Add a PCIe PHY driver used by PCIe host controller driver on Qualcomm SoCs like Snapdragon 805. Signed-off-by: Stanimir Varbanov <svarbanov@xxxxxxxxxx> --- drivers/phy/Kconfig | 9 ++ drivers/phy/Makefile | 1 + drivers/phy/phy-qcom-pcie.c | 291 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 301 insertions(+), 0 deletions(-) create mode 100644 drivers/phy/phy-qcom-pcie.c diff --git a/drivers/phy/Kconfig b/drivers/phy/Kconfig index a53bd5b..6cf9065 100644 --- a/drivers/phy/Kconfig +++ b/drivers/phy/Kconfig @@ -257,6 +257,15 @@ 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 + help + Enable support for PCIe phy driver + config PHY_ROCKCHIP_USB tristate "Rockchip USB2 PHY Driver" depends on ARCH_ROCKCHIP && OF diff --git a/drivers/phy/Makefile b/drivers/phy/Makefile index f126251..d80b99b 100644 --- a/drivers/phy/Makefile +++ b/drivers/phy/Makefile @@ -32,6 +32,7 @@ obj-$(CONFIG_PHY_EXYNOS5_USBDRD) += phy-exynos5-usbdrd.o obj-$(CONFIG_PHY_QCOM_APQ8064_SATA) += phy-qcom-apq8064-sata.o obj-$(CONFIG_PHY_ROCKCHIP_USB) += phy-rockchip-usb.o obj-$(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..0ce2fc6 --- /dev/null +++ b/drivers/phy/phy-qcom-pcie.c @@ -0,0 +1,291 @@ +/* + * 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 device *dev; +}; + +struct phy_regs { + u32 reg_offset; + u32 val; +}; + +static const struct phy_regs pcie_phy_pwrup[] = { + { 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 const struct phy_regs pcie_phy_pwrdown[] = { + { PCIE_PHY_SW_RESET, 0x01 }, + { PCIE_PHY_POWER_DOWN_CONTROL, 0x00 }, +}; + +static void qcom_pcie_phy_pwr(struct qcom_pcie_phy *pcie, + const struct phy_regs *regs, int arr_size) +{ + int i; + + for (i = 0; i < arr_size; i++) + writel(regs[i].val, pcie->base + regs[i].reg_offset); +} + +static void qcom_pcie_phy_pwrup(struct qcom_pcie_phy *pcie) +{ + qcom_pcie_phy_pwr(pcie, pcie_phy_pwrup, ARRAY_SIZE(pcie_phy_pwrup)); +} + +static void qcom_pcie_phy_pwrdown(struct qcom_pcie_phy *pcie) +{ + qcom_pcie_phy_pwr(pcie, pcie_phy_pwrdown, ARRAY_SIZE(pcie_phy_pwrdown)); +} + +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 = reset_control_deassert(pcie->res_phy); + if (ret) { + dev_err(dev, "cannot deassert phy reset\n"); + goto fail_vdda_pll; + } + + qcom_pcie_phy_pwrup(pcie); + + ret = clk_set_rate(pcie->clk, ~0); + if (ret) { + dev_err(dev, "cannot set phy clock 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, "cannot power on phy\n"); + ret = -ETIMEDOUT; + goto fail; + } + + return 0; + +fail: + clk_disable_unprepare(pcie->clk); +fail_res: + reset_control_assert(pcie->res_phy); +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); + + clk_disable_unprepare(pcie->clk); + qcom_pcie_phy_pwrdown(pcie); + reset_control_assert(pcie->res_phy); + regulator_disable(pcie->vdda_pll); + + return 0; +} + +static const 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)) + return PTR_ERR(pcie->clk); + + pcie->vdda_pll = devm_regulator_get(dev, "vdda_pll"); + if (IS_ERR(pcie->vdda_pll)) + return PTR_ERR(pcie->vdda_pll); + + pcie->res_phy = devm_reset_control_get(dev, "core"); + if (IS_ERR(pcie->res_phy)) + return PTR_ERR(pcie->res_phy); + + phy = devm_phy_create(dev, NULL, &qcom_pcie_phy_ops); + if (IS_ERR(phy)) { + dev_err(dev, "cannot 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, "cannot register phy provider\n"); + return PTR_ERR(provider); + } + + pcie->dev = dev; + phy_set_drvdata(phy, pcie); + platform_set_drvdata(pdev, pcie); + + 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, + .driver = { + .name = "pcie-phy", + .of_match_table = qcom_pcie_phy_of_match, + } +}; + +module_platform_driver(qcom_pcie_phy_driver); + +MODULE_AUTHOR("Stanimir Varbanov <svarbanov@xxxxxxxxxx>"); +MODULE_DESCRIPTION("Qualcomm PCIe PHY driver"); +MODULE_LICENSE("GPL v2"); +MODULE_ALIAS("platform:pcie-phy"); -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html