[PATCH v2 0/11] Changes to support 150 MHz eMMC on rk3399

@@ -35,11 +35,13 @@
 /**
  * struct sdhci_arasan_data
  * @clk_ahb:	Pointer to the AHB clock
- * @phy: Pointer to the generic phy
+ * @phy:	Pointer to the generic phy
+ * @phy_on:	True if the PHY is turned on.
  */
 struct sdhci_arasan_data {
 	struct clk	*clk_ahb;
 	struct phy	*phy;
+	bool		phy_on;
 };
 
 static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host)

@@ -61,12 +63,10 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock)
 {
 	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 	struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
-	bool ctrl_phy = false;
 
-	if (clock > MMC_HIGH_52_MAX_DTR && (!IS_ERR(sdhci_arasan->phy)))
-		ctrl_phy = true;
+	if (sdhci_arasan->phy_on && !IS_ERR(sdhci_arasan->phy)) {
+		sdhci_arasan->phy_on = false;
 
-	if (ctrl_phy) {
 		spin_unlock_irq(&host->lock);
 		phy_power_off(sdhci_arasan->phy);
 		spin_lock_irq(&host->lock);

@@ -74,7 +74,9 @@ static void sdhci_arasan_set_clock(struct sdhci_host *host, unsigned int clock)
 
 	sdhci_set_clock(host, clock);
 
-	if (ctrl_phy) {
+	if (host->mmc->actual_clock && !IS_ERR(sdhci_arasan->phy)) {
+		sdhci_arasan->phy_on = true;
+
 		spin_unlock_irq(&host->lock);
 		phy_power_on(sdhci_arasan->phy);
 		spin_lock_irq(&host->lock);

@@ -257,12 +259,6 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 			goto clk_disable_all;
 		}
 
-		ret = phy_power_on(sdhci_arasan->phy);
-		if (ret < 0) {
-			dev_err(&pdev->dev, "phy_power_on err.\n");
-			goto err_phy_power;
-		}
-
 		host->mmc_host_ops.hs400_enhanced_strobe =
 					sdhci_arasan_hs400_enhanced_strobe;
 	}

@@ -275,9 +271,6 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 
 err_add_host:
 	if (!IS_ERR(sdhci_arasan->phy))
-		phy_power_off(sdhci_arasan->phy);
-err_phy_power:
-	if (!IS_ERR(sdhci_arasan->phy))
 		phy_exit(sdhci_arasan->phy);
 clk_disable_all:
 	clk_disable_unprepare(clk_xin);

@@ -19,9 +19,11 @@
  * your option) any later version.
  */
 
+#include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of_device.h>
 #include <linux/phy/phy.h>
+#include <linux/regmap.h>
 #include "sdhci-pltfm.h"
 
 #define SDHCI_ARASAN_CLK_CTRL_OFFSET	0x2c

@@ -32,18 +34,115 @@
 #define CLK_CTRL_TIMEOUT_MASK		(0xf << CLK_CTRL_TIMEOUT_SHIFT)
 #define CLK_CTRL_TIMEOUT_MIN_EXP	13
 
+/*
+ * On some SoCs the syscon area has a feature where the upper 16-bits of
+ * each 32-bit register act as a write mask for the lower 16-bits.  This allows
+ * atomic updates of the register without locking.  This macro is used on SoCs
+ * that have that feature.
+ */
+#define HIWORD_UPDATE(val, mask, shift) \
+		((val) << (shift) | (mask) << ((shift) + 16))
+
+/**
+ * struct sdhci_arasan_soc_ctl_field - Field used in sdhci_arasan_soc_ctl_map
+ *
+ * @reg:	Offset within the syscon of the register containing this field
+ * @width:	Number of bits for this field
+ * @shift:	Bit offset within @reg of this field (or -1 if not avail)
+ */
+struct sdhci_arasan_soc_ctl_field {
+	u32 reg;
+	u16 width;
+	s16 shift;
+};
+
+/**
+ * struct sdhci_arasan_soc_ctl_map - Map in syscon to corecfg registers
+ *
+ * It's up to the licensee of the Arsan IP block to make these available
+ * somewhere if needed.  Presumably these will be scattered somewhere that's
+ * accessible via the syscon API.
+ *
+ * @baseclkfreq:	Where to find corecfg_baseclkfreq
+ * @hiword_update:	If true, use HIWORD_UPDATE to access the syscon
+ */
+struct sdhci_arasan_soc_ctl_map {
+	struct sdhci_arasan_soc_ctl_field	baseclkfreq;
+	bool					hiword_update;
+};
+
 /**
  * struct sdhci_arasan_data
- * @clk_ahb:	Pointer to the AHB clock
- * @phy:	Pointer to the generic phy
- * @phy_on:	True if the PHY is turned on.
+ * @clk_ahb:		Pointer to the AHB clock
+ * @phy:		Pointer to the generic phy
+ * @phy_on:		True if the PHY is turned on.
+ * @soc_ctl_base:	Pointer to regmap for syscon for soc_ctl registers.
+ * @soc_ctl_map:	Map to get offsets into soc_ctl registers.
  */
 struct sdhci_arasan_data {
 	struct clk	*clk_ahb;
 	struct phy	*phy;
 	bool		phy_on;
+
+	struct regmap	*soc_ctl_base;
+	const struct sdhci_arasan_soc_ctl_map *soc_ctl_map;
+};
+
+static const struct sdhci_arasan_soc_ctl_map rk3399_soc_ctl_map = {
+	.baseclkfreq = { .reg = 0xf000, .width = 8, .shift = 8 },
+	.hiword_update = true,
 };
 
+/**
+ * sdhci_arasan_syscon_write - Write to a field in soc_ctl registers
+ *
+ * This function allows writing to fields in sdhci_arasan_soc_ctl_map.
+ * Note that if a field is specified as not available (shift < 0) then
+ * this function will silently return an error code.  It will be noisy
+ * and print errors for any other (unexpected) errors.
+ *
+ * @host:	The sdhci_host
+ * @fld:	The field to write to
+ * @val:	The value to write
+ */
+static int sdhci_arasan_syscon_write(struct sdhci_host *host,
+				   const struct sdhci_arasan_soc_ctl_field *fld,
+				   u32 val)
+{
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+	struct regmap *soc_ctl_base = sdhci_arasan->soc_ctl_base;
+	u32 reg = fld->reg;
+	u16 width = fld->width;
+	s16 shift = fld->shift;
+	int ret;
+
+	/*
+	 * Silently return errors for shift < 0 so caller doesn't have
+	 * to check for fields which are optional.  For fields that
+	 * are required then caller needs to do something special
+	 * anyway.
+	 */
+	if (shift < 0)
+		return -EINVAL;
+
+	if (sdhci_arasan->soc_ctl_map->hiword_update)
+		ret = regmap_write(soc_ctl_base, reg,
+				   HIWORD_UPDATE(val, GENMASK(width, 0),
+						 shift));
+	else
+		ret = regmap_update_bits(soc_ctl_base, reg,
+					 GENMASK(shift + width, shift),
+					 val << shift);
+
+	/* Yell about (unexpected) regmap errors */
+	if (ret)
+		pr_warn("%s: Regmap write fail: %d\n",
+			 mmc_hostname(host->mmc), ret);
+
+	return ret;
+}
+
 static unsigned int sdhci_arasan_get_timeout_clock(struct sdhci_host *host)
 {
 	u32 div;

@@ -191,9 +290,66 @@ static int sdhci_arasan_resume(struct device *dev)
 static SIMPLE_DEV_PM_OPS(sdhci_arasan_dev_pm_ops, sdhci_arasan_suspend,
 			 sdhci_arasan_resume);
 
+static const struct of_device_id sdhci_arasan_of_match[] = {
+	/* SoC-specific compatible strings w/ soc_ctl_map */
+	{
+		.compatible = "rockchip,rk3399-sdhci-5.1",
+		.data = &rk3399_soc_ctl_map,
+	},
+
+	/* Generic compatible below here */
+	{ .compatible = "arasan,sdhci-8.9a" },
+	{ .compatible = "arasan,sdhci-5.1" },
+	{ .compatible = "arasan,sdhci-4.9a" },
+
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
+
+/**
+ * sdhci_arasan_update_baseclkfreq - Set corecfg_baseclkfreq
+ *
+ * The corecfg_baseclkfreq is supposed to contain the MHz of clk_xin.  This
+ * function can be used to make that happen.
+ *
+ * NOTES:
+ * - Many existing devices don't seem to do this and work fine.  To keep
+ *   compatibility for old hardware where the device tree doesn't provide a
+ *   register map, this function is a noop if a soc_ctl_map hasn't been provided
+ *   for this platform.
+ * - It's assumed that clk_xin is not dynamic and that we use the SDHCI divider
+ *   to achieve lower clock rates.  That means that this function is called once
+ *   at probe time and never called again.
+ *
+ * @host:		The sdhci_host
+ */
+static void sdhci_arasan_update_baseclkfreq(struct sdhci_host *host)
+{
+	struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
+	struct sdhci_arasan_data *sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+	const struct sdhci_arasan_soc_ctl_map *soc_ctl_map =
+		sdhci_arasan->soc_ctl_map;
+	u32 mhz = DIV_ROUND_CLOSEST(clk_get_rate(pltfm_host->clk), 1000000);
+
+	/* Having a map is optional */
+	if (!soc_ctl_map)
+		return;
+
+	/* If we have a map, we expect to have a syscon */
+	if (!sdhci_arasan->soc_ctl_base) {
+		pr_warn("%s: Have regmap, but no soc-ctl-syscon\n",
+			mmc_hostname(host->mmc));
+		return;
+	}
+
+	sdhci_arasan_syscon_write(host, &soc_ctl_map->baseclkfreq, mhz);
+}
+
 static int sdhci_arasan_probe(struct platform_device *pdev)
 {
 	int ret;
+	const struct of_device_id *match;
+	struct device_node *node;
 	struct clk *clk_xin;
 	struct sdhci_host *host;
 	struct sdhci_pltfm_host *pltfm_host;

@@ -207,6 +363,23 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 	pltfm_host = sdhci_priv(host);
 	sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
 
+	match = of_match_node(sdhci_arasan_of_match, pdev->dev.of_node);
+	sdhci_arasan->soc_ctl_map = match->data;
+
+	node = of_parse_phandle(pdev->dev.of_node, "arasan,soc-ctl-syscon", 0);
+	if (node) {
+		sdhci_arasan->soc_ctl_base = syscon_node_to_regmap(node);
+		of_node_put(node);
+
+		if (IS_ERR(sdhci_arasan->soc_ctl_base)) {
+			ret = PTR_ERR(sdhci_arasan->soc_ctl_base);
+			if (ret != -EPROBE_DEFER)
+				dev_err(&pdev->dev, "Can't get syscon: %d\n",
+					ret);
+			goto err_pltfm_free;
+		}
+	}
+
 	sdhci_arasan->clk_ahb = devm_clk_get(&pdev->dev, "clk_ahb");
 	if (IS_ERR(sdhci_arasan->clk_ahb)) {
 		dev_err(&pdev->dev, "clk_ahb clock not found.\n");

@@ -236,6 +409,8 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 	sdhci_get_of_property(pdev);
 	pltfm_host->clk = clk_xin;
 
+	sdhci_arasan_update_baseclkfreq(host);
+
 	ret = mmc_of_parse(host->mmc);
 	if (ret) {
 		dev_err(&pdev->dev, "parsing dt failed (%u)\n", ret);

@@ -301,14 +476,6 @@ static int sdhci_arasan_remove(struct platform_device *pdev)
 	return ret;
 }
 
-static const struct of_device_id sdhci_arasan_of_match[] = {
-	{ .compatible = "arasan,sdhci-8.9a" },
-	{ .compatible = "arasan,sdhci-5.1" },
-	{ .compatible = "arasan,sdhci-4.9a" },
-	{ }
-};
-MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
-
 static struct platform_driver sdhci_arasan_driver = {
 	.driver = {
 		.name = "sdhci-arasan",

@@ -169,20 +169,14 @@ static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
 static int rockchip_emmc_phy_power_off(struct phy *phy)
 {
 	struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
-	int ret = 0;
 
 	/* Power down emmc phy analog blocks */
-	ret = rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_OFF);
-	if (ret)
-		return ret;
-
-	return 0;
+	return rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_OFF);
 }
 
 static int rockchip_emmc_phy_power_on(struct phy *phy)
 {
 	struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
-	int ret = 0;
 
 	/* DLL operation: 200 MHz */
 	regmap_write(rk_phy->reg_base,

@@ -213,11 +207,7 @@ static int rockchip_emmc_phy_power_on(struct phy *phy)
 				   PHYCTRL_OTAPDLYSEL_SHIFT));
 
 	/* Power up emmc phy analog blocks */
-	ret = rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_ON);
-	if (ret)
-		return ret;
-
-	return 0;
+	return rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_ON);
 }
 
 static const struct phy_ops ops = {

@@ -7,6 +7,13 @@ Required properties:
  - reg: PHY register address offset and length in "general
    register files"
 
+Optional clocks using the clock bindings (see ../clock/clock-bindings.txt),
+specified by name:
+ - clock-names: Should contain "emmcclk".  Although this is listed as optional
+		(because most boards can get basic functionality without having
+		access to it), it is strongly suggested.
+ - clocks: Should have a phandle to the card clock exported by the SDHCI driver.
+
 Example:
 
 

@@ -20,6 +27,8 @@ grf: syscon at ff770000 {
 	emmcphy: phy at f780 {
 		compatible = "rockchip,rk3399-emmc-phy";
 		reg = <0xf780 0x20>;
+		clocks = <&sdhci>;
+		clock-names = "emmcclk";
 		#phy-cells = <0>;
 	};
 };

@@ -19,6 +19,7 @@
  * your option) any later version.
  */
 
+#include <linux/clk-provider.h>
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>
 #include <linux/of_device.h>

@@ -73,17 +74,24 @@ struct sdhci_arasan_soc_ctl_map {
 
 /**
  * struct sdhci_arasan_data
+ * @host:		Pointer to the main SDHCI host structure.
  * @clk_ahb:		Pointer to the AHB clock
  * @phy:		Pointer to the generic phy
  * @phy_on:		True if the PHY is turned on.
+ * @sdcardclk_hw:	Struct for the clock we might provide to a PHY.
+ * @sdcardclk:		Pointer to normal 'struct clock' for sdcardclk_hw.
  * @soc_ctl_base:	Pointer to regmap for syscon for soc_ctl registers.
  * @soc_ctl_map:	Map to get offsets into soc_ctl registers.
  */
 struct sdhci_arasan_data {
+	struct sdhci_host *host;
 	struct clk	*clk_ahb;
 	struct phy	*phy;
 	bool		phy_on;
 
+	struct clk_hw	sdcardclk_hw;
+	struct clk      *sdcardclk;
+
 	struct regmap	*soc_ctl_base;
 	const struct sdhci_arasan_soc_ctl_map *soc_ctl_map;
 };

@@ -307,6 +315,31 @@ static const struct of_device_id sdhci_arasan_of_match[] = {
 MODULE_DEVICE_TABLE(of, sdhci_arasan_of_match);
 
 /**
+ * sdhci_arasan_sdcardclk_recalc_rate - Return the card clock rate
+ *
+ * Return the current actual rate of the SD card clock.  This can be used
+ * to communicate with out PHY.
+ *
+ * @hw:			Pointer to the hardware clock structure.
+ * @parent_rate		The parent rate (should be rate of clk_xin).
+ * Returns the card clock rate.
+ */
+static unsigned long sdhci_arasan_sdcardclk_recalc_rate(struct clk_hw *hw,
+						      unsigned long parent_rate)
+
+{
+	struct sdhci_arasan_data *sdhci_arasan =
+		container_of(hw, struct sdhci_arasan_data, sdcardclk_hw);
+	struct sdhci_host *host = sdhci_arasan->host;
+
+	return host->mmc->actual_clock;
+}
+
+static const struct clk_ops arasan_sdcardclk_ops = {
+	.recalc_rate = sdhci_arasan_sdcardclk_recalc_rate,
+};
+
+/**
  * sdhci_arasan_update_baseclkfreq - Set corecfg_baseclkfreq
  *
  * The corecfg_baseclkfreq is supposed to contain the MHz of clk_xin.  This

@@ -345,6 +378,83 @@ static void sdhci_arasan_update_baseclkfreq(struct sdhci_host *host)
 	sdhci_arasan_syscon_write(host, &soc_ctl_map->baseclkfreq, mhz);
 }
 
+/**
+ * sdhci_arasan_register_sdclk - Register the sdclk for a PHY to use
+ *
+ * Some PHY devices need to know what the actual card clock is.  In order for
+ * them to find out, we'll provide a clock through the common clock framework
+ * for them to query.
+ *
+ * Note: without seriously re-architecting SDHCI's clock code and testing on
+ * all platforms, there's no way to create a totally beautiful clock here
+ * with all clock ops implemented.  Instead, we'll just create a clock that can
+ * be queried and set the CLK_GET_RATE_NOCACHE attribute to tell common clock
+ * framework that we're doing things behind its back.  This should be sufficient
+ * to create nice clean device tree bindings and later (if needed) we can try
+ * re-architecting SDHCI if we see some benefit to it.
+ *
+ * @sdhci_arasan:	Our private data structure.
+ * @clk_xin:		Pointer to the functional clock
+ * @dev:		Pointer to our struct device.
+ * Returns 0 on success and error value on error
+ */
+static int sdhci_arasan_register_sdclk(struct sdhci_arasan_data *sdhci_arasan,
+				       struct clk *clk_xin,
+				       struct device *dev)
+{
+	struct device_node *np = dev->of_node;
+	struct clk_init_data sdcardclk_init;
+	const char *parent_clk_name;
+	int ret;
+
+	/* Providing a clock to the PHY is optional; no error if missing */
+	if (!of_find_property(np, "#clock-cells", NULL))
+		return 0;
+
+	ret = of_property_read_string_index(np, "clock-output-names", 0,
+					    &sdcardclk_init.name);
+	if (ret) {
+		dev_err(dev, "DT has #clock-cells but no clock-output-names\n");
+		return ret;
+	}
+
+	parent_clk_name = __clk_get_name(clk_xin);
+	sdcardclk_init.parent_names = &parent_clk_name;
+	sdcardclk_init.num_parents = 1;
+	sdcardclk_init.flags = CLK_GET_RATE_NOCACHE;
+	sdcardclk_init.ops = &arasan_sdcardclk_ops;
+
+	sdhci_arasan->sdcardclk_hw.init = &sdcardclk_init;
+	sdhci_arasan->sdcardclk =
+		devm_clk_register(dev, &sdhci_arasan->sdcardclk_hw);
+	sdhci_arasan->sdcardclk_hw.init = NULL;
+
+	ret = of_clk_add_provider(np, of_clk_src_simple_get,
+				  sdhci_arasan->sdcardclk);
+	if (ret)
+		dev_err(dev, "Failed to add clock provider\n");
+
+	return ret;
+}
+
+/**
+ * sdhci_arasan_unregister_sdclk - Undoes sdhci_arasan_register_sdclk()
+ *
+ * Should be called any time we're exiting and sdhci_arasan_register_sdclk()
+ * returned success.
+ *
+ * @dev:		Pointer to our struct device.
+ */
+static void sdhci_arasan_unregister_sdclk(struct device *dev)
+{
+	struct device_node *np = dev->of_node;
+
+	if (!of_find_property(np, "#clock-cells", NULL))
+		return;
+
+	of_clk_del_provider(dev->of_node);
+}
+
 static int sdhci_arasan_probe(struct platform_device *pdev)
 {
 	int ret;

@@ -362,6 +472,7 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 
 	pltfm_host = sdhci_priv(host);
 	sdhci_arasan = sdhci_pltfm_priv(pltfm_host);
+	sdhci_arasan->host = host;
 
 	match = of_match_node(sdhci_arasan_of_match, pdev->dev.of_node);
 	sdhci_arasan->soc_ctl_map = match->data;

@@ -411,10 +522,14 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 
 	sdhci_arasan_update_baseclkfreq(host);
 
+	ret = sdhci_arasan_register_sdclk(sdhci_arasan, clk_xin, &pdev->dev);
+	if (ret)
+		goto clk_disable_all;
+
 	ret = mmc_of_parse(host->mmc);
 	if (ret) {
 		dev_err(&pdev->dev, "parsing dt failed (%u)\n", ret);
-		goto clk_disable_all;
+		goto unreg_clk;
 	}
 
 	sdhci_arasan->phy = ERR_PTR(-ENODEV);

@@ -425,13 +540,13 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 		if (IS_ERR(sdhci_arasan->phy)) {
 			ret = PTR_ERR(sdhci_arasan->phy);
 			dev_err(&pdev->dev, "No phy for arasan,sdhci-5.1.\n");
-			goto clk_disable_all;
+			goto unreg_clk;
 		}
 
 		ret = phy_init(sdhci_arasan->phy);
 		if (ret < 0) {
 			dev_err(&pdev->dev, "phy_init err.\n");
-			goto clk_disable_all;
+			goto unreg_clk;
 		}
 
 		host->mmc_host_ops.hs400_enhanced_strobe =

@@ -447,6 +562,8 @@ static int sdhci_arasan_probe(struct platform_device *pdev)
 err_add_host:
 	if (!IS_ERR(sdhci_arasan->phy))
 		phy_exit(sdhci_arasan->phy);
+unreg_clk:
+	sdhci_arasan_unregister_sdclk(&pdev->dev);
 clk_disable_all:
 	clk_disable_unprepare(clk_xin);
 clk_dis_ahb:

@@ -469,6 +586,8 @@ static int sdhci_arasan_remove(struct platform_device *pdev)
 		phy_exit(sdhci_arasan->phy);
 	}
 
+	sdhci_arasan_unregister_sdclk(&pdev->dev);
+
 	ret = sdhci_pltfm_unregister(pdev);
 
 	clk_disable_unprepare(clk_ahb);

@@ -220,6 +220,7 @@
 		compatible = "rockchip,rk3399-sdhci-5.1", "arasan,sdhci-5.1";
 		reg = <0x0 0xfe330000 0x0 0x10000>;
 		interrupts = <GIC_SPI 11 IRQ_TYPE_LEVEL_HIGH>;
+		arasan,soc-ctl-syscon = <&grf>;
 		assigned-clocks = <&cru SCLK_EMMC>;
 		assigned-clock-rates = <200000000>;
 		clocks = <&cru SCLK_EMMC>, <&cru ACLK_EMMC>;

@@ -225,8 +225,10 @@
 		assigned-clock-rates = <200000000>;
 		clocks = <&cru SCLK_EMMC>, <&cru ACLK_EMMC>;
 		clock-names = "clk_xin", "clk_ahb";
+		clock-output-names = "emmc_cardclock";
 		phys = <&emmc_phy>;
 		phy-names = "phy_arasan";
+		#clock-cells = <0>;
 		status = "disabled";
 	};
 

@@ -621,6 +623,8 @@
 		emmc_phy: phy at f780 {
 			compatible = "rockchip,rk3399-emmc-phy";
 			reg = <0xf780 0x24>;
+			clocks = <&sdhci>;
+			clock-names = "emmcclk";
 			#phy-cells = <0>;
 			status = "disabled";
 		};

@@ -14,6 +14,7 @@
  * GNU General Public License for more details.
  */
 
+#include <linux/clk.h>
 #include <linux/delay.h>
 #include <linux/mfd/syscon.h>
 #include <linux/module.h>

@@ -78,16 +79,73 @@
 struct rockchip_emmc_phy {
 	unsigned int	reg_offset;
 	struct regmap	*reg_base;
+	struct clk	*emmcclk;
 };
 
-static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
-				   bool on_off)
+static int rockchip_emmc_phy_power(struct phy *phy, bool on_off)
 {
+	struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
 	unsigned int caldone;
 	unsigned int dllrdy;
+	unsigned int freqsel = PHYCTRL_FREQSEL_200M;
 	unsigned long timeout;
 
 	/*
+	 * We purposely get the clock here and not in probe to avoid the
+	 * circular dependency problem.  We expect:
+	 * - PHY driver to probe
+	 * - SDHCI driver to start probe
+	 * - SDHCI driver to register it's clock
+	 * - SDHCI driver to get the PHY
+	 * - SDHCI driver to power on the PHY
+	 */
+	if (!rk_phy->emmcclk) {
+		rk_phy->emmcclk = devm_clk_get(&phy->dev, "emmcclk");
+
+		/* Don't expect defer at this point; try next time */
+		if (PTR_ERR(rk_phy->emmcclk) == -EPROBE_DEFER) {
+			dev_warn(&phy->dev, "Unexpected emmcclk defer\n");
+			rk_phy->emmcclk = NULL;
+		}
+	}
+
+	if (!IS_ERR_OR_NULL(rk_phy->emmcclk)) {
+		unsigned long rate = clk_get_rate(rk_phy->emmcclk);
+		unsigned long ideal_rate;
+		unsigned long diff;
+
+		switch (rate) {
+		case 0 ... 74999999:
+			ideal_rate = 50000000;
+			freqsel = PHYCTRL_FREQSEL_50M;
+			break;
+		case 75000000 ... 124999999:
+			ideal_rate = 100000000;
+			freqsel = PHYCTRL_FREQSEL_100M;
+			break;
+		case 125000000 ... 174999999:
+			ideal_rate = 150000000;
+			freqsel = PHYCTRL_FREQSEL_150M;
+			break;
+		default:
+			ideal_rate = 200000000;
+			break;
+		};
+
+		diff = (rate > ideal_rate) ?
+			rate - ideal_rate : ideal_rate - rate;
+
+		/*
+		 * In order for tuning delays to be accurate we need to be
+		 * pretty spot on for the DLL range, so warn if we're too
+		 * far off.  Also warn if we're above the 200 MHz max.  Don't
+		 * warn for really slow rates since we won't be tuning then.
+		 */
+		if ((rate > 50000000 && diff > 15000000) || (rate > 200000000))
+			dev_warn(&phy->dev, "Unsupported rate: %lu\n", rate);
+	}
+
+	/*
 	 * Keep phyctrl_pdb and phyctrl_endll low to allow
 	 * initialization of CALIO state M/C DFFs
 	 */

@@ -132,6 +190,13 @@ static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
 		return -ETIMEDOUT;
 	}
 
+	/* Set the frequency of the DLL operation */
+	regmap_write(rk_phy->reg_base,
+		     rk_phy->reg_offset + GRF_EMMCPHY_CON0,
+		     HIWORD_UPDATE(freqsel, PHYCTRL_FREQSEL_MASK,
+				   PHYCTRL_FREQSEL_SHIFT));
+
+	/* Turn on the DLL */
 	regmap_write(rk_phy->reg_base,
 		     rk_phy->reg_offset + GRF_EMMCPHY_CON6,
 		     HIWORD_UPDATE(PHYCTRL_ENDLL_ENABLE,

@@ -168,23 +233,14 @@ static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
 
 static int rockchip_emmc_phy_power_off(struct phy *phy)
 {
-	struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
-
 	/* Power down emmc phy analog blocks */
-	return rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_OFF);
+	return rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_OFF);
 }
 
 static int rockchip_emmc_phy_power_on(struct phy *phy)
 {
 	struct rockchip_emmc_phy *rk_phy = phy_get_drvdata(phy);
 
-	/* DLL operation: 200 MHz */
-	regmap_write(rk_phy->reg_base,
-		     rk_phy->reg_offset + GRF_EMMCPHY_CON0,
-		     HIWORD_UPDATE(PHYCTRL_FREQSEL_200M,
-				   PHYCTRL_FREQSEL_MASK,
-				   PHYCTRL_FREQSEL_SHIFT));
-
 	/* Drive impedance: 50 Ohm */
 	regmap_write(rk_phy->reg_base,
 		     rk_phy->reg_offset + GRF_EMMCPHY_CON6,

@@ -207,7 +263,7 @@ static int rockchip_emmc_phy_power_on(struct phy *phy)
 				   PHYCTRL_OTAPDLYSEL_SHIFT));
 
 	/* Power up emmc phy analog blocks */
-	return rockchip_emmc_phy_power(rk_phy, PHYCTRL_PDB_PWR_ON);
+	return rockchip_emmc_phy_power(phy, PHYCTRL_PDB_PWR_ON);
 }
 
 static const struct phy_ops ops = {

@@ -85,6 +85,7 @@ static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
 {
 	unsigned int caldone;
 	unsigned int dllrdy;
+	unsigned long timeout;
 
 	/*
 	 * Keep phyctrl_pdb and phyctrl_endll low to allow

@@ -137,15 +138,26 @@ static int rockchip_emmc_phy_power(struct rockchip_emmc_phy *rk_phy,
 				   PHYCTRL_ENDLL_MASK,
 				   PHYCTRL_ENDLL_SHIFT));
 	/*
-	 * After enable analog DLL circuits, we need an extra 10.2us
-	 * for dll to be ready for work. But according to testing, we
-	 * find some chips need more than 25us.
+	 * After enabling analog DLL circuits docs say that we need 10.2 us if
+	 * our source clock is at 50 MHz and that lock time scales linearly
+	 * with clock speed.  If we are powering on the PHY and the card clock
+	 * is super slow (like 100 kHZ) this could take as long as 5.1 ms as
+	 * per the math: 10.2 us * (50000000 Hz / 100000 Hz) => 5.1 ms
+	 * Hopefully we won't be running at 100 kHz, but we should still make
+	 * sure we wait long enough.
 	 */
-	udelay(30);
-	regmap_read(rk_phy->reg_base,
-		    rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
-		    &dllrdy);
-	dllrdy = (dllrdy >> PHYCTRL_DLLRDY_SHIFT) & PHYCTRL_DLLRDY_MASK;
+	timeout = jiffies + msecs_to_jiffies(10);
+	do {
+		udelay(1);
+
+		regmap_read(rk_phy->reg_base,
+			rk_phy->reg_offset + GRF_EMMCPHY_STATUS,
+			&dllrdy);
+		dllrdy = (dllrdy >> PHYCTRL_DLLRDY_SHIFT) & PHYCTRL_DLLRDY_MASK;
+		if (dllrdy == PHYCTRL_DLLRDY_DONE)
+			break;
+	} while (!time_after(jiffies, timeout));
+
 	if (dllrdy != PHYCTRL_DLLRDY_DONE) {
 		pr_err("rockchip_emmc_phy_power: dllrdy timeout.\n");
 		return -ETIMEDOUT;