@@ -7,6 +7,8 @@ Required Properties:
 
 * compatible: should be one of the following
 	- synopsis,dw-mshc: for controllers compliant with synopsis dw-mshc.
+	- synopsis,dw-mshc-exynos5250: for controllers with Samsung
+	  Exynos5250 specific extentions.
 
 * reg: physical base address of the dw-mshc controller and size of its memory
   region.

@@ -55,13 +57,40 @@ Optional properties:
 * no-write-protect: The write protect pad of the controller is not connected
   to the write protect pin on the slot.
 
+Samsung Exynos5250 specific properties:
+
+* samsung,dw-mshc-sdr-timing: Specifies the value of CUI clock divider, CIU
+  clock phase shift value in transmit mode and CIU clock phase shift value in
+  receive mode for single data rate mode operation. Refer notes of the valid
+  values below.
+
+* samsung,dw-mshc-ddr-timing: Specifies the value of CUI clock divider, CIU
+  clock phase shift value in transmit mode and CIU clock phase shift value in
+  receive mode for double data rate mode operation. Refer notes of the valid
+  values below. The order of the cells should be
+
+    - First Cell: 	CIU clock divider value.
+    - Second Cell:	CIU clock phase shift value for tx mode.
+    - Third Cell:	CIU clock phase shift value for rx mode.
+
+  Valid values for SDR and DDR CIU clock timing:
+
+    - valid values for CIU clock divider, tx phase shift and rx phase shift
+      is 0 to 7.
+
+    - When CIU clock divider value is set to 3, all possible 8 phase shift
+      values can be used.
+
+    - If CIU clock divider value is 0 (that is divide by 1), both tx and rx
+      phase shift clocks should be 0.
+
 Example:
 
   The MSHC controller node can be split into two portions, SoC specific and
   board specific portions as listed below.
 
 	dwmmc0 at 12200000 {
-		compatible = "synopsis,dw-mshc";
+		compatible = "synopsis,dw-mshc-exynos5250";
 		reg = <0x12200000 0x1000>;
 		interrupts = <0 75 0>;
 	};

@@ -72,6 +101,8 @@ Example:
 		no-write-protect;
 		fifo-depth = <0x80>;
 		card-detect-delay = <200>;
+		samsung,dw-mshc-sdr-timing = <2 3 3>;
+		samsung,dw-mshc-ddr-timing = <1 2 3>;
 
 		slot0 {
 			bus-width = <8>;

@@ -27,9 +27,17 @@ static struct dw_mci_drv_data synopsis_drv_data = {
 	.ctrl_type	= DW_MCI_TYPE_SYNOPSIS,
 };
 
+static struct dw_mci_drv_data exynos5250_drv_data = {
+	.ctrl_type	= DW_MCI_TYPE_EXYNOS5250,
+	.caps		= MMC_CAP_UHS_DDR50 | MMC_CAP_1_8V_DDR |
+				MMC_CAP_8_BIT_DATA | MMC_CAP_CMD23,
+};
+
 static const struct of_device_id dw_mci_pltfm_match[] = {
 	{ .compatible = "synopsis,dw-mshc",
 			.data = (void *)&synopsis_drv_data, },
+	{ .compatible = "synopsis,dw-mshc-exynos5250",
+			.data = (void *)&exynos5250_drv_data, },
 	{},
 };
 MODULE_DEVICE_TABLE(of, dw_mci_pltfm_match);

@@ -236,6 +236,7 @@ static void dw_mci_set_timeout(struct dw_mci *host)
 static u32 dw_mci_prepare_command(struct mmc_host *mmc, struct mmc_command *cmd)
 {
 	struct mmc_data	*data;
+	struct dw_mci_slot *slot = mmc_priv(mmc);
 	u32 cmdr;
 	cmd->error = -EINPROGRESS;
 

@@ -265,6 +266,10 @@ static u32 dw_mci_prepare_command(struct mmc_host *mmc, struct mmc_command *cmd)
 			cmdr |= SDMMC_CMD_DAT_WR;
 	}
 
+	if (slot->host->drv_data->ctrl_type == DW_MCI_TYPE_EXYNOS5250)
+		if (SDMMC_CLKSEL_GET_SELCLK_DRV(mci_readl(slot->host, CLKSEL)))
+			cmdr |= SDMMC_USE_HOLD_REG;
+
 	return cmdr;
 }
 

@@ -787,10 +792,19 @@ static void dw_mci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	regs = mci_readl(slot->host, UHS_REG);
 
 	/* DDR mode set */
-	if (ios->timing == MMC_TIMING_UHS_DDR50)
+	if (ios->timing == MMC_TIMING_UHS_DDR50) {
 		regs |= (0x1 << slot->id) << 16;
-	else
+		mci_writel(slot->host, CLKSEL, slot->host->ddr_timing);
+	} else {
 		regs &= ~(0x1 << slot->id) << 16;
+		mci_writel(slot->host, CLKSEL, slot->host->sdr_timing);
+	}
+
+	if (slot->host->drv_data->ctrl_type == DW_MCI_TYPE_EXYNOS5250) {
+		slot->host->bus_hz = clk_get_rate(slot->host->ciu_clk);
+		slot->host->bus_hz /= SDMMC_CLKSEL_GET_DIVRATIO(
+					mci_readl(slot->host, CLKSEL));
+	}
 
 	mci_writel(slot->host, UHS_REG, regs);
 

@@ -2074,6 +2088,20 @@ static struct dw_mci_board *dw_mci_parse_dt(struct dw_mci *host)
 		if (of_get_property(np, of_quriks[idx].quirk, NULL))
 			pdata->quirks |= of_quriks[idx].id;
 
+	if (of_property_read_u32_array(dev->of_node,
+			"samsung,dw-mshc-sdr-timing", timing, 3))
+		host->sdr_timing = DW_MCI_DEF_SDR_TIMING;
+	else
+		host->sdr_timing = SDMMC_CLKSEL_TIMING(timing[0],
+					timing[1], timing[2]);
+
+	if (of_property_read_u32_array(dev->of_node,
+			"samsung,dw-mshc-ddr-timing", timing, 3))
+		host->ddr_timing = DW_MCI_DEF_DDR_TIMING;
+	else
+		host->ddr_timing = SDMMC_CLKSEL_TIMING(timing[0],
+					timing[1], timing[2]);
+
 	if (of_property_read_u32(np, "fifo-depth", &pdata->fifo_depth))
 		dev_info(dev, "fifo-depth property not found, using "
 				"value of FIFOTH register as default\n");

@@ -53,6 +53,7 @@
 #define SDMMC_IDINTEN		0x090
 #define SDMMC_DSCADDR		0x094
 #define SDMMC_BUFADDR		0x098
+#define SDMMC_CLKSEL		0x09C /* specific to Samsung Exynos5250 */
 #define SDMMC_DATA(x)		(x)
 
 /*

@@ -111,6 +112,7 @@
 #define SDMMC_INT_ERROR			0xbfc2
 /* Command register defines */
 #define SDMMC_CMD_START			BIT(31)
+#define SDMMC_USE_HOLD_REG		BIT(29)
 #define SDMMC_CMD_CCS_EXP		BIT(23)
 #define SDMMC_CMD_CEATA_RD		BIT(22)
 #define SDMMC_CMD_UPD_CLK		BIT(21)

@@ -142,6 +144,17 @@
 /* Version ID register define */
 #define SDMMC_GET_VERID(x)		((x) & 0xFFFF)
 
+#define DW_MCI_DEF_SDR_TIMING		0x03030002
+#define DW_MCI_DEF_DDR_TIMING		0x03020001
+#define SDMMC_CLKSEL_CCLK_SAMPLE(x)	(((x) & 3) << 0)
+#define SDMMC_CLKSEL_CCLK_DRIVE(x)	(((x) & 3) << 16)
+#define SDMMC_CLKSEL_CCLK_DIVIDER(x)	(((x) & 3) << 24)
+#define SDMMC_CLKSEL_TIMING(x, y, z)	(SDMMC_CLKSEL_CCLK_SAMPLE(x) |	\
+					SDMMC_CLKSEL_CCLK_DRIVE(y) |	\
+					SDMMC_CLKSEL_CCLK_DIVIDER(z))
+#define SDMMC_CLKSEL_GET_DIVRATIO(x)	((((x) >> 24) & 0x7) + 1)
+#define SDMMC_CLKSEL_GET_SELCLK_DRV(x)	(((x) >> 16) & 0x7)
+
 /* Register access macros */
 #define mci_readl(dev, reg)			\
 	__raw_readl((dev)->regs + SDMMC_##reg)

@@ -82,6 +82,8 @@ struct mmc_data;
  * @biu_clk: Pointer to bus interface unit clock instance.
  * @ciu_clk: Pointer to card interface unit clock instance.
  * @slot: Slots sharing this MMC controller.
+ * @sdr_timing: Clock phase shifting for driving and sampling in sdr mode
+ * @ddr_timing: Clock phase shifting for driving and sampling in ddr mode
  * @fifo_depth: depth of FIFO.
  * @data_shift: log2 of FIFO item size.
  * @part_buf_start: Start index in part_buf.

@@ -166,6 +168,10 @@ struct dw_mci {
 	struct clk		*ciu_clk;
 	struct dw_mci_slot	*slot[MAX_MCI_SLOTS];
 
+	/* Phase Shift Value (for exynos5250 variant) */
+	u32			sdr_timing;
+	u32			ddr_timing;
+
 	/* FIFO push and pull */
 	int			fifo_depth;
 	int			data_shift;