| Message ID | 20230312004445.15913-11-blarson@amd.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Support AMD Pensando Elba SoC | expand |
On Sat, Mar 11, 2023 at 04:44:40PM -0800, Brad Larson 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. > > Signed-off-by: Brad Larson <blarson@amd.com> > --- > > v11 changes: > - Simplify dw_spi_elb_init by using syscon_regmap_lookup_by_phandle() > > v10 changes: > - Delete struct dw_spi_elba, use regmap directly in priv > > v9 changes: > - Add use of macros GENMASK() and BIT() > - Change ELBA_SPICS_SHIFT() to ELBA_SPICS_OFFSET() > > --- > drivers/spi/spi-dw-mmio.c | 57 +++++++++++++++++++++++++++++++++++++++ > 1 file changed, 57 insertions(+) > > diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c > index 26c40ea6dd12..5851ecc6e1e9 100644 > --- 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 +251,48 @@ 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) > +{ > + struct regmap *syscon; > + > + syscon = syscon_regmap_lookup_by_phandle(dev_of_node(&pdev->dev), > + "amd,pensando-elba-syscon"); > + 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; | +-------------------------------------+ | Newline here + would be nice. Other than that looks good. Reviewed-by: Serge Semin <fancer.lancer@gmail.com> -Serge(y) > + > + return 0; > +} > + > static int dw_spi_mmio_probe(struct platform_device *pdev) > { > int (*init_func)(struct platform_device *pdev, > @@ -352,6 +408,7 @@ 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); > -- > 2.17.1 >
diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c index 26c40ea6dd12..5851ecc6e1e9 100644 --- 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 +251,48 @@ 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) +{ + struct regmap *syscon; + + syscon = syscon_regmap_lookup_by_phandle(dev_of_node(&pdev->dev), + "amd,pensando-elba-syscon"); + 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 +408,7 @@ 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> --- v11 changes: - Simplify dw_spi_elb_init by using syscon_regmap_lookup_by_phandle() v10 changes: - Delete struct dw_spi_elba, use regmap directly in priv v9 changes: - Add use of macros GENMASK() and BIT() - Change ELBA_SPICS_SHIFT() to ELBA_SPICS_OFFSET() --- drivers/spi/spi-dw-mmio.c | 57 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 57 insertions(+)