Re: [PATCH v5 2/3] mfd: lpc_ich: Add support for SPI serial flash host controller

From: Marek Vasut
Date: Fri Nov 25 2016 - 12:38:24 EST


On 11/14/2016 11:24 AM, Mika Westerberg wrote:
> Many Intel CPUs including Haswell, Broadwell and Baytrail have SPI serial
> flash host controller as part of the LPC device. This will populate an MFD
> cell suitable for the SPI host controller driver if we know that the LPC
> device has one.
>
> Signed-off-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx>
> Acked-by: Lee Jones <lee.jones@xxxxxxxxxx>
> ---
> drivers/mfd/lpc_ich.c | 92 +++++++++++++++++++++++++++++++++++++++++++++
> include/linux/mfd/lpc_ich.h | 3 ++
> 2 files changed, 95 insertions(+)
>
> diff --git a/drivers/mfd/lpc_ich.c b/drivers/mfd/lpc_ich.c
> index c8dee47b45d9..985bda575849 100644
> --- a/drivers/mfd/lpc_ich.c
> +++ b/drivers/mfd/lpc_ich.c
> @@ -83,6 +83,15 @@
> #define ACPIBASE_GCS_OFF 0x3410
> #define ACPIBASE_GCS_END 0x3414
>
> +#define SPIBASE_BYT 0x54
> +#define SPIBASE_BYT_SZ 512
> +#define SPIBASE_BYT_EN BIT(1)
> +
> +#define SPIBASE_LPT 0x3800
> +#define SPIBASE_LPT_SZ 512
> +#define BCR 0xdc
> +#define BCR_WPD BIT(0)
> +
> #define GPIOBASE_ICH0 0x58
> #define GPIOCTRL_ICH0 0x5C
> #define GPIOBASE_ICH6 0x48
> @@ -133,6 +142,12 @@ static struct resource gpio_ich_res[] = {
> },
> };
>
> +static struct resource intel_spi_res[] = {
> + {
> + .flags = IORESOURCE_MEM,
> + }
> +};
> +
> static struct mfd_cell lpc_ich_wdt_cell = {
> .name = "iTCO_wdt",
> .num_resources = ARRAY_SIZE(wdt_ich_res),
> @@ -147,6 +162,14 @@ static struct mfd_cell lpc_ich_gpio_cell = {
> .ignore_resource_conflicts = true,
> };
>
> +
> +static struct mfd_cell lpc_ich_spi_cell = {
> + .name = "intel-spi",
> + .num_resources = ARRAY_SIZE(intel_spi_res),
> + .resources = intel_spi_res,
> + .ignore_resource_conflicts = true,
> +};
> +
> /* chipset related info */
> enum lpc_chipsets {
> LPC_ICH = 0, /* ICH */
> @@ -493,10 +516,12 @@ static struct lpc_ich_info lpc_chipset_info[] = {
> [LPC_LPT] = {
> .name = "Lynx Point",
> .iTCO_version = 2,
> + .spi_type = INTEL_SPI_LPT,
> },
> [LPC_LPT_LP] = {
> .name = "Lynx Point_LP",
> .iTCO_version = 2,
> + .spi_type = INTEL_SPI_LPT,
> },
> [LPC_WBG] = {
> .name = "Wellsburg",
> @@ -510,6 +535,7 @@ static struct lpc_ich_info lpc_chipset_info[] = {
> [LPC_BAYTRAIL] = {
> .name = "Bay Trail SoC",
> .iTCO_version = 3,
> + .spi_type = INTEL_SPI_BYT,
> },
> [LPC_COLETO] = {
> .name = "Coleto Creek",
> @@ -518,10 +544,12 @@ static struct lpc_ich_info lpc_chipset_info[] = {
> [LPC_WPT_LP] = {
> .name = "Wildcat Point_LP",
> .iTCO_version = 2,
> + .spi_type = INTEL_SPI_LPT,
> },
> [LPC_BRASWELL] = {
> .name = "Braswell SoC",
> .iTCO_version = 3,
> + .spi_type = INTEL_SPI_BYT,
> },
> [LPC_LEWISBURG] = {
> .name = "Lewisburg",
> @@ -1054,6 +1082,64 @@ static int lpc_ich_init_wdt(struct pci_dev *dev)
> return ret;
> }
>
> +static int lpc_ich_init_spi(struct pci_dev *dev)
> +{
> + struct lpc_ich_priv *priv = pci_get_drvdata(dev);
> + struct resource *res = &intel_spi_res[0];
> + struct intel_spi_boardinfo *info;
> + u32 spi_base, rcba, bcr;
> +
> + info = devm_kzalloc(&dev->dev, sizeof(*info), GFP_KERNEL);
> + if (!info)
> + return -ENOMEM;
> +
> + info->type = lpc_chipset_info[priv->chipset].spi_type;
> +
> + switch (info->type) {
> + case INTEL_SPI_BYT:
> + pci_read_config_dword(dev, SPIBASE_BYT, &spi_base);
> + if (spi_base & SPIBASE_BYT_EN) {
> + res->start = spi_base & ~(SPIBASE_BYT_SZ - 1);
> + res->end = res->start + SPIBASE_BYT_SZ - 1;
> + }
> + break;
> +
> + case INTEL_SPI_LPT:
> + pci_read_config_dword(dev, RCBABASE, &rcba);
> + if (rcba & 1) {
> + spi_base = rcba & ~(SPIBASE_LPT_SZ - 1);

Use the round_down() macro here ?

> + res->start = spi_base + SPIBASE_LPT;
> + res->end = res->start + SPIBASE_LPT_SZ - 1;

[...]


--
Best regards,
Marek Vasut