| Message ID | 20220820195750.70861-13-brad@pensando.io |
|---|---|
| State | New |
| Headers | show |
| Series | Support AMD Pensando Elba SoC | expand |
On 9/11/22 11:20 AM, Serge Semin wrote: > On Wed, Aug 31, 2022 at 06:04:02PM +0000, Larson, Bradley wrote: >> On 8/21/22 11:18 AM, Serge Semin wrote: >>> On Sat, Aug 20, 2022 at 12:57:45PM -0700, Brad Larson wrote: >>>> From: Brad Larson <blarson@amd.com> >>>> >>>> The AMD Pensando Elba SoC includes a DW apb_ssi v4 controller >>>> with device specific chip-select control. The Elba SoC >>>> provides four chip-selects where the native DW IP supports >>>> two chip-selects. The Elba DW_SPI instance has two native >>>> CS signals that are always overridden. >>>> >>>> Signed-off-by: Brad Larson <blarson@amd.com> >>>> --- >>>> drivers/spi/spi-dw-mmio.c | 77 +++++++++++++++++++++++++++++++++++++++ >>>> 1 file changed, 77 insertions(+) >>>> >>>> diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c >>>> index 26c40ea6dd12..36b8c5e10bb3 100644 >>>> --- a/drivers/spi/spi-dw-mmio.c >>>> +++ b/drivers/spi/spi-dw-mmio.c >>>> @@ -53,6 +53,24 @@ struct dw_spi_mscc { >>>> void __iomem *spi_mst; /* Not sparx5 */ >>>> }; >>>> >>>> +struct dw_spi_elba { >>>> + struct regmap *syscon; >>>> +}; >>>> + >>>> +/* >>>> + * Elba SoC does not use ssi, pin override is used for cs 0,1 and >>>> + * gpios for cs 2,3 as defined in the device tree. >>>> + * >>>> + * cs: | 1 0 >>>> + * bit: |---3-------2-------1-------0 >>>> + * | cs1 cs1_ovr cs0 cs0_ovr >>>> + */ >>>> +#define ELBA_SPICS_REG 0x2468 >>>> +#define ELBA_SPICS_SHIFT(cs) (2 * (cs)) >>>> +#define ELBA_SPICS_MASK(cs) (0x3 << ELBA_SPICS_SHIFT(cs)) >>>> +#define ELBA_SPICS_SET(cs, val) \ >>>> + ((((val) << 1) | 0x1) << ELBA_SPICS_SHIFT(cs)) >>> Please take the @Andy' notes into account: >>> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Flkml%2FCAHp75Vex0VkECYd%3DkY0m6%3DjXBYSXg2UFu7vn271%2BQ49WZn22GA%40mail.gmail.com%2F&data=05%7C01%7Cbradley.larson%40amd.com%7C9e7cade823344b72f34608da94224dc6%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637985172338293739%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=usQHWyOxaoD6iasP2R9VL5i0ZkSzBbdpsPljExHemfE%3D&reserved=0 >> Yes, I had a tested change for this but missed adding to the patch update. >> This is the change and I'll resend just this patch. >> >> --- a/drivers/spi/spi-dw-mmio.c >> +++ b/drivers/spi/spi-dw-mmio.c >> @@ -66,10 +66,6 @@ struct dw_spi_elba { >> * | cs1 cs1_ovr cs0 cs0_ovr >> */ >> #define ELBA_SPICS_REG 0x2468 >> -#define ELBA_SPICS_SHIFT(cs) (2 * (cs)) >> -#define ELBA_SPICS_MASK(cs) (0x3 << ELBA_SPICS_SHIFT(cs)) >> -#define ELBA_SPICS_SET(cs, val) \ >> - ((((val) << 1) | 0x1) << ELBA_SPICS_SHIFT(cs)) > Why do you remove these macros? Just replace 0x3 with GENMASM(1, 0), > 0x1 with BIT(0), (2 * (cs)) statement with ((cs) << 1) as Andy > suggested. Using macros for such complex statement is a good practice. > > Also please rename ELBA_SPICS_SHIFT() to ELBA_SPICS_OFFSET() so to > have a more coherent CSR-related macros naming in the driver. Yes, will add back/rename macros with usage of BIT()/GENMASK() and resend just this patch. Regards, Brad
diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c index 26c40ea6dd12..36b8c5e10bb3 100644 --- a/drivers/spi/spi-dw-mmio.c +++ b/drivers/spi/spi-dw-mmio.c @@ -53,6 +53,24 @@ struct dw_spi_mscc { void __iomem *spi_mst; /* Not sparx5 */ }; +struct dw_spi_elba { + struct regmap *syscon; +}; + +/* + * Elba SoC does not use ssi, pin override is used for cs 0,1 and + * gpios for cs 2,3 as defined in the device tree. + * + * cs: | 1 0 + * bit: |---3-------2-------1-------0 + * | cs1 cs1_ovr cs0 cs0_ovr + */ +#define ELBA_SPICS_REG 0x2468 +#define ELBA_SPICS_SHIFT(cs) (2 * (cs)) +#define ELBA_SPICS_MASK(cs) (0x3 << ELBA_SPICS_SHIFT(cs)) +#define ELBA_SPICS_SET(cs, val) \ + ((((val) << 1) | 0x1) << ELBA_SPICS_SHIFT(cs)) + /* * The Designware SPI controller (referred to as master in the documentation) * automatically deasserts chip select when the tx fifo is empty. The chip @@ -237,6 +255,64 @@ static int dw_spi_canaan_k210_init(struct platform_device *pdev, return 0; } +static void dw_spi_elba_override_cs(struct dw_spi_elba *dwselba, int cs, int enable) +{ + regmap_update_bits(dwselba->syscon, ELBA_SPICS_REG, ELBA_SPICS_MASK(cs), + ELBA_SPICS_SET(cs, enable)); +} + +static void dw_spi_elba_set_cs(struct spi_device *spi, bool enable) +{ + struct dw_spi *dws = spi_master_get_devdata(spi->master); + struct dw_spi_mmio *dwsmmio = container_of(dws, struct dw_spi_mmio, dws); + struct dw_spi_elba *dwselba = dwsmmio->priv; + u8 cs; + + cs = spi->chip_select; + if (cs < 2) + dw_spi_elba_override_cs(dwselba, spi->chip_select, enable); + + /* + * The DW SPI controller needs a native CS bit selected to start + * the serial engine. + */ + spi->chip_select = 0; + dw_spi_set_cs(spi, enable); + spi->chip_select = cs; +} + +static int dw_spi_elba_init(struct platform_device *pdev, + struct dw_spi_mmio *dwsmmio) +{ + const char *syscon_name = "amd,pensando-elba-syscon"; + struct device_node *np = pdev->dev.of_node; + struct device_node *node; + struct dw_spi_elba *dwselba; + struct regmap *regmap; + + node = of_parse_phandle(np, syscon_name, 0); + if (!node) { + dev_err(&pdev->dev, "failed to find %s\n", syscon_name); + return -ENODEV; + } + + regmap = syscon_node_to_regmap(node); + if (IS_ERR(regmap)) { + dev_err(&pdev->dev, "syscon regmap lookup failed\n"); + return PTR_ERR(regmap); + } + + dwselba = devm_kzalloc(&pdev->dev, sizeof(*dwselba), GFP_KERNEL); + if (!dwselba) + return -ENOMEM; + + dwselba->syscon = regmap; + dwsmmio->priv = dwselba; + dwsmmio->dws.set_cs = dw_spi_elba_set_cs; + + return 0; +} + static int dw_spi_mmio_probe(struct platform_device *pdev) { int (*init_func)(struct platform_device *pdev, @@ -352,6 +428,7 @@ static const struct of_device_id dw_spi_mmio_of_match[] = { { .compatible = "intel,thunderbay-ssi", .data = dw_spi_intel_init}, { .compatible = "microchip,sparx5-spi", dw_spi_mscc_sparx5_init}, { .compatible = "canaan,k210-spi", dw_spi_canaan_k210_init}, + { .compatible = "amd,pensando-elba-spi", .data = dw_spi_elba_init}, { /* end of table */} }; MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);