Re: [PATCH] spi: dw-mmio: add MSCC Jaguar2 support

From: Gregory CLEMENT
Date: Wed Aug 29 2018 - 08:55:45 EST


Hi Alexandre,

On mer., aoÃt 29 2018, Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx> wrote:

> Unfortunately, the Jaguar2 CPU_SYSTEM_CTRL register set has a different
> layout than the Ocelot one. Handle that while keeping most of the code
> common.
>
> Signed-off-by: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>

Reviewed-by: Gregory CLEMENT <gregory.clement@xxxxxxxxxxx>

Gregory

> ---
>
> Hi,
>
> This is really unfortunate and I hope it will not be necessary to do the same
> for every SoC in the line.
>
> I didn't use a regmap_field because it is only accessed once at probe time.
>
> drivers/spi/spi-dw-mmio.c | 28 ++++++++++++++++++++++------
> 1 file changed, 22 insertions(+), 6 deletions(-)
>
> diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c
> index e80f60ed6fdf..351f49976161 100644
> --- a/drivers/spi/spi-dw-mmio.c
> +++ b/drivers/spi/spi-dw-mmio.c
> @@ -34,8 +34,8 @@ struct dw_spi_mmio {
> };
>
> #define MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL 0x24
> -#define OCELOT_IF_SI_OWNER_MASK GENMASK(5, 4)
> #define OCELOT_IF_SI_OWNER_OFFSET 4
> +#define JAGUAR2_IF_SI_OWNER_OFFSET 6
> #define MSCC_IF_SI_OWNER_SISL 0
> #define MSCC_IF_SI_OWNER_SIBM 1
> #define MSCC_IF_SI_OWNER_SIMC 2
> @@ -76,7 +76,8 @@ static void dw_spi_mscc_set_cs(struct spi_device *spi, bool enable)
> }
>
> static int dw_spi_mscc_init(struct platform_device *pdev,
> - struct dw_spi_mmio *dwsmmio)
> + struct dw_spi_mmio *dwsmmio,
> + const char *cpu_syscon, u32 if_si_owner_offset)
> {
> struct dw_spi_mscc *dwsmscc;
> struct resource *res;
> @@ -92,7 +93,7 @@ static int dw_spi_mscc_init(struct platform_device *pdev,
> return PTR_ERR(dwsmscc->spi_mst);
> }
>
> - dwsmscc->syscon = syscon_regmap_lookup_by_compatible("mscc,ocelot-cpu-syscon");
> + dwsmscc->syscon = syscon_regmap_lookup_by_compatible(cpu_syscon);
> if (IS_ERR(dwsmscc->syscon))
> return PTR_ERR(dwsmscc->syscon);
>
> @@ -101,8 +102,8 @@ static int dw_spi_mscc_init(struct platform_device *pdev,
>
> /* Select the owner of the SI interface */
> regmap_update_bits(dwsmscc->syscon, MSCC_CPU_SYSTEM_CTRL_GENERAL_CTRL,
> - OCELOT_IF_SI_OWNER_MASK,
> - MSCC_IF_SI_OWNER_SIMC << OCELOT_IF_SI_OWNER_OFFSET);
> + 0x3 << if_si_owner_offset,
> + MSCC_IF_SI_OWNER_SIMC << if_si_owner_offset);
>
> dwsmmio->dws.set_cs = dw_spi_mscc_set_cs;
> dwsmmio->priv = dwsmscc;
> @@ -110,6 +111,20 @@ static int dw_spi_mscc_init(struct platform_device *pdev,
> return 0;
> }
>
> +static int dw_spi_mscc_ocelot_init(struct platform_device *pdev,
> + struct dw_spi_mmio *dwsmmio)
> +{
> + return dw_spi_mscc_init(pdev, dwsmmio, "mscc,ocelot-cpu-syscon",
> + OCELOT_IF_SI_OWNER_OFFSET);
> +}
> +
> +static int dw_spi_mscc_jaguar2_init(struct platform_device *pdev,
> + struct dw_spi_mmio *dwsmmio)
> +{
> + return dw_spi_mscc_init(pdev, dwsmmio, "mscc,jaguar2-cpu-syscon",
> + JAGUAR2_IF_SI_OWNER_OFFSET);
> +}
> +
> static int dw_spi_mmio_probe(struct platform_device *pdev)
> {
> int (*init_func)(struct platform_device *pdev,
> @@ -212,7 +227,8 @@ static int dw_spi_mmio_remove(struct platform_device *pdev)
>
> static const struct of_device_id dw_spi_mmio_of_match[] = {
> { .compatible = "snps,dw-apb-ssi", },
> - { .compatible = "mscc,ocelot-spi", .data = dw_spi_mscc_init},
> + { .compatible = "mscc,ocelot-spi", .data = dw_spi_mscc_ocelot_init},
> + { .compatible = "mscc,jaguar2-spi", .data = dw_spi_mscc_jaguar2_init},
> { /* end of table */}
> };
> MODULE_DEVICE_TABLE(of, dw_spi_mmio_of_match);
> --
> 2.18.0
>

--
Gregory Clement, Bootlin
Embedded Linux and Kernel engineering
http://bootlin.com