Re: [PATCH v5 7/8] mmc: sdhci-of-dwcmshc: Add support for Sophgo SG2042

Adrian Hunter
2024-07-19T13:27:35Z

On 19/07/24 11:47, Chen Wang wrote:
> From: Chen Wang <unicorn_wang@outlook.com>
>
> Add support for the mmc controller of Sophgo SG2042.
>
> SG2042 uses Synopsys PHY the same as TH1520 so we reuse the tuning
> logic from TH1520. Besides this, this patch implement some SG2042
> specific work, such as clocks and reset ops.
>
> Signed-off-by: Chen Wang <unicorn_wang@outlook.com>
> ---
> drivers/mmc/host/sdhci-of-dwcmshc.c | 130 ++++++++++++++++++++++++++--
> 1 file changed, 123 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
> index 972d03ec60e3..d963b8986182 100644
> --- a/drivers/mmc/host/sdhci-of-dwcmshc.c
> +++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
> @@ -113,12 +113,15 @@
> #define DWC_MSHC_PTR_PHY_R 0x300
>
> /* PHY general configuration */
> -#define PHY_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x00)
> -#define PHY_CNFG_RSTN_DEASSERT 0x1 /* Deassert PHY reset */
> -#define PHY_CNFG_PAD_SP_MASK GENMASK(19, 16) /* bits [19:16] */
> -#define PHY_CNFG_PAD_SP 0x0c /* PMOS TX drive strength */
> -#define PHY_CNFG_PAD_SN_MASK GENMASK(23, 20) /* bits [23:20] */
> -#define PHY_CNFG_PAD_SN 0x0c /* NMOS TX drive strength */
> +#define PHY_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x00)
> +#define PHY_CNFG_RSTN_DEASSERT 0x1 /* Deassert PHY reset */
> +#define PHY_CNFG_PHY_PWRGOOD_MASK BIT_MASK(1) /* bit [1] */
> +#define PHY_CNFG_PAD_SP_MASK GENMASK(19, 16) /* bits [19:16] */
> +#define PHY_CNFG_PAD_SP 0x0c /* PMOS TX drive strength */
> +#define PHY_CNFG_PAD_SP_SG2042 0x09 /* PMOS TX drive strength for SG2042 */
> +#define PHY_CNFG_PAD_SN_MASK GENMASK(23, 20) /* bits [23:20] */
> +#define PHY_CNFG_PAD_SN 0x0c /* NMOS TX drive strength */
> +#define PHY_CNFG_PAD_SN_SG2042 0x08 /* NMOS TX drive strength for SG2042 */
>
> /* PHY command/response pad settings */
> #define PHY_CMDPAD_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x04)
> @@ -147,10 +150,12 @@
> #define PHY_PAD_TXSLEW_CTRL_P 0x3 /* Slew control for P-Type pad TX */
> #define PHY_PAD_TXSLEW_CTRL_N_MASK GENMASK(12, 9) /* bits [12:9] */
> #define PHY_PAD_TXSLEW_CTRL_N 0x3 /* Slew control for N-Type pad TX */
> +#define PHY_PAD_TXSLEW_CTRL_N_SG2042 0x2 /* Slew control for N-Type pad TX for SG2042 */
>
> /* PHY CLK delay line settings */
> #define PHY_SDCLKDL_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x1d)
> -#define PHY_SDCLKDL_CNFG_UPDATE BIT(4) /* set before writing to SDCLKDL_DC */
> +#define PHY_SDCLKDL_CNFG_EXTDLY_EN BIT(0)
> +#define PHY_SDCLKDL_CNFG_UPDATE BIT(4) /* set before writing to SDCLKDL_DC */
>
> /* PHY CLK delay line delay code */
> #define PHY_SDCLKDL_DC_R (DWC_MSHC_PTR_PHY_R + 0x1e)
> @@ -158,10 +163,14 @@
> #define PHY_SDCLKDL_DC_DEFAULT 0x32 /* default delay code */
> #define PHY_SDCLKDL_DC_HS400 0x18 /* delay code for HS400 mode */
>
> +#define PHY_SMPLDL_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x20)
> +#define PHY_SMPLDL_CNFG_BYPASS_EN BIT(1)
> +
> /* PHY drift_cclk_rx delay line configuration setting */
> #define PHY_ATDL_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x21)
> #define PHY_ATDL_CNFG_INPSEL_MASK GENMASK(3, 2) /* bits [3:2] */
> #define PHY_ATDL_CNFG_INPSEL 0x3 /* delay line input source */
> +#define PHY_ATDL_CNFG_INPSEL_SG2042 0x2 /* delay line input source for SG2042 */
>
> /* PHY DLL control settings */
> #define PHY_DLL_CTRL_R (DWC_MSHC_PTR_PHY_R + 0x24)
> @@ -1015,6 +1024,90 @@ static int cv18xx_sdhci_execute_tuning(struct sdhci_host *host, u32 opcode)
> return ret;
> }
>
> +static inline void sg2042_sdhci_phy_init(struct sdhci_host *host)
> +{
> + u32 val;
> +
> + /* Asset phy reset & set tx drive strength */
> + val = sdhci_readl(host, PHY_CNFG_R);
> + val &= ~PHY_CNFG_RSTN_DEASSERT;
> + val |= FIELD_PREP(PHY_CNFG_PHY_PWRGOOD_MASK, 1);
> + val |= FIELD_PREP(PHY_CNFG_PAD_SP_MASK, PHY_CNFG_PAD_SP_SG2042);
> + val |= FIELD_PREP(PHY_CNFG_PAD_SN_MASK, PHY_CNFG_PAD_SN_SG2042);
> + sdhci_writel(host, val, PHY_CNFG_R);
> +
> + /* Configure phy pads */
> + val = PHY_PAD_RXSEL_3V3;
> + val |= FIELD_PREP(PHY_PAD_WEAKPULL_MASK, PHY_PAD_WEAKPULL_PULLUP);
> + val |= FIELD_PREP(PHY_PAD_TXSLEW_CTRL_P_MASK, PHY_PAD_TXSLEW_CTRL_P);
> + val |= FIELD_PREP(PHY_PAD_TXSLEW_CTRL_N_MASK, PHY_PAD_TXSLEW_CTRL_N_SG2042);
> + sdhci_writew(host, val, PHY_CMDPAD_CNFG_R);
> + sdhci_writew(host, val, PHY_DATAPAD_CNFG_R);
> + sdhci_writew(host, val, PHY_RSTNPAD_CNFG_R);
> +
> + val = PHY_PAD_RXSEL_3V3;
> + val |= FIELD_PREP(PHY_PAD_TXSLEW_CTRL_P_MASK, PHY_PAD_TXSLEW_CTRL_P);
> + val |= FIELD_PREP(PHY_PAD_TXSLEW_CTRL_N_MASK, PHY_PAD_TXSLEW_CTRL_N_SG2042);
> + sdhci_writew(host, val, PHY_CLKPAD_CNFG_R);
> +
> + val = PHY_PAD_RXSEL_3V3;
> + val |= FIELD_PREP(PHY_PAD_WEAKPULL_MASK, PHY_PAD_WEAKPULL_PULLDOWN);
> + val |= FIELD_PREP(PHY_PAD_TXSLEW_CTRL_P_MASK, PHY_PAD_TXSLEW_CTRL_P);
> + val |= FIELD_PREP(PHY_PAD_TXSLEW_CTRL_N_MASK, PHY_PAD_TXSLEW_CTRL_N_SG2042);
> + sdhci_writew(host, val, PHY_STBPAD_CNFG_R);
> +
> + /* Configure delay line */
> + /* Enable fixed delay */
> + sdhci_writeb(host, PHY_SDCLKDL_CNFG_EXTDLY_EN, PHY_SDCLKDL_CNFG_R);
> + /*
> + * Set delay line.
> + * Its recommended that bit UPDATE_DC[4] is 1 when SDCLKDL_DC is being written.
> + * Ensure UPDATE_DC[4] is '0' when not updating code.
> + */
> + val = sdhci_readb(host, PHY_SDCLKDL_CNFG_R);
> + val |= PHY_SDCLKDL_CNFG_UPDATE;
> + sdhci_writeb(host, val, PHY_SDCLKDL_CNFG_R);
> + /* Add 10 * 70ps = 0.7ns for output delay */
> + sdhci_writeb(host, 10, PHY_SDCLKDL_DC_R);
> + val = sdhci_readb(host, PHY_SDCLKDL_CNFG_R);
> + val &= ~(PHY_SDCLKDL_CNFG_UPDATE);
> + sdhci_writeb(host, val, PHY_SDCLKDL_CNFG_R);
> +
> + /* Set SMPLDL_CNFG, Bypass */
> + sdhci_writeb(host, PHY_SMPLDL_CNFG_BYPASS_EN, PHY_SMPLDL_CNFG_R);
> +
> + /* Set ATDL_CNFG, tuning clk not use for init */
> + val = FIELD_PREP(PHY_ATDL_CNFG_INPSEL_MASK, PHY_ATDL_CNFG_INPSEL_SG2042);
> + sdhci_writeb(host, val, PHY_ATDL_CNFG_R);
> +
> + /* Deasset phy reset */
> + val = sdhci_readl(host, PHY_CNFG_R);
> + val |= PHY_CNFG_RSTN_DEASSERT;
> + sdhci_writel(host, val, PHY_CNFG_R);
> +}
> +
> +static void sg2042_sdhci_reset(struct sdhci_host *host, u8 mask)
> +{
> + sdhci_reset(host, mask);
> +
> + if (mask & SDHCI_RESET_ALL)
> + sg2042_sdhci_phy_init(host);
> +}
> +
> +static int sg2042_init(struct device *dev, struct sdhci_host *host,
> + struct dwcmshc_priv *dwc_priv)
> +{
> + static const char * const clk_ids[] = {"timer"};
> + int err;
> +
> + err = dwcmshc_get_enable_other_clks(mmc_dev(host->mmc), dwc_priv,
> + ARRAY_SIZE(clk_ids), clk_ids);

Can be just:

return dwcmshc_get_enable_other_clks(mmc_dev(host->mmc), dwc_priv,
ARRAY_SIZE(clk_ids), clk_ids);

> + if (err)
> + return err;
> +
> + return 0;
> +}
> +
> static const struct sdhci_ops sdhci_dwcmshc_ops = {
> .set_clock = sdhci_set_clock,
> .set_bus_width = sdhci_set_bus_width,
> @@ -1056,6 +1149,16 @@ static const struct sdhci_ops sdhci_dwcmshc_cv18xx_ops = {
> .platform_execute_tuning = cv18xx_sdhci_execute_tuning,
> };
>
> +static const struct sdhci_ops sdhci_dwcmshc_sg2042_ops = {
> + .set_clock = sdhci_set_clock,
> + .set_bus_width = sdhci_set_bus_width,
> + .set_uhs_signaling = dwcmshc_set_uhs_signaling,
> + .get_max_clock = dwcmshc_get_max_clock,
> + .reset = sg2042_sdhci_reset,
> + .adma_write_desc = dwcmshc_adma_write_desc,
> + .platform_execute_tuning = th1520_execute_tuning,
> +};
> +
> static const struct dwcmshc_pltfm_data sdhci_dwcmshc_pdata = {
> .pdata = {
> .ops = &sdhci_dwcmshc_ops,
> @@ -1104,6 +1207,15 @@ static const struct dwcmshc_pltfm_data sdhci_dwcmshc_cv18xx_pdata = {
> },
> };
>
> +static const struct dwcmshc_pltfm_data sdhci_dwcmshc_sg2042_pdata = {
> + .pdata = {
> + .ops = &sdhci_dwcmshc_sg2042_ops,
> + .quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
> + .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
> + },
> + .init = sg2042_init,
> +};
> +
> static const struct cqhci_host_ops dwcmshc_cqhci_ops = {
> .enable = dwcmshc_sdhci_cqe_enable,
> .disable = sdhci_cqe_disable,
> @@ -1196,6 +1308,10 @@ static const struct of_device_id sdhci_dwcmshc_dt_ids[] = {
> .compatible = "thead,th1520-dwcmshc",
> .data = &sdhci_dwcmshc_th1520_pdata,
> },
> + {
> + .compatible = "sophgo,sg2042-dwcmshc",
> + .data = &sdhci_dwcmshc_sg2042_pdata,
> + },
> {},
> };
> MODULE_DEVICE_TABLE(of, sdhci_dwcmshc_dt_ids);