drivers/ata/ahci_imx.c - arm/linux-arm64-legacy - Git at Google

 /*
  * copyright (c) 2013 Freescale Semiconductor, Inc.
  * Freescale IMX AHCI SATA platform driver
  *
  * based on the AHCI SATA platform driver by Jeff Garzik and Anton Vorontsov
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms and conditions of the GNU General Public License,
  * version 2, as published by the Free Software Foundation.
  *
  * This program is distributed in the hope it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
  * more details.
  *
  * You should have received a copy of the GNU General Public License along with
  * this program. If not, see <http://www.gnu.org/licenses/>.
  */

 #include <linux/kernel.h>
 #include <linux/module.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
 #include <linux/ahci_platform.h>
 #include <linux/of_device.h>
 #include <linux/mfd/syscon.h>
 #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
 #include <linux/libata.h>
 #include "ahci.h"

 enum {
 	/* Timer 1-ms Register */
 	IMX_TIMER1MS				= 0x00e0,
 	/* Port0 PHY Control Register */
 	IMX_P0PHYCR				= 0x0178,
 	IMX_P0PHYCR_TEST_PDDQ			= 1 << 20,
 	IMX_P0PHYCR_CR_READ			= 1 << 19,
 	IMX_P0PHYCR_CR_WRITE			= 1 << 18,
 	IMX_P0PHYCR_CR_CAP_DATA			= 1 << 17,
 	IMX_P0PHYCR_CR_CAP_ADDR			= 1 << 16,
 	/* Port0 PHY Status Register */
 	IMX_P0PHYSR				= 0x017c,
 	IMX_P0PHYSR_CR_ACK			= 1 << 18,
 	IMX_P0PHYSR_CR_DATA_OUT			= 0xffff << 0,
 	/* Lane0 Output Status Register */
 	IMX_LANE0_OUT_STAT			= 0x2003,
 	IMX_LANE0_OUT_STAT_RX_PLL_STATE		= 1 << 1,
 	/* Clock Reset Register */
 	IMX_CLOCK_RESET				= 0x7f3f,
 	IMX_CLOCK_RESET_RESET			= 1 << 0,
 };

 enum ahci_imx_type {
 	AHCI_IMX53,
 	AHCI_IMX6Q,
 };

 struct imx_ahci_priv {
 	struct platform_device *ahci_pdev;
 	enum ahci_imx_type type;
 	struct clk *sata_clk;
 	struct clk *sata_ref_clk;
 	struct clk *ahb_clk;
 	struct regmap *gpr;
 	bool no_device;
 	bool first_time;
 };

 static int ahci_imx_hotplug;
 module_param_named(hotplug, ahci_imx_hotplug, int, 0644);
 MODULE_PARM_DESC(hotplug, "AHCI IMX hot-plug support (0=Don't support, 1=support)");

 static void ahci_imx_host_stop(struct ata_host *host);

 static int imx_phy_crbit_assert(void __iomem *mmio, u32 bit, bool assert)
 {
 	int timeout = 10;
 	u32 crval;
 	u32 srval;

 	/* Assert or deassert the bit */
 	crval = readl(mmio + IMX_P0PHYCR);
 	if (assert)
 		crval |= bit;
 	else
 		crval &= ~bit;
 	writel(crval, mmio + IMX_P0PHYCR);

 	/* Wait for the cr_ack signal */
 	do {
 		srval = readl(mmio + IMX_P0PHYSR);
 		if ((assert ? srval : ~srval) & IMX_P0PHYSR_CR_ACK)
 			break;
 		usleep_range(100, 200);
 	} while (--timeout);

 	return timeout ? 0 : -ETIMEDOUT;
 }

 static int imx_phy_reg_addressing(u16 addr, void __iomem *mmio)
 {
 	u32 crval = addr;
 	int ret;

 	/* Supply the address on cr_data_in */
 	writel(crval, mmio + IMX_P0PHYCR);

 	/* Assert the cr_cap_addr signal */
 	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_CAP_ADDR, true);
 	if (ret)
 		return ret;

 	/* Deassert cr_cap_addr */
 	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_CAP_ADDR, false);
 	if (ret)
 		return ret;

 	return 0;
 }

 static int imx_phy_reg_write(u16 val, void __iomem *mmio)
 {
 	u32 crval = val;
 	int ret;

 	/* Supply the data on cr_data_in */
 	writel(crval, mmio + IMX_P0PHYCR);

 	/* Assert the cr_cap_data signal */
 	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_CAP_DATA, true);
 	if (ret)
 		return ret;

 	/* Deassert cr_cap_data */
 	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_CAP_DATA, false);
 	if (ret)
 		return ret;

 	if (val & IMX_CLOCK_RESET_RESET) {
 		/*
 		 * In case we're resetting the phy, it's unable to acknowledge,
 		 * so we return immediately here.
 		 */
 		crval |= IMX_P0PHYCR_CR_WRITE;
 		writel(crval, mmio + IMX_P0PHYCR);
 		goto out;
 	}

 	/* Assert the cr_write signal */
 	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_WRITE, true);
 	if (ret)
 		return ret;

 	/* Deassert cr_write */
 	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_WRITE, false);
 	if (ret)
 		return ret;

 out:
 	return 0;
 }

 static int imx_phy_reg_read(u16 *val, void __iomem *mmio)
 {
 	int ret;

 	/* Assert the cr_read signal */
 	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_READ, true);
 	if (ret)
 		return ret;

 	/* Capture the data from cr_data_out[] */
 	*val = readl(mmio + IMX_P0PHYSR) & IMX_P0PHYSR_CR_DATA_OUT;

 	/* Deassert cr_read */
 	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_READ, false);
 	if (ret)
 		return ret;

 	return 0;
 }

 static int imx_sata_phy_reset(struct ahci_host_priv *hpriv)
 {
 	void __iomem *mmio = hpriv->mmio;
 	int timeout = 10;
 	u16 val;
 	int ret;

 	/* Reset SATA PHY by setting RESET bit of PHY register CLOCK_RESET */
 	ret = imx_phy_reg_addressing(IMX_CLOCK_RESET, mmio);
 	if (ret)
 		return ret;
 	ret = imx_phy_reg_write(IMX_CLOCK_RESET_RESET, mmio);
 	if (ret)
 		return ret;

 	/* Wait for PHY RX_PLL to be stable */
 	do {
 		usleep_range(100, 200);
 		ret = imx_phy_reg_addressing(IMX_LANE0_OUT_STAT, mmio);
 		if (ret)
 			return ret;
 		ret = imx_phy_reg_read(&val, mmio);
 		if (ret)
 			return ret;
 		if (val & IMX_LANE0_OUT_STAT_RX_PLL_STATE)
 			break;
 	} while (--timeout);

 	return timeout ? 0 : -ETIMEDOUT;
 }

 static int imx_sata_enable(struct ahci_host_priv *hpriv)
 {
 	struct imx_ahci_priv *imxpriv = hpriv->plat_data;
 	struct device *dev = &imxpriv->ahci_pdev->dev;
 	int ret;

 	if (imxpriv->no_device)
 		return 0;

 	if (hpriv->target_pwr) {
 		ret = regulator_enable(hpriv->target_pwr);
 		if (ret)
 			return ret;
 	}

 	ret = clk_prepare_enable(imxpriv->sata_ref_clk);
 	if (ret < 0)
 		goto disable_regulator;

 	if (imxpriv->type == AHCI_IMX6Q) {
 		/*
 		 * set PHY Paremeters, two steps to configure the GPR13,
 		 * one write for rest of parameters, mask of first write
 		 * is 0x07ffffff, and the other one write for setting
 		 * the mpll_clk_en.
 		 */
 		regmap_update_bits(imxpriv->gpr, IOMUXC_GPR13,
 				   IMX6Q_GPR13_SATA_RX_EQ_VAL_MASK |
 				   IMX6Q_GPR13_SATA_RX_LOS_LVL_MASK |
 				   IMX6Q_GPR13_SATA_RX_DPLL_MODE_MASK |
 				   IMX6Q_GPR13_SATA_SPD_MODE_MASK |
 				   IMX6Q_GPR13_SATA_MPLL_SS_EN |
 				   IMX6Q_GPR13_SATA_TX_ATTEN_MASK |
 				   IMX6Q_GPR13_SATA_TX_BOOST_MASK |
 				   IMX6Q_GPR13_SATA_TX_LVL_MASK |
 				   IMX6Q_GPR13_SATA_MPLL_CLK_EN |
 				   IMX6Q_GPR13_SATA_TX_EDGE_RATE,
 				   IMX6Q_GPR13_SATA_RX_EQ_VAL_3_0_DB |
 				   IMX6Q_GPR13_SATA_RX_LOS_LVL_SATA2M |
 				   IMX6Q_GPR13_SATA_RX_DPLL_MODE_2P_4F |
 				   IMX6Q_GPR13_SATA_SPD_MODE_3P0G |
 				   IMX6Q_GPR13_SATA_MPLL_SS_EN |
 				   IMX6Q_GPR13_SATA_TX_ATTEN_9_16 |
 				   IMX6Q_GPR13_SATA_TX_BOOST_3_33_DB |
 				   IMX6Q_GPR13_SATA_TX_LVL_1_025_V);
 		regmap_update_bits(imxpriv->gpr, IOMUXC_GPR13,
 				   IMX6Q_GPR13_SATA_MPLL_CLK_EN,
 				   IMX6Q_GPR13_SATA_MPLL_CLK_EN);

 		usleep_range(100, 200);

 		ret = imx_sata_phy_reset(hpriv);
 		if (ret) {
 			dev_err(dev, "failed to reset phy: %d\n", ret);
 			goto disable_regulator;
 		}
 	}

 	usleep_range(1000, 2000);

 	return 0;

 disable_regulator:
 	if (hpriv->target_pwr)
 		regulator_disable(hpriv->target_pwr);

 	return ret;
 }

 static void imx_sata_disable(struct ahci_host_priv *hpriv)
 {
 	struct imx_ahci_priv *imxpriv = hpriv->plat_data;

 	if (imxpriv->no_device)
 		return;

 	if (imxpriv->type == AHCI_IMX6Q) {
 		regmap_update_bits(imxpriv->gpr, IOMUXC_GPR13,
 				   IMX6Q_GPR13_SATA_MPLL_CLK_EN,
 				   !IMX6Q_GPR13_SATA_MPLL_CLK_EN);
 	}

 	clk_disable_unprepare(imxpriv->sata_ref_clk);

 	if (hpriv->target_pwr)
 		regulator_disable(hpriv->target_pwr);
 }

 static void ahci_imx_error_handler(struct ata_port *ap)
 {
 	u32 reg_val;
 	struct ata_device *dev;
 	struct ata_host *host = dev_get_drvdata(ap->dev);
 	struct ahci_host_priv *hpriv = host->private_data;
 	void __iomem *mmio = hpriv->mmio;
 	struct imx_ahci_priv *imxpriv = hpriv->plat_data;

 	ahci_error_handler(ap);

 	if (!(imxpriv->first_time) || ahci_imx_hotplug)
 		return;

 	imxpriv->first_time = false;

 	ata_for_each_dev(dev, &ap->link, ENABLED)
 		return;
 	/*
 	 * Disable link to save power.  An imx ahci port can't be recovered
 	 * without full reset once the pddq mode is enabled making it
 	 * impossible to use as part of libata LPM.
 	 */
 	reg_val = readl(mmio + IMX_P0PHYCR);
 	writel(reg_val | IMX_P0PHYCR_TEST_PDDQ, mmio + IMX_P0PHYCR);
 	imx_sata_disable(hpriv);
 	imxpriv->no_device = true;

 	dev_info(ap->dev, "no device found, disabling link.\n");
 	dev_info(ap->dev, "pass " MODULE_PARAM_PREFIX ".hotplug=1 to enable hotplug\n");
 }

 static int ahci_imx_softreset(struct ata_link *link, unsigned int *class,
 		       unsigned long deadline)
 {
 	struct ata_port *ap = link->ap;
 	struct ata_host *host = dev_get_drvdata(ap->dev);
 	struct ahci_host_priv *hpriv = host->private_data;
 	struct imx_ahci_priv *imxpriv = hpriv->plat_data;
 	int ret = -EIO;

 	if (imxpriv->type == AHCI_IMX53)
 		ret = ahci_pmp_retry_srst_ops.softreset(link, class, deadline);
 	else if (imxpriv->type == AHCI_IMX6Q)
 		ret = ahci_ops.softreset(link, class, deadline);

 	return ret;
 }

 static struct ata_port_operations ahci_imx_ops = {
 	.inherits	= &ahci_ops,
 	.host_stop	= ahci_imx_host_stop,
 	.error_handler	= ahci_imx_error_handler,
 	.softreset	= ahci_imx_softreset,
 };

 static const struct ata_port_info ahci_imx_port_info = {
 	.flags		= AHCI_FLAG_COMMON,
 	.pio_mask	= ATA_PIO4,
 	.udma_mask	= ATA_UDMA6,
 	.port_ops	= &ahci_imx_ops,
 };

 static const struct of_device_id imx_ahci_of_match[] = {
 	{ .compatible = "fsl,imx53-ahci", .data = (void *)AHCI_IMX53 },
 	{ .compatible = "fsl,imx6q-ahci", .data = (void *)AHCI_IMX6Q },
 	{},
 };
 MODULE_DEVICE_TABLE(of, imx_ahci_of_match);

 static int imx_ahci_probe(struct platform_device *pdev)
 {
 	struct device *dev = &pdev->dev;
 	const struct of_device_id *of_id;
 	struct ahci_host_priv *hpriv;
 	struct imx_ahci_priv *imxpriv;
 	unsigned int reg_val;
 	int ret;

 	of_id = of_match_device(imx_ahci_of_match, dev);
 	if (!of_id)
 		return -EINVAL;

 	imxpriv = devm_kzalloc(dev, sizeof(*imxpriv), GFP_KERNEL);
 	if (!imxpriv)
 		return -ENOMEM;

 	imxpriv->ahci_pdev = pdev;
 	imxpriv->no_device = false;
 	imxpriv->first_time = true;
 	imxpriv->type = (enum ahci_imx_type)of_id->data;

 	imxpriv->sata_clk = devm_clk_get(dev, "sata");
 	if (IS_ERR(imxpriv->sata_clk)) {
 		dev_err(dev, "can't get sata clock.\n");
 		return PTR_ERR(imxpriv->sata_clk);
 	}

 	imxpriv->sata_ref_clk = devm_clk_get(dev, "sata_ref");
 	if (IS_ERR(imxpriv->sata_ref_clk)) {
 		dev_err(dev, "can't get sata_ref clock.\n");
 		return PTR_ERR(imxpriv->sata_ref_clk);
 	}

 	imxpriv->ahb_clk = devm_clk_get(dev, "ahb");
 	if (IS_ERR(imxpriv->ahb_clk)) {
 		dev_err(dev, "can't get ahb clock.\n");
 		return PTR_ERR(imxpriv->ahb_clk);
 	}

 	if (imxpriv->type == AHCI_IMX6Q) {
 		imxpriv->gpr = syscon_regmap_lookup_by_compatible(
 							"fsl,imx6q-iomuxc-gpr");
 		if (IS_ERR(imxpriv->gpr)) {
 			dev_err(dev,
 				"failed to find fsl,imx6q-iomux-gpr regmap\n");
 			return PTR_ERR(imxpriv->gpr);
 		}
 	}

 	hpriv = ahci_platform_get_resources(pdev);
 	if (IS_ERR(hpriv))
 		return PTR_ERR(hpriv);

 	hpriv->plat_data = imxpriv;

 	ret = clk_prepare_enable(imxpriv->sata_clk);
 	if (ret)
 		return ret;

 	ret = imx_sata_enable(hpriv);
 	if (ret)
 		goto disable_clk;

 	/*
 	 * Configure the HWINIT bits of the HOST_CAP and HOST_PORTS_IMPL,
 	 * and IP vendor specific register IMX_TIMER1MS.
 	 * Configure CAP_SSS (support stagered spin up).
 	 * Implement the port0.
 	 * Get the ahb clock rate, and configure the TIMER1MS register.
 	 */
 	reg_val = readl(hpriv->mmio + HOST_CAP);
 	if (!(reg_val & HOST_CAP_SSS)) {
 		reg_val |= HOST_CAP_SSS;
 		writel(reg_val, hpriv->mmio + HOST_CAP);
 	}
 	reg_val = readl(hpriv->mmio + HOST_PORTS_IMPL);
 	if (!(reg_val & 0x1)) {
 		reg_val |= 0x1;
 		writel(reg_val, hpriv->mmio + HOST_PORTS_IMPL);
 	}

 	reg_val = clk_get_rate(imxpriv->ahb_clk) / 1000;
 	writel(reg_val, hpriv->mmio + IMX_TIMER1MS);

 	ret = ahci_platform_init_host(pdev, hpriv, &ahci_imx_port_info,
 				      0, 0, 0);
 	if (ret)
 		goto disable_sata;

 	return 0;

 disable_sata:
 	imx_sata_disable(hpriv);
 disable_clk:
 	clk_disable_unprepare(imxpriv->sata_clk);
 	return ret;
 }

 static void ahci_imx_host_stop(struct ata_host *host)
 {
 	struct ahci_host_priv *hpriv = host->private_data;
 	struct imx_ahci_priv *imxpriv = hpriv->plat_data;

 	imx_sata_disable(hpriv);
 	clk_disable_unprepare(imxpriv->sata_clk);
 }

 #ifdef CONFIG_PM_SLEEP
 static int imx_ahci_suspend(struct device *dev)
 {
 	struct ata_host *host = dev_get_drvdata(dev);
 	struct ahci_host_priv *hpriv = host->private_data;
 	int ret;

 	ret = ahci_platform_suspend_host(dev);
 	if (ret)
 		return ret;

 	imx_sata_disable(hpriv);

 	return 0;
 }

 static int imx_ahci_resume(struct device *dev)
 {
 	struct ata_host *host = dev_get_drvdata(dev);
 	struct ahci_host_priv *hpriv = host->private_data;
 	int ret;

 	ret = imx_sata_enable(hpriv);
 	if (ret)
 		return ret;

 	return ahci_platform_resume_host(dev);
 }
 #endif

 static SIMPLE_DEV_PM_OPS(ahci_imx_pm_ops, imx_ahci_suspend, imx_ahci_resume);

 static struct platform_driver imx_ahci_driver = {
 	.probe = imx_ahci_probe,
 	.remove = ata_platform_remove_one,
 	.driver = {
 		.name = "ahci-imx",
 		.owner = THIS_MODULE,
 		.of_match_table = imx_ahci_of_match,
 		.pm = &ahci_imx_pm_ops,
 	},
 };
 module_platform_driver(imx_ahci_driver);

 MODULE_DESCRIPTION("Freescale i.MX AHCI SATA platform driver");
 MODULE_AUTHOR("Richard Zhu <Hong-Xing.Zhu@freescale.com>");
 MODULE_LICENSE("GPL");
 MODULE_ALIAS("ahci:imx");
	/*
	* copyright (c) 2013 Freescale Semiconductor, Inc.
	* Freescale IMX AHCI SATA platform driver
	*
	* based on the AHCI SATA platform driver by Jeff Garzik and Anton Vorontsov
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms and conditions of the GNU General Public License,
	* version 2, as published by the Free Software Foundation.
	*
	* This program is distributed in the hope it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	* more details.
	*
	* You should have received a copy of the GNU General Public License along with
	* this program. If not, see <http://www.gnu.org/licenses/>.
	*/

	#include <linux/kernel.h>
	#include <linux/module.h>
	#include <linux/platform_device.h>
	#include <linux/regmap.h>
	#include <linux/ahci_platform.h>
	#include <linux/of_device.h>
	#include <linux/mfd/syscon.h>
	#include <linux/mfd/syscon/imx6q-iomuxc-gpr.h>
	#include <linux/libata.h>
	#include "ahci.h"

	enum {
	/* Timer 1-ms Register */
	IMX_TIMER1MS = 0x00e0,
	/* Port0 PHY Control Register */
	IMX_P0PHYCR = 0x0178,
	IMX_P0PHYCR_TEST_PDDQ = 1 << 20,
	IMX_P0PHYCR_CR_READ = 1 << 19,
	IMX_P0PHYCR_CR_WRITE = 1 << 18,
	IMX_P0PHYCR_CR_CAP_DATA = 1 << 17,
	IMX_P0PHYCR_CR_CAP_ADDR = 1 << 16,
	/* Port0 PHY Status Register */
	IMX_P0PHYSR = 0x017c,
	IMX_P0PHYSR_CR_ACK = 1 << 18,
	IMX_P0PHYSR_CR_DATA_OUT = 0xffff << 0,
	/* Lane0 Output Status Register */
	IMX_LANE0_OUT_STAT = 0x2003,
	IMX_LANE0_OUT_STAT_RX_PLL_STATE = 1 << 1,
	/* Clock Reset Register */
	IMX_CLOCK_RESET = 0x7f3f,
	IMX_CLOCK_RESET_RESET = 1 << 0,
	};

	enum ahci_imx_type {
	AHCI_IMX53,
	AHCI_IMX6Q,
	};

	struct imx_ahci_priv {
	struct platform_device *ahci_pdev;
	enum ahci_imx_type type;
	struct clk *sata_clk;
	struct clk *sata_ref_clk;
	struct clk *ahb_clk;
	struct regmap *gpr;
	bool no_device;
	bool first_time;
	};

	static int ahci_imx_hotplug;
	module_param_named(hotplug, ahci_imx_hotplug, int, 0644);
	MODULE_PARM_DESC(hotplug, "AHCI IMX hot-plug support (0=Don't support, 1=support)");

	static void ahci_imx_host_stop(struct ata_host *host);

	static int imx_phy_crbit_assert(void __iomem *mmio, u32 bit, bool assert)
	{
	int timeout = 10;
	u32 crval;
	u32 srval;

	/* Assert or deassert the bit */
	crval = readl(mmio + IMX_P0PHYCR);
	if (assert)
	crval \|= bit;
	else
	crval &= ~bit;
	writel(crval, mmio + IMX_P0PHYCR);

	/* Wait for the cr_ack signal */
	do {
	srval = readl(mmio + IMX_P0PHYSR);
	if ((assert ? srval : ~srval) & IMX_P0PHYSR_CR_ACK)
	break;
	usleep_range(100, 200);
	} while (--timeout);

	return timeout ? 0 : -ETIMEDOUT;
	}

	static int imx_phy_reg_addressing(u16 addr, void __iomem *mmio)
	{
	u32 crval = addr;
	int ret;

	/* Supply the address on cr_data_in */
	writel(crval, mmio + IMX_P0PHYCR);

	/* Assert the cr_cap_addr signal */
	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_CAP_ADDR, true);
	if (ret)
	return ret;

	/* Deassert cr_cap_addr */
	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_CAP_ADDR, false);
	if (ret)
	return ret;

	return 0;
	}

	static int imx_phy_reg_write(u16 val, void __iomem *mmio)
	{
	u32 crval = val;
	int ret;

	/* Supply the data on cr_data_in */
	writel(crval, mmio + IMX_P0PHYCR);

	/* Assert the cr_cap_data signal */
	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_CAP_DATA, true);
	if (ret)
	return ret;

	/* Deassert cr_cap_data */
	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_CAP_DATA, false);
	if (ret)
	return ret;

	if (val & IMX_CLOCK_RESET_RESET) {
	/*
	* In case we're resetting the phy, it's unable to acknowledge,
	* so we return immediately here.
	*/
	crval \|= IMX_P0PHYCR_CR_WRITE;
	writel(crval, mmio + IMX_P0PHYCR);
	goto out;
	}

	/* Assert the cr_write signal */
	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_WRITE, true);
	if (ret)
	return ret;

	/* Deassert cr_write */
	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_WRITE, false);
	if (ret)
	return ret;

	out:
	return 0;
	}

	static int imx_phy_reg_read(u16 val, void __iomem mmio)
	{
	int ret;

	/* Assert the cr_read signal */
	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_READ, true);
	if (ret)
	return ret;

	/* Capture the data from cr_data_out[] */
	*val = readl(mmio + IMX_P0PHYSR) & IMX_P0PHYSR_CR_DATA_OUT;

	/* Deassert cr_read */
	ret = imx_phy_crbit_assert(mmio, IMX_P0PHYCR_CR_READ, false);
	if (ret)
	return ret;

	return 0;
	}

	static int imx_sata_phy_reset(struct ahci_host_priv *hpriv)
	{
	void __iomem *mmio = hpriv->mmio;
	int timeout = 10;
	u16 val;
	int ret;

	/* Reset SATA PHY by setting RESET bit of PHY register CLOCK_RESET */
	ret = imx_phy_reg_addressing(IMX_CLOCK_RESET, mmio);
	if (ret)
	return ret;
	ret = imx_phy_reg_write(IMX_CLOCK_RESET_RESET, mmio);
	if (ret)
	return ret;

	/* Wait for PHY RX_PLL to be stable */
	do {
	usleep_range(100, 200);
	ret = imx_phy_reg_addressing(IMX_LANE0_OUT_STAT, mmio);
	if (ret)
	return ret;
	ret = imx_phy_reg_read(&val, mmio);
	if (ret)
	return ret;
	if (val & IMX_LANE0_OUT_STAT_RX_PLL_STATE)
	break;
	} while (--timeout);

	return timeout ? 0 : -ETIMEDOUT;
	}

	static int imx_sata_enable(struct ahci_host_priv *hpriv)
	{
	struct imx_ahci_priv *imxpriv = hpriv->plat_data;
	struct device *dev = &imxpriv->ahci_pdev->dev;
	int ret;

	if (imxpriv->no_device)
	return 0;

	if (hpriv->target_pwr) {
	ret = regulator_enable(hpriv->target_pwr);
	if (ret)
	return ret;
	}

	ret = clk_prepare_enable(imxpriv->sata_ref_clk);
	if (ret < 0)
	goto disable_regulator;

	if (imxpriv->type == AHCI_IMX6Q) {
	/*
	* set PHY Paremeters, two steps to configure the GPR13,
	* one write for rest of parameters, mask of first write
	* is 0x07ffffff, and the other one write for setting
	* the mpll_clk_en.
	*/
	regmap_update_bits(imxpriv->gpr, IOMUXC_GPR13,
	IMX6Q_GPR13_SATA_RX_EQ_VAL_MASK \|
	IMX6Q_GPR13_SATA_RX_LOS_LVL_MASK \|
	IMX6Q_GPR13_SATA_RX_DPLL_MODE_MASK \|
	IMX6Q_GPR13_SATA_SPD_MODE_MASK \|
	IMX6Q_GPR13_SATA_MPLL_SS_EN \|
	IMX6Q_GPR13_SATA_TX_ATTEN_MASK \|
	IMX6Q_GPR13_SATA_TX_BOOST_MASK \|
	IMX6Q_GPR13_SATA_TX_LVL_MASK \|
	IMX6Q_GPR13_SATA_MPLL_CLK_EN \|
	IMX6Q_GPR13_SATA_TX_EDGE_RATE,
	IMX6Q_GPR13_SATA_RX_EQ_VAL_3_0_DB \|
	IMX6Q_GPR13_SATA_RX_LOS_LVL_SATA2M \|
	IMX6Q_GPR13_SATA_RX_DPLL_MODE_2P_4F \|
	IMX6Q_GPR13_SATA_SPD_MODE_3P0G \|
	IMX6Q_GPR13_SATA_MPLL_SS_EN \|
	IMX6Q_GPR13_SATA_TX_ATTEN_9_16 \|
	IMX6Q_GPR13_SATA_TX_BOOST_3_33_DB \|
	IMX6Q_GPR13_SATA_TX_LVL_1_025_V);
	regmap_update_bits(imxpriv->gpr, IOMUXC_GPR13,
	IMX6Q_GPR13_SATA_MPLL_CLK_EN,
	IMX6Q_GPR13_SATA_MPLL_CLK_EN);

	usleep_range(100, 200);

	ret = imx_sata_phy_reset(hpriv);
	if (ret) {
	dev_err(dev, "failed to reset phy: %d\n", ret);
	goto disable_regulator;
	}
	}

	usleep_range(1000, 2000);

	return 0;

	disable_regulator:
	if (hpriv->target_pwr)
	regulator_disable(hpriv->target_pwr);

	return ret;
	}

	static void imx_sata_disable(struct ahci_host_priv *hpriv)
	{
	struct imx_ahci_priv *imxpriv = hpriv->plat_data;

	if (imxpriv->no_device)
	return;

	if (imxpriv->type == AHCI_IMX6Q) {
	regmap_update_bits(imxpriv->gpr, IOMUXC_GPR13,
	IMX6Q_GPR13_SATA_MPLL_CLK_EN,
	!IMX6Q_GPR13_SATA_MPLL_CLK_EN);
	}

	clk_disable_unprepare(imxpriv->sata_ref_clk);

	if (hpriv->target_pwr)
	regulator_disable(hpriv->target_pwr);
	}

	static void ahci_imx_error_handler(struct ata_port *ap)
	{
	u32 reg_val;
	struct ata_device *dev;
	struct ata_host *host = dev_get_drvdata(ap->dev);
	struct ahci_host_priv *hpriv = host->private_data;
	void __iomem *mmio = hpriv->mmio;
	struct imx_ahci_priv *imxpriv = hpriv->plat_data;

	ahci_error_handler(ap);

	if (!(imxpriv->first_time) \|\| ahci_imx_hotplug)
	return;

	imxpriv->first_time = false;

	ata_for_each_dev(dev, &ap->link, ENABLED)
	return;
	/*
	* Disable link to save power. An imx ahci port can't be recovered
	* without full reset once the pddq mode is enabled making it
	* impossible to use as part of libata LPM.
	*/
	reg_val = readl(mmio + IMX_P0PHYCR);
	writel(reg_val \| IMX_P0PHYCR_TEST_PDDQ, mmio + IMX_P0PHYCR);
	imx_sata_disable(hpriv);
	imxpriv->no_device = true;

	dev_info(ap->dev, "no device found, disabling link.\n");
	dev_info(ap->dev, "pass " MODULE_PARAM_PREFIX ".hotplug=1 to enable hotplug\n");
	}

	static int ahci_imx_softreset(struct ata_link link, unsigned int class,
	unsigned long deadline)
	{
	struct ata_port *ap = link->ap;
	struct ata_host *host = dev_get_drvdata(ap->dev);
	struct ahci_host_priv *hpriv = host->private_data;
	struct imx_ahci_priv *imxpriv = hpriv->plat_data;
	int ret = -EIO;

	if (imxpriv->type == AHCI_IMX53)
	ret = ahci_pmp_retry_srst_ops.softreset(link, class, deadline);
	else if (imxpriv->type == AHCI_IMX6Q)
	ret = ahci_ops.softreset(link, class, deadline);

	return ret;
	}

	static struct ata_port_operations ahci_imx_ops = {
	.inherits = &ahci_ops,
	.host_stop = ahci_imx_host_stop,
	.error_handler = ahci_imx_error_handler,
	.softreset = ahci_imx_softreset,
	};

	static const struct ata_port_info ahci_imx_port_info = {
	.flags = AHCI_FLAG_COMMON,
	.pio_mask = ATA_PIO4,
	.udma_mask = ATA_UDMA6,
	.port_ops = &ahci_imx_ops,
	};

	static const struct of_device_id imx_ahci_of_match[] = {
	{ .compatible = "fsl,imx53-ahci", .data = (void *)AHCI_IMX53 },
	{ .compatible = "fsl,imx6q-ahci", .data = (void *)AHCI_IMX6Q },
	{},
	};
	MODULE_DEVICE_TABLE(of, imx_ahci_of_match);

	static int imx_ahci_probe(struct platform_device *pdev)
	{
	struct device *dev = &pdev->dev;
	const struct of_device_id *of_id;
	struct ahci_host_priv *hpriv;
	struct imx_ahci_priv *imxpriv;
	unsigned int reg_val;
	int ret;

	of_id = of_match_device(imx_ahci_of_match, dev);
	if (!of_id)
	return -EINVAL;

	imxpriv = devm_kzalloc(dev, sizeof(*imxpriv), GFP_KERNEL);
	if (!imxpriv)
	return -ENOMEM;

	imxpriv->ahci_pdev = pdev;
	imxpriv->no_device = false;
	imxpriv->first_time = true;
	imxpriv->type = (enum ahci_imx_type)of_id->data;

	imxpriv->sata_clk = devm_clk_get(dev, "sata");
	if (IS_ERR(imxpriv->sata_clk)) {
	dev_err(dev, "can't get sata clock.\n");
	return PTR_ERR(imxpriv->sata_clk);
	}

	imxpriv->sata_ref_clk = devm_clk_get(dev, "sata_ref");
	if (IS_ERR(imxpriv->sata_ref_clk)) {
	dev_err(dev, "can't get sata_ref clock.\n");
	return PTR_ERR(imxpriv->sata_ref_clk);
	}

	imxpriv->ahb_clk = devm_clk_get(dev, "ahb");
	if (IS_ERR(imxpriv->ahb_clk)) {
	dev_err(dev, "can't get ahb clock.\n");
	return PTR_ERR(imxpriv->ahb_clk);
	}

	if (imxpriv->type == AHCI_IMX6Q) {
	imxpriv->gpr = syscon_regmap_lookup_by_compatible(
	"fsl,imx6q-iomuxc-gpr");
	if (IS_ERR(imxpriv->gpr)) {
	dev_err(dev,
	"failed to find fsl,imx6q-iomux-gpr regmap\n");
	return PTR_ERR(imxpriv->gpr);
	}
	}

	hpriv = ahci_platform_get_resources(pdev);
	if (IS_ERR(hpriv))
	return PTR_ERR(hpriv);

	hpriv->plat_data = imxpriv;

	ret = clk_prepare_enable(imxpriv->sata_clk);
	if (ret)
	return ret;

	ret = imx_sata_enable(hpriv);
	if (ret)
	goto disable_clk;

	/*
	* Configure the HWINIT bits of the HOST_CAP and HOST_PORTS_IMPL,
	* and IP vendor specific register IMX_TIMER1MS.
	* Configure CAP_SSS (support stagered spin up).
	* Implement the port0.
	* Get the ahb clock rate, and configure the TIMER1MS register.
	*/
	reg_val = readl(hpriv->mmio + HOST_CAP);
	if (!(reg_val & HOST_CAP_SSS)) {
	reg_val \|= HOST_CAP_SSS;
	writel(reg_val, hpriv->mmio + HOST_CAP);
	}
	reg_val = readl(hpriv->mmio + HOST_PORTS_IMPL);
	if (!(reg_val & 0x1)) {
	reg_val \|= 0x1;
	writel(reg_val, hpriv->mmio + HOST_PORTS_IMPL);
	}

	reg_val = clk_get_rate(imxpriv->ahb_clk) / 1000;
	writel(reg_val, hpriv->mmio + IMX_TIMER1MS);

	ret = ahci_platform_init_host(pdev, hpriv, &ahci_imx_port_info,
	0, 0, 0);
	if (ret)
	goto disable_sata;

	return 0;

	disable_sata:
	imx_sata_disable(hpriv);
	disable_clk:
	clk_disable_unprepare(imxpriv->sata_clk);
	return ret;
	}

	static void ahci_imx_host_stop(struct ata_host *host)
	{
	struct ahci_host_priv *hpriv = host->private_data;
	struct imx_ahci_priv *imxpriv = hpriv->plat_data;

	imx_sata_disable(hpriv);
	clk_disable_unprepare(imxpriv->sata_clk);
	}

	#ifdef CONFIG_PM_SLEEP
	static int imx_ahci_suspend(struct device *dev)
	{
	struct ata_host *host = dev_get_drvdata(dev);
	struct ahci_host_priv *hpriv = host->private_data;
	int ret;

	ret = ahci_platform_suspend_host(dev);
	if (ret)
	return ret;

	imx_sata_disable(hpriv);

	return 0;
	}

	static int imx_ahci_resume(struct device *dev)
	{
	struct ata_host *host = dev_get_drvdata(dev);
	struct ahci_host_priv *hpriv = host->private_data;
	int ret;

	ret = imx_sata_enable(hpriv);
	if (ret)
	return ret;

	return ahci_platform_resume_host(dev);
	}
	#endif

	static SIMPLE_DEV_PM_OPS(ahci_imx_pm_ops, imx_ahci_suspend, imx_ahci_resume);

	static struct platform_driver imx_ahci_driver = {
	.probe = imx_ahci_probe,
	.remove = ata_platform_remove_one,
	.driver = {
	.name = "ahci-imx",
	.owner = THIS_MODULE,
	.of_match_table = imx_ahci_of_match,
	.pm = &ahci_imx_pm_ops,
	},
	};
	module_platform_driver(imx_ahci_driver);

	MODULE_DESCRIPTION("Freescale i.MX AHCI SATA platform driver");
	MODULE_AUTHOR("Richard Zhu <Hong-Xing.Zhu@freescale.com>");
	MODULE_LICENSE("GPL");
	MODULE_ALIAS("ahci:imx");