[PATCH v4 1/6] mmc: sdhci-esdhc-imx: add imx7d support and support HS400
From: Haibo Chen
Date: Wed Aug 05 2015 - 06:36:10 EST
The imx7d usdhc is derived from imx6sx, the difference is that
imx7d support HS400.
So introduce a new compatible string for imx7d and add HS400
support for imx7d usdhc.
Signed-off-by: Haibo Chen <haibo.chen@xxxxxxxxxxxxx>
---
drivers/mmc/host/sdhci-esdhc-imx.c | 81 ++++++++++++++++++++++++++++++++++++++
1 file changed, 81 insertions(+)
diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-esdhc-imx.c
index c6b9f64..48f009c 100644
--- a/drivers/mmc/host/sdhci-esdhc-imx.c
+++ b/drivers/mmc/host/sdhci-esdhc-imx.c
@@ -44,6 +44,7 @@
#define ESDHC_MIX_CTRL_EXE_TUNE (1 << 22)
#define ESDHC_MIX_CTRL_SMPCLK_SEL (1 << 23)
#define ESDHC_MIX_CTRL_FBCLK_SEL (1 << 25)
+#define ESDHC_MIX_CTRL_HS400_EN (1 << 26)
/* Bits 3 and 6 are not SDHCI standard definitions */
#define ESDHC_MIX_CTRL_SDHCI_MASK 0xb7
/* Tuning bits */
@@ -60,6 +61,16 @@
#define ESDHC_TUNE_CTRL_MIN 0
#define ESDHC_TUNE_CTRL_MAX ((1 << 7) - 1)
+/* strobe dll register */
+#define ESDHC_STROBE_DLL_CTRL 0x70
+#define ESDHC_STROBE_DLL_CTRL_ENABLE (1 << 0)
+#define ESDHC_STROBE_DLL_CTRL_RESET (1 << 1)
+#define ESDHC_STROBE_DLL_CTRL_SLV_DLY_TARGET_SHIFT 3
+
+#define ESDHC_STROBE_DLL_STATUS 0x74
+#define ESDHC_STROBE_DLL_STS_REF_LOCK (1 << 1)
+#define ESDHC_STROBE_DLL_STS_SLV_LOCK 0x1
+
#define ESDHC_TUNING_CTRL 0xcc
#define ESDHC_STD_TUNING_EN (1 << 24)
/* NOTE: the minimum valid tuning start tap for mx6sl is 1 */
@@ -120,6 +131,11 @@
#define ESDHC_FLAG_ERR004536 BIT(7)
/* The IP supports HS200 mode */
#define ESDHC_FLAG_HS200 BIT(8)
+/* The IP supports HS400 mode */
+#define ESDHC_FLAG_HS400 BIT(9)
+
+/* A higher clock ferquency than this rate requires strobell dll control */
+#define ESDHC_STROBE_DLL_CLK_FREQ 100000000
struct esdhc_soc_data {
u32 flags;
@@ -156,6 +172,12 @@ static struct esdhc_soc_data usdhc_imx6sx_data = {
| ESDHC_FLAG_HAVE_CAP1 | ESDHC_FLAG_HS200,
};
+static struct esdhc_soc_data usdhc_imx7d_data = {
+ .flags = ESDHC_FLAG_USDHC | ESDHC_FLAG_STD_TUNING
+ | ESDHC_FLAG_HAVE_CAP1 | ESDHC_FLAG_HS200
+ | ESDHC_FLAG_HS400,
+};
+
struct pltfm_imx_data {
u32 scratchpad;
struct pinctrl *pinctrl;
@@ -199,6 +221,7 @@ static const struct of_device_id imx_esdhc_dt_ids[] = {
{ .compatible = "fsl,imx6sx-usdhc", .data = &usdhc_imx6sx_data, },
{ .compatible = "fsl,imx6sl-usdhc", .data = &usdhc_imx6sl_data, },
{ .compatible = "fsl,imx6q-usdhc", .data = &usdhc_imx6q_data, },
+ { .compatible = "fsl,imx7d-usdhc", .data = &usdhc_imx7d_data, },
{ /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, imx_esdhc_dt_ids);
@@ -274,6 +297,9 @@ static u32 esdhc_readl_le(struct sdhci_host *host, int reg)
val = SDHCI_SUPPORT_DDR50 | SDHCI_SUPPORT_SDR104
| SDHCI_SUPPORT_SDR50
| SDHCI_USE_SDR50_TUNING;
+
+ if (imx_data->socdata->flags & ESDHC_FLAG_HS400)
+ val |= SDHCI_SUPPORT_HS400;
}
}
@@ -774,6 +800,7 @@ static int esdhc_change_pinstate(struct sdhci_host *host,
break;
case MMC_TIMING_UHS_SDR104:
case MMC_TIMING_MMC_HS200:
+ case MMC_TIMING_MMC_HS400:
pinctrl = imx_data->pins_200mhz;
break;
default:
@@ -784,6 +811,44 @@ static int esdhc_change_pinstate(struct sdhci_host *host,
return pinctrl_select_state(imx_data->pinctrl, pinctrl);
}
+/*
+ * For HS400 eMMC, there is a data_strobe line, this signal is generated
+ * by the device and used for data output and CRC status response output
+ * in HS400 mode. The frequency of this signal follows the frequency of
+ * CLK generated by host. Host receive the data which is aligned to the
+ * edge of data_strobe line. Due to the time delay between CLK line and
+ * data_strobe line, if the delay time is larger than one clock cycle,
+ * then CLK and data_strobe line will misaligned, read error shows up.
+ * So when the CLK is higher than 100MHz, each clock cycle is short enough,
+ * host should config the delay target.
+ */
+static void esdhc_set_strobe_dll(struct sdhci_host *host)
+{
+ u32 v;
+
+ if (host->mmc->actual_clock > ESDHC_STROBE_DLL_CLK_FREQ) {
+ /* force a reset on strobe dll */
+ writel(ESDHC_STROBE_DLL_CTRL_RESET,
+ host->ioaddr + ESDHC_STROBE_DLL_CTRL);
+ /*
+ * enable strobe dll ctrl and adjust the delay target
+ * for the uSDHC loopback read clock
+ */
+ v = ESDHC_STROBE_DLL_CTRL_ENABLE |
+ (7 << ESDHC_STROBE_DLL_CTRL_SLV_DLY_TARGET_SHIFT);
+ writel(v, host->ioaddr + ESDHC_STROBE_DLL_CTRL);
+ /* wait 1us to make sure strobe dll status register stable */
+ udelay(1);
+ v = readl(host->ioaddr + ESDHC_STROBE_DLL_STATUS);
+ if (!(v & ESDHC_STROBE_DLL_STS_REF_LOCK))
+ dev_warn(mmc_dev(host->mmc),
+ "warning! HS400 strobe DLL status REF not lock!\n");
+ if (!(v & ESDHC_STROBE_DLL_STS_SLV_LOCK))
+ dev_warn(mmc_dev(host->mmc),
+ "warning! HS400 strobe DLL status SLV not lock!\n");
+ }
+}
+
static void esdhc_set_uhs_signaling(struct sdhci_host *host, unsigned timing)
{
struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
@@ -795,7 +860,13 @@ static void esdhc_set_uhs_signaling(struct sdhci_host *host, unsigned timing)
case MMC_TIMING_UHS_SDR25:
case MMC_TIMING_UHS_SDR50:
case MMC_TIMING_UHS_SDR104:
+ break;
case MMC_TIMING_MMC_HS200:
+ /* disable ddr mode and disable HS400 mode */
+ writel(readl(host->ioaddr + ESDHC_MIX_CTRL) &
+ ~(ESDHC_MIX_CTRL_DDREN | ESDHC_MIX_CTRL_HS400_EN),
+ host->ioaddr + ESDHC_MIX_CTRL);
+ imx_data->is_ddr = 0;
break;
case MMC_TIMING_UHS_DDR50:
case MMC_TIMING_MMC_DDR52:
@@ -813,6 +884,13 @@ static void esdhc_set_uhs_signaling(struct sdhci_host *host, unsigned timing)
writel(v, host->ioaddr + ESDHC_DLL_CTRL);
}
break;
+ case MMC_TIMING_MMC_HS400:
+ writel(readl(host->ioaddr + ESDHC_MIX_CTRL) |
+ ESDHC_MIX_CTRL_DDREN | ESDHC_MIX_CTRL_HS400_EN,
+ host->ioaddr + ESDHC_MIX_CTRL);
+ imx_data->is_ddr = 1;
+ esdhc_set_strobe_dll(host);
+ break;
}
esdhc_change_pinstate(host, timing);
@@ -1100,6 +1178,9 @@ static int sdhci_esdhc_imx_probe(struct platform_device *pdev)
if (imx_data->socdata->flags & ESDHC_FLAG_ERR004536)
host->quirks |= SDHCI_QUIRK_BROKEN_ADMA;
+ if (imx_data->socdata->flags & ESDHC_FLAG_HS400)
+ host->quirks2 |= SDHCI_QUIRK2_CAPS_BIT63_FOR_HS400;
+
if (of_id)
err = sdhci_esdhc_imx_probe_dt(pdev, host, imx_data);
else
--
1.9.1
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