Add a PCIe PHY driver used by PCIe host controller driver
on Qualcomm SoCs like Snapdragon 805.

Signed-off-by: Stanimir Varbanov <svarba...@mm-sol.com>
---
 drivers/phy/Kconfig         |    7 +
 drivers/phy/Makefile        |    1 +
 drivers/phy/phy-qcom-pcie.c |  311 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 319 insertions(+), 0 deletions(-)
 create mode 100644 drivers/phy/phy-qcom-pcie.c

diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig
index 2a436e6..135bdcc 100644
--- a/drivers/phy/Kconfig
+++ b/drivers/phy/Kconfig
@@ -218,6 +218,13 @@ config PHY_QCOM_IPQ806X_SATA
        depends on OF
        select GENERIC_PHY
 
+config PHY_QCOM_PCIE
+       tristate "Qualcomm PCIe SerDes/PHY driver"
+       depends on ARCH_QCOM
+       depends on HAS_IOMEM
+       depends on OF
+       select GENERIC_PHY
+
 config PHY_ST_SPEAR1310_MIPHY
        tristate "ST SPEAR1310-MIPHY driver"
        select GENERIC_PHY
diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile
index c4590fc..e7662fb 100644
--- a/drivers/phy/Makefile
+++ b/drivers/phy/Makefile
@@ -26,6 +26,7 @@ phy-exynos-usb2-$(CONFIG_PHY_S5PV210_USB2)    += 
phy-s5pv210-usb2.o
 obj-$(CONFIG_PHY_EXYNOS5_USBDRD)       += phy-exynos5-usbdrd.o
 obj-$(CONFIG_PHY_QCOM_APQ8064_SATA)    += phy-qcom-apq8064-sata.o
 obj-$(CONFIG_PHY_QCOM_IPQ806X_SATA)    += phy-qcom-ipq806x-sata.o
+obj-$(CONFIG_PHY_QCOM_PCIE)            += phy-qcom-pcie.o
 obj-$(CONFIG_PHY_ST_SPEAR1310_MIPHY)   += phy-spear1310-miphy.o
 obj-$(CONFIG_PHY_ST_SPEAR1340_MIPHY)   += phy-spear1340-miphy.o
 obj-$(CONFIG_PHY_XGENE)                        += phy-xgene.o
diff --git a/drivers/phy/phy-qcom-pcie.c b/drivers/phy/phy-qcom-pcie.c
new file mode 100644
index 0000000..3db348a
--- /dev/null
+++ b/drivers/phy/phy-qcom-pcie.c
@@ -0,0 +1,311 @@
+/*
+ * 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/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/io.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/phy/phy.h>
+#include <linux/platform_device.h>
+#include <linux/reset.h>
+
+#define QSERDES_COM_PLL_CP_SETI                        0x024
+#define QSERDES_COM_PLL_IP_SETP                        0x028
+#define QSERDES_COM_PLL_CP_SETP                        0x02c
+#define QSERDES_COM_SYSCLK_EN_SEL              0x038
+#define QSERDES_COM_RESETSM_CNTRL              0x040
+#define QSERDES_COM_PLLLOCK_CMP1               0x044
+#define QSERDES_COM_PLLLOCK_CMP2               0x048
+#define QSERDES_COM_PLLLOCK_CMP_EN             0x050
+#define QSERDES_COM_DEC_START1                 0x064
+#define QSERDES_COM_DIV_FRAC_START1            0x098
+#define QSERDES_COM_DIV_FRAC_START2            0x09c
+#define QSERDES_COM_DIV_FRAC_START3            0x0a0
+#define QSERDES_COM_DEC_START2                 0x0a4
+#define QSERDES_COM_PLL_RXTXEPCLK_EN           0x0a8
+#define QSERDES_COM_PLL_CRCTRL                 0x0ac
+
+#define QSERDES_RX_CDR_CONTROL                 0x400
+#define QSERDES_RX_CDR_CONTROL2                        0x410
+#define QSERDES_RX_RX_TERM_HIGHZ_CM_AC_COUPLE  0x42c
+#define QSERDES_RX_RX_EQ_GAIN12                        0x430
+
+#define PCIE_PHY_SW_RESET                      0x600
+#define PCIE_PHY_POWER_DOWN_CONTROL            0x604
+#define PCIE_PHY_START                         0x608
+#define PCIE_PHY_ENDPOINT_REFCLK_DRIVE         0x648
+#define PCIE_PHY_POWER_STATE_CONFIG1           0x650
+#define PCIE_PHY_POWER_STATE_CONFIG2           0x654
+#define PCIE_PHY_PWRUP_RESET_DLY_TIME_SYSCLK   0x678
+#define PCIE_PHY_PWRUP_RESET_DLY_TIME_AUXCLK   0x67c
+#define PCIE_PHY_PCS_STATUS                    0x6c8
+
+#define PHY_DELAY_MIN_US                       995
+#define PHY_DELAY_MAX_US                       1005
+#define PHY_RETRIES_COUNT                      10
+
+#define PIPE_CLK_DELAY_MIN_US                  5000
+#define PIPE_CLK_DELAY_MAX_US                  5100
+#define PIPE_CLK_RETRIES_COUNT                 10
+
+struct qcom_pcie_phy {
+       void __iomem *base;
+       struct clk *clk;
+       struct reset_control *res_phy;
+       struct regulator *vdda_pll;
+       struct regulator *vdda;
+       struct device *dev;
+};
+
+struct phy_regs {
+       u32 reg_offset;
+       u32 val;
+};
+
+static const struct phy_regs pcie_phy_regs[] = {
+       { PCIE_PHY_POWER_DOWN_CONTROL,                  0x03 },
+       { QSERDES_COM_SYSCLK_EN_SEL,                    0x08 },
+       { QSERDES_COM_DEC_START1,                       0x82 },
+       { QSERDES_COM_DEC_START2,                       0x03 },
+       { QSERDES_COM_DIV_FRAC_START1,                  0xd5 },
+       { QSERDES_COM_DIV_FRAC_START2,                  0xaa },
+       { QSERDES_COM_DIV_FRAC_START3,                  0x13 },
+       { QSERDES_COM_PLLLOCK_CMP_EN,                   0x01 },
+       { QSERDES_COM_PLLLOCK_CMP1,                     0x2b },
+       { QSERDES_COM_PLLLOCK_CMP2,                     0x68 },
+       { QSERDES_COM_PLL_CRCTRL,                       0xff },
+       { QSERDES_COM_PLL_CP_SETI,                      0x3f },
+       { QSERDES_COM_PLL_IP_SETP,                      0x07 },
+       { QSERDES_COM_PLL_CP_SETP,                      0x03 },
+       { QSERDES_RX_CDR_CONTROL,                       0xf3 },
+       { QSERDES_RX_CDR_CONTROL2,                      0x6b },
+       { QSERDES_COM_RESETSM_CNTRL,                    0x10 },
+       { QSERDES_RX_RX_TERM_HIGHZ_CM_AC_COUPLE,        0x87 },
+       { QSERDES_RX_RX_EQ_GAIN12,                      0x54 },
+       { PCIE_PHY_POWER_STATE_CONFIG1,                 0xa3 },
+       { PCIE_PHY_POWER_STATE_CONFIG2,                 0xcb },
+       { QSERDES_COM_PLL_RXTXEPCLK_EN,                 0x10 },
+       { PCIE_PHY_ENDPOINT_REFCLK_DRIVE,               0x10 },
+       { PCIE_PHY_SW_RESET,                            0x00 },
+       { PCIE_PHY_START,                               0x03 },
+};
+
+static void qcom_pcie_phy_init(struct qcom_pcie_phy *pcie)
+{
+       const struct phy_regs *regs = pcie_phy_regs;
+       int i;
+
+       for (i = 0; i < ARRAY_SIZE(pcie_phy_regs); i++)
+               writel(regs[i].val, pcie->base + regs[i].reg_offset);
+}
+
+static bool qcom_pcie_phy_is_ready(struct qcom_pcie_phy *pcie)
+{
+       u32 val = readl(pcie->base + PCIE_PHY_PCS_STATUS);
+
+       return val & BIT(6) ? false : true;
+}
+
+static int qcom_pcie_phy_power_on(struct phy *phy)
+{
+       struct qcom_pcie_phy *pcie = phy_get_drvdata(phy);
+       struct device *dev = pcie->dev;
+       int ret, retries;
+
+       ret = regulator_enable(pcie->vdda_pll);
+       if (ret) {
+               dev_err(dev, "cannot enable vdda_pll regulator\n");
+               return ret;
+       }
+
+       ret = regulator_enable(pcie->vdda);
+       if (ret) {
+               dev_err(dev, "cannot enable vdda regulator\n");
+               goto fail_vdda_pll;
+       }
+
+       ret = reset_control_deassert(pcie->res_phy);
+       if (ret) {
+               dev_err(dev, "cannot deassert phy reset\n");
+               goto fail_vdda;
+       }
+
+       qcom_pcie_phy_init(pcie);
+
+       usleep_range(PHY_DELAY_MIN_US, PHY_DELAY_MAX_US);
+
+       ret = clk_set_rate(pcie->clk, ~0);
+       if (ret) {
+               dev_err(dev, "cannot set pipe clk rate\n");
+               goto fail_res;
+       }
+
+       /*
+        * setting pipe rate takes time, try arbitrary delay before enabling
+        * the clock
+        */
+       retries = PIPE_CLK_RETRIES_COUNT;
+       do {
+               usleep_range(PIPE_CLK_DELAY_MIN_US, PIPE_CLK_DELAY_MAX_US);
+
+               ret = clk_prepare_enable(pcie->clk);
+               if (!ret)
+                       break;
+       } while (retries--);
+
+       if (retries < 0) {
+               dev_err(dev, "cannot enable phy clock\n");
+               goto fail_res;
+       }
+
+       retries = PHY_RETRIES_COUNT;
+       do {
+               ret = qcom_pcie_phy_is_ready(pcie);
+               if (ret)
+                       break;
+               usleep_range(PHY_DELAY_MIN_US, PHY_DELAY_MAX_US);
+       } while (retries--);
+
+       if (retries < 0) {
+               dev_err(dev, "phy failed to come up\n");
+               ret = -ETIMEDOUT;
+               goto fail;
+       }
+
+       return 0;
+
+fail:
+       clk_disable_unprepare(pcie->clk);
+fail_res:
+       reset_control_assert(pcie->res_phy);
+fail_vdda:
+       regulator_disable(pcie->vdda);
+fail_vdda_pll:
+       regulator_disable(pcie->vdda_pll);
+
+       return ret;
+}
+
+static int qcom_pcie_phy_power_off(struct phy *phy)
+{
+       struct qcom_pcie_phy *pcie = phy_get_drvdata(phy);
+
+       writel(1, pcie->base + PCIE_PHY_SW_RESET);
+       writel(0, pcie->base + PCIE_PHY_POWER_DOWN_CONTROL);
+
+       reset_control_assert(pcie->res_phy);
+       clk_disable_unprepare(pcie->clk);
+       regulator_disable(pcie->vdda);
+       regulator_disable(pcie->vdda_pll);
+
+       return 0;
+}
+
+static struct phy_ops qcom_pcie_phy_ops = {
+       .power_on = qcom_pcie_phy_power_on,
+       .power_off = qcom_pcie_phy_power_off,
+       .owner = THIS_MODULE,
+};
+
+static int qcom_pcie_phy_probe(struct platform_device *pdev)
+{
+       struct device *dev = &pdev->dev;
+       struct phy_provider *provider;
+       struct qcom_pcie_phy *pcie;
+       struct resource *res;
+       struct phy *phy;
+
+       pcie = devm_kzalloc(dev, sizeof(*pcie), GFP_KERNEL);
+       if (!pcie)
+               return -ENOMEM;
+
+       res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       pcie->base = devm_ioremap_resource(dev, res);
+       if (IS_ERR(pcie->base))
+               return PTR_ERR(pcie->base);
+
+       pcie->clk = devm_clk_get(dev, "core");
+       if (IS_ERR(pcie->clk)) {
+               dev_err(dev, "failed to get pcie phy clock\n");
+               return PTR_ERR(pcie->clk);
+       }
+
+       pcie->vdda = devm_regulator_get(dev, "vdda");
+       if (IS_ERR(pcie->vdda)) {
+               dev_err(dev, "failed to get vdda regulator\n");
+               return PTR_ERR(pcie->vdda);
+       }
+
+       pcie->vdda_pll = devm_regulator_get(dev, "vdda_pll");
+       if (IS_ERR(pcie->vdda_pll)) {
+               dev_err(dev, "failed to get vdda_pll regulator\n");
+               return PTR_ERR(pcie->vdda_pll);
+       }
+
+       pcie->res_phy = devm_reset_control_get(dev, "phy");
+       if (IS_ERR(pcie->res_phy)) {
+               dev_err(dev, "cannot get phy reset controller");
+               return PTR_ERR(pcie->res_phy);
+       }
+
+       phy = devm_phy_create(dev, NULL, &qcom_pcie_phy_ops, NULL);
+       if (IS_ERR(phy)) {
+               dev_err(dev, "failed to create phy\n");
+               return PTR_ERR(phy);
+       }
+
+       provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
+       if (IS_ERR(provider)) {
+               dev_err(dev, "failed to register phy provider\n");
+               return PTR_ERR(provider);
+       }
+
+       pcie->dev = dev;
+       phy_set_drvdata(phy, pcie);
+       platform_set_drvdata(pdev, pcie);
+
+       return 0;
+}
+
+static int qcom_pcie_phy_remove(struct platform_device *pdev)
+{
+       struct qcom_pcie_phy *pcie = platform_get_drvdata(pdev);
+
+       clk_disable_unprepare(pcie->clk);
+
+       return 0;
+}
+
+static const struct of_device_id qcom_pcie_phy_of_match[] = {
+       { .compatible = "qcom,pcie-phy" },
+       { },
+};
+MODULE_DEVICE_TABLE(of, qcom_pcie_phy_of_match);
+
+static struct platform_driver qcom_pcie_phy_driver = {
+       .probe = qcom_pcie_phy_probe,
+       .remove = qcom_pcie_phy_remove,
+       .driver = {
+               .name = "pcie-phy",
+               .of_match_table = qcom_pcie_phy_of_match,
+       }
+};
+module_platform_driver(qcom_pcie_phy_driver);
+
+MODULE_AUTHOR("Stanimir Varbanov <svarba...@mm-sol.com>");
+MODULE_DESCRIPTION("QCOM PCIe PHY driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:pcie-phy");
-- 
1.7.0.4

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