phy: qcom: Add driver for QCOM IPQ806x SATA PHY

Add a PHY driver for uses with AHCI based SATA controller driver on the
IPQ806x family of SoCs.

Signed-off-by: Kumar Gala <galak@codeaurora.org>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>

3 files changed, 219 insertions, 0 deletions

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 1704fd4be99e..3e251aa64ffd 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -191,4 +191,11 @@ config PHY_QCOM_APQ8064_SATA
         depends on OF
         select GENERIC_PHY
 
+config PHY_QCOM_IPQ806X_SATA
+        tristate "Qualcomm IPQ806x SATA SerDes/PHY driver"
+        depends on ARCH_QCOM
+        depends on HAS_IOMEM
+        depends on OF
+        select GENERIC_PHY
+
 endmenu
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index 3c2ad5915be2..54ab9785932c 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -23,3 +23,4 @@ phy-exynos-usb2-$(CONFIG_PHY_EXYNOS5250_USB2)	+= phy-exynos5250-usb2.o
 obj-$(CONFIG_PHY_EXYNOS5_USBDRD)        += phy-exynos5-usbdrd.o
 obj-$(CONFIG_PHY_XGENE)                 += phy-xgene.o
 obj-$(CONFIG_PHY_QCOM_APQ8064_SATA)     += phy-qcom-apq8064-sata.o
+obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA)     += phy-qcom-ipq806x-sata.o
diff --git a/drivers/phy/phy-qcom-ipq806x-sata.c b/drivers/phy/phy-qcom-ipq806x-sata.c
new file mode 100644
index 000000000000..909b5a87fc6a
--- /dev/null
+++ b/drivers/phy/phy-qcom-ipq806x-sata.c
@@ -0,0 +1,211 @@
+/*
+ * Copyright (c) 2014, The Linux Foundation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 and
+ * only version 2 as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that 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.
+ */
+
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/time.h>
+#include <linux/delay.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/platform_device.h>
+#include <linux/phy/phy.h>
+
+struct qcom_ipq806x_sata_phy {
+        void __iomem *mmio;
+        struct clk *cfg_clk;
+        struct device *dev;
+};
+
+#define __set(v, a, b)  (((v) << (b)) & GENMASK(a, b))
+
+#define SATA_PHY_P0_PARAM0              0x200
+#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3(x)        __set(x, 17, 12)
+#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3_MASK      GENMASK(17, 12)
+#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2(x)        __set(x, 11, 6)
+#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2_MASK      GENMASK(11, 6)
+#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1(x)        __set(x, 5, 0)
+#define SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1_MASK      GENMASK(5, 0)
+
+#define SATA_PHY_P0_PARAM1              0x204
+#define SATA_PHY_P0_PARAM1_RESERVED_BITS31_21(x)        __set(x, 31, 21)
+#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3(x)      __set(x, 20, 14)
+#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3_MASK    GENMASK(20, 14)
+#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2(x)      __set(x, 13, 7)
+#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2_MASK    GENMASK(13, 7)
+#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1(x)      __set(x, 6, 0)
+#define SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1_MASK    GENMASK(6, 0)
+
+#define SATA_PHY_P0_PARAM2              0x208
+#define SATA_PHY_P0_PARAM2_RX_EQ(x)     __set(x, 20, 18)
+#define SATA_PHY_P0_PARAM2_RX_EQ_MASK   GENMASK(20, 18)
+
+#define SATA_PHY_P0_PARAM3              0x20C
+#define SATA_PHY_SSC_EN                 0x8
+#define SATA_PHY_P0_PARAM4              0x210
+#define SATA_PHY_REF_SSP_EN             0x2
+#define SATA_PHY_RESET                  0x1
+
+static int qcom_ipq806x_sata_phy_init(struct phy *generic_phy)
+{
+        struct qcom_ipq806x_sata_phy *phy = phy_get_drvdata(generic_phy);
+        u32 reg;
+
+        /* Setting SSC_EN to 1 */
+        reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM3);
+        reg = reg | SATA_PHY_SSC_EN;
+        writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM3);
+
+        reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM0) &
+                        ~(SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3_MASK |
+                          SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN2_MASK |
+                          SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN1_MASK);
+        reg |= SATA_PHY_P0_PARAM0_P0_TX_PREEMPH_GEN3(0xf);
+        writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM0);
+
+        reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM1) &
+                        ~(SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3_MASK |
+                          SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2_MASK |
+                          SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1_MASK);
+        reg |= SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN3(0x55) |
+                SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN2(0x55) |
+                SATA_PHY_P0_PARAM1_P0_TX_AMPLITUDE_GEN1(0x55);
+        writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM1);
+
+        reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM2) &
+                ~SATA_PHY_P0_PARAM2_RX_EQ_MASK;
+        reg |= SATA_PHY_P0_PARAM2_RX_EQ(0x3);
+        writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM2);
+
+        /* Setting PHY_RESET to 1 */
+        reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
+        reg = reg | SATA_PHY_RESET;
+        writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
+
+        /* Setting REF_SSP_EN to 1 */
+        reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
+        reg = reg | SATA_PHY_REF_SSP_EN | SATA_PHY_RESET;
+        writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
+
+        /* make sure all changes complete before we let the PHY out of reset */
+        mb();
+
+        /* sleep for max. 50us more to combine processor wakeups */
+        usleep_range(20, 20 + 50);
+
+        /* Clearing PHY_RESET to 0 */
+        reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
+        reg = reg & ~SATA_PHY_RESET;
+        writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
+
+        return 0;
+}
+
+static int qcom_ipq806x_sata_phy_exit(struct phy *generic_phy)
+{
+        struct qcom_ipq806x_sata_phy *phy = phy_get_drvdata(generic_phy);
+        u32 reg;
+
+        /* Setting PHY_RESET to 1 */
+        reg = readl_relaxed(phy->mmio + SATA_PHY_P0_PARAM4);
+        reg = reg | SATA_PHY_RESET;
+        writel_relaxed(reg, phy->mmio + SATA_PHY_P0_PARAM4);
+
+        return 0;
+}
+
+static struct phy_ops qcom_ipq806x_sata_phy_ops = {
+        .init           = qcom_ipq806x_sata_phy_init,
+        .exit           = qcom_ipq806x_sata_phy_exit,
+        .owner          = THIS_MODULE,
+};
+
+static int qcom_ipq806x_sata_phy_probe(struct platform_device *pdev)
+{
+        struct qcom_ipq806x_sata_phy *phy;
+        struct device *dev = &pdev->dev;
+        struct resource *res;
+        struct phy_provider *phy_provider;
+        struct phy *generic_phy;
+        int ret;
+
+        phy = devm_kzalloc(dev, sizeof(*phy), GFP_KERNEL);
+        if (!phy)
+                return -ENOMEM;
+
+        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+        phy->mmio = devm_ioremap_resource(dev, res);
+        if (IS_ERR(phy->mmio))
+                return PTR_ERR(phy->mmio);
+
+        generic_phy = devm_phy_create(dev, NULL, &qcom_ipq806x_sata_phy_ops,
+                                      NULL);
+        if (IS_ERR(generic_phy)) {
+                dev_err(dev, "%s: failed to create phy\n", __func__);
+                return PTR_ERR(generic_phy);
+        }
+
+        phy->dev = dev;
+        phy_set_drvdata(generic_phy, phy);
+        platform_set_drvdata(pdev, phy);
+
+        phy->cfg_clk = devm_clk_get(dev, "cfg");
+        if (IS_ERR(phy->cfg_clk)) {
+                dev_err(dev, "Failed to get sata cfg clock\n");
+                return PTR_ERR(phy->cfg_clk);
+        }
+
+        ret = clk_prepare_enable(phy->cfg_clk);
+        if (ret)
+                return ret;
+
+        phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+        if (IS_ERR(phy_provider)) {
+                clk_disable_unprepare(phy->cfg_clk);
+                dev_err(dev, "%s: failed to register phy\n", __func__);
+                return PTR_ERR(phy_provider);
+        }
+
+        return 0;
+}
+
+static int qcom_ipq806x_sata_phy_remove(struct platform_device *pdev)
+{
+        struct qcom_ipq806x_sata_phy *phy = platform_get_drvdata(pdev);
+
+        clk_disable_unprepare(phy->cfg_clk);
+
+        return 0;
+}
+
+static const struct of_device_id qcom_ipq806x_sata_phy_of_match[] = {
+        { .compatible = "qcom,ipq806x-sata-phy" },
+        { },
+};
+MODULE_DEVICE_TABLE(of, qcom_ipq806x_sata_phy_of_match);
+
+static struct platform_driver qcom_ipq806x_sata_phy_driver = {
+        .probe  = qcom_ipq806x_sata_phy_probe,
+        .remove = qcom_ipq806x_sata_phy_remove,
+        .driver = {
+                .name   = "qcom-ipq806x-sata-phy",
+                .owner  = THIS_MODULE,
+                .of_match_table = qcom_ipq806x_sata_phy_of_match,
+        }
+};
+module_platform_driver(qcom_ipq806x_sata_phy_driver);
+
+MODULE_DESCRIPTION("QCOM IPQ806x SATA PHY driver");
+MODULE_LICENSE("GPL v2");