[PATCH v2 3/7] mmc: sdhci-of-dwcmshc: Add support for T-Head TH1520

Drew Fustini
2023-10-17T20:45:28Z

Add support for the mmc controller in the T-Head TH1520 with the new
compatible "thead,th1520-dwcmshc". Implement custom sdhci_ops for
set_uhs_signaling, reset, voltage_switch, and platform_execute_tuning.

Signed-off-by: Drew Fustini <dfustini@baylibre.com>
---
drivers/mmc/host/sdhci-of-dwcmshc.c | 358 ++++++++++++++++++++++++++++++++++++
1 file changed, 358 insertions(+)

diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
index 3a3bae6948a8..88ed0937c4e9 100644
--- a/drivers/mmc/host/sdhci-of-dwcmshc.c
+++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
@@ -8,6 +8,7 @@
*/

#include <linux/acpi.h>
+#include <linux/bitfield.h>
#include <linux/clk.h>
#include <linux/dma-mapping.h>
#include <linux/iopoll.h>
@@ -35,6 +36,21 @@
#define DWCMSHC_CARD_IS_EMMC BIT(0)
#define DWCMSHC_ENHANCED_STROBE BIT(8)
#define DWCMSHC_EMMC_ATCTRL 0x40
+/* Tuning and auto-tuning fields in AT_CTRL_R control register */
+#define AT_CTRL_AT_EN BIT(0) /* autotuning is enabled */
+#define AT_CTRL_CI_SEL BIT(1) /* interval to drive center phase select */
+#define AT_CTRL_SWIN_TH_EN BIT(2) /* sampling window threshold enable */
+#define AT_CTRL_RPT_TUNE_ERR BIT(3) /* enable reporting framing errors */
+#define AT_CTRL_SW_TUNE_EN BIT(4) /* enable software managed tuning */
+#define AT_CTRL_WIN_EDGE_SEL_MASK GENMASK(11, 8) /* bits [11:8] */
+#define AT_CTRL_WIN_EDGE_SEL 0xf /* sampling window edge select */
+#define AT_CTRL_TUNE_CLK_STOP_EN BIT(16) /* clocks stopped during phase code change */
+#define AT_CTRL_PRE_CHANGE_DLY_MASK GENMASK(18, 17) /* bits [18:17] */
+#define AT_CTRL_PRE_CHANGE_DLY 0x1 /* 2-cycle latency */
+#define AT_CTRL_POST_CHANGE_DLY_MASK GENMASK(20, 19) /* bits [20:19] */
+#define AT_CTRL_POST_CHANGE_DLY 0x3 /* 4-cycle latency */
+#define AT_CTRL_SWIN_TH_VAL_MASK GENMASK(31, 24) /* bits [31:24] */
+#define AT_CTRL_SWIN_TH_VAL 0x9 /* sampling window threshold */

/* Rockchip specific Registers */
#define DWCMSHC_EMMC_DLL_CTRL 0x800
@@ -72,6 +88,82 @@
(((x) & DWCMSHC_EMMC_DLL_TIMEOUT) == 0))
#define RK35xx_MAX_CLKS 3

+/* PHY register area pointer */
+#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 */
+
+/* PHY command/response pad settings */
+#define PHY_CMDPAD_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x04)
+
+/* PHY data pad settings */
+#define PHY_DATAPAD_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x06)
+
+/* PHY clock pad settings */
+#define PHY_CLKPAD_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x08)
+
+/* PHY strobe pad settings */
+#define PHY_STBPAD_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x0a)
+
+/* PHY reset pad settings */
+#define PHY_RSTNPAD_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x0c)
+
+/* Bitfields are common for all pad settings */
+#define PHY_PAD_RXSEL_1V8 0x1 /* Receiver type select for 1.8V */
+#define PHY_PAD_RXSEL_3V3 0x2 /* Receiver type select for 3.3V */
+
+#define PHY_PAD_WEAKPULL_MASK GENMASK(4, 3) /* bits [4:3] */
+#define PHY_PAD_WEAKPULL_PULLUP 0x1 /* Weak pull down enabled */
+#define PHY_PAD_WEAKPULL_PULLDOWN 0x2 /* Weak pull down enabled */
+
+#define PHY_PAD_TXSLEW_CTRL_P_MASK GENMASK(8, 5) /* bits [8:5] */
+#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 */
+
+/* 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 */
+
+/* PHY CLK delay line delay code */
+#define PHY_SDCLKDL_DC_R (DWC_MSHC_PTR_PHY_R + 0x1e)
+#define PHY_SDCLKDL_DC_INITIAL 0x40 /* initial delay code */
+#define PHY_SDCLKDL_DC_DEFAULT 0x32 /* default delay code */
+#define PHY_SDCLKDL_DC_HS400 0x18 /* delay code for HS400 mode */
+
+/* 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 */
+
+/* PHY DLL control settings */
+#define PHY_DLL_CTRL_R (DWC_MSHC_PTR_PHY_R + 0x24)
+#define PHY_DLL_CTRL_DISABLE 0x0 /* PHY DLL is enabled */
+#define PHY_DLL_CTRL_ENABLE 0x1 /* PHY DLL is disabled */
+
+/* PHY DLL configuration register 1 */
+#define PHY_DLL_CNFG1_R (DWC_MSHC_PTR_PHY_R + 0x25)
+#define PHY_DLL_CNFG1_SLVDLY_MASK GENMASK(5, 4) /* bits [5:4] */
+#define PHY_DLL_CNFG1_SLVDLY 0x2 /* DLL slave update delay input */
+#define PHY_DLL_CNFG1_WAITCYCLE 0x5 /* DLL wait cycle input */
+
+/* PHY DLL configuration register 2 */
+#define PHY_DLL_CNFG2_R (DWC_MSHC_PTR_PHY_R + 0x26)
+#define PHY_DLL_CNFG2_JUMPSTEP 0xa /* DLL jump step input */
+
+/* PHY DLL master and slave delay line configuration settings */
+#define PHY_DLLDL_CNFG_R (DWC_MSHC_PTR_PHY_R + 0x28)
+#define PHY_DLLDL_CNFG_SLV_INPSEL_MASK GENMASK(6, 5) /* bits [6:5] */
+#define PHY_DLLDL_CNFG_SLV_INPSEL 0x3 /* clock source select for slave DL */
+
+#define FLAG_IO_FIXED_1V8 BIT(0)
+
#define BOUNDARY_OK(addr, len) \
((addr | (SZ_128M - 1)) == ((addr + len - 1) | (SZ_128M - 1)))

@@ -92,6 +184,8 @@ struct dwcmshc_priv {
struct clk *bus_clk;
int vendor_specific_area1; /* P_VENDOR_SPECIFIC_AREA reg */
void *priv; /* pointer to SoC private stuff */
+ u16 delay_line;
+ u16 flags;
};

/*
@@ -157,6 +251,129 @@ static void dwcmshc_request(struct mmc_host *mmc, struct mmc_request *mrq)
sdhci_request(mmc, mrq);
}

+static void th1520_phy_1_8v_init(struct sdhci_host *host)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
+ u32 val;
+
+ if (!priv)
+ return;
+
+ /* deassert phy reset & set tx drive strength */
+ val = PHY_CNFG_RSTN_DEASSERT;
+ val |= FIELD_PREP(PHY_CNFG_PAD_SP_MASK, PHY_CNFG_PAD_SP);
+ val |= FIELD_PREP(PHY_CNFG_PAD_SN_MASK, PHY_CNFG_PAD_SN);
+ sdhci_writel(host, val, PHY_CNFG_R);
+
+ /* disable delay line */
+ sdhci_writeb(host, PHY_SDCLKDL_CNFG_UPDATE, PHY_SDCLKDL_CNFG_R);
+
+ /* set delay line */
+ sdhci_writeb(host, priv->delay_line, PHY_SDCLKDL_DC_R);
+ sdhci_writeb(host, PHY_DLL_CNFG2_JUMPSTEP, PHY_DLL_CNFG2_R);
+
+ /* enable delay lane */
+ val = sdhci_readb(host, PHY_SDCLKDL_CNFG_R);
+ val &= ~(PHY_SDCLKDL_CNFG_UPDATE);
+ sdhci_writeb(host, val, PHY_SDCLKDL_CNFG_R);
+
+ /* configure phy pads */
+ val = PHY_PAD_RXSEL_1V8;
+ 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);
+ 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 = 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);
+ sdhci_writew(host, val, PHY_CLKPAD_CNFG_R);
+
+ val = PHY_PAD_RXSEL_1V8;
+ 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);
+ sdhci_writew(host, val, PHY_STBPAD_CNFG_R);
+
+ /* enable data strobe mode */
+ sdhci_writeb(host, FIELD_PREP(PHY_DLLDL_CNFG_SLV_INPSEL_MASK, PHY_DLLDL_CNFG_SLV_INPSEL),
+ PHY_DLLDL_CNFG_R);
+
+ /* enable phy dll */
+ sdhci_writeb(host, PHY_DLL_CTRL_ENABLE, PHY_DLL_CTRL_R);
+}
+
+static void th1520_phy_3_3v_init(struct sdhci_host *host)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
+ u32 val;
+
+ /* deassert phy reset & set tx drive strength */
+ val = PHY_CNFG_RSTN_DEASSERT;
+ val |= FIELD_PREP(PHY_CNFG_PAD_SP_MASK, PHY_CNFG_PAD_SP);
+ val |= FIELD_PREP(PHY_CNFG_PAD_SN_MASK, PHY_CNFG_PAD_SN);
+ sdhci_writel(host, val, PHY_CNFG_R);
+
+ /* disable delay line */
+ sdhci_writeb(host, PHY_SDCLKDL_CNFG_UPDATE, PHY_SDCLKDL_CNFG_R);
+
+ /* set delay line */
+ sdhci_writeb(host, priv->delay_line, PHY_SDCLKDL_DC_R);
+ sdhci_writeb(host, PHY_DLL_CNFG2_JUMPSTEP, PHY_DLL_CNFG2_R);
+
+ /* enable delay lane */
+ val = sdhci_readb(host, PHY_SDCLKDL_CNFG_R);
+ val &= ~(PHY_SDCLKDL_CNFG_UPDATE);
+ sdhci_writeb(host, val, PHY_SDCLKDL_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);
+ 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 = 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);
+ 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);
+ sdhci_writew(host, val, PHY_STBPAD_CNFG_R);
+
+ /* enable phy dll */
+ sdhci_writeb(host, PHY_DLL_CTRL_ENABLE, PHY_DLL_CTRL_R);
+}
+
+static void th1520_sdhci_set_phy(struct sdhci_host *host)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
+ u16 emmc_ctrl;
+
+ /* Before power on, set PHY configs */
+ if (priv->flags & FLAG_IO_FIXED_1V8)
+ th1520_phy_1_8v_init(host);
+ else
+ th1520_phy_3_3v_init(host);
+
+ if (host->mmc->caps & MMC_CAP_NONREMOVABLE) {
+ emmc_ctrl = sdhci_readw(host, priv->vendor_specific_area1 + DWCMSHC_EMMC_CONTROL);
+ emmc_ctrl |= DWCMSHC_CARD_IS_EMMC;
+ sdhci_writew(host, emmc_ctrl, priv->vendor_specific_area1 + DWCMSHC_EMMC_CONTROL);
+ }
+
+ sdhci_writeb(host, FIELD_PREP(PHY_DLL_CNFG1_SLVDLY_MASK, PHY_DLL_CNFG1_SLVDLY) |
+ PHY_DLL_CNFG1_WAITCYCLE, PHY_DLL_CNFG1_R);
+}
+
static void dwcmshc_set_uhs_signaling(struct sdhci_host *host,
unsigned int timing)
{
@@ -189,9 +406,26 @@ static void dwcmshc_set_uhs_signaling(struct sdhci_host *host,
ctrl_2 |= DWCMSHC_CTRL_HS400;
}

+ if (priv->flags & FLAG_IO_FIXED_1V8)
+ ctrl_2 |= SDHCI_CTRL_VDD_180;
sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
}

+static void th1520_set_uhs_signaling(struct sdhci_host *host,
+ unsigned int timing)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
+
+ dwcmshc_set_uhs_signaling(host, timing);
+ if (timing == MMC_TIMING_MMC_HS400) {
+ priv->delay_line = PHY_SDCLKDL_DC_HS400;
+ th1520_sdhci_set_phy(host);
+ } else {
+ sdhci_writeb(host, 0, PHY_DLLDL_CNFG_R);
+ }
+}
+
static void dwcmshc_hs400_enhanced_strobe(struct mmc_host *mmc,
struct mmc_ios *ios)
{
@@ -338,6 +572,85 @@ static void rk35xx_sdhci_reset(struct sdhci_host *host, u8 mask)
sdhci_reset(host, mask);
}

+static int th1520_execute_tuning(struct sdhci_host *host, u32 opcode)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
+ u32 val = 0;
+
+ if (host->flags & SDHCI_HS400_TUNING)
+ return 0;
+
+ sdhci_writeb(host, FIELD_PREP(PHY_ATDL_CNFG_INPSEL_MASK, PHY_ATDL_CNFG_INPSEL),
+ PHY_ATDL_CNFG_R);
+ val = sdhci_readl(host, priv->vendor_specific_area1 + DWCMSHC_EMMC_ATCTRL);
+
+ /*
+ * configure tuning settings:
+ * - center phase select code driven in block gap interval
+ * - disable reporting of framing errors
+ * - disable software managed tuning
+ * - disable user selection of sampling window edges,
+ * instead tuning calculated edges are used
+ */
+ val &= ~(AT_CTRL_CI_SEL | AT_CTRL_RPT_TUNE_ERR | AT_CTRL_SW_TUNE_EN |
+ FIELD_PREP(AT_CTRL_WIN_EDGE_SEL_MASK, AT_CTRL_WIN_EDGE_SEL));
+
+ /*
+ * configure tuning settings:
+ * - enable auto-tuning
+ * - enable sampling window threshold
+ * - stop clocks during phase code change
+ * - set max latency in cycles between tx and rx clocks
+ * - set max latency in cycles to switch output phase
+ * - set max sampling window threshold value
+ */
+ val |= AT_CTRL_AT_EN | AT_CTRL_SWIN_TH_EN | AT_CTRL_TUNE_CLK_STOP_EN;
+ val |= FIELD_PREP(AT_CTRL_PRE_CHANGE_DLY_MASK, AT_CTRL_PRE_CHANGE_DLY);
+ val |= FIELD_PREP(AT_CTRL_POST_CHANGE_DLY_MASK, AT_CTRL_POST_CHANGE_DLY);
+ val |= FIELD_PREP(AT_CTRL_SWIN_TH_VAL_MASK, AT_CTRL_SWIN_TH_VAL);
+
+ sdhci_writel(host, val, priv->vendor_specific_area1 + DWCMSHC_EMMC_ATCTRL);
+ val = sdhci_readl(host, priv->vendor_specific_area1 + DWCMSHC_EMMC_ATCTRL);
+
+ /* check if is possible to enable auto-tuning */
+ if (!(val & AT_CTRL_AT_EN)) {
+ dev_err(mmc_dev(host->mmc), "failed to enable auto tuning\n");
+ return -EIO;
+ }
+
+ /* perform tuning */
+ sdhci_start_tuning(host);
+ host->tuning_err = __sdhci_execute_tuning(host, opcode);
+ if (host->tuning_err) {
+ /* disable auto-tuning upon tuning error */
+ val &= ~AT_CTRL_AT_EN;
+ sdhci_writel(host, val, priv->vendor_specific_area1 + DWCMSHC_EMMC_ATCTRL);
+ dev_err(mmc_dev(host->mmc), "tuning failed: %d\n", host->tuning_err);
+ return -EIO;
+ }
+ sdhci_end_tuning(host);
+
+ return 0;
+}
+
+static void th1520_sdhci_reset(struct sdhci_host *host, u8 mask)
+{
+ struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+ struct dwcmshc_priv *priv = sdhci_pltfm_priv(pltfm_host);
+ u16 ctrl_2;
+
+ sdhci_reset(host, mask);
+
+ if (priv->flags & FLAG_IO_FIXED_1V8) {
+ ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
+ if (!(ctrl_2 & SDHCI_CTRL_VDD_180)) {
+ ctrl_2 |= SDHCI_CTRL_VDD_180;
+ sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
+ }
+ }
+}
+
static const struct sdhci_ops sdhci_dwcmshc_ops = {
.set_clock = sdhci_set_clock,
.set_bus_width = sdhci_set_bus_width,
@@ -356,6 +669,17 @@ static const struct sdhci_ops sdhci_dwcmshc_rk35xx_ops = {
.adma_write_desc = dwcmshc_adma_write_desc,
};

+static const struct sdhci_ops sdhci_dwcmshc_th1520_ops = {
+ .set_clock = sdhci_set_clock,
+ .set_bus_width = sdhci_set_bus_width,
+ .set_uhs_signaling = th1520_set_uhs_signaling,
+ .get_max_clock = dwcmshc_get_max_clock,
+ .reset = th1520_sdhci_reset,
+ .adma_write_desc = dwcmshc_adma_write_desc,
+ .voltage_switch = th1520_phy_1_8v_init,
+ .platform_execute_tuning = &th1520_execute_tuning,
+};
+
static const struct sdhci_pltfm_data sdhci_dwcmshc_pdata = {
.ops = &sdhci_dwcmshc_ops,
.quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
@@ -379,6 +703,12 @@ static const struct sdhci_pltfm_data sdhci_dwcmshc_rk35xx_pdata = {
SDHCI_QUIRK2_CLOCK_DIV_ZERO_BROKEN,
};

+static const struct sdhci_pltfm_data sdhci_dwcmshc_th1520_pdata = {
+ .ops = &sdhci_dwcmshc_th1520_ops,
+ .quirks = SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
+ .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN,
+};
+
static int dwcmshc_rk35xx_init(struct sdhci_host *host, struct dwcmshc_priv *dwc_priv)
{
int err;
@@ -447,6 +777,10 @@ static const struct of_device_id sdhci_dwcmshc_dt_ids[] = {
.compatible = "snps,dwcmshc-sdhci",
.data = &sdhci_dwcmshc_pdata,
},
+ {
+ .compatible = "thead,th1520-dwcmshc",
+ .data = &sdhci_dwcmshc_th1520_pdata,
+ },
{},
};
MODULE_DEVICE_TABLE(of, sdhci_dwcmshc_dt_ids);
@@ -542,6 +876,30 @@ static int dwcmshc_probe(struct platform_device *pdev)
goto err_clk;
}

+ if (pltfm_data == &sdhci_dwcmshc_th1520_pdata) {
+ priv->delay_line = PHY_SDCLKDL_DC_DEFAULT;
+
+ if ((device_property_read_bool(dev, "mmc-ddr-1_8v")) |
+ (device_property_read_bool(dev, "mmc-hs200-1_8v")) |
+ (device_property_read_bool(dev, "mmc-hs400-1_8v")))
+ priv->flags |= FLAG_IO_FIXED_1V8;
+ else
+ priv->flags &= ~FLAG_IO_FIXED_1V8;
+
+ /*
+ * start_signal_voltage_switch() will try 3.3V first
+ * then 1.8V. Use SDHCI_SIGNALING_180 ranther than
+ * SDHCI_SIGNALING_330 to avoid setting voltage to 3.3V
+ * in sdhci_start_signal_voltage_switch().
+ */
+ if (priv->flags & FLAG_IO_FIXED_1V8) {
+ host->flags &= ~SDHCI_SIGNALING_330;
+ host->flags |= SDHCI_SIGNALING_180;
+ }
+
+ sdhci_enable_v4_mode(host);
+ }
+
#ifdef CONFIG_ACPI
if (pltfm_data == &sdhci_dwcmshc_bf3_pdata)
sdhci_enable_v4_mode(host);

--
2.34.1