterrs: verify_page [ 47.257499] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage [ 47.261457] mtd_nandbiterrs: Inserted biterror @ 0/0 [ 47.268504] mtd_nandbiterrs: rewrite page [ 47.274301] mtd_nandbiterrs: read_page [ 47.277930] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 47.280987] mtd_nandbiterrs: verify_page [ 47.287187] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage [ 47.291145] mtd_nandbiterrs: Inserted biterror @ 1/7 [ 47.298191] mtd_nandbiterrs: rewrite page [ 47.303951] mtd_nandbiterrs: read_page [ 47.307619] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 47.310675] mtd_nandbiterrs: verify_page [ 47.316876] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage [ 47.320832] mtd_nandbiterrs: Inserted biterror @ 1/5 [ 47.327875] mtd_nandbiterrs: rewrite page [ 47.333629] mtd_nandbiterrs: read_page [ 47.337305] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 47.340362] mtd_nandbiterrs: verify_page [ 47.346563] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage [ 47.350519] mtd_nandbiterrs: Inserted biterror @ 1/2 [ 47.357561] mtd_nandbiterrs: rewrite page [ 47.363310] mtd_nandbiterrs: read_page [ 47.367021] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 47.370050] mtd_nandbiterrs: verify_page [ 47.376248] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage [ 47.380207] mtd_nandbiterrs: Inserted biterror @ 1/0 [ 47.387250] mtd_nandbiterrs: rewrite page [ 47.392996] mtd_nandbiterrs: read_page [ 47.396703] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 47.399737] mtd_nandbiterrs: verify_page [ 47.405936] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage [ 47.409894] mtd_nandbiterrs: Inserted biterror @ 2/6 [ 47.416938] mtd_nandbiterrs: rewrite page [ 47.422685] mtd_nandbiterrs: read_page [ 47.426387] mtd_nandbiterrs: Read reported 3 corrected bit errors [ 47.429424] mtd_nandbiterrs: verify_page [ 47.435637] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage [ 47.439582] mtd_nandbiterrs: Inserted biterror @ 2/5 [ 47.446624] mtd_nandbiterrs: rewrite page [ 47.452369] mtd_nandbiterrs: read_page [ 47.456080] mtd_nandbiterrs: error: read failed at 0x0 [ 47.459111] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 [ 47.467699] mtd_nandbiterrs: finished successfully. [ 47.471784] ================================================== [ 48.080311] [ 48.080339] ================================================== [ 48.080866] mtd_nandbiterrs: MTD device: 0 [ 48.086560] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 [ 48.090590] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes [ 48.099204] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 [ 48.108765] mtd_nandbiterrs: incremental biterrors test [ 48.111353] mtd_nandbiterrs: write_page [ 48.117325] mtd_nandbiterrs: rewrite page [ 48.121017] mtd_nandbiterrs: read_page [ 48.124996] mtd_nandbiterrs: verify_page [ 48.128017] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage [ 48.132080] mtd_nandbiterrs: Inserted biterror @ 0/5 [ 48.139131] mtd_nandbiterrs: rewrite page [ 48.144881] mtd_nandbiterrs: read_page [ 48.148552] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 48.151611] mtd_nandbiterrs: verify_page [ 48.157816] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage [ 48.161768] mtd_nandbiterrs: Inserted biterror @ 0/2 [ 48.168891] mtd_nandbiterrs: rewrite page [ 48.174571] mtd_nandbiterrs: read_page [ 48.178241] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 48.181299] mtd_nandbiterrs: verify_page [ 48.187500] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage [ 48.191455] mtd_nandbiterrs: Inserted biterror @ 0/0 [ 48.198506] mtd_nandbiterrs: rewrite page [ 48.204299] mtd_nandbiterrs: read_page [ 48.207931] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 48.210985] mtd_nandbiterrs: verify_page [ 48.217187] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage [ 48.221142] mtd_nandbiterrs: Inserted biterror @ 1/7 [ 48.228188] mtd_nandbiterrs: rewrite page [ 48.233950] mtd_nandbiterrs: read_page [ 48.237617] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 48.240673] mtd_nandbiterrs: verify_page [ 48.246872] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage [ 48.250831] mtd_nandbiterrs: Inserted biterror @ 1/5 [ 48.257875] mtd_nandbiterrs: rewrite page [ 48.263631] mtd_nandbiterrs: read_page [ 48.267303] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 48.270361] mtd_nandbiterrs: verify_page [ 48.276560] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage [ 48.280531] mtd_nandbiterrs: Inserted biterror @ 1/2 [ 48.287592] mtd_nandbiterrs: rewrite page [ 48.293338] mtd_nandbiterrs: read_page [ 48.297030] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 48.300049] mtd_nandbiterrs: verify_page [ 48.306247] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage [ 48.310205] mtd_nandbiterrs: Inserted biterror @ 1/0 [ 48.317250] mtd_nandbiterrs: rewrite page [ 48.322994] mtd_nandbiterrs: read_page [ 48.326705] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 48.329736] mtd_nandbiterrs: verify_page [ 48.335935] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage [ 48.339892] mtd_nandbiterrs: Inserted biterror @ 2/6 [ 48.346936] mtd_nandbiterrs: rewrite page [ 48.352633] mtd_nandbiterrs: read_page [ 48.356391] mtd_nandbiterrs: Read reported 3 corrected bit errors [ 48.359423] mtd_nandbiterrs: verify_page [ 48.365626] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage [ 48.369581] mtd_nandbiterrs: Inserted biterror @ 2/5 [ 48.376627] mtd_nandbiterrs: rewrite page [ 48.382322] mtd_nandbiterrs: read_page [ 48.386077] mtd_nandbiterrs: error: read failed at 0x0 [ 48.389110] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 [ 48.397695] mtd_nandbiterrs: finished successfully. [ 48.401783] ================================================== [ 48.940558] [ 48.940586] ================================================== [ 48.941112] mtd_nandbiterrs: MTD device: 0 [ 48.946811] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 [ 48.950837] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes [ 48.959448] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 [ 48.969014] mtd_nandbiterrs: incremental biterrors test [ 48.971596] mtd_nandbiterrs: write_page [ 48.977594] mtd_nandbiterrs: rewrite page [ 48.981277] mtd_nandbiterrs: read_page [ 48.985247] mtd_nandbiterrs: verify_page [ 48.988269] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage [ 48.992327] mtd_nandbiterrs: Inserted biterror @ 0/5 [ 48.999428] mtd_nandbiterrs: rewrite page [ 49.005508] mtd_nandbiterrs: read_page [ 49.008836] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 49.011858] mtd_nandbiterrs: verify_page [ 49.018061] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage [ 49.022015] mtd_nandbiterrs: Inserted biterror @ 0/2 [ 49.029058] mtd_nandbiterrs: rewrite page [ 49.034848] mtd_nandbiterrs: read_page [ 49.038516] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 49.041545] mtd_nandbiterrs: verify_page [ 49.047755] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage [ 49.051702] mtd_nandbiterrs: Inserted biterror @ 0/0 [ 49.058760] mtd_nandbiterrs: rewrite page [ 49.064565] mtd_nandbiterrs: read_page [ 49.068203] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 49.071232] mtd_nandbiterrs: verify_page [ 49.077432] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage [ 49.081389] mtd_nandbiterrs: Inserted biterror @ 1/7 [ 49.088432] mtd_nandbiterrs: rewrite page [ 49.094197] mtd_nandbiterrs: read_page [ 49.097889] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 49.100919] mtd_nandbiterrs: verify_page [ 49.107121] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage [ 49.111077] mtd_nandbiterrs: Inserted biterror @ 1/5 [ 49.118137] mtd_nandbiterrs: rewrite page [ 49.123892] mtd_nandbiterrs: read_page [ 49.127576] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 49.130608] mtd_nandbiterrs: verify_page [ 49.136808] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage [ 49.140764] mtd_nandbiterrs: Inserted biterror @ 1/2 [ 49.147807] mtd_nandbiterrs: rewrite page [ 49.153607] mtd_nandbiterrs: read_page [ 49.157268] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 49.160294] mtd_nandbiterrs: verify_page [ 49.166496] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage [ 49.170452] mtd_nandbiterrs: Inserted biterror @ 1/0 [ 49.177498] mtd_nandbiterrs: rewrite page [ 49.183253] mtd_nandbiterrs: read_page [ 49.186974] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 49.189983] mtd_nandbiterrs: verify_page [ 49.196194] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage [ 49.200140] mtd_nandbiterrs: Inserted biterror @ 2/6 [ 49.207182] mtd_nandbiterrs: rewrite page [ 49.212895] mtd_nandbiterrs: read_page [ 49.216671] mtd_nandbiterrs: Read reported 3 corrected bit errors [ 49.219670] mtd_nandbiterrs: verify_page [ 49.225872] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage [ 49.229827] mtd_nandbiterrs: Inserted biterror @ 2/5 [ 49.236871] mtd_nandbiterrs: rewrite page [ 49.242629] mtd_nandbiterrs: read_page [ 49.246348] mtd_nandbiterrs: error: read failed at 0x0 [ 49.249356] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 [ 49.257958] mtd_nandbiterrs: finished successfully. [ 49.262029] ================================================== # Regards, Gabor
On 05/05/2025 at 15:21:52 +02, Gabor Juhos <j4g8y7@gmail.com> wrote: > 2025. 05. 05. 13:17 keltezéssel, Md Sadre Alam írta: >> >> > > [...] > >>> [ 2720.344163] mtd_stresstest: 8192 operations done >>> [ 2761.645640] mtd_stresstest: 9216 operations done >>> [ 2791.760534] mtd_stresstest: finished, 10000 operations done >>> [ 2791.760817] ================================================= >>> # >> Could you please run biterror test "mtd_nandbiterrs" with the same device, since >> you are adding 8-bit ECC support. > > Sure, here is the result: > > # insmod mtd_test > # for i in $(seq 0 4); do insmod mtd_nandbiterrs; done > [ 45.405610] > [ 45.405638] ================================================== > [ 45.406164] mtd_nandbiterrs: MTD device: 0 > [ 45.411807] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, > page=2048, oob=128 > [ 45.415990] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes > [ 45.424495] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 > [ 45.434686] mtd_nandbiterrs: incremental biterrors test > [ 45.436653] mtd_nandbiterrs: write_page > [ 45.442634] mtd_nandbiterrs: rewrite page > [ 45.446408] mtd_nandbiterrs: read_page > [ 45.450346] mtd_nandbiterrs: verify_page > [ 45.453320] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage > [ 45.457405] mtd_nandbiterrs: Inserted biterror @ 0/5 > [ 45.464431] mtd_nandbiterrs: rewrite page > [ 45.470216] mtd_nandbiterrs: read_page > [ 45.473852] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 45.476909] mtd_nandbiterrs: verify_page > [ 45.483090] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage > [ 45.487098] mtd_nandbiterrs: Inserted biterror @ 0/2 > [ 45.494111] mtd_nandbiterrs: rewrite page > [ 45.499850] mtd_nandbiterrs: read_page > [ 45.503557] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 45.506597] mtd_nandbiterrs: verify_page > [ 45.512777] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage > [ 45.516768] mtd_nandbiterrs: Inserted biterror @ 0/0 > [ 45.523810] mtd_nandbiterrs: rewrite page > [ 45.529586] mtd_nandbiterrs: read_page > [ 45.533224] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 45.536305] mtd_nandbiterrs: verify_page > [ 45.542464] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage > [ 45.546457] mtd_nandbiterrs: Inserted biterror @ 1/7 > [ 45.553470] mtd_nandbiterrs: rewrite page > [ 45.559244] mtd_nandbiterrs: read_page > [ 45.562914] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 45.565991] mtd_nandbiterrs: verify_page > [ 45.572153] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage > [ 45.576142] mtd_nandbiterrs: Inserted biterror @ 1/5 > [ 45.583158] mtd_nandbiterrs: rewrite page > [ 45.588927] mtd_nandbiterrs: read_page > [ 45.592599] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 45.595680] mtd_nandbiterrs: verify_page > [ 45.601840] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage > [ 45.605831] mtd_nandbiterrs: Inserted biterror @ 1/2 > [ 45.612846] mtd_nandbiterrs: rewrite page > [ 45.618618] mtd_nandbiterrs: read_page > [ 45.622286] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 45.625434] mtd_nandbiterrs: verify_page > [ 45.631528] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage > [ 45.635517] mtd_nandbiterrs: Inserted biterror @ 1/0 > [ 45.642533] mtd_nandbiterrs: rewrite page > [ 45.648303] mtd_nandbiterrs: read_page > [ 45.651975] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 45.655055] mtd_nandbiterrs: verify_page > [ 45.661215] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage > [ 45.665207] mtd_nandbiterrs: Inserted biterror @ 2/6 > [ 45.672221] mtd_nandbiterrs: rewrite page > [ 45.677987] mtd_nandbiterrs: read_page > [ 45.681663] mtd_nandbiterrs: Read reported 3 corrected bit errors > [ 45.684741] mtd_nandbiterrs: verify_page > [ 45.690902] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage > [ 45.694892] mtd_nandbiterrs: Inserted biterror @ 2/5 > [ 45.701908] mtd_nandbiterrs: rewrite page > [ 45.707678] mtd_nandbiterrs: read_page > [ 45.711351] mtd_nandbiterrs: error: read failed at 0x0 > [ 45.714431] mtd_nandbiterrs: After 9 biterrors per subpage, read reported > error -74 > [ 45.722975] mtd_nandbiterrs: finished successfully. > [ 45.727101] ================================================== > [ 46.200485] > [ 46.200512] ================================================== > [ 46.201039] mtd_nandbiterrs: MTD device: 0 > [ 46.206751] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, > page=2048, oob=128 > [ 46.210763] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes > [ 46.219377] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 > [ 46.228941] mtd_nandbiterrs: incremental biterrors test > [ 46.231522] mtd_nandbiterrs: write_page > [ 46.237524] mtd_nandbiterrs: rewrite page > [ 46.241199] mtd_nandbiterrs: read_page > [ 46.245175] mtd_nandbiterrs: verify_page > [ 46.248195] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage > [ 46.252254] mtd_nandbiterrs: Inserted biterror @ 0/5 > [ 46.259317] mtd_nandbiterrs: rewrite page > [ 46.265230] mtd_nandbiterrs: read_page > [ 46.268955] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 46.271784] mtd_nandbiterrs: verify_page > [ 46.277987] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage > [ 46.281941] mtd_nandbiterrs: Inserted biterror @ 0/2 > [ 46.288985] mtd_nandbiterrs: rewrite page > [ 46.294803] mtd_nandbiterrs: read_page > [ 46.298414] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 46.301472] mtd_nandbiterrs: verify_page > [ 46.307677] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage > [ 46.311629] mtd_nandbiterrs: Inserted biterror @ 0/0 > [ 46.318686] mtd_nandbiterrs: rewrite page > [ 46.324470] mtd_nandbiterrs: read_page > [ 46.328100] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 46.331159] mtd_nandbiterrs: verify_page > [ 46.337371] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage > [ 46.341316] mtd_nandbiterrs: Inserted biterror @ 1/7 > [ 46.348365] mtd_nandbiterrs: rewrite page > [ 46.354123] mtd_nandbiterrs: read_page > [ 46.357787] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 46.360846] mtd_nandbiterrs: verify_page > [ 46.367047] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage > [ 46.371003] mtd_nandbiterrs: Inserted biterror @ 1/5 > [ 46.378046] mtd_nandbiterrs: rewrite page > [ 46.383794] mtd_nandbiterrs: read_page > [ 46.387475] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 46.390534] mtd_nandbiterrs: verify_page > [ 46.396747] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage > [ 46.400691] mtd_nandbiterrs: Inserted biterror @ 1/2 > [ 46.407733] mtd_nandbiterrs: rewrite page > [ 46.413483] mtd_nandbiterrs: read_page > [ 46.417190] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 46.420222] mtd_nandbiterrs: verify_page > [ 46.426419] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage > [ 46.430379] mtd_nandbiterrs: Inserted biterror @ 1/0 > [ 46.437423] mtd_nandbiterrs: rewrite page > [ 46.443168] mtd_nandbiterrs: read_page > [ 46.446875] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 46.449908] mtd_nandbiterrs: verify_page > [ 46.456109] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage > [ 46.460066] mtd_nandbiterrs: Inserted biterror @ 2/6 > [ 46.467109] mtd_nandbiterrs: rewrite page > [ 46.472888] mtd_nandbiterrs: read_page > [ 46.476569] mtd_nandbiterrs: Read reported 3 corrected bit errors > [ 46.479597] mtd_nandbiterrs: verify_page > [ 46.485796] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage > [ 46.489753] mtd_nandbiterrs: Inserted biterror @ 2/5 > [ 46.496797] mtd_nandbiterrs: rewrite page > [ 46.502540] mtd_nandbiterrs: read_page > [ 46.506249] mtd_nandbiterrs: error: read failed at 0x0 > [ 46.509284] mtd_nandbiterrs: After 9 biterrors per subpage, read reported > error -74 > [ 46.517867] mtd_nandbiterrs: finished successfully. > [ 46.521956] ================================================== > [ 47.150313] > [ 47.150341] ================================================== > [ 47.150867] mtd_nandbiterrs: MTD device: 0 > [ 47.156564] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, > page=2048, oob=128 > [ 47.160591] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes > [ 47.169201] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 > [ 47.178778] mtd_nandbiterrs: incremental biterrors test > [ 47.181350] mtd_nandbiterrs: write_page > [ 47.187334] mtd_nandbiterrs: rewrite page > [ 47.191016] mtd_nandbiterrs: read_page > [ 47.194997] mtd_nandbiterrs: verify_page > [ 47.198019] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage > [ 47.202081] mtd_nandbiterrs: Inserted biterror @ 0/5 > [ 47.209132] mtd_nandbiterrs: rewrite page > [ 47.214962] mtd_nandbiterrs: read_page > [ 47.218554] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 47.221612] mtd_nandbiterrs: verify_page > [ 47.227814] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage > [ 47.231769] mtd_nandbiterrs: Inserted biterror @ 0/2 > [ 47.238816] mtd_nandbiterrs: rewrite page > [ 47.244574] mtd_nandbiterrs: read_page > [ 47.248242] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 47.251300] mtd_nandbiterrs: verify_page > [ 47.257499] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage > [ 47.261457] mtd_nandbiterrs: Inserted biterror @ 0/0 > [ 47.268504] mtd_nandbiterrs: rewrite page > [ 47.274301] mtd_nandbiterrs: read_page > [ 47.277930] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 47.280987] mtd_nandbiterrs: verify_page > [ 47.287187] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage > [ 47.291145] mtd_nandbiterrs: Inserted biterror @ 1/7 > [ 47.298191] mtd_nandbiterrs: rewrite page > [ 47.303951] mtd_nandbiterrs: read_page > [ 47.307619] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 47.310675] mtd_nandbiterrs: verify_page > [ 47.316876] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage > [ 47.320832] mtd_nandbiterrs: Inserted biterror @ 1/5 > [ 47.327875] mtd_nandbiterrs: rewrite page > [ 47.333629] mtd_nandbiterrs: read_page > [ 47.337305] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 47.340362] mtd_nandbiterrs: verify_page > [ 47.346563] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage > [ 47.350519] mtd_nandbiterrs: Inserted biterror @ 1/2 > [ 47.357561] mtd_nandbiterrs: rewrite page > [ 47.363310] mtd_nandbiterrs: read_page > [ 47.367021] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 47.370050] mtd_nandbiterrs: verify_page > [ 47.376248] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage > [ 47.380207] mtd_nandbiterrs: Inserted biterror @ 1/0 > [ 47.387250] mtd_nandbiterrs: rewrite page > [ 47.392996] mtd_nandbiterrs: read_page > [ 47.396703] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 47.399737] mtd_nandbiterrs: verify_page > [ 47.405936] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage > [ 47.409894] mtd_nandbiterrs: Inserted biterror @ 2/6 > [ 47.416938] mtd_nandbiterrs: rewrite page > [ 47.422685] mtd_nandbiterrs: read_page > [ 47.426387] mtd_nandbiterrs: Read reported 3 corrected bit errors > [ 47.429424] mtd_nandbiterrs: verify_page > [ 47.435637] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage > [ 47.439582] mtd_nandbiterrs: Inserted biterror @ 2/5 > [ 47.446624] mtd_nandbiterrs: rewrite page > [ 47.452369] mtd_nandbiterrs: read_page > [ 47.456080] mtd_nandbiterrs: error: read failed at 0x0 > [ 47.459111] mtd_nandbiterrs: After 9 biterrors per subpage, read reported > error -74 > [ 47.467699] mtd_nandbiterrs: finished successfully. > [ 47.471784] ================================================== > [ 48.080311] > [ 48.080339] ================================================== > [ 48.080866] mtd_nandbiterrs: MTD device: 0 > [ 48.086560] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, > page=2048, oob=128 > [ 48.090590] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes > [ 48.099204] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 > [ 48.108765] mtd_nandbiterrs: incremental biterrors test > [ 48.111353] mtd_nandbiterrs: write_page > [ 48.117325] mtd_nandbiterrs: rewrite page > [ 48.121017] mtd_nandbiterrs: read_page > [ 48.124996] mtd_nandbiterrs: verify_page > [ 48.128017] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage > [ 48.132080] mtd_nandbiterrs: Inserted biterror @ 0/5 > [ 48.139131] mtd_nandbiterrs: rewrite page > [ 48.144881] mtd_nandbiterrs: read_page > [ 48.148552] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 48.151611] mtd_nandbiterrs: verify_page > [ 48.157816] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage > [ 48.161768] mtd_nandbiterrs: Inserted biterror @ 0/2 > [ 48.168891] mtd_nandbiterrs: rewrite page > [ 48.174571] mtd_nandbiterrs: read_page > [ 48.178241] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 48.181299] mtd_nandbiterrs: verify_page > [ 48.187500] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage > [ 48.191455] mtd_nandbiterrs: Inserted biterror @ 0/0 > [ 48.198506] mtd_nandbiterrs: rewrite page > [ 48.204299] mtd_nandbiterrs: read_page > [ 48.207931] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 48.210985] mtd_nandbiterrs: verify_page > [ 48.217187] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage > [ 48.221142] mtd_nandbiterrs: Inserted biterror @ 1/7 > [ 48.228188] mtd_nandbiterrs: rewrite page > [ 48.233950] mtd_nandbiterrs: read_page > [ 48.237617] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 48.240673] mtd_nandbiterrs: verify_page > [ 48.246872] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage > [ 48.250831] mtd_nandbiterrs: Inserted biterror @ 1/5 > [ 48.257875] mtd_nandbiterrs: rewrite page > [ 48.263631] mtd_nandbiterrs: read_page > [ 48.267303] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 48.270361] mtd_nandbiterrs: verify_page > [ 48.276560] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage > [ 48.280531] mtd_nandbiterrs: Inserted biterror @ 1/2 > [ 48.287592] mtd_nandbiterrs: rewrite page > [ 48.293338] mtd_nandbiterrs: read_page > [ 48.297030] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 48.300049] mtd_nandbiterrs: verify_page > [ 48.306247] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage > [ 48.310205] mtd_nandbiterrs: Inserted biterror @ 1/0 > [ 48.317250] mtd_nandbiterrs: rewrite page > [ 48.322994] mtd_nandbiterrs: read_page > [ 48.326705] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 48.329736] mtd_nandbiterrs: verify_page > [ 48.335935] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage > [ 48.339892] mtd_nandbiterrs: Inserted biterror @ 2/6 > [ 48.346936] mtd_nandbiterrs: rewrite page > [ 48.352633] mtd_nandbiterrs: read_page > [ 48.356391] mtd_nandbiterrs: Read reported 3 corrected bit errors > [ 48.359423] mtd_nandbiterrs: verify_page > [ 48.365626] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage > [ 48.369581] mtd_nandbiterrs: Inserted biterror @ 2/5 > [ 48.376627] mtd_nandbiterrs: rewrite page > [ 48.382322] mtd_nandbiterrs: read_page > [ 48.386077] mtd_nandbiterrs: error: read failed at 0x0 > [ 48.389110] mtd_nandbiterrs: After 9 biterrors per subpage, read reported > error -74 > [ 48.397695] mtd_nandbiterrs: finished successfully. > [ 48.401783] ================================================== > [ 48.940558] > [ 48.940586] ================================================== > [ 48.941112] mtd_nandbiterrs: MTD device: 0 > [ 48.946811] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, > page=2048, oob=128 > [ 48.950837] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes > [ 48.959448] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 > [ 48.969014] mtd_nandbiterrs: incremental biterrors test > [ 48.971596] mtd_nandbiterrs: write_page > [ 48.977594] mtd_nandbiterrs: rewrite page > [ 48.981277] mtd_nandbiterrs: read_page > [ 48.985247] mtd_nandbiterrs: verify_page > [ 48.988269] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage > [ 48.992327] mtd_nandbiterrs: Inserted biterror @ 0/5 > [ 48.999428] mtd_nandbiterrs: rewrite page > [ 49.005508] mtd_nandbiterrs: read_page > [ 49.008836] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 49.011858] mtd_nandbiterrs: verify_page > [ 49.018061] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage > [ 49.022015] mtd_nandbiterrs: Inserted biterror @ 0/2 > [ 49.029058] mtd_nandbiterrs: rewrite page > [ 49.034848] mtd_nandbiterrs: read_page > [ 49.038516] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 49.041545] mtd_nandbiterrs: verify_page > [ 49.047755] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage > [ 49.051702] mtd_nandbiterrs: Inserted biterror @ 0/0 > [ 49.058760] mtd_nandbiterrs: rewrite page > [ 49.064565] mtd_nandbiterrs: read_page > [ 49.068203] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 49.071232] mtd_nandbiterrs: verify_page > [ 49.077432] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage > [ 49.081389] mtd_nandbiterrs: Inserted biterror @ 1/7 > [ 49.088432] mtd_nandbiterrs: rewrite page > [ 49.094197] mtd_nandbiterrs: read_page > [ 49.097889] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 49.100919] mtd_nandbiterrs: verify_page > [ 49.107121] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage > [ 49.111077] mtd_nandbiterrs: Inserted biterror @ 1/5 > [ 49.118137] mtd_nandbiterrs: rewrite page > [ 49.123892] mtd_nandbiterrs: read_page > [ 49.127576] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 49.130608] mtd_nandbiterrs: verify_page > [ 49.136808] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage > [ 49.140764] mtd_nandbiterrs: Inserted biterror @ 1/2 > [ 49.147807] mtd_nandbiterrs: rewrite page > [ 49.153607] mtd_nandbiterrs: read_page > [ 49.157268] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 49.160294] mtd_nandbiterrs: verify_page > [ 49.166496] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage > [ 49.170452] mtd_nandbiterrs: Inserted biterror @ 1/0 > [ 49.177498] mtd_nandbiterrs: rewrite page > [ 49.183253] mtd_nandbiterrs: read_page > [ 49.186974] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 49.189983] mtd_nandbiterrs: verify_page > [ 49.196194] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage > [ 49.200140] mtd_nandbiterrs: Inserted biterror @ 2/6 > [ 49.207182] mtd_nandbiterrs: rewrite page > [ 49.212895] mtd_nandbiterrs: read_page > [ 49.216671] mtd_nandbiterrs: Read reported 3 corrected bit errors > [ 49.219670] mtd_nandbiterrs: verify_page > [ 49.225872] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage > [ 49.229827] mtd_nandbiterrs: Inserted biterror @ 2/5 > [ 49.236871] mtd_nandbiterrs: rewrite page > [ 49.242629] mtd_nandbiterrs: read_page > [ 49.246348] mtd_nandbiterrs: error: read failed at 0x0 > [ 49.249356] mtd_nandbiterrs: After 9 biterrors per subpage, read reported > error -74 > [ 49.257958] mtd_nandbiterrs: finished successfully. > [ 49.262029] ================================================== > # This is not the intended behavior. The reporting is wrong and should report an increasing number of bitflips instead of 1, 1, 1, 2, 2, 2, 2, 3. With this behavior, wear levelling will not work correctly. This is not related to Gabor's changes, but I believe this should be updated otherwise it does not make much sense to increase the strength. Gabor, can you look into it? Both patches look fine otherwise, thanks a lot! Miquèl
2025. 05. 12. 10:32 keltezéssel, Miquel Raynal írta: > On 05/05/2025 at 15:21:52 +02, Gabor Juhos <j4g8y7@gmail.com> wrote: > >> 2025. 05. 05. 13:17 keltezéssel, Md Sadre Alam írta: >>> >>> >> [...] >> [ 48.940586] ================================================== >> [ 48.941112] mtd_nandbiterrs: MTD device: 0 >> [ 48.946811] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, >> page=2048, oob=128 >> [ 48.950837] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes >> [ 48.959448] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 >> [ 48.969014] mtd_nandbiterrs: incremental biterrors test >> [ 48.971596] mtd_nandbiterrs: write_page >> [ 48.977594] mtd_nandbiterrs: rewrite page >> [ 48.981277] mtd_nandbiterrs: read_page >> [ 48.985247] mtd_nandbiterrs: verify_page >> [ 48.988269] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage >> [ 48.992327] mtd_nandbiterrs: Inserted biterror @ 0/5 >> [ 48.999428] mtd_nandbiterrs: rewrite page >> [ 49.005508] mtd_nandbiterrs: read_page >> [ 49.008836] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 49.011858] mtd_nandbiterrs: verify_page >> [ 49.018061] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage >> [ 49.022015] mtd_nandbiterrs: Inserted biterror @ 0/2 >> [ 49.029058] mtd_nandbiterrs: rewrite page >> [ 49.034848] mtd_nandbiterrs: read_page >> [ 49.038516] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 49.041545] mtd_nandbiterrs: verify_page >> [ 49.047755] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage >> [ 49.051702] mtd_nandbiterrs: Inserted biterror @ 0/0 >> [ 49.058760] mtd_nandbiterrs: rewrite page >> [ 49.064565] mtd_nandbiterrs: read_page >> [ 49.068203] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 49.071232] mtd_nandbiterrs: verify_page >> [ 49.077432] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage >> [ 49.081389] mtd_nandbiterrs: Inserted biterror @ 1/7 >> [ 49.088432] mtd_nandbiterrs: rewrite page >> [ 49.094197] mtd_nandbiterrs: read_page >> [ 49.097889] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 49.100919] mtd_nandbiterrs: verify_page >> [ 49.107121] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage >> [ 49.111077] mtd_nandbiterrs: Inserted biterror @ 1/5 >> [ 49.118137] mtd_nandbiterrs: rewrite page >> [ 49.123892] mtd_nandbiterrs: read_page >> [ 49.127576] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 49.130608] mtd_nandbiterrs: verify_page >> [ 49.136808] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage >> [ 49.140764] mtd_nandbiterrs: Inserted biterror @ 1/2 >> [ 49.147807] mtd_nandbiterrs: rewrite page >> [ 49.153607] mtd_nandbiterrs: read_page >> [ 49.157268] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 49.160294] mtd_nandbiterrs: verify_page >> [ 49.166496] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage >> [ 49.170452] mtd_nandbiterrs: Inserted biterror @ 1/0 >> [ 49.177498] mtd_nandbiterrs: rewrite page >> [ 49.183253] mtd_nandbiterrs: read_page >> [ 49.186974] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 49.189983] mtd_nandbiterrs: verify_page >> [ 49.196194] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage >> [ 49.200140] mtd_nandbiterrs: Inserted biterror @ 2/6 >> [ 49.207182] mtd_nandbiterrs: rewrite page >> [ 49.212895] mtd_nandbiterrs: read_page >> [ 49.216671] mtd_nandbiterrs: Read reported 3 corrected bit errors >> [ 49.219670] mtd_nandbiterrs: verify_page >> [ 49.225872] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage >> [ 49.229827] mtd_nandbiterrs: Inserted biterror @ 2/5 >> [ 49.236871] mtd_nandbiterrs: rewrite page >> [ 49.242629] mtd_nandbiterrs: read_page >> [ 49.246348] mtd_nandbiterrs: error: read failed at 0x0 >> [ 49.249356] mtd_nandbiterrs: After 9 biterrors per subpage, read reported >> error -74 >> [ 49.257958] mtd_nandbiterrs: finished successfully. >> [ 49.262029] ================================================== >> # > > This is not the intended behavior. The reporting is wrong and should > report an increasing number of bitflips instead of 1, 1, 1, 2, 2, 2, 2, > 3. > > With this behavior, wear levelling will not work correctly. > > This is not related to Gabor's changes, but I believe this should be > updated otherwise it does not make much sense to increase the strength. It still makes some sense. For example, the bootloader on my board uses 8 bits strength when it handles the NAND flash. Without supporting that, the kernel can't read the data written by the bootloader and vice versa. > Gabor, can you look into it? Both patches look fine otherwise, thanks a > lot! I have checked it. According to the code, the driver reads the reported values from a hardware register. Here is the result of another test but i have added some debug code to the driver so the output contains the hardware register values: # insmod mtd_nandbiterrs dev=0 [ 64.791395] [ 64.791423] ================================================== [ 64.791950] mtd_nandbiterrs: MTD device: 0 [ 64.797592] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 [ 64.801779] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes [ 64.810313] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 [ 64.820832] mtd_nandbiterrs: incremental biterrors test [ 64.822452] mtd_nandbiterrs: write_page [ 64.828511] mtd_nandbiterrs: rewrite page [ 64.832270] mtd_nandbiterrs: read_page [ 64.836184] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0200 erased_cw:00000002 [ 64.839091] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 64.847364] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 64.855694] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 64.864020] qcom_snand 79b0000.spi: corrected:0 failed:0 bitflips:0 [ 64.872349] mtd_nandbiterrs: verify_page [ 64.878598] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage [ 64.882760] mtd_nandbiterrs: Inserted biterror @ 0/5 [ 64.889793] mtd_nandbiterrs: rewrite page [ 64.895541] mtd_nandbiterrs: read_page [ 64.899228] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 [ 64.902282] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 64.910549] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 64.918860] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 64.927206] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 [ 64.935552] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 64.941789] mtd_nandbiterrs: verify_page [ 64.948043] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage [ 64.952042] mtd_nandbiterrs: Inserted biterror @ 0/2 [ 64.959048] mtd_nandbiterrs: rewrite page [ 64.964815] mtd_nandbiterrs: read_page [ 64.968490] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 [ 64.971586] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 64.979814] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 64.988131] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 64.996481] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 [ 65.004810] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 65.011059] mtd_nandbiterrs: verify_page [ 65.017313] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage [ 65.021307] mtd_nandbiterrs: Inserted biterror @ 0/0 [ 65.028319] mtd_nandbiterrs: rewrite page [ 65.034131] mtd_nandbiterrs: read_page [ 65.037862] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 [ 65.040844] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 65.049069] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 65.057418] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 65.065763] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 [ 65.074082] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 65.080341] mtd_nandbiterrs: verify_page [ 65.086584] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage [ 65.090574] mtd_nandbiterrs: Inserted biterror @ 1/7 [ 65.097589] mtd_nandbiterrs: rewrite page [ 65.103374] mtd_nandbiterrs: read_page [ 65.107030] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 [ 65.110120] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 65.118340] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 65.126689] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 65.135032] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 [ 65.143357] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 65.149611] mtd_nandbiterrs: verify_page [ 65.155855] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage [ 65.159844] mtd_nandbiterrs: Inserted biterror @ 1/5 [ 65.166860] mtd_nandbiterrs: rewrite page [ 65.172645] mtd_nandbiterrs: read_page [ 65.176301] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 [ 65.179389] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 65.187611] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 65.195961] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 65.204289] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 [ 65.212623] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 65.218858] mtd_nandbiterrs: verify_page [ 65.225139] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage [ 65.229102] mtd_nandbiterrs: Inserted biterror @ 1/2 [ 65.236147] mtd_nandbiterrs: rewrite page [ 65.241899] mtd_nandbiterrs: read_page [ 65.245572] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 [ 65.248635] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 65.256902] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 65.265234] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 65.273561] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 [ 65.281895] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 65.288129] mtd_nandbiterrs: verify_page [ 65.294408] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage [ 65.298373] mtd_nandbiterrs: Inserted biterror @ 1/0 [ 65.305413] mtd_nandbiterrs: rewrite page [ 65.311170] mtd_nandbiterrs: read_page [ 65.314843] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 [ 65.317906] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 65.326170] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 65.334501] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 65.342833] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 [ 65.351164] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 65.357399] mtd_nandbiterrs: verify_page [ 65.363680] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage [ 65.367643] mtd_nandbiterrs: Inserted biterror @ 2/6 [ 65.374684] mtd_nandbiterrs: rewrite page [ 65.380445] mtd_nandbiterrs: read_page [ 65.384112] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0203 erased_cw:00000002 [ 65.387177] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 65.395445] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 65.403769] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 65.412103] qcom_snand 79b0000.spi: corrected:3 failed:0 bitflips:3 [ 65.420436] mtd_nandbiterrs: Read reported 3 corrected bit errors [ 65.426671] mtd_nandbiterrs: verify_page [ 65.432950] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage [ 65.436915] mtd_nandbiterrs: Inserted biterror @ 2/5 [ 65.443958] mtd_nandbiterrs: rewrite page [ 65.449719] mtd_nandbiterrs: read_page [ 65.453386] qcom_snand 79b0000.spi: cw[0] flash:00003030 buffer:00ff0301 erased_cw:00000002 [ 65.456448] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 65.464715] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 65.473041] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 65.481374] qcom_snand 79b0000.spi: corrected:0 failed:1 bitflips:3 [ 65.489706] mtd_nandbiterrs: error: read failed at 0x0 [ 65.495941] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 [ 65.504609] mtd_nandbiterrs: finished successfully. [ 65.508700] ================================================== Basically, the driver reads the page as 4 codewords along with reading the register values after each. The reported values are coming from the low 5 bits of the 'buffer' values printed above. The layout of the register is barely documented in the driver, so the exact meaning of the bits is unknown. Despite that, I had an idea, so I have changed the code in the nandbiterrs module to insert only single bit error into a given byte. By doing the test with the modified module results in the following: # insmod mtd_nandbiterrs dev=0 [ 37.125416] [ 37.125444] ================================================== [ 37.125970] mtd_nandbiterrs: MTD device: 0 [ 37.131764] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 [ 37.135695] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes [ 37.144314] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 [ 37.155047] mtd_nandbiterrs: incremental biterrors test [ 37.156481] mtd_nandbiterrs: write_page [ 37.162518] mtd_nandbiterrs: rewrite page [ 37.166298] mtd_nandbiterrs: read_page [ 37.170193] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0200 erased_cw:00000002 [ 37.173111] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.181383] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.189708] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.198020] qcom_snand 79b0000.spi: corrected:0 failed:0 bitflips:0 [ 37.206367] mtd_nandbiterrs: verify_page [ 37.212631] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage [ 37.216768] mtd_nandbiterrs: Inserted biterror @ 1/7 [ 37.223809] mtd_nandbiterrs: rewrite page [ 37.229569] mtd_nandbiterrs: read_page [ 37.233244] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 [ 37.236301] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.244571] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.252896] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.261227] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 [ 37.269560] mtd_nandbiterrs: Read reported 1 corrected bit errors [ 37.275795] mtd_nandbiterrs: verify_page [ 37.282075] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage [ 37.286039] mtd_nandbiterrs: Inserted biterror @ 3/7 [ 37.293080] mtd_nandbiterrs: rewrite page [ 37.298877] mtd_nandbiterrs: read_page [ 37.302531] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 [ 37.305572] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.313839] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.322169] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.330498] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 [ 37.338818] mtd_nandbiterrs: Read reported 2 corrected bit errors [ 37.345078] mtd_nandbiterrs: verify_page [ 37.351352] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage [ 37.355310] mtd_nandbiterrs: Inserted biterror @ 5/7 [ 37.362352] mtd_nandbiterrs: rewrite page [ 37.368094] mtd_nandbiterrs: read_page [ 37.371814] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0203 erased_cw:00000002 [ 37.374843] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.383111] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.391437] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.399769] qcom_snand 79b0000.spi: corrected:3 failed:0 bitflips:3 [ 37.408089] mtd_nandbiterrs: Read reported 3 corrected bit errors [ 37.414351] mtd_nandbiterrs: verify_page [ 37.420616] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage [ 37.424581] mtd_nandbiterrs: Inserted biterror @ 7/7 [ 37.431622] mtd_nandbiterrs: rewrite page [ 37.437419] mtd_nandbiterrs: read_page [ 37.441072] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0204 erased_cw:00000002 [ 37.444114] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.452380] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.460708] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.469047] qcom_snand 79b0000.spi: corrected:4 failed:0 bitflips:4 [ 37.477360] mtd_nandbiterrs: Read reported 4 corrected bit errors [ 37.483621] mtd_nandbiterrs: verify_page [ 37.489888] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage [ 37.493852] mtd_nandbiterrs: Inserted biterror @ 8/7 [ 37.500893] mtd_nandbiterrs: rewrite page [ 37.506636] mtd_nandbiterrs: read_page [ 37.510342] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0205 erased_cw:00000002 [ 37.513385] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.521652] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.529978] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.538297] qcom_snand 79b0000.spi: corrected:5 failed:0 bitflips:5 [ 37.546643] mtd_nandbiterrs: Read reported 5 corrected bit errors [ 37.552896] mtd_nandbiterrs: verify_page [ 37.559161] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage [ 37.563123] mtd_nandbiterrs: Inserted biterror @ 10/7 [ 37.570168] mtd_nandbiterrs: rewrite page [ 37.575956] mtd_nandbiterrs: read_page [ 37.579702] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0206 erased_cw:00000002 [ 37.582743] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.591010] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.599354] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.607655] qcom_snand 79b0000.spi: corrected:6 failed:0 bitflips:6 [ 37.616004] mtd_nandbiterrs: Read reported 6 corrected bit errors [ 37.622249] mtd_nandbiterrs: verify_page [ 37.628504] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage [ 37.632497] mtd_nandbiterrs: Inserted biterror @ 12/7 [ 37.639524] mtd_nandbiterrs: rewrite page [ 37.645353] mtd_nandbiterrs: read_page [ 37.649047] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0207 erased_cw:00000002 [ 37.652100] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.660367] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.668679] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.677029] qcom_snand 79b0000.spi: corrected:7 failed:0 bitflips:7 [ 37.685358] mtd_nandbiterrs: Read reported 7 corrected bit errors [ 37.691607] mtd_nandbiterrs: verify_page [ 37.697861] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage [ 37.701852] mtd_nandbiterrs: Inserted biterror @ 14/7 [ 37.708867] mtd_nandbiterrs: rewrite page [ 37.714683] mtd_nandbiterrs: read_page [ 37.718397] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0208 erased_cw:00000002 [ 37.721478] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.729718] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.738037] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.746433] qcom_snand 79b0000.spi: corrected:8 failed:0 bitflips:8 [ 37.754719] mtd_nandbiterrs: Read reported 8 corrected bit errors [ 37.760972] mtd_nandbiterrs: verify_page [ 37.767218] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage [ 37.771214] mtd_nandbiterrs: Inserted biterror @ 17/7 [ 37.778225] mtd_nandbiterrs: rewrite page [ 37.784054] mtd_nandbiterrs: read_page [ 37.787754] qcom_snand 79b0000.spi: cw[0] flash:00003030 buffer:00ff0301 erased_cw:00000002 [ 37.790836] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 [ 37.799076] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 [ 37.807395] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 [ 37.815743] qcom_snand 79b0000.spi: corrected:0 failed:1 bitflips:8 [ 37.824073] mtd_nandbiterrs: error: read failed at 0x0 [ 37.830321] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 [ 37.838993] mtd_nandbiterrs: finished successfully. [ 37.843068] ================================================== Interestingly enough, it reports the correct number of bit errors now. For me it seems, that the hardware reports the number of the corrected *bytes* instead of the corrected *bits*. I can't figure out whether this is a configuration problem only, or it is a hardware limitation. Nevertheless, it is possible that I'm entirely wrong about this, since I have no documentation for the hardware. Maybe Alam has some ideas about what could be wrong. Regards, Gabor
On 12/05/2025 at 22:19:05 +02, Gabor Juhos <j4g8y7@gmail.com> wrote: > 2025. 05. 12. 10:32 keltezéssel, Miquel Raynal írta: >> On 05/05/2025 at 15:21:52 +02, Gabor Juhos <j4g8y7@gmail.com> wrote: >> >>> 2025. 05. 05. 13:17 keltezéssel, Md Sadre Alam írta: >>>> >>>> >>> > > [...] > >>> [ 48.940586] ================================================== >>> [ 48.941112] mtd_nandbiterrs: MTD device: 0 >>> [ 48.946811] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, >>> page=2048, oob=128 >>> [ 48.950837] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes >>> [ 48.959448] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 >>> [ 48.969014] mtd_nandbiterrs: incremental biterrors test >>> [ 48.971596] mtd_nandbiterrs: write_page >>> [ 48.977594] mtd_nandbiterrs: rewrite page >>> [ 48.981277] mtd_nandbiterrs: read_page >>> [ 48.985247] mtd_nandbiterrs: verify_page >>> [ 48.988269] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage >>> [ 48.992327] mtd_nandbiterrs: Inserted biterror @ 0/5 >>> [ 48.999428] mtd_nandbiterrs: rewrite page >>> [ 49.005508] mtd_nandbiterrs: read_page >>> [ 49.008836] mtd_nandbiterrs: Read reported 1 corrected bit errors >>> [ 49.011858] mtd_nandbiterrs: verify_page >>> [ 49.018061] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage >>> [ 49.022015] mtd_nandbiterrs: Inserted biterror @ 0/2 >>> [ 49.029058] mtd_nandbiterrs: rewrite page >>> [ 49.034848] mtd_nandbiterrs: read_page >>> [ 49.038516] mtd_nandbiterrs: Read reported 1 corrected bit errors >>> [ 49.041545] mtd_nandbiterrs: verify_page >>> [ 49.047755] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage >>> [ 49.051702] mtd_nandbiterrs: Inserted biterror @ 0/0 >>> [ 49.058760] mtd_nandbiterrs: rewrite page >>> [ 49.064565] mtd_nandbiterrs: read_page >>> [ 49.068203] mtd_nandbiterrs: Read reported 1 corrected bit errors >>> [ 49.071232] mtd_nandbiterrs: verify_page >>> [ 49.077432] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage >>> [ 49.081389] mtd_nandbiterrs: Inserted biterror @ 1/7 >>> [ 49.088432] mtd_nandbiterrs: rewrite page >>> [ 49.094197] mtd_nandbiterrs: read_page >>> [ 49.097889] mtd_nandbiterrs: Read reported 2 corrected bit errors >>> [ 49.100919] mtd_nandbiterrs: verify_page >>> [ 49.107121] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage >>> [ 49.111077] mtd_nandbiterrs: Inserted biterror @ 1/5 >>> [ 49.118137] mtd_nandbiterrs: rewrite page >>> [ 49.123892] mtd_nandbiterrs: read_page >>> [ 49.127576] mtd_nandbiterrs: Read reported 2 corrected bit errors >>> [ 49.130608] mtd_nandbiterrs: verify_page >>> [ 49.136808] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage >>> [ 49.140764] mtd_nandbiterrs: Inserted biterror @ 1/2 >>> [ 49.147807] mtd_nandbiterrs: rewrite page >>> [ 49.153607] mtd_nandbiterrs: read_page >>> [ 49.157268] mtd_nandbiterrs: Read reported 2 corrected bit errors >>> [ 49.160294] mtd_nandbiterrs: verify_page >>> [ 49.166496] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage >>> [ 49.170452] mtd_nandbiterrs: Inserted biterror @ 1/0 >>> [ 49.177498] mtd_nandbiterrs: rewrite page >>> [ 49.183253] mtd_nandbiterrs: read_page >>> [ 49.186974] mtd_nandbiterrs: Read reported 2 corrected bit errors >>> [ 49.189983] mtd_nandbiterrs: verify_page >>> [ 49.196194] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage >>> [ 49.200140] mtd_nandbiterrs: Inserted biterror @ 2/6 >>> [ 49.207182] mtd_nandbiterrs: rewrite page >>> [ 49.212895] mtd_nandbiterrs: read_page >>> [ 49.216671] mtd_nandbiterrs: Read reported 3 corrected bit errors >>> [ 49.219670] mtd_nandbiterrs: verify_page >>> [ 49.225872] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage >>> [ 49.229827] mtd_nandbiterrs: Inserted biterror @ 2/5 >>> [ 49.236871] mtd_nandbiterrs: rewrite page >>> [ 49.242629] mtd_nandbiterrs: read_page >>> [ 49.246348] mtd_nandbiterrs: error: read failed at 0x0 >>> [ 49.249356] mtd_nandbiterrs: After 9 biterrors per subpage, read reported >>> error -74 >>> [ 49.257958] mtd_nandbiterrs: finished successfully. >>> [ 49.262029] ================================================== >>> # >> >> This is not the intended behavior. The reporting is wrong and should >> report an increasing number of bitflips instead of 1, 1, 1, 2, 2, 2, 2, >> 3. >> >> With this behavior, wear levelling will not work correctly. >> >> This is not related to Gabor's changes, but I believe this should be >> updated otherwise it does not make much sense to increase the strength. > > It still makes some sense. For example, the bootloader on my board uses 8 bits > strength when it handles the NAND flash. Without supporting that, the kernel > can't read the data written by the bootloader and vice versa. > >> Gabor, can you look into it? Both patches look fine otherwise, thanks a >> lot! > > I have checked it. According to the code, the driver reads the reported values > from a hardware register. > > Here is the result of another test but i have added some debug code to the > driver so the output contains the hardware register values: > > # insmod mtd_nandbiterrs dev=0 > [ 64.791395] > [ 64.791423] ================================================== > [ 64.791950] mtd_nandbiterrs: MTD device: 0 > [ 64.797592] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 > [ 64.801779] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes > [ 64.810313] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 > [ 64.820832] mtd_nandbiterrs: incremental biterrors test > [ 64.822452] mtd_nandbiterrs: write_page > [ 64.828511] mtd_nandbiterrs: rewrite page > [ 64.832270] mtd_nandbiterrs: read_page > [ 64.836184] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0200 erased_cw:00000002 > [ 64.839091] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 64.847364] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 64.855694] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 64.864020] qcom_snand 79b0000.spi: corrected:0 failed:0 bitflips:0 > [ 64.872349] mtd_nandbiterrs: verify_page > [ 64.878598] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage > [ 64.882760] mtd_nandbiterrs: Inserted biterror @ 0/5 > [ 64.889793] mtd_nandbiterrs: rewrite page > [ 64.895541] mtd_nandbiterrs: read_page > [ 64.899228] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 > [ 64.902282] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 64.910549] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 64.918860] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 64.927206] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 > [ 64.935552] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 64.941789] mtd_nandbiterrs: verify_page > [ 64.948043] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage > [ 64.952042] mtd_nandbiterrs: Inserted biterror @ 0/2 > [ 64.959048] mtd_nandbiterrs: rewrite page > [ 64.964815] mtd_nandbiterrs: read_page > [ 64.968490] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 > [ 64.971586] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 64.979814] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 64.988131] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 64.996481] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 > [ 65.004810] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 65.011059] mtd_nandbiterrs: verify_page > [ 65.017313] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage > [ 65.021307] mtd_nandbiterrs: Inserted biterror @ 0/0 > [ 65.028319] mtd_nandbiterrs: rewrite page > [ 65.034131] mtd_nandbiterrs: read_page > [ 65.037862] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 > [ 65.040844] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 65.049069] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 65.057418] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 65.065763] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 > [ 65.074082] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 65.080341] mtd_nandbiterrs: verify_page > [ 65.086584] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage > [ 65.090574] mtd_nandbiterrs: Inserted biterror @ 1/7 > [ 65.097589] mtd_nandbiterrs: rewrite page > [ 65.103374] mtd_nandbiterrs: read_page > [ 65.107030] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 > [ 65.110120] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 65.118340] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 65.126689] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 65.135032] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 > [ 65.143357] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 65.149611] mtd_nandbiterrs: verify_page > [ 65.155855] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage > [ 65.159844] mtd_nandbiterrs: Inserted biterror @ 1/5 > [ 65.166860] mtd_nandbiterrs: rewrite page > [ 65.172645] mtd_nandbiterrs: read_page > [ 65.176301] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 > [ 65.179389] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 65.187611] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 65.195961] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 65.204289] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 > [ 65.212623] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 65.218858] mtd_nandbiterrs: verify_page > [ 65.225139] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage > [ 65.229102] mtd_nandbiterrs: Inserted biterror @ 1/2 > [ 65.236147] mtd_nandbiterrs: rewrite page > [ 65.241899] mtd_nandbiterrs: read_page > [ 65.245572] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 > [ 65.248635] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 65.256902] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 65.265234] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 65.273561] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 > [ 65.281895] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 65.288129] mtd_nandbiterrs: verify_page > [ 65.294408] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage > [ 65.298373] mtd_nandbiterrs: Inserted biterror @ 1/0 > [ 65.305413] mtd_nandbiterrs: rewrite page > [ 65.311170] mtd_nandbiterrs: read_page > [ 65.314843] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 > [ 65.317906] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 65.326170] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 65.334501] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 65.342833] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 > [ 65.351164] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 65.357399] mtd_nandbiterrs: verify_page > [ 65.363680] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage > [ 65.367643] mtd_nandbiterrs: Inserted biterror @ 2/6 > [ 65.374684] mtd_nandbiterrs: rewrite page > [ 65.380445] mtd_nandbiterrs: read_page > [ 65.384112] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0203 erased_cw:00000002 > [ 65.387177] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 65.395445] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 65.403769] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 65.412103] qcom_snand 79b0000.spi: corrected:3 failed:0 bitflips:3 > [ 65.420436] mtd_nandbiterrs: Read reported 3 corrected bit errors > [ 65.426671] mtd_nandbiterrs: verify_page > [ 65.432950] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage > [ 65.436915] mtd_nandbiterrs: Inserted biterror @ 2/5 > [ 65.443958] mtd_nandbiterrs: rewrite page > [ 65.449719] mtd_nandbiterrs: read_page > [ 65.453386] qcom_snand 79b0000.spi: cw[0] flash:00003030 buffer:00ff0301 erased_cw:00000002 > [ 65.456448] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 65.464715] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 65.473041] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 65.481374] qcom_snand 79b0000.spi: corrected:0 failed:1 bitflips:3 > [ 65.489706] mtd_nandbiterrs: error: read failed at 0x0 > [ 65.495941] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 > [ 65.504609] mtd_nandbiterrs: finished successfully. > [ 65.508700] ================================================== > > > Basically, the driver reads the page as 4 codewords along with reading the > register values after each. The reported values are coming from the low > 5 bits of the 'buffer' values printed above. The layout of the register is > barely documented in the driver, so the exact meaning of the bits is unknown. > > Despite that, I had an idea, so I have changed the code in the nandbiterrs > module to insert only single bit error into a given byte. By doing the test > with the modified module results in the following: > > # insmod mtd_nandbiterrs dev=0 > [ 37.125416] > [ 37.125444] ================================================== > [ 37.125970] mtd_nandbiterrs: MTD device: 0 > [ 37.131764] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 > [ 37.135695] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes > [ 37.144314] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 > [ 37.155047] mtd_nandbiterrs: incremental biterrors test > [ 37.156481] mtd_nandbiterrs: write_page > [ 37.162518] mtd_nandbiterrs: rewrite page > [ 37.166298] mtd_nandbiterrs: read_page > [ 37.170193] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0200 erased_cw:00000002 > [ 37.173111] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.181383] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.189708] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.198020] qcom_snand 79b0000.spi: corrected:0 failed:0 bitflips:0 > [ 37.206367] mtd_nandbiterrs: verify_page > [ 37.212631] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage > [ 37.216768] mtd_nandbiterrs: Inserted biterror @ 1/7 > [ 37.223809] mtd_nandbiterrs: rewrite page > [ 37.229569] mtd_nandbiterrs: read_page > [ 37.233244] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 > [ 37.236301] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.244571] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.252896] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.261227] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 > [ 37.269560] mtd_nandbiterrs: Read reported 1 corrected bit errors > [ 37.275795] mtd_nandbiterrs: verify_page > [ 37.282075] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage > [ 37.286039] mtd_nandbiterrs: Inserted biterror @ 3/7 > [ 37.293080] mtd_nandbiterrs: rewrite page > [ 37.298877] mtd_nandbiterrs: read_page > [ 37.302531] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 > [ 37.305572] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.313839] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.322169] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.330498] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 > [ 37.338818] mtd_nandbiterrs: Read reported 2 corrected bit errors > [ 37.345078] mtd_nandbiterrs: verify_page > [ 37.351352] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage > [ 37.355310] mtd_nandbiterrs: Inserted biterror @ 5/7 > [ 37.362352] mtd_nandbiterrs: rewrite page > [ 37.368094] mtd_nandbiterrs: read_page > [ 37.371814] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0203 erased_cw:00000002 > [ 37.374843] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.383111] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.391437] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.399769] qcom_snand 79b0000.spi: corrected:3 failed:0 bitflips:3 > [ 37.408089] mtd_nandbiterrs: Read reported 3 corrected bit errors > [ 37.414351] mtd_nandbiterrs: verify_page > [ 37.420616] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage > [ 37.424581] mtd_nandbiterrs: Inserted biterror @ 7/7 > [ 37.431622] mtd_nandbiterrs: rewrite page > [ 37.437419] mtd_nandbiterrs: read_page > [ 37.441072] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0204 erased_cw:00000002 > [ 37.444114] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.452380] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.460708] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.469047] qcom_snand 79b0000.spi: corrected:4 failed:0 bitflips:4 > [ 37.477360] mtd_nandbiterrs: Read reported 4 corrected bit errors > [ 37.483621] mtd_nandbiterrs: verify_page > [ 37.489888] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage > [ 37.493852] mtd_nandbiterrs: Inserted biterror @ 8/7 > [ 37.500893] mtd_nandbiterrs: rewrite page > [ 37.506636] mtd_nandbiterrs: read_page > [ 37.510342] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0205 erased_cw:00000002 > [ 37.513385] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.521652] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.529978] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.538297] qcom_snand 79b0000.spi: corrected:5 failed:0 bitflips:5 > [ 37.546643] mtd_nandbiterrs: Read reported 5 corrected bit errors > [ 37.552896] mtd_nandbiterrs: verify_page > [ 37.559161] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage > [ 37.563123] mtd_nandbiterrs: Inserted biterror @ 10/7 > [ 37.570168] mtd_nandbiterrs: rewrite page > [ 37.575956] mtd_nandbiterrs: read_page > [ 37.579702] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0206 erased_cw:00000002 > [ 37.582743] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.591010] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.599354] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.607655] qcom_snand 79b0000.spi: corrected:6 failed:0 bitflips:6 > [ 37.616004] mtd_nandbiterrs: Read reported 6 corrected bit errors > [ 37.622249] mtd_nandbiterrs: verify_page > [ 37.628504] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage > [ 37.632497] mtd_nandbiterrs: Inserted biterror @ 12/7 > [ 37.639524] mtd_nandbiterrs: rewrite page > [ 37.645353] mtd_nandbiterrs: read_page > [ 37.649047] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0207 erased_cw:00000002 > [ 37.652100] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.660367] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.668679] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.677029] qcom_snand 79b0000.spi: corrected:7 failed:0 bitflips:7 > [ 37.685358] mtd_nandbiterrs: Read reported 7 corrected bit errors > [ 37.691607] mtd_nandbiterrs: verify_page > [ 37.697861] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage > [ 37.701852] mtd_nandbiterrs: Inserted biterror @ 14/7 > [ 37.708867] mtd_nandbiterrs: rewrite page > [ 37.714683] mtd_nandbiterrs: read_page > [ 37.718397] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0208 erased_cw:00000002 > [ 37.721478] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.729718] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.738037] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.746433] qcom_snand 79b0000.spi: corrected:8 failed:0 bitflips:8 > [ 37.754719] mtd_nandbiterrs: Read reported 8 corrected bit errors > [ 37.760972] mtd_nandbiterrs: verify_page > [ 37.767218] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage > [ 37.771214] mtd_nandbiterrs: Inserted biterror @ 17/7 > [ 37.778225] mtd_nandbiterrs: rewrite page > [ 37.784054] mtd_nandbiterrs: read_page > [ 37.787754] qcom_snand 79b0000.spi: cw[0] flash:00003030 buffer:00ff0301 erased_cw:00000002 > [ 37.790836] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 > [ 37.799076] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 > [ 37.807395] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 > [ 37.815743] qcom_snand 79b0000.spi: corrected:0 failed:1 bitflips:8 > [ 37.824073] mtd_nandbiterrs: error: read failed at 0x0 > [ 37.830321] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 > [ 37.838993] mtd_nandbiterrs: finished successfully. > [ 37.843068] ================================================== > > Interestingly enough, it reports the correct number of bit errors now. > For me it seems, that the hardware reports the number of the corrected > *bytes* instead of the corrected *bits*. I doubt that, nobody counts bytes of errors. You results are surprising. I initially though in favour of a software bug, but then it looks even weirder than that. Alam? Thanks, Miquèl
On 5/13/2025 1:02 PM, Miquel Raynal wrote: > On 12/05/2025 at 22:19:05 +02, Gabor Juhos <j4g8y7@gmail.com> wrote: > >> 2025. 05. 12. 10:32 keltezéssel, Miquel Raynal írta: >>> On 05/05/2025 at 15:21:52 +02, Gabor Juhos <j4g8y7@gmail.com> wrote: >>> >>>> 2025. 05. 05. 13:17 keltezéssel, Md Sadre Alam írta: >>>>> >>>>> >>>> >> >> [...] >> >>>> [ 48.940586] ================================================== >>>> [ 48.941112] mtd_nandbiterrs: MTD device: 0 >>>> [ 48.946811] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, >>>> page=2048, oob=128 >>>> [ 48.950837] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes >>>> [ 48.959448] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 >>>> [ 48.969014] mtd_nandbiterrs: incremental biterrors test >>>> [ 48.971596] mtd_nandbiterrs: write_page >>>> [ 48.977594] mtd_nandbiterrs: rewrite page >>>> [ 48.981277] mtd_nandbiterrs: read_page >>>> [ 48.985247] mtd_nandbiterrs: verify_page >>>> [ 48.988269] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage >>>> [ 48.992327] mtd_nandbiterrs: Inserted biterror @ 0/5 >>>> [ 48.999428] mtd_nandbiterrs: rewrite page >>>> [ 49.005508] mtd_nandbiterrs: read_page >>>> [ 49.008836] mtd_nandbiterrs: Read reported 1 corrected bit errors >>>> [ 49.011858] mtd_nandbiterrs: verify_page >>>> [ 49.018061] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage >>>> [ 49.022015] mtd_nandbiterrs: Inserted biterror @ 0/2 >>>> [ 49.029058] mtd_nandbiterrs: rewrite page >>>> [ 49.034848] mtd_nandbiterrs: read_page >>>> [ 49.038516] mtd_nandbiterrs: Read reported 1 corrected bit errors >>>> [ 49.041545] mtd_nandbiterrs: verify_page >>>> [ 49.047755] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage >>>> [ 49.051702] mtd_nandbiterrs: Inserted biterror @ 0/0 >>>> [ 49.058760] mtd_nandbiterrs: rewrite page >>>> [ 49.064565] mtd_nandbiterrs: read_page >>>> [ 49.068203] mtd_nandbiterrs: Read reported 1 corrected bit errors >>>> [ 49.071232] mtd_nandbiterrs: verify_page >>>> [ 49.077432] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage >>>> [ 49.081389] mtd_nandbiterrs: Inserted biterror @ 1/7 >>>> [ 49.088432] mtd_nandbiterrs: rewrite page >>>> [ 49.094197] mtd_nandbiterrs: read_page >>>> [ 49.097889] mtd_nandbiterrs: Read reported 2 corrected bit errors >>>> [ 49.100919] mtd_nandbiterrs: verify_page >>>> [ 49.107121] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage >>>> [ 49.111077] mtd_nandbiterrs: Inserted biterror @ 1/5 >>>> [ 49.118137] mtd_nandbiterrs: rewrite page >>>> [ 49.123892] mtd_nandbiterrs: read_page >>>> [ 49.127576] mtd_nandbiterrs: Read reported 2 corrected bit errors >>>> [ 49.130608] mtd_nandbiterrs: verify_page >>>> [ 49.136808] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage >>>> [ 49.140764] mtd_nandbiterrs: Inserted biterror @ 1/2 >>>> [ 49.147807] mtd_nandbiterrs: rewrite page >>>> [ 49.153607] mtd_nandbiterrs: read_page >>>> [ 49.157268] mtd_nandbiterrs: Read reported 2 corrected bit errors >>>> [ 49.160294] mtd_nandbiterrs: verify_page >>>> [ 49.166496] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage >>>> [ 49.170452] mtd_nandbiterrs: Inserted biterror @ 1/0 >>>> [ 49.177498] mtd_nandbiterrs: rewrite page >>>> [ 49.183253] mtd_nandbiterrs: read_page >>>> [ 49.186974] mtd_nandbiterrs: Read reported 2 corrected bit errors >>>> [ 49.189983] mtd_nandbiterrs: verify_page >>>> [ 49.196194] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage >>>> [ 49.200140] mtd_nandbiterrs: Inserted biterror @ 2/6 >>>> [ 49.207182] mtd_nandbiterrs: rewrite page >>>> [ 49.212895] mtd_nandbiterrs: read_page >>>> [ 49.216671] mtd_nandbiterrs: Read reported 3 corrected bit errors >>>> [ 49.219670] mtd_nandbiterrs: verify_page >>>> [ 49.225872] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage >>>> [ 49.229827] mtd_nandbiterrs: Inserted biterror @ 2/5 >>>> [ 49.236871] mtd_nandbiterrs: rewrite page >>>> [ 49.242629] mtd_nandbiterrs: read_page >>>> [ 49.246348] mtd_nandbiterrs: error: read failed at 0x0 >>>> [ 49.249356] mtd_nandbiterrs: After 9 biterrors per subpage, read reported >>>> error -74 >>>> [ 49.257958] mtd_nandbiterrs: finished successfully. >>>> [ 49.262029] ================================================== >>>> # >>> >>> This is not the intended behavior. The reporting is wrong and should >>> report an increasing number of bitflips instead of 1, 1, 1, 2, 2, 2, 2, >>> 3. >>> >>> With this behavior, wear levelling will not work correctly. >>> >>> This is not related to Gabor's changes, but I believe this should be >>> updated otherwise it does not make much sense to increase the strength. >> >> It still makes some sense. For example, the bootloader on my board uses 8 bits >> strength when it handles the NAND flash. Without supporting that, the kernel >> can't read the data written by the bootloader and vice versa. >> >>> Gabor, can you look into it? Both patches look fine otherwise, thanks a >>> lot! >> >> I have checked it. According to the code, the driver reads the reported values >> from a hardware register. >> >> Here is the result of another test but i have added some debug code to the >> driver so the output contains the hardware register values: >> >> # insmod mtd_nandbiterrs dev=0 >> [ 64.791395] >> [ 64.791423] ================================================== >> [ 64.791950] mtd_nandbiterrs: MTD device: 0 >> [ 64.797592] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 >> [ 64.801779] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes >> [ 64.810313] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 >> [ 64.820832] mtd_nandbiterrs: incremental biterrors test >> [ 64.822452] mtd_nandbiterrs: write_page >> [ 64.828511] mtd_nandbiterrs: rewrite page >> [ 64.832270] mtd_nandbiterrs: read_page >> [ 64.836184] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0200 erased_cw:00000002 >> [ 64.839091] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 64.847364] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 64.855694] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 64.864020] qcom_snand 79b0000.spi: corrected:0 failed:0 bitflips:0 >> [ 64.872349] mtd_nandbiterrs: verify_page >> [ 64.878598] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage >> [ 64.882760] mtd_nandbiterrs: Inserted biterror @ 0/5 >> [ 64.889793] mtd_nandbiterrs: rewrite page >> [ 64.895541] mtd_nandbiterrs: read_page >> [ 64.899228] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 >> [ 64.902282] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 64.910549] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 64.918860] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 64.927206] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 >> [ 64.935552] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 64.941789] mtd_nandbiterrs: verify_page >> [ 64.948043] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage >> [ 64.952042] mtd_nandbiterrs: Inserted biterror @ 0/2 >> [ 64.959048] mtd_nandbiterrs: rewrite page >> [ 64.964815] mtd_nandbiterrs: read_page >> [ 64.968490] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 >> [ 64.971586] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 64.979814] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 64.988131] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 64.996481] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 >> [ 65.004810] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 65.011059] mtd_nandbiterrs: verify_page >> [ 65.017313] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage >> [ 65.021307] mtd_nandbiterrs: Inserted biterror @ 0/0 >> [ 65.028319] mtd_nandbiterrs: rewrite page >> [ 65.034131] mtd_nandbiterrs: read_page >> [ 65.037862] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 >> [ 65.040844] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.049069] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.057418] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.065763] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 >> [ 65.074082] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 65.080341] mtd_nandbiterrs: verify_page >> [ 65.086584] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage >> [ 65.090574] mtd_nandbiterrs: Inserted biterror @ 1/7 >> [ 65.097589] mtd_nandbiterrs: rewrite page >> [ 65.103374] mtd_nandbiterrs: read_page >> [ 65.107030] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 65.110120] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.118340] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.126689] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.135032] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 65.143357] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 65.149611] mtd_nandbiterrs: verify_page >> [ 65.155855] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage >> [ 65.159844] mtd_nandbiterrs: Inserted biterror @ 1/5 >> [ 65.166860] mtd_nandbiterrs: rewrite page >> [ 65.172645] mtd_nandbiterrs: read_page >> [ 65.176301] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 65.179389] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.187611] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.195961] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.204289] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 65.212623] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 65.218858] mtd_nandbiterrs: verify_page >> [ 65.225139] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage >> [ 65.229102] mtd_nandbiterrs: Inserted biterror @ 1/2 >> [ 65.236147] mtd_nandbiterrs: rewrite page >> [ 65.241899] mtd_nandbiterrs: read_page >> [ 65.245572] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 65.248635] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.256902] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.265234] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.273561] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 65.281895] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 65.288129] mtd_nandbiterrs: verify_page >> [ 65.294408] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage >> [ 65.298373] mtd_nandbiterrs: Inserted biterror @ 1/0 >> [ 65.305413] mtd_nandbiterrs: rewrite page >> [ 65.311170] mtd_nandbiterrs: read_page >> [ 65.314843] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 65.317906] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.326170] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.334501] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.342833] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 65.351164] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 65.357399] mtd_nandbiterrs: verify_page >> [ 65.363680] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage >> [ 65.367643] mtd_nandbiterrs: Inserted biterror @ 2/6 >> [ 65.374684] mtd_nandbiterrs: rewrite page >> [ 65.380445] mtd_nandbiterrs: read_page >> [ 65.384112] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0203 erased_cw:00000002 >> [ 65.387177] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.395445] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.403769] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.412103] qcom_snand 79b0000.spi: corrected:3 failed:0 bitflips:3 >> [ 65.420436] mtd_nandbiterrs: Read reported 3 corrected bit errors >> [ 65.426671] mtd_nandbiterrs: verify_page >> [ 65.432950] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage >> [ 65.436915] mtd_nandbiterrs: Inserted biterror @ 2/5 >> [ 65.443958] mtd_nandbiterrs: rewrite page >> [ 65.449719] mtd_nandbiterrs: read_page >> [ 65.453386] qcom_snand 79b0000.spi: cw[0] flash:00003030 buffer:00ff0301 erased_cw:00000002 >> [ 65.456448] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.464715] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.473041] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.481374] qcom_snand 79b0000.spi: corrected:0 failed:1 bitflips:3 >> [ 65.489706] mtd_nandbiterrs: error: read failed at 0x0 >> [ 65.495941] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 >> [ 65.504609] mtd_nandbiterrs: finished successfully. >> [ 65.508700] ================================================== >> >> >> Basically, the driver reads the page as 4 codewords along with reading the >> register values after each. The reported values are coming from the low >> 5 bits of the 'buffer' values printed above. The layout of the register is >> barely documented in the driver, so the exact meaning of the bits is unknown. >> >> Despite that, I had an idea, so I have changed the code in the nandbiterrs >> module to insert only single bit error into a given byte. By doing the test >> with the modified module results in the following: >> >> # insmod mtd_nandbiterrs dev=0 >> [ 37.125416] >> [ 37.125444] ================================================== >> [ 37.125970] mtd_nandbiterrs: MTD device: 0 >> [ 37.131764] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 >> [ 37.135695] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes >> [ 37.144314] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 >> [ 37.155047] mtd_nandbiterrs: incremental biterrors test >> [ 37.156481] mtd_nandbiterrs: write_page >> [ 37.162518] mtd_nandbiterrs: rewrite page >> [ 37.166298] mtd_nandbiterrs: read_page >> [ 37.170193] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0200 erased_cw:00000002 >> [ 37.173111] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.181383] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.189708] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.198020] qcom_snand 79b0000.spi: corrected:0 failed:0 bitflips:0 >> [ 37.206367] mtd_nandbiterrs: verify_page >> [ 37.212631] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage >> [ 37.216768] mtd_nandbiterrs: Inserted biterror @ 1/7 >> [ 37.223809] mtd_nandbiterrs: rewrite page >> [ 37.229569] mtd_nandbiterrs: read_page >> [ 37.233244] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 >> [ 37.236301] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.244571] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.252896] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.261227] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 >> [ 37.269560] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 37.275795] mtd_nandbiterrs: verify_page >> [ 37.282075] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage >> [ 37.286039] mtd_nandbiterrs: Inserted biterror @ 3/7 >> [ 37.293080] mtd_nandbiterrs: rewrite page >> [ 37.298877] mtd_nandbiterrs: read_page >> [ 37.302531] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 37.305572] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.313839] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.322169] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.330498] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 37.338818] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 37.345078] mtd_nandbiterrs: verify_page >> [ 37.351352] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage >> [ 37.355310] mtd_nandbiterrs: Inserted biterror @ 5/7 >> [ 37.362352] mtd_nandbiterrs: rewrite page >> [ 37.368094] mtd_nandbiterrs: read_page >> [ 37.371814] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0203 erased_cw:00000002 >> [ 37.374843] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.383111] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.391437] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.399769] qcom_snand 79b0000.spi: corrected:3 failed:0 bitflips:3 >> [ 37.408089] mtd_nandbiterrs: Read reported 3 corrected bit errors >> [ 37.414351] mtd_nandbiterrs: verify_page >> [ 37.420616] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage >> [ 37.424581] mtd_nandbiterrs: Inserted biterror @ 7/7 >> [ 37.431622] mtd_nandbiterrs: rewrite page >> [ 37.437419] mtd_nandbiterrs: read_page >> [ 37.441072] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0204 erased_cw:00000002 >> [ 37.444114] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.452380] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.460708] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.469047] qcom_snand 79b0000.spi: corrected:4 failed:0 bitflips:4 >> [ 37.477360] mtd_nandbiterrs: Read reported 4 corrected bit errors >> [ 37.483621] mtd_nandbiterrs: verify_page >> [ 37.489888] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage >> [ 37.493852] mtd_nandbiterrs: Inserted biterror @ 8/7 >> [ 37.500893] mtd_nandbiterrs: rewrite page >> [ 37.506636] mtd_nandbiterrs: read_page >> [ 37.510342] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0205 erased_cw:00000002 >> [ 37.513385] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.521652] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.529978] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.538297] qcom_snand 79b0000.spi: corrected:5 failed:0 bitflips:5 >> [ 37.546643] mtd_nandbiterrs: Read reported 5 corrected bit errors >> [ 37.552896] mtd_nandbiterrs: verify_page >> [ 37.559161] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage >> [ 37.563123] mtd_nandbiterrs: Inserted biterror @ 10/7 >> [ 37.570168] mtd_nandbiterrs: rewrite page >> [ 37.575956] mtd_nandbiterrs: read_page >> [ 37.579702] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0206 erased_cw:00000002 >> [ 37.582743] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.591010] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.599354] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.607655] qcom_snand 79b0000.spi: corrected:6 failed:0 bitflips:6 >> [ 37.616004] mtd_nandbiterrs: Read reported 6 corrected bit errors >> [ 37.622249] mtd_nandbiterrs: verify_page >> [ 37.628504] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage >> [ 37.632497] mtd_nandbiterrs: Inserted biterror @ 12/7 >> [ 37.639524] mtd_nandbiterrs: rewrite page >> [ 37.645353] mtd_nandbiterrs: read_page >> [ 37.649047] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0207 erased_cw:00000002 >> [ 37.652100] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.660367] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.668679] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.677029] qcom_snand 79b0000.spi: corrected:7 failed:0 bitflips:7 >> [ 37.685358] mtd_nandbiterrs: Read reported 7 corrected bit errors >> [ 37.691607] mtd_nandbiterrs: verify_page >> [ 37.697861] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage >> [ 37.701852] mtd_nandbiterrs: Inserted biterror @ 14/7 >> [ 37.708867] mtd_nandbiterrs: rewrite page >> [ 37.714683] mtd_nandbiterrs: read_page >> [ 37.718397] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0208 erased_cw:00000002 >> [ 37.721478] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.729718] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.738037] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.746433] qcom_snand 79b0000.spi: corrected:8 failed:0 bitflips:8 >> [ 37.754719] mtd_nandbiterrs: Read reported 8 corrected bit errors >> [ 37.760972] mtd_nandbiterrs: verify_page >> [ 37.767218] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage >> [ 37.771214] mtd_nandbiterrs: Inserted biterror @ 17/7 >> [ 37.778225] mtd_nandbiterrs: rewrite page >> [ 37.784054] mtd_nandbiterrs: read_page >> [ 37.787754] qcom_snand 79b0000.spi: cw[0] flash:00003030 buffer:00ff0301 erased_cw:00000002 >> [ 37.790836] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.799076] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.807395] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.815743] qcom_snand 79b0000.spi: corrected:0 failed:1 bitflips:8 >> [ 37.824073] mtd_nandbiterrs: error: read failed at 0x0 >> [ 37.830321] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 >> [ 37.838993] mtd_nandbiterrs: finished successfully. >> [ 37.843068] ================================================== >> >> Interestingly enough, it reports the correct number of bit errors now. >> For me it seems, that the hardware reports the number of the corrected >> *bytes* instead of the corrected *bits*. > > I doubt that, nobody counts bytes of errors. > > You results are surprising. I initially though in favour of a software > bug, but then it looks even weirder than that. Alam? I am checking with HW team, will update with details once get the input. Thanks, Alam.
On 5/13/2025 1:02 PM, Miquel Raynal wrote: > On 12/05/2025 at 22:19:05 +02, Gabor Juhos <j4g8y7@gmail.com> wrote: > >> 2025. 05. 12. 10:32 keltezéssel, Miquel Raynal írta: >>> On 05/05/2025 at 15:21:52 +02, Gabor Juhos <j4g8y7@gmail.com> wrote: >>> >>>> 2025. 05. 05. 13:17 keltezéssel, Md Sadre Alam írta: >>>>> >>>>> >>>> >> >> [...] >> >>>> [ 48.940586] ================================================== >>>> [ 48.941112] mtd_nandbiterrs: MTD device: 0 >>>> [ 48.946811] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, >>>> page=2048, oob=128 >>>> [ 48.950837] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes >>>> [ 48.959448] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 >>>> [ 48.969014] mtd_nandbiterrs: incremental biterrors test >>>> [ 48.971596] mtd_nandbiterrs: write_page >>>> [ 48.977594] mtd_nandbiterrs: rewrite page >>>> [ 48.981277] mtd_nandbiterrs: read_page >>>> [ 48.985247] mtd_nandbiterrs: verify_page >>>> [ 48.988269] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage >>>> [ 48.992327] mtd_nandbiterrs: Inserted biterror @ 0/5 >>>> [ 48.999428] mtd_nandbiterrs: rewrite page >>>> [ 49.005508] mtd_nandbiterrs: read_page >>>> [ 49.008836] mtd_nandbiterrs: Read reported 1 corrected bit errors >>>> [ 49.011858] mtd_nandbiterrs: verify_page >>>> [ 49.018061] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage >>>> [ 49.022015] mtd_nandbiterrs: Inserted biterror @ 0/2 >>>> [ 49.029058] mtd_nandbiterrs: rewrite page >>>> [ 49.034848] mtd_nandbiterrs: read_page >>>> [ 49.038516] mtd_nandbiterrs: Read reported 1 corrected bit errors >>>> [ 49.041545] mtd_nandbiterrs: verify_page >>>> [ 49.047755] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage >>>> [ 49.051702] mtd_nandbiterrs: Inserted biterror @ 0/0 >>>> [ 49.058760] mtd_nandbiterrs: rewrite page >>>> [ 49.064565] mtd_nandbiterrs: read_page >>>> [ 49.068203] mtd_nandbiterrs: Read reported 1 corrected bit errors >>>> [ 49.071232] mtd_nandbiterrs: verify_page >>>> [ 49.077432] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage >>>> [ 49.081389] mtd_nandbiterrs: Inserted biterror @ 1/7 >>>> [ 49.088432] mtd_nandbiterrs: rewrite page >>>> [ 49.094197] mtd_nandbiterrs: read_page >>>> [ 49.097889] mtd_nandbiterrs: Read reported 2 corrected bit errors >>>> [ 49.100919] mtd_nandbiterrs: verify_page >>>> [ 49.107121] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage >>>> [ 49.111077] mtd_nandbiterrs: Inserted biterror @ 1/5 >>>> [ 49.118137] mtd_nandbiterrs: rewrite page >>>> [ 49.123892] mtd_nandbiterrs: read_page >>>> [ 49.127576] mtd_nandbiterrs: Read reported 2 corrected bit errors >>>> [ 49.130608] mtd_nandbiterrs: verify_page >>>> [ 49.136808] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage >>>> [ 49.140764] mtd_nandbiterrs: Inserted biterror @ 1/2 >>>> [ 49.147807] mtd_nandbiterrs: rewrite page >>>> [ 49.153607] mtd_nandbiterrs: read_page >>>> [ 49.157268] mtd_nandbiterrs: Read reported 2 corrected bit errors >>>> [ 49.160294] mtd_nandbiterrs: verify_page >>>> [ 49.166496] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage >>>> [ 49.170452] mtd_nandbiterrs: Inserted biterror @ 1/0 >>>> [ 49.177498] mtd_nandbiterrs: rewrite page >>>> [ 49.183253] mtd_nandbiterrs: read_page >>>> [ 49.186974] mtd_nandbiterrs: Read reported 2 corrected bit errors >>>> [ 49.189983] mtd_nandbiterrs: verify_page >>>> [ 49.196194] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage >>>> [ 49.200140] mtd_nandbiterrs: Inserted biterror @ 2/6 >>>> [ 49.207182] mtd_nandbiterrs: rewrite page >>>> [ 49.212895] mtd_nandbiterrs: read_page >>>> [ 49.216671] mtd_nandbiterrs: Read reported 3 corrected bit errors >>>> [ 49.219670] mtd_nandbiterrs: verify_page >>>> [ 49.225872] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage >>>> [ 49.229827] mtd_nandbiterrs: Inserted biterror @ 2/5 >>>> [ 49.236871] mtd_nandbiterrs: rewrite page >>>> [ 49.242629] mtd_nandbiterrs: read_page >>>> [ 49.246348] mtd_nandbiterrs: error: read failed at 0x0 >>>> [ 49.249356] mtd_nandbiterrs: After 9 biterrors per subpage, read reported >>>> error -74 >>>> [ 49.257958] mtd_nandbiterrs: finished successfully. >>>> [ 49.262029] ================================================== >>>> # >>> >>> This is not the intended behavior. The reporting is wrong and should >>> report an increasing number of bitflips instead of 1, 1, 1, 2, 2, 2, 2, >>> 3. >>> >>> With this behavior, wear levelling will not work correctly. >>> >>> This is not related to Gabor's changes, but I believe this should be >>> updated otherwise it does not make much sense to increase the strength. >> >> It still makes some sense. For example, the bootloader on my board uses 8 bits >> strength when it handles the NAND flash. Without supporting that, the kernel >> can't read the data written by the bootloader and vice versa. >> >>> Gabor, can you look into it? Both patches look fine otherwise, thanks a >>> lot! >> >> I have checked it. According to the code, the driver reads the reported values >> from a hardware register. >> >> Here is the result of another test but i have added some debug code to the >> driver so the output contains the hardware register values: >> >> # insmod mtd_nandbiterrs dev=0 >> [ 64.791395] >> [ 64.791423] ================================================== >> [ 64.791950] mtd_nandbiterrs: MTD device: 0 >> [ 64.797592] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 >> [ 64.801779] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes >> [ 64.810313] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 >> [ 64.820832] mtd_nandbiterrs: incremental biterrors test >> [ 64.822452] mtd_nandbiterrs: write_page >> [ 64.828511] mtd_nandbiterrs: rewrite page >> [ 64.832270] mtd_nandbiterrs: read_page >> [ 64.836184] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0200 erased_cw:00000002 >> [ 64.839091] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 64.847364] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 64.855694] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 64.864020] qcom_snand 79b0000.spi: corrected:0 failed:0 bitflips:0 >> [ 64.872349] mtd_nandbiterrs: verify_page >> [ 64.878598] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage >> [ 64.882760] mtd_nandbiterrs: Inserted biterror @ 0/5 >> [ 64.889793] mtd_nandbiterrs: rewrite page >> [ 64.895541] mtd_nandbiterrs: read_page >> [ 64.899228] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 >> [ 64.902282] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 64.910549] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 64.918860] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 64.927206] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 >> [ 64.935552] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 64.941789] mtd_nandbiterrs: verify_page >> [ 64.948043] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage >> [ 64.952042] mtd_nandbiterrs: Inserted biterror @ 0/2 >> [ 64.959048] mtd_nandbiterrs: rewrite page >> [ 64.964815] mtd_nandbiterrs: read_page >> [ 64.968490] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 >> [ 64.971586] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 64.979814] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 64.988131] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 64.996481] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 >> [ 65.004810] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 65.011059] mtd_nandbiterrs: verify_page >> [ 65.017313] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage >> [ 65.021307] mtd_nandbiterrs: Inserted biterror @ 0/0 >> [ 65.028319] mtd_nandbiterrs: rewrite page >> [ 65.034131] mtd_nandbiterrs: read_page >> [ 65.037862] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 >> [ 65.040844] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.049069] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.057418] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.065763] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 >> [ 65.074082] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 65.080341] mtd_nandbiterrs: verify_page >> [ 65.086584] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage >> [ 65.090574] mtd_nandbiterrs: Inserted biterror @ 1/7 >> [ 65.097589] mtd_nandbiterrs: rewrite page >> [ 65.103374] mtd_nandbiterrs: read_page >> [ 65.107030] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 65.110120] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.118340] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.126689] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.135032] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 65.143357] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 65.149611] mtd_nandbiterrs: verify_page >> [ 65.155855] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage >> [ 65.159844] mtd_nandbiterrs: Inserted biterror @ 1/5 >> [ 65.166860] mtd_nandbiterrs: rewrite page >> [ 65.172645] mtd_nandbiterrs: read_page >> [ 65.176301] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 65.179389] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.187611] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.195961] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.204289] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 65.212623] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 65.218858] mtd_nandbiterrs: verify_page >> [ 65.225139] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage >> [ 65.229102] mtd_nandbiterrs: Inserted biterror @ 1/2 >> [ 65.236147] mtd_nandbiterrs: rewrite page >> [ 65.241899] mtd_nandbiterrs: read_page >> [ 65.245572] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 65.248635] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.256902] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.265234] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.273561] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 65.281895] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 65.288129] mtd_nandbiterrs: verify_page >> [ 65.294408] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage >> [ 65.298373] mtd_nandbiterrs: Inserted biterror @ 1/0 >> [ 65.305413] mtd_nandbiterrs: rewrite page >> [ 65.311170] mtd_nandbiterrs: read_page >> [ 65.314843] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 65.317906] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.326170] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.334501] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.342833] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 65.351164] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 65.357399] mtd_nandbiterrs: verify_page >> [ 65.363680] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage >> [ 65.367643] mtd_nandbiterrs: Inserted biterror @ 2/6 >> [ 65.374684] mtd_nandbiterrs: rewrite page >> [ 65.380445] mtd_nandbiterrs: read_page >> [ 65.384112] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0203 erased_cw:00000002 >> [ 65.387177] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.395445] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.403769] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.412103] qcom_snand 79b0000.spi: corrected:3 failed:0 bitflips:3 >> [ 65.420436] mtd_nandbiterrs: Read reported 3 corrected bit errors >> [ 65.426671] mtd_nandbiterrs: verify_page >> [ 65.432950] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage >> [ 65.436915] mtd_nandbiterrs: Inserted biterror @ 2/5 >> [ 65.443958] mtd_nandbiterrs: rewrite page >> [ 65.449719] mtd_nandbiterrs: read_page >> [ 65.453386] qcom_snand 79b0000.spi: cw[0] flash:00003030 buffer:00ff0301 erased_cw:00000002 >> [ 65.456448] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 65.464715] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 65.473041] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 65.481374] qcom_snand 79b0000.spi: corrected:0 failed:1 bitflips:3 >> [ 65.489706] mtd_nandbiterrs: error: read failed at 0x0 >> [ 65.495941] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 >> [ 65.504609] mtd_nandbiterrs: finished successfully. >> [ 65.508700] ================================================== >> >> >> Basically, the driver reads the page as 4 codewords along with reading the >> register values after each. The reported values are coming from the low >> 5 bits of the 'buffer' values printed above. The layout of the register is >> barely documented in the driver, so the exact meaning of the bits is unknown. >> >> Despite that, I had an idea, so I have changed the code in the nandbiterrs >> module to insert only single bit error into a given byte. By doing the test >> with the modified module results in the following: >> >> # insmod mtd_nandbiterrs dev=0 >> [ 37.125416] >> [ 37.125444] ================================================== >> [ 37.125970] mtd_nandbiterrs: MTD device: 0 >> [ 37.131764] mtd_nandbiterrs: MTD device size 268435456, eraseblock=131072, page=2048, oob=128 >> [ 37.135695] mtd_nandbiterrs: Device uses 1 subpages of 2048 bytes >> [ 37.144314] mtd_nandbiterrs: Using page=0, offset=0, eraseblock=0 >> [ 37.155047] mtd_nandbiterrs: incremental biterrors test >> [ 37.156481] mtd_nandbiterrs: write_page >> [ 37.162518] mtd_nandbiterrs: rewrite page >> [ 37.166298] mtd_nandbiterrs: read_page >> [ 37.170193] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0200 erased_cw:00000002 >> [ 37.173111] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.181383] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.189708] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.198020] qcom_snand 79b0000.spi: corrected:0 failed:0 bitflips:0 >> [ 37.206367] mtd_nandbiterrs: verify_page >> [ 37.212631] mtd_nandbiterrs: Successfully corrected 0 bit errors per subpage >> [ 37.216768] mtd_nandbiterrs: Inserted biterror @ 1/7 >> [ 37.223809] mtd_nandbiterrs: rewrite page >> [ 37.229569] mtd_nandbiterrs: read_page >> [ 37.233244] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0201 erased_cw:00000002 >> [ 37.236301] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.244571] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.252896] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.261227] qcom_snand 79b0000.spi: corrected:1 failed:0 bitflips:1 >> [ 37.269560] mtd_nandbiterrs: Read reported 1 corrected bit errors >> [ 37.275795] mtd_nandbiterrs: verify_page >> [ 37.282075] mtd_nandbiterrs: Successfully corrected 1 bit errors per subpage >> [ 37.286039] mtd_nandbiterrs: Inserted biterror @ 3/7 >> [ 37.293080] mtd_nandbiterrs: rewrite page >> [ 37.298877] mtd_nandbiterrs: read_page >> [ 37.302531] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0202 erased_cw:00000002 >> [ 37.305572] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.313839] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.322169] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.330498] qcom_snand 79b0000.spi: corrected:2 failed:0 bitflips:2 >> [ 37.338818] mtd_nandbiterrs: Read reported 2 corrected bit errors >> [ 37.345078] mtd_nandbiterrs: verify_page >> [ 37.351352] mtd_nandbiterrs: Successfully corrected 2 bit errors per subpage >> [ 37.355310] mtd_nandbiterrs: Inserted biterror @ 5/7 >> [ 37.362352] mtd_nandbiterrs: rewrite page >> [ 37.368094] mtd_nandbiterrs: read_page >> [ 37.371814] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0203 erased_cw:00000002 >> [ 37.374843] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.383111] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.391437] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.399769] qcom_snand 79b0000.spi: corrected:3 failed:0 bitflips:3 >> [ 37.408089] mtd_nandbiterrs: Read reported 3 corrected bit errors >> [ 37.414351] mtd_nandbiterrs: verify_page >> [ 37.420616] mtd_nandbiterrs: Successfully corrected 3 bit errors per subpage >> [ 37.424581] mtd_nandbiterrs: Inserted biterror @ 7/7 >> [ 37.431622] mtd_nandbiterrs: rewrite page >> [ 37.437419] mtd_nandbiterrs: read_page >> [ 37.441072] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0204 erased_cw:00000002 >> [ 37.444114] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.452380] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.460708] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.469047] qcom_snand 79b0000.spi: corrected:4 failed:0 bitflips:4 >> [ 37.477360] mtd_nandbiterrs: Read reported 4 corrected bit errors >> [ 37.483621] mtd_nandbiterrs: verify_page >> [ 37.489888] mtd_nandbiterrs: Successfully corrected 4 bit errors per subpage >> [ 37.493852] mtd_nandbiterrs: Inserted biterror @ 8/7 >> [ 37.500893] mtd_nandbiterrs: rewrite page >> [ 37.506636] mtd_nandbiterrs: read_page >> [ 37.510342] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0205 erased_cw:00000002 >> [ 37.513385] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.521652] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.529978] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.538297] qcom_snand 79b0000.spi: corrected:5 failed:0 bitflips:5 >> [ 37.546643] mtd_nandbiterrs: Read reported 5 corrected bit errors >> [ 37.552896] mtd_nandbiterrs: verify_page >> [ 37.559161] mtd_nandbiterrs: Successfully corrected 5 bit errors per subpage >> [ 37.563123] mtd_nandbiterrs: Inserted biterror @ 10/7 >> [ 37.570168] mtd_nandbiterrs: rewrite page >> [ 37.575956] mtd_nandbiterrs: read_page >> [ 37.579702] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0206 erased_cw:00000002 >> [ 37.582743] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.591010] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.599354] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.607655] qcom_snand 79b0000.spi: corrected:6 failed:0 bitflips:6 >> [ 37.616004] mtd_nandbiterrs: Read reported 6 corrected bit errors >> [ 37.622249] mtd_nandbiterrs: verify_page >> [ 37.628504] mtd_nandbiterrs: Successfully corrected 6 bit errors per subpage >> [ 37.632497] mtd_nandbiterrs: Inserted biterror @ 12/7 >> [ 37.639524] mtd_nandbiterrs: rewrite page >> [ 37.645353] mtd_nandbiterrs: read_page >> [ 37.649047] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0207 erased_cw:00000002 >> [ 37.652100] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.660367] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.668679] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.677029] qcom_snand 79b0000.spi: corrected:7 failed:0 bitflips:7 >> [ 37.685358] mtd_nandbiterrs: Read reported 7 corrected bit errors >> [ 37.691607] mtd_nandbiterrs: verify_page >> [ 37.697861] mtd_nandbiterrs: Successfully corrected 7 bit errors per subpage >> [ 37.701852] mtd_nandbiterrs: Inserted biterror @ 14/7 >> [ 37.708867] mtd_nandbiterrs: rewrite page >> [ 37.714683] mtd_nandbiterrs: read_page >> [ 37.718397] qcom_snand 79b0000.spi: cw[0] flash:00003020 buffer:00ff0208 erased_cw:00000002 >> [ 37.721478] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.729718] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.738037] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.746433] qcom_snand 79b0000.spi: corrected:8 failed:0 bitflips:8 >> [ 37.754719] mtd_nandbiterrs: Read reported 8 corrected bit errors >> [ 37.760972] mtd_nandbiterrs: verify_page >> [ 37.767218] mtd_nandbiterrs: Successfully corrected 8 bit errors per subpage >> [ 37.771214] mtd_nandbiterrs: Inserted biterror @ 17/7 >> [ 37.778225] mtd_nandbiterrs: rewrite page >> [ 37.784054] mtd_nandbiterrs: read_page >> [ 37.787754] qcom_snand 79b0000.spi: cw[0] flash:00003030 buffer:00ff0301 erased_cw:00000002 >> [ 37.790836] qcom_snand 79b0000.spi: cw[1] flash:00002020 buffer:00ff0200 erased_cw:00000002 >> [ 37.799076] qcom_snand 79b0000.spi: cw[2] flash:00001020 buffer:00ff0200 erased_cw:00000002 >> [ 37.807395] qcom_snand 79b0000.spi: cw[3] flash:00000020 buffer:00ff0200 erased_cw:00000002 >> [ 37.815743] qcom_snand 79b0000.spi: corrected:0 failed:1 bitflips:8 >> [ 37.824073] mtd_nandbiterrs: error: read failed at 0x0 >> [ 37.830321] mtd_nandbiterrs: After 9 biterrors per subpage, read reported error -74 >> [ 37.838993] mtd_nandbiterrs: finished successfully. >> [ 37.843068] ================================================== >> >> Interestingly enough, it reports the correct number of bit errors now. >> For me it seems, that the hardware reports the number of the corrected >> *bytes* instead of the corrected *bits*. > > I doubt that, nobody counts bytes of errors. > > You results are surprising. I initially though in favour of a software > bug, but then it looks even weirder than that. Alam? I have checked with HW team , the QPIC ECC HW engine reports the bit error byte wise not bit wise. e.g Byte0 --> 2-bitflips --> QPIC ECC counts 1 only Byte1 --> 3-bitflips --> QPIC ECC counts 1 only Byte2 --> 1-bitflips --> QPIC ECC counts 1 only Byte3 --> 4-bitflips --> QPIC ECC counts 1 only (in 8-bit ecc) Byte4 --> 6-bitflips --> QPIC ECC counts 1 only (in 8-bit ecc) Hope this can clearify the things now. Thanks, Alam.
diff --git a/drivers/spi/spi-qpic-snand.c b/drivers/spi/spi-qpic-snand.c index dfc8cc5d97624fe741121228b97d2b3562cc5cc4..5e2eacb83b08016ab85a4b676a06f5dfb8cf5808 100644 --- a/drivers/spi/spi-qpic-snand.c +++ b/drivers/spi/spi-qpic-snand.c @@ -283,9 +283,22 @@ static int qcom_spi_ecc_init_ctx_pipelined(struct nand_device *nand) goto err_free_ecc_cfg; } - if (ecc_cfg->strength != 4) { + switch (ecc_cfg->strength) { + case 4: + ecc_cfg->ecc_mode = ECC_MODE_4BIT; + ecc_cfg->ecc_bytes_hw = 7; + ecc_cfg->spare_bytes = 4; + break; + + case 8: + ecc_cfg->ecc_mode = ECC_MODE_8BIT; + ecc_cfg->ecc_bytes_hw = 13; + ecc_cfg->spare_bytes = 2; + break; + + default: dev_err(snandc->dev, - "only 4 bits ECC strength is supported\n"); + "only 4 or 8 bits ECC strength is supported\n"); ret = -EOPNOTSUPP; goto err_free_ecc_cfg; } @@ -302,8 +315,6 @@ static int qcom_spi_ecc_init_ctx_pipelined(struct nand_device *nand) nand->ecc.ctx.priv = ecc_cfg; snandc->qspi->mtd = mtd; - ecc_cfg->ecc_bytes_hw = 7; - ecc_cfg->spare_bytes = 4; ecc_cfg->bbm_size = 1; ecc_cfg->bch_enabled = true; ecc_cfg->bytes = ecc_cfg->ecc_bytes_hw + ecc_cfg->spare_bytes + ecc_cfg->bbm_size; @@ -349,7 +360,7 @@ static int qcom_spi_ecc_init_ctx_pipelined(struct nand_device *nand) FIELD_PREP(ECC_SW_RESET, 0) | FIELD_PREP(ECC_NUM_DATA_BYTES_MASK, ecc_cfg->cw_data) | FIELD_PREP(ECC_FORCE_CLK_OPEN, 1) | - FIELD_PREP(ECC_MODE_MASK, ECC_MODE_4BIT) | + FIELD_PREP(ECC_MODE_MASK, ecc_cfg->ecc_mode) | FIELD_PREP(ECC_PARITY_SIZE_BYTES_BCH_MASK, ecc_cfg->ecc_bytes_hw); ecc_cfg->ecc_buf_cfg = 0x203 << NUM_STEPS;
Even though the hardware supports 8 bits ECC strength, but that is not handled in the driver yet. This change adds the missing bits in order to allow using the driver with chips which require 8 bits ECC strength. No functional changes intended with regard to the existing 4 bits ECC strength support. Tested on an IPQ9574 platform using a GigaDevice GD5F2GM7REYIG chip. Signed-off-by: Gabor Juhos <j4g8y7@gmail.com> --- mtdtest results: # dmesg | grep nand [ 0.678143] spi-nand spi0.0: GigaDevice SPI NAND was found. [ 0.687393] spi-nand spi0.0: 256 MiB, block size: 128 KiB, page size: 2048, OOB size: 128 # cat /proc/mtd dev: size erasesize name mtd0: 10000000 00020000 "spi0.0" # insmod mtd_test # insmod mtd_speedtest dev=0 [ 63.128425] [ 63.128452] ================================================= [ 63.128979] mtd_speedtest: MTD device: 0 [ 63.134622] mtd_speedtest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 [ 63.139561] mtd_test: scanning for bad eraseblocks [ 63.756447] mtd_test: scanned 2048 eraseblocks, 0 are bad [ 71.085514] mtd_speedtest: testing eraseblock write speed [ 202.745977] mtd_speedtest: eraseblock write speed is 1991 KiB/s [ 202.746022] mtd_speedtest: testing eraseblock read speed [ 284.104591] mtd_speedtest: eraseblock read speed is 3222 KiB/s [ 291.405533] mtd_speedtest: testing page write speed [ 422.516341] mtd_speedtest: page write speed is 1999 KiB/s [ 422.516384] mtd_speedtest: testing page read speed [ 504.144630] mtd_speedtest: page read speed is 3211 KiB/s [ 511.476726] mtd_speedtest: testing 2 page write speed [ 643.114443] mtd_speedtest: 2 page write speed is 1991 KiB/s [ 643.114485] mtd_speedtest: testing 2 page read speed [ 724.434752] mtd_speedtest: 2 page read speed is 3223 KiB/s [ 724.434796] mtd_speedtest: Testing erase speed [ 731.792729] mtd_speedtest: erase speed is 35648 KiB/s [ 731.792772] mtd_speedtest: Testing 2x multi-block erase speed [ 739.162513] mtd_speedtest: 2x multi-block erase speed is 35589 KiB/s [ 739.162558] mtd_speedtest: Testing 4x multi-block erase speed [ 746.486241] mtd_speedtest: 4x multi-block erase speed is 35820 KiB/s [ 746.486287] mtd_speedtest: Testing 8x multi-block erase speed [ 753.789683] mtd_speedtest: 8x multi-block erase speed is 35919 KiB/s [ 753.789728] mtd_speedtest: Testing 16x multi-block erase speed [ 761.093075] mtd_speedtest: 16x multi-block erase speed is 35920 KiB/s [ 761.093120] mtd_speedtest: Testing 32x multi-block erase speed [ 768.396145] mtd_speedtest: 32x multi-block erase speed is 35922 KiB/s [ 768.396222] mtd_speedtest: Testing 64x multi-block erase speed [ 775.699819] mtd_speedtest: 64x multi-block erase speed is 35918 KiB/s [ 775.699863] mtd_speedtest: finished [ 775.705259] ================================================= # insmod mtd_readtest dev=0 [ 919.060671] [ 919.060699] ================================================= [ 919.061226] mtd_readtest: MTD device: 0 [ 919.066957] mtd_readtest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 [ 919.070556] mtd_test: scanning for bad eraseblocks [ 919.086016] mtd_test: scanned 2048 eraseblocks, 0 are bad [ 919.089465] mtd_readtest: testing page read [ 1090.778227] mtd_readtest: finished [ 1090.778286] ================================================= # insmod mtd_pagetest dev=0 [ 1216.297313] [ 1216.297341] ================================================= [ 1216.297867] mtd_pagetest: MTD device: 0 [ 1216.303509] mtd_pagetest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 [ 1216.307213] mtd_test: scanning for bad eraseblocks [ 1216.322680] mtd_test: scanned 2048 eraseblocks, 0 are bad [ 1216.326077] mtd_pagetest: erasing whole device [ 1223.694968] mtd_pagetest: erased 2048 eraseblocks [ 1223.695009] mtd_pagetest: writing whole device [ 1223.763930] mtd_pagetest: written up to eraseblock 0 [ 1240.268942] mtd_pagetest: written up to eraseblock 256 [ 1256.641498] mtd_pagetest: written up to eraseblock 512 [ 1273.139048] mtd_pagetest: written up to eraseblock 768 [ 1289.718929] mtd_pagetest: written up to eraseblock 1024 [ 1306.244553] mtd_pagetest: written up to eraseblock 1280 [ 1322.939723] mtd_pagetest: written up to eraseblock 1536 [ 1339.246937] mtd_pagetest: written up to eraseblock 1792 [ 1355.613729] mtd_pagetest: written 2048 eraseblocks [ 1355.613770] mtd_pagetest: verifying all eraseblocks [ 1355.854290] mtd_pagetest: verified up to eraseblock 0 [ 1416.657733] mtd_pagetest: verified up to eraseblock 256 [ 1477.384593] mtd_pagetest: verified up to eraseblock 512 [ 1538.008142] mtd_pagetest: verified up to eraseblock 768 [ 1599.080797] mtd_pagetest: verified up to eraseblock 1024 [ 1660.775431] mtd_pagetest: verified up to eraseblock 1280 [ 1722.177149] mtd_pagetest: verified up to eraseblock 1536 [ 1783.090166] mtd_pagetest: verified up to eraseblock 1792 [ 1844.450757] mtd_pagetest: verified 2048 eraseblocks [ 1844.450798] mtd_pagetest: crosstest [ 1844.455676] mtd_pagetest: reading page at 0x0 [ 1844.458603] mtd_pagetest: reading page at 0xffff800 [ 1844.463047] mtd_pagetest: reading page at 0x0 [ 1844.467790] mtd_pagetest: verifying pages read at 0x0 match [ 1844.471636] mtd_pagetest: crosstest ok [ 1844.477062] mtd_pagetest: erasecrosstest [ 1844.480833] mtd_pagetest: erasing block 0 [ 1844.488498] mtd_pagetest: writing 1st page of block 0 [ 1844.489821] mtd_pagetest: reading 1st page of block 0 [ 1844.494475] mtd_pagetest: verifying 1st page of block 0 [ 1844.498942] mtd_pagetest: erasing block 0 [ 1844.507505] mtd_pagetest: writing 1st page of block 0 [ 1844.509042] mtd_pagetest: erasing block 2047 [ 1844.516725] mtd_pagetest: reading 1st page of block 0 [ 1844.518087] mtd_pagetest: verifying 1st page of block 0 [ 1844.522415] mtd_pagetest: erasecrosstest ok [ 1844.527495] mtd_pagetest: erasetest [ 1844.531613] mtd_pagetest: erasing block 0 [ 1844.538671] mtd_pagetest: writing 1st page of block 0 [ 1844.540249] mtd_pagetest: erasing block 0 [ 1844.547869] mtd_pagetest: reading 1st page of block 0 [ 1844.548927] mtd_pagetest: verifying 1st page of block 0 is all 0xff [ 1844.553326] mtd_pagetest: erasetest ok [ 1844.559440] mtd_pagetest: finished with 0 errors [ 1844.563233] ================================================= # insmod mtd_subpagetest dev=0 [ 1942.429708] [ 1942.429736] ================================================= [ 1942.430262] mtd_subpagetest: MTD device: 0 [ 1942.435905] mtd_subpagetest: MTD device size 268435456, eraseblock size 131072, page size 2048, subpage size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 [ 1942.439994] mtd_test: scanning for bad eraseblocks [ 1942.457111] mtd_test: scanned 2048 eraseblocks, 0 are bad [ 1949.824564] mtd_subpagetest: writing whole device [ 1949.826670] mtd_subpagetest: written up to eraseblock 0 [ 1950.351816] mtd_subpagetest: written up to eraseblock 256 [ 1950.875797] mtd_subpagetest: written up to eraseblock 512 [ 1951.399912] mtd_subpagetest: written up to eraseblock 768 [ 1951.923618] mtd_subpagetest: written up to eraseblock 1024 [ 1952.447361] mtd_subpagetest: written up to eraseblock 1280 [ 1952.970834] mtd_subpagetest: written up to eraseblock 1536 [ 1953.494635] mtd_subpagetest: written up to eraseblock 1792 [ 1954.016265] mtd_subpagetest: written 2048 eraseblocks [ 1954.016294] mtd_subpagetest: verifying all eraseblocks [ 1954.021617] mtd_subpagetest: verified up to eraseblock 0 [ 1954.347458] mtd_subpagetest: verified up to eraseblock 256 [ 1954.667446] mtd_subpagetest: verified up to eraseblock 512 [ 1954.987343] mtd_subpagetest: verified up to eraseblock 768 [ 1955.307385] mtd_subpagetest: verified up to eraseblock 1024 [ 1955.627462] mtd_subpagetest: verified up to eraseblock 1280 [ 1955.947277] mtd_subpagetest: verified up to eraseblock 1536 [ 1956.266834] mtd_subpagetest: verified up to eraseblock 1792 [ 1956.585581] mtd_subpagetest: verified 2048 eraseblocks [ 1963.889308] mtd_subpagetest: verifying all eraseblocks for 0xff [ 1963.930487] mtd_subpagetest: verified up to eraseblock 0 [ 1974.592567] mtd_subpagetest: verified up to eraseblock 256 [ 1985.180953] mtd_subpagetest: verified up to eraseblock 512 [ 1995.805397] mtd_subpagetest: verified up to eraseblock 768 [ 2006.348859] mtd_subpagetest: verified up to eraseblock 1024 [ 2016.900530] mtd_subpagetest: verified up to eraseblock 1280 [ 2027.447587] mtd_subpagetest: verified up to eraseblock 1536 [ 2037.962383] mtd_subpagetest: verified up to eraseblock 1792 [ 2048.587863] mtd_subpagetest: verified 2048 eraseblocks [ 2048.587906] mtd_subpagetest: writing whole device [ 2048.648174] mtd_subpagetest: written up to eraseblock 0 [ 2062.643145] mtd_subpagetest: written up to eraseblock 256 [ 2076.699015] mtd_subpagetest: written up to eraseblock 512 [ 2091.004910] mtd_subpagetest: written up to eraseblock 768 [ 2105.149879] mtd_subpagetest: written up to eraseblock 1024 [ 2119.470691] mtd_subpagetest: written up to eraseblock 1280 [ 2133.746861] mtd_subpagetest: written up to eraseblock 1536 [ 2147.776477] mtd_subpagetest: written up to eraseblock 1792 [ 2161.947734] mtd_subpagetest: written 2048 eraseblocks [ 2161.947776] mtd_subpagetest: verifying all eraseblocks [ 2161.986109] mtd_subpagetest: verified up to eraseblock 0 [ 2170.818316] mtd_subpagetest: verified up to eraseblock 256 [ 2179.596875] mtd_subpagetest: verified up to eraseblock 512 [ 2188.405116] mtd_subpagetest: verified up to eraseblock 768 [ 2197.188588] mtd_subpagetest: verified up to eraseblock 1024 [ 2206.002204] mtd_subpagetest: verified up to eraseblock 1280 [ 2214.784815] mtd_subpagetest: verified up to eraseblock 1536 [ 2223.557141] mtd_subpagetest: verified up to eraseblock 1792 [ 2232.472832] mtd_subpagetest: verified 2048 eraseblocks [ 2239.818213] mtd_subpagetest: verifying all eraseblocks for 0xff [ 2239.861404] mtd_subpagetest: verified up to eraseblock 0 [ 2250.439035] mtd_subpagetest: verified up to eraseblock 256 [ 2261.176485] mtd_subpagetest: verified up to eraseblock 512 [ 2271.713183] mtd_subpagetest: verified up to eraseblock 768 [ 2282.356892] mtd_subpagetest: verified up to eraseblock 1024 [ 2292.891424] mtd_subpagetest: verified up to eraseblock 1280 [ 2303.543110] mtd_subpagetest: verified up to eraseblock 1536 [ 2314.116690] mtd_subpagetest: verified up to eraseblock 1792 [ 2324.607804] mtd_subpagetest: verified 2048 eraseblocks [ 2324.607846] mtd_subpagetest: finished with 0 errors [ 2324.611859] ================================================= # insmod mtd_oobtest dev=0 [ 2336.159109] [ 2336.159138] ================================================= [ 2336.159664] mtd_oobtest: MTD device: 0 [ 2336.165308] mtd_oobtest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 [ 2336.169043] mtd_test: scanning for bad eraseblocks [ 2336.184354] mtd_test: scanned 2048 eraseblocks, 0 are bad [ 2336.187716] mtd_oobtest: test 1 of 5 [ 2343.495966] mtd_oobtest: writing OOBs of whole device [ 2343.496073] mtd_oobtest: written up to eraseblock 0 [ 2343.516803] mtd_oobtest: written up to eraseblock 256 [ 2343.533527] mtd_oobtest: written up to eraseblock 512 [ 2343.549945] mtd_oobtest: written up to eraseblock 768 [ 2343.563666] mtd_oobtest: written up to eraseblock 1024 [ 2343.575186] mtd_oobtest: written up to eraseblock 1280 [ 2343.584310] mtd_oobtest: written up to eraseblock 1536 [ 2343.593011] mtd_oobtest: written up to eraseblock 1792 [ 2343.600847] mtd_oobtest: written 2048 eraseblocks [ 2343.600861] mtd_oobtest: verifying all eraseblocks [ 2343.604542] mtd_oobtest: verified up to eraseblock 0 [ 2343.616606] mtd_oobtest: verified up to eraseblock 256 [ 2343.623992] mtd_oobtest: verified up to eraseblock 512 [ 2343.631390] mtd_oobtest: verified up to eraseblock 768 [ 2343.638788] mtd_oobtest: verified up to eraseblock 1024 [ 2343.646184] mtd_oobtest: verified up to eraseblock 1280 [ 2343.653570] mtd_oobtest: verified up to eraseblock 1536 [ 2343.660970] mtd_oobtest: verified up to eraseblock 1792 [ 2343.668356] mtd_oobtest: verified 2048 eraseblocks [ 2343.668369] mtd_oobtest: test 2 of 5 [ 2350.985635] mtd_oobtest: writing OOBs of whole device [ 2350.985743] mtd_oobtest: written up to eraseblock 0 [ 2351.006445] mtd_oobtest: written up to eraseblock 256 [ 2351.023170] mtd_oobtest: written up to eraseblock 512 [ 2351.039645] mtd_oobtest: written up to eraseblock 768 [ 2351.053395] mtd_oobtest: written up to eraseblock 1024 [ 2351.064954] mtd_oobtest: written up to eraseblock 1280 [ 2351.074144] mtd_oobtest: written up to eraseblock 1536 [ 2351.082848] mtd_oobtest: written up to eraseblock 1792 [ 2351.090707] mtd_oobtest: written 2048 eraseblocks [ 2351.090721] mtd_oobtest: verifying all eraseblocks [ 2351.094373] mtd_oobtest: verified up to eraseblock 0 [ 2351.099353] mtd_oobtest: verified up to eraseblock 256 [ 2351.104460] mtd_oobtest: verified up to eraseblock 512 [ 2351.109437] mtd_oobtest: verified up to eraseblock 768 [ 2351.114528] mtd_oobtest: verified up to eraseblock 1024 [ 2351.119683] mtd_oobtest: verified up to eraseblock 1280 [ 2351.124772] mtd_oobtest: verified up to eraseblock 1536 [ 2351.129996] mtd_oobtest: verified up to eraseblock 1792 [ 2351.135187] mtd_oobtest: verified 2048 eraseblocks [ 2351.140130] mtd_oobtest: test 3 of 5 [ 2358.448438] mtd_oobtest: writing OOBs of whole device [ 2358.448546] mtd_oobtest: written up to eraseblock 0 [ 2358.469297] mtd_oobtest: written up to eraseblock 256 [ 2358.486095] mtd_oobtest: written up to eraseblock 512 [ 2358.501993] mtd_oobtest: written up to eraseblock 768 [ 2358.515473] mtd_oobtest: written up to eraseblock 1024 [ 2358.526708] mtd_oobtest: written up to eraseblock 1280 [ 2358.535426] mtd_oobtest: written up to eraseblock 1536 [ 2358.544152] mtd_oobtest: written up to eraseblock 1792 [ 2358.551732] mtd_oobtest: written 2048 eraseblocks [ 2358.551744] mtd_oobtest: verifying all eraseblocks [ 2358.555424] mtd_oobtest: verified up to eraseblock 0 [ 2358.567572] mtd_oobtest: verified up to eraseblock 256 [ 2358.575045] mtd_oobtest: verified up to eraseblock 512 [ 2358.582537] mtd_oobtest: verified up to eraseblock 768 [ 2358.590024] mtd_oobtest: verified up to eraseblock 1024 [ 2358.597511] mtd_oobtest: verified up to eraseblock 1280 [ 2358.604984] mtd_oobtest: verified up to eraseblock 1536 [ 2358.612468] mtd_oobtest: verified up to eraseblock 1792 [ 2358.619923] mtd_oobtest: verified 2048 eraseblocks [ 2358.619936] mtd_oobtest: test 4 of 5 [ 2365.924669] mtd_oobtest: attempting to start write past end of OOB [ 2365.924711] mtd_oobtest: an error is expected... [ 2365.929795] mtd_oobtest: error occurred as expected [ 2365.934520] mtd_oobtest: attempting to start read past end of OOB [ 2365.939150] mtd_oobtest: an error is expected... [ 2365.945371] mtd_oobtest: error occurred as expected [ 2365.950087] mtd_oobtest: attempting to write past end of device [ 2365.954660] mtd_oobtest: an error is expected... [ 2365.960623] mtd_oobtest: error occurred as expected [ 2365.965422] mtd_oobtest: attempting to read past end of device [ 2365.970064] mtd_oobtest: an error is expected... [ 2365.975925] mtd_oobtest: error occurred as expected [ 2365.984256] mtd_oobtest: attempting to write past end of device [ 2365.985300] mtd_oobtest: an error is expected... [ 2365.991242] mtd_oobtest: error: wrote past end of device [ 2365.996064] mtd_oobtest: attempting to read past end of device [ 2366.001389] mtd_oobtest: an error is expected... [ 2366.007028] mtd_oobtest: error: read past end of device [ 2366.011776] mtd_oobtest: test 5 of 5 [ 2373.317991] mtd_oobtest: writing OOBs of whole device [ 2373.318034] mtd_oobtest: written up to eraseblock 0 [ 2373.322028] mtd_oobtest: written up to eraseblock 0 [ 2373.327465] mtd_oobtest: written up to eraseblock 256 [ 2373.331576] mtd_oobtest: written up to eraseblock 256 [ 2373.337501] mtd_oobtest: written up to eraseblock 512 [ 2373.341820] mtd_oobtest: written up to eraseblock 512 [ 2373.347566] mtd_oobtest: written up to eraseblock 768 [ 2373.351888] mtd_oobtest: written up to eraseblock 768 [ 2373.357634] mtd_oobtest: written up to eraseblock 1024 [ 2373.361957] mtd_oobtest: written up to eraseblock 1024 [ 2373.367710] mtd_oobtest: written up to eraseblock 1280 [ 2373.372113] mtd_oobtest: written up to eraseblock 1280 [ 2373.377841] mtd_oobtest: written up to eraseblock 1536 [ 2373.382355] mtd_oobtest: written up to eraseblock 1536 [ 2373.387962] mtd_oobtest: written up to eraseblock 1792 [ 2373.392597] mtd_oobtest: written up to eraseblock 1792 [ 2373.398190] mtd_oobtest: written 2047 eraseblocks [ 2373.402838] mtd_oobtest: verifying all eraseblocks [ 2373.407629] mtd_oobtest: verified up to eraseblock 0 [ 2373.412483] mtd_oobtest: verified up to eraseblock 256 [ 2373.417625] mtd_oobtest: verified up to eraseblock 512 [ 2373.422518] mtd_oobtest: verified up to eraseblock 768 [ 2373.427650] mtd_oobtest: verified up to eraseblock 1024 [ 2373.432760] mtd_oobtest: verified up to eraseblock 1280 [ 2373.437912] mtd_oobtest: verified up to eraseblock 1536 [ 2373.443091] mtd_oobtest: verified up to eraseblock 1792 [ 2373.448337] mtd_oobtest: verified 2047 eraseblocks [ 2373.453358] mtd_oobtest: finished with 2 errors [ 2373.458250] ================================================= Note: the two errors are present even even without this patch when testing the driver with a flash chip requiring 4 bits ECC strength. # insmod mtd_stresstest dev=0 [ 2383.256453] [ 2383.256482] ================================================= [ 2383.257008] mtd_stresstest: MTD device: 0 [ 2383.262650] mtd_stresstest: MTD device size 268435456, eraseblock size 131072, page size 2048, count of eraseblocks 2048, pages per eraseblock 64, OOB size 128 [ 2383.268254] mtd_test: scanning for bad eraseblocks [ 2383.281992] mtd_test: scanned 2048 eraseblocks, 0 are bad [ 2383.285565] mtd_stresstest: doing operations [ 2383.291047] mtd_stresstest: 0 operations done [ 2427.841267] mtd_stresstest: 1024 operations done [ 2471.142229] mtd_stresstest: 2048 operations done [ 2514.405277] mtd_stresstest: 3072 operations done [ 2555.451926] mtd_stresstest: 4096 operations done [ 2598.107133] mtd_stresstest: 5120 operations done [ 2639.936952] mtd_stresstest: 6144 operations done [ 2680.724751] mtd_stresstest: 7168 operations done [ 2720.344163] mtd_stresstest: 8192 operations done [ 2761.645640] mtd_stresstest: 9216 operations done [ 2791.760534] mtd_stresstest: finished, 10000 operations done [ 2791.760817] ================================================= # --- drivers/spi/spi-qpic-snand.c | 21 ++++++++++++++++----- 1 file changed, 16 insertions(+), 5 deletions(-)