| Message ID | 20231219-sam-sparc32-sunset-v3-v1-0-64bb44b598c5@ravnborg.org |
|---|---|
| Headers | show |
| Series | sparc32: sunset sun4m and sun4d | expand |
On 2023-12-20 18:25, John Paul Adrian Glaubitz wrote: > Hi Sam, > > On Wed, 2023-12-20 at 16:22 +0100, Sam Ravnborg wrote: >>> The leon3_generic machine is maintained by different people so I'd suggest >>> contacting them: see [1] for their contact details. I see there is an >>> avocado boot test for the leon3_generic machine included within the QEMU >>> source tree, but it uses a downloadable image of HelenOS rather than Linux. >> >> Thanks for the pointer, I will try to reach out to them when I have >> something a bit more solid than "it does not work". >> >> I tried to hack around a little in qemu and I have an idea where things >> goes wrong. The leon_generic assumes another address layout than what is >> used by the kernel, so the very first jump to a kernel address fails. The MKLINUXIMG second stage bootloader sets up MMU tables and the SPARC OPENPROM interface for LEON systems, so you need to run the vmlinux image through that. You can find it (and our other Linux related releases) via https://gaisler.com/index.php/downloads/linux. The manual is at https://www.gaisler.com/doc/mklinuximg.pdf and the latest release at https://gaisler.com/anonftp/linux/linux-2.6/kernel/mklinuximg-2.0.15.tar.bz2 With a sparc-linux-gcc in the PATH (or using CROSS_COMPILE to point out a toolchain stem) you can do: mklinuximg vmlinux image.ram and then run the resulting image.ram in e.g. QEMU 8.2.0 with qemu-system-sparc -nographic -M leon3_generic -m 256 -kernel image.ram This at least boots the kernel and let me log in when quickly testing a few images with root filesystems in initramfs, admittedly with our kernel patches in place. > I would argue that before we start introducing larger changes to arch/sparc, > we should settle the maintainership question first. Once we have an active > maintainer again, we can have a more extended discussion about what to keep > and how to name things. I agree. Cheers, Andreas
Hi Andreas. Congratulation being the new sparc co-maintainer! On Tue, Dec 19, 2023 at 11:03:05PM +0100, Sam Ravnborg via B4 Relay wrote: > This is the second attempt to sunset sun4m and sun4d. > See [1] for the inital attempt. I have now verified that the kernel can boot with qemu. There was a bug in the uart driver that is fixed and upstream, and then using the instructions you provided I could use buildroot with an external kernel tree to get a booting kernel. Assuming you agree with the patchset how do you want me to move forward? I can rebase on top of the latest -rc and collect acks if that helps. Arnd promised to pick up the patches until you got a git tree up, but I do not expect Arnd to pick up anything unless you have acked or reviewed said patch(es). If I rebase the patch-set I will likely include a few bug-fix patches that was prepared in the meantime. I can also send them as a separate series, no worries. Sam
Hi Andreas, > > diff --git a/arch/sparc/include/asm/winmacro.h b/arch/sparc/include/asm/winmacro.h > > index b6e911f5d93c..c496b04cdfaf 100644 > > --- a/arch/sparc/include/asm/winmacro.h > > +++ b/arch/sparc/include/asm/winmacro.h > > @@ -108,18 +108,11 @@ > > 661: rd %tbr, %idreg; \ > > srl %idreg, 10, %idreg; \ > > and %idreg, 0xc, %idreg; \ > > These three lines, including the label, should also be removed as they > are not for LEON. Additionally, I think it would be best to split out > removing the cpuid instruction fixups to one patch and the MMU ASI > instruction fixups to another patch. Nice catch! I will fix this and split up in two patches in v2. It will take some days before I have v2 ready, and I will base it on top of your for-next branch in the sparc.git tree. Sam > > > - .section .cpuid_patch, "ax"; \ > > - /* Instruction location. */ \ > > - .word 661b; \ > > - /* SUN4D implementation. */ \ > > - lda [%g0] ASI_M_VIKING_TMP1, %idreg; \ > > - sll %idreg, 2, %idreg; \ > > - nop; \ > > - /* LEON implementation. */ \ > > + \ > > rd %asr17, %idreg; \ > > srl %idreg, 0x1c, %idreg; \ > > sll %idreg, 0x02, %idreg; \ > > - .previous; \ > > + \ > > sethi %hi(current_set), %dest_reg; \ > > or %dest_reg, %lo(current_set), %dest_reg;\ > > ld [%idreg + %dest_reg], %dest_reg; > > diff --git a/arch/sparc/kernel/entry.S b/arch/sparc/kernel/entry.S > > index 0f2417ee3f95..9cf8f87e8c42 100644 > > --- a/arch/sparc/kernel/entry.S > > +++ b/arch/sparc/kernel/entry.S > > The hard_smp_processor_id function also needs to be reduced to just the > LEON code. With the patching removed, SMP otherwise breaks with CPUs > other than CPU 0 getting stuck. > > Thanks, > Andreas
This is the second attempt to sunset sun4m and sun4d. See [1] for the inital attempt. The sun4m and sun4d parts of the kernel have seen no real interest for several years now. Last time a few people surfaced, but it was either due to a personal project or for nostalgic reasons. It is time to let go and drop the parts of sparc32 that in reality are not in use. LEON from Frontgrade Gaisler is the only real user of sparc32, and this patchset reduces sparc32 to what is required by LEON. The defconfig is first adapted to the one used by Gaisler. Then the patches removes sun4m and sun4d specific implementations such as small drivers, SMP support, IRQ suppor etc. Removing sun4m and sun4d support allowed removal of the run time patching of the code as well as a lot of assembler code. The result is a much cleaner assembler code that is easier to understand and thus maintain and extend. So far the code builds but it has seen no run-time testing. If anyone can tell me how to boot a linux kernel with the leon_genric machine with QEMU that would be super as this would be a minimal testing that others can reproduce as well. I assume QEMU needs a few patches to make it work, but maybe I just failed to use the right bootloader. TODO before this can be applied: - Ack from davem - as he is the principal sparc maintainer - Tested-by: preferably on a target or QEMU (see above) I expect bugs as there are some involved changes! Ideas for the future - Apply the most relevant downstream Gaisler patches - The ones introducing CAS should have preference as we then can drop the cmpxchg emulation - Adjust defconfig to include all Gaisler drivers to make sure they see build time coverage - Move the leon bits from leon files to the general files - Add leon smp support to smp_32.c - Add leon irq support to irq_32.c - Integrate leom_mm support with srmmu and drop some of the function operations that are no longer needed - The current sparc32 code assume the bootloader uses the prom provided by sun. Maybe migrate over to a more modern device tree way of working. - Drop some of the homegrown memory allocators and use memblocks [1]: https://lore.kernel.org/all/20201218184347.2180772-1-sam@ravnborg.org/ Sam --- Sam Ravnborg (27): sparc32: Update defconfig to LEON SMP sparc32: Drop sun4m/sun4d support from head_32.S sparc32: Drop floppy support sparc32: Drop sun4m specific led driver sparc32: Drop sun specific power management drivers sparc32: Drop auxio support sparc32: Drop run-time patching of ipi trap sparc32: Drop patching of interrupt vector sparc32: Drop sun4m/sun4d specific irq handling sparc32: Drop sun4d/sun4m smp support sparc32: Drop pcic support sparc32: Drop mbus support sparc32: Drop unused function __get_{phys,iospace} sparc32: Drop unused mmu models sparc32: Drop check for sparc_model sparc32: Drop use of sparc_config sparc32: Drop run-time patching of ASI instructions sparc32: Drop support for 7 register windows sparc32: Drop additional sun4d bits sparc32: Drop unused prom ranges support sparc32: Drop unused iommu support sparc32: Drop sun4m irq support sparc32: Drop unused trampoline code sparc32: Drop config SPARC_LEON sparc32: Drop sbus support sbus: char: Drop now unused uctrl driver fbdev/p9100: Drop now unused driver p9100 arch/sparc/Kconfig | 54 +-- arch/sparc/configs/sparc32_defconfig | 170 +++---- arch/sparc/include/asm/asmmacro.h | 22 - arch/sparc/include/asm/auxio_32.h | 73 +-- arch/sparc/include/asm/cpu_type.h | 18 - arch/sparc/include/asm/elf_32.h | 2 - arch/sparc/include/asm/fb.h | 8 +- arch/sparc/include/asm/floppy.h | 2 - arch/sparc/include/asm/floppy_32.h | 393 ---------------- arch/sparc/include/asm/io-unit.h | 59 --- arch/sparc/include/asm/io_32.h | 83 ---- arch/sparc/include/asm/iommu.h | 2 - arch/sparc/include/asm/iommu_32.h | 122 ----- arch/sparc/include/asm/irq_32.h | 2 - arch/sparc/include/asm/mbus.h | 97 ---- arch/sparc/include/asm/mxcc.h | 138 ------ arch/sparc/include/asm/obio.h | 226 --------- arch/sparc/include/asm/oplib_32.h | 11 - arch/sparc/include/asm/pcic.h | 130 ------ arch/sparc/include/asm/pgtable_32.h | 24 - arch/sparc/include/asm/pgtsrmmu.h | 33 +- arch/sparc/include/asm/ross.h | 192 -------- arch/sparc/include/asm/sbi.h | 116 ----- arch/sparc/include/asm/sections.h | 3 - arch/sparc/include/asm/swift.h | 107 ----- arch/sparc/include/asm/switch_to_32.h | 1 - arch/sparc/include/asm/timer_32.h | 1 + arch/sparc/include/asm/tsunami.h | 65 --- arch/sparc/include/asm/turbosparc.h | 126 ----- arch/sparc/include/asm/viking.h | 255 ----------- arch/sparc/include/asm/winmacro.h | 11 +- arch/sparc/kernel/Makefile | 8 +- arch/sparc/kernel/apc.c | 196 -------- arch/sparc/kernel/auxio_32.c | 139 ------ arch/sparc/kernel/cpu.c | 1 - arch/sparc/kernel/devices.c | 10 +- arch/sparc/kernel/entry.S | 413 +---------------- arch/sparc/kernel/etrap_32.S | 50 +- arch/sparc/kernel/head_32.S | 255 +---------- arch/sparc/kernel/ioport.c | 55 +-- arch/sparc/kernel/irq.h | 85 +--- arch/sparc/kernel/irq_32.c | 133 +----- arch/sparc/kernel/kernel.h | 53 +-- arch/sparc/kernel/led.c | 146 ------ arch/sparc/kernel/leon_kernel.c | 53 +-- arch/sparc/kernel/leon_pmc.c | 16 +- arch/sparc/kernel/leon_smp.c | 3 - arch/sparc/kernel/of_device_32.c | 18 +- arch/sparc/kernel/pcic.c | 840 ---------------------------------- arch/sparc/kernel/pmc.c | 100 ---- arch/sparc/kernel/process_32.c | 10 - arch/sparc/kernel/rtrap_32.S | 73 ++- arch/sparc/kernel/setup_32.c | 115 ----- arch/sparc/kernel/smp_32.c | 102 +---- arch/sparc/kernel/sun4d_irq.c | 519 --------------------- arch/sparc/kernel/sun4d_smp.c | 415 ----------------- arch/sparc/kernel/sun4m_irq.c | 478 ------------------- arch/sparc/kernel/sun4m_smp.c | 275 ----------- arch/sparc/kernel/time_32.c | 68 +-- arch/sparc/kernel/trampoline_32.S | 127 +---- arch/sparc/kernel/ttable_32.S | 9 +- arch/sparc/kernel/vmlinux.lds.S | 5 - arch/sparc/kernel/wof.S | 61 +-- arch/sparc/kernel/wuf.S | 41 +- arch/sparc/mm/Makefile | 4 +- arch/sparc/mm/hypersparc.S | 414 ----------------- arch/sparc/mm/io-unit.c | 286 ------------ arch/sparc/mm/iommu.c | 455 ------------------ arch/sparc/mm/mm_32.h | 4 - arch/sparc/mm/srmmu.c | 836 +-------------------------------- arch/sparc/mm/srmmu_access.S | 83 ---- arch/sparc/mm/swift.S | 256 ----------- arch/sparc/mm/tsunami.S | 132 ------ arch/sparc/mm/viking.S | 284 ------------ arch/sparc/prom/Makefile | 1 - arch/sparc/prom/init_32.c | 2 - arch/sparc/prom/misc_32.c | 2 - arch/sparc/prom/ranges.c | 114 ----- drivers/sbus/char/Kconfig | 8 - drivers/sbus/char/Makefile | 1 - drivers/sbus/char/uctrl.c | 435 ------------------ drivers/usb/host/Kconfig | 2 +- drivers/usb/host/ehci-hcd.c | 4 +- drivers/usb/host/uhci-hcd.c | 2 +- drivers/video/fbdev/Kconfig | 10 +- drivers/video/fbdev/Makefile | 1 - drivers/video/fbdev/p9100.c | 372 --------------- sound/sparc/Kconfig | 1 + 88 files changed, 318 insertions(+), 10809 deletions(-) --- base-commit: bee0e7762ad2c6025b9f5245c040fcc36ef2bde8 change-id: 20231219-sam-sparc32-sunset-v3-4751ea89da2d Best regards,