| Message ID | 20230119035136.21603-12-blarson@amd.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Support AMD Pensando Elba SoC | expand |
On Thu, Jan 19, 2023 at 5:52 AM Brad Larson <blarson@amd.com> wrote: > > 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. ... > +struct dw_spi_elba { > + struct regmap *syscon; > +}; Why can't struct regmap be used directly? ... > +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)); > + Redundant blank line. > +} ... > + dev_err(&pdev->dev, "failed to find %s\n", syscon_name); > + return -ENODEV; return dev_err_probe(); ... > + dev_err(&pdev->dev, "syscon regmap lookup failed\n"); > + return PTR_ERR(regmap); Ditto.
On 19/01/2023 9:58 UTC, Andy Shevchenko wrote: >On Thu, Jan 19, 2023 at 5:52 AM Brad Larson <blarson@amd.com> wrote: >> >> 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. > ... > >> +struct dw_spi_elba { >> + struct regmap *syscon; >> +}; > >Why can't struct regmap be used directly? Yes it can, all that is needed is regmap. See result below. ... > >> +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)); > >> + > >Redundant blank line. Removed ... > >> + dev_err(&pdev->dev, "failed to find %s\n", syscon_name); >> + return -ENODEV; > >return dev_err_probe(); Changed in both places. ... > >> + dev_err(&pdev->dev, "syscon regmap lookup failed\n"); >> + return PTR_ERR(regmap); > >Ditto. Smaller diff with the above change and looks like this: --- a/drivers/spi/spi-dw-mmio.c +++ b/drivers/spi/spi-dw-mmio.c @@ -53,6 +53,20 @@ struct dw_spi_mscc { void __iomem *spi_mst; /* Not sparx5 */ }; +/* + * 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_OFFSET(cs) ((cs) << 1) +#define ELBA_SPICS_MASK(cs) (GENMASK(1, 0) << ELBA_SPICS_OFFSET(cs)) +#define ELBA_SPICS_SET(cs, val) \ + ((((val) << 1) | BIT(0)) << ELBA_SPICS_OFFSET(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 +251,56 @@ static int dw_spi_canaan_k210_init(struct platform_device *pdev, return 0; } +static void dw_spi_elba_override_cs(struct regmap *syscon, int cs, int enable) +{ + regmap_update_bits(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 regmap *syscon = dwsmmio->priv; + u8 cs; + + cs = spi->chip_select; + if (cs < 2) + dw_spi_elba_override_cs(syscon, 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 regmap *syscon; + + node = of_parse_phandle(np, syscon_name, 0); + if (!node) + return dev_err_probe(&pdev->dev, -ENODEV, "failed to find %s\n", + syscon_name); + + syscon = syscon_node_to_regmap(node); + if (IS_ERR(syscon)) + return dev_err_probe(&pdev->dev, PTR_ERR(syscon), + "syscon regmap lookup failed\n"); + + dwsmmio->priv = syscon; + 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 +416,7 @@ 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); Regards, Brad
diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c index 26c40ea6dd12..9b6f876227e8 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_OFFSET(cs) ((cs) << 1) +#define ELBA_SPICS_MASK(cs) (GENMASK(1, 0) << ELBA_SPICS_OFFSET(cs)) +#define ELBA_SPICS_SET(cs, val) \ + ((((val) << 1) | BIT(0)) << ELBA_SPICS_OFFSET(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 +255,65 @@ 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 dw_spi_elba *dwselba; + struct device_node *node; + 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 +429,7 @@ 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);
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> --- Changes since v6: - Add use of macros GENMASK() and BIT() - Change ELBA_SPICS_SHIFT() to ELBA_SPICS_OFFSET() --- drivers/spi/spi-dw-mmio.c | 78 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 78 insertions(+)