Re: [PATCH V2 2/3] mmc: sdhci-pci-gli: Set SDR104's clock to 205MHz and enable SSC for GL9767

From: Adrian Hunter
Date: Wed May 31 2023 - 03:01:56 EST


On 30/05/23 12:53, Victor Shih wrote:
> From: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>
>
> Set GL9767 SDR104's clock to 205MHz and enable SSC feature
> depend on register 0x888 BIT(1).
>
> Signed-off-by: Ben Chuang <ben.chuang@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Victor Shih <victor.shih@xxxxxxxxxxxxxxxxxxx>
> ---
> drivers/mmc/host/sdhci-pci-gli.c | 135 ++++++++++++++++++++++++++++++-
> 1 file changed, 134 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sdhci-pci-gli.c b/drivers/mmc/host/sdhci-pci-gli.c
> index 3ed207b89d1a..178253a7e86f 100644
> --- a/drivers/mmc/host/sdhci-pci-gli.c
> +++ b/drivers/mmc/host/sdhci-pci-gli.c
> @@ -158,6 +158,12 @@
> #define GLI_9767_VHS_REV_M 0x1
> #define GLI_9767_VHS_REV_W 0x2
>
> +#define PCIE_GLI_9767_COM_MAILBOX 0x888
> +#define PCIE_GLI_9767_COM_MAILBOX_SSC_EN BIT(1)
> +
> +#define PCIE_GLI_9767_CFG 0x8A0
> +#define PCIE_GLI_9767_CFG_LOW_PWR_OFF BIT(12)
> +
> #define PCIE_GLI_9767_PWR_MACRO_CTL 0x8D0
> #define PCIE_GLI_9767_PWR_MACRO_CTL_LOW_VOLTAGE GENMASK(3, 0)
> #define PCIE_GLI_9767_PWR_MACRO_CTL_LD0_LOW_OUTPUT_VOLTAGE GENMASK(15, 12)
> @@ -175,6 +181,16 @@
> #define PCIE_GLI_9767_SCR_CORE_PWR_D3_OFF BIT(21)
> #define PCIE_GLI_9767_SCR_CFG_RST_DATA_LINK_DOWN BIT(30)
>
> +#define PCIE_GLI_9767_SD_PLL_CTL 0x938
> +#define PCIE_GLI_9767_SD_PLL_CTL_PLL_LDIV GENMASK(9, 0)
> +#define PCIE_GLI_9767_SD_PLL_CTL_PLL_PDIV GENMASK(15, 12)
> +#define PCIE_GLI_9767_SD_PLL_CTL_PLL_DIR_EN BIT(16)
> +#define PCIE_GLI_9767_SD_PLL_CTL_SSC_EN BIT(19)
> +#define PCIE_GLI_9767_SD_PLL_CTL_SSC_STEP_SETTING GENMASK(28, 24)
> +
> +#define PCIE_GLI_9767_SD_PLL_CTL2 0x93C
> +#define PCIE_GLI_9767_SD_PLL_CTL2_PLLSSC_PPM GENMASK(31, 16)
> +
> #define GLI_MAX_TUNING_LOOP 40
>
> /* Genesys Logic chipset */
> @@ -753,6 +769,123 @@ static inline void gl9767_vhs_write(struct pci_dev *pdev)
> pci_write_config_dword(pdev, PCIE_GLI_9767_VHS, vhs_value);
> }
>
> +static bool gl9767_ssc_enable(struct pci_dev *pdev)
> +{
> + u32 value;
> + u8 enable;
> +
> + gl9767_vhs_write(pdev);
> +
> + pci_read_config_dword(pdev, PCIE_GLI_9767_COM_MAILBOX, &value);
> + enable = FIELD_GET(PCIE_GLI_9767_COM_MAILBOX_SSC_EN, value);
> +
> + gl9767_vhs_read(pdev);
> +
> + return enable;
> +}
> +
> +static void gl9767_set_ssc(struct pci_dev *pdev, u8 enable, u8 step, u16 ppm)
> +{
> + u32 pll;
> + u32 ssc;
> +
> + gl9767_vhs_write(pdev);
> +
> + pci_read_config_dword(pdev, PCIE_GLI_9767_SD_PLL_CTL, &pll);
> + pci_read_config_dword(pdev, PCIE_GLI_9767_SD_PLL_CTL2, &ssc);
> + pll &= ~(PCIE_GLI_9767_SD_PLL_CTL_SSC_STEP_SETTING |
> + PCIE_GLI_9767_SD_PLL_CTL_SSC_EN);
> + ssc &= ~PCIE_GLI_9767_SD_PLL_CTL2_PLLSSC_PPM;
> + pll |= FIELD_PREP(PCIE_GLI_9767_SD_PLL_CTL_SSC_STEP_SETTING, step) |
> + FIELD_PREP(PCIE_GLI_9767_SD_PLL_CTL_SSC_EN, enable);
> + ssc |= FIELD_PREP(PCIE_GLI_9767_SD_PLL_CTL2_PLLSSC_PPM, ppm);
> + pci_write_config_dword(pdev, PCIE_GLI_9767_SD_PLL_CTL2, ssc);
> + pci_write_config_dword(pdev, PCIE_GLI_9767_SD_PLL_CTL, pll);
> +
> + gl9767_vhs_read(pdev);
> +}
> +
> +static void gl9767_set_pll(struct pci_dev *pdev, u8 dir, u16 ldiv, u8 pdiv)
> +{
> + u32 pll;
> +
> + gl9767_vhs_write(pdev);
> +
> + pci_read_config_dword(pdev, PCIE_GLI_9767_SD_PLL_CTL, &pll);
> + pll &= ~(PCIE_GLI_9767_SD_PLL_CTL_PLL_LDIV |
> + PCIE_GLI_9767_SD_PLL_CTL_PLL_PDIV |
> + PCIE_GLI_9767_SD_PLL_CTL_PLL_DIR_EN);
> + pll |= FIELD_PREP(PCIE_GLI_9767_SD_PLL_CTL_PLL_LDIV, ldiv) |
> + FIELD_PREP(PCIE_GLI_9767_SD_PLL_CTL_PLL_PDIV, pdiv) |
> + FIELD_PREP(PCIE_GLI_9767_SD_PLL_CTL_PLL_DIR_EN, dir);
> + pci_write_config_dword(pdev, PCIE_GLI_9767_SD_PLL_CTL, pll);
> +
> + gl9767_vhs_read(pdev);
> +
> + /* wait for pll stable */
> + mdelay(1);

So long as SDHCI_QUIRK_CLOCK_BEFORE_RESET is not used, it is OK
to sleep here, so msleep() or usleep_range()

> +}
> +
> +static void gl9767_set_ssc_pll_205mhz(struct pci_dev *pdev)
> +{
> + bool enable = gl9767_ssc_enable(pdev);
> +
> + /* set pll to 205MHz and ssc */
> + gl9767_set_ssc(pdev, enable, 0x1F, 0xF5C3);
> + gl9767_set_pll(pdev, 0x1, 0x246, 0x0);
> +}
> +
> +static void gl9767_disable_ssc_pll(struct pci_dev *pdev)
> +{
> + u32 pll;
> +
> + gl9767_vhs_write(pdev);
> +
> + pci_read_config_dword(pdev, PCIE_GLI_9767_SD_PLL_CTL, &pll);
> + pll &= ~(PCIE_GLI_9767_SD_PLL_CTL_PLL_DIR_EN | PCIE_GLI_9767_SD_PLL_CTL_SSC_EN);
> + pci_write_config_dword(pdev, PCIE_GLI_9767_SD_PLL_CTL, pll);
> +
> + gl9767_vhs_read(pdev);
> +}
> +
> +static void sdhci_gl9767_set_clock(struct sdhci_host *host, unsigned int clock)
> +{
> + struct sdhci_pci_slot *slot = sdhci_priv(host);
> + struct mmc_ios *ios = &host->mmc->ios;
> + struct pci_dev *pdev;
> + u32 value;
> + u16 clk;
> +
> + pdev = slot->chip->pdev;
> + host->mmc->actual_clock = 0;
> +
> + gl9767_vhs_write(pdev);
> +
> + pci_read_config_dword(pdev, PCIE_GLI_9767_CFG, &value);
> + value |= PCIE_GLI_9767_CFG_LOW_PWR_OFF;
> + pci_write_config_dword(pdev, PCIE_GLI_9767_CFG, value);
> +
> + gl9767_disable_ssc_pll(pdev);
> + sdhci_writew(host, 0, SDHCI_CLOCK_CONTROL);
> +
> + if (clock == 0)
> + return;
> +
> + clk = sdhci_calc_clk(host, clock, &host->mmc->actual_clock);
> + if (clock == 200000000 && ios->timing == MMC_TIMING_UHS_SDR104) {
> + host->mmc->actual_clock = 205000000;
> + gl9767_set_ssc_pll_205mhz(pdev);
> + }
> +
> + sdhci_enable_clk(host, clk);
> +
> + pci_read_config_dword(pdev, PCIE_GLI_9767_CFG, &value);
> + value &= ~PCIE_GLI_9767_CFG_LOW_PWR_OFF;
> + pci_write_config_dword(pdev, PCIE_GLI_9767_CFG, value);
> +
> + gl9767_vhs_read(pdev);
> +}
> +
> static void gli_set_9767(struct sdhci_host *host)
> {
> u32 value;
> @@ -1293,7 +1426,7 @@ const struct sdhci_pci_fixes sdhci_gl9763e = {
> };
>
> static const struct sdhci_ops sdhci_gl9767_ops = {
> - .set_clock = sdhci_set_clock,
> + .set_clock = sdhci_gl9767_set_clock,
> .enable_dma = sdhci_pci_enable_dma,
> .set_bus_width = sdhci_set_bus_width,
> .reset = sdhci_gl9767_reset,