drivers/phy/samsung/phy-exynos-pcie.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Samsung Exynos SoC series PCIe PHY driver
   4  *
   5  * Phy provider for PCIe controller on Exynos SoC series
   6  *
   7  * Copyright (C) 2017-2020 Samsung Electronics Co., Ltd.
   8  * Jaehoon Chung <jh80.chung@samsung.com>
   9  */
  10
  11 #include <linux/io.h>
  12 #include <linux/mfd/syscon.h>
  13 #include <linux/of_platform.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/phy/phy.h>
  16 #include <linux/regmap.h>
  17
  18 #define PCIE_PHY_OFFSET(x)              ((x) * 0x4)
  19
  20 /* Sysreg FSYS register offsets and bits for Exynos5433 */
  21 #define PCIE_EXYNOS5433_PHY_MAC_RESET           0x0208
  22 #define PCIE_MAC_RESET_MASK                     0xFF
  23 #define PCIE_MAC_RESET                          BIT(4)
  24 #define PCIE_EXYNOS5433_PHY_L1SUB_CM_CON        0x1010
  25 #define PCIE_REFCLK_GATING_EN                   BIT(0)
  26 #define PCIE_EXYNOS5433_PHY_COMMON_RESET        0x1020
  27 #define PCIE_PHY_RESET                          BIT(0)
  28 #define PCIE_EXYNOS5433_PHY_GLOBAL_RESET        0x1040
  29 #define PCIE_GLOBAL_RESET                       BIT(0)
  30 #define PCIE_REFCLK                             BIT(1)
  31 #define PCIE_REFCLK_MASK                        0x16
  32 #define PCIE_APP_REQ_EXIT_L1_MODE               BIT(5)
  33
  34 /* PMU PCIE PHY isolation control */
  35 #define EXYNOS5433_PMU_PCIE_PHY_OFFSET          0x730
  36
  37 /* For Exynos pcie phy */
  38 struct exynos_pcie_phy {
  39         void __iomem *base;
  40         struct regmap *pmureg;
  41         struct regmap *fsysreg;
  42 };
  43
  44 static void exynos_pcie_phy_writel(void __iomem *base, u32 val, u32 offset)
  45 {
  46         writel(val, base + offset);
  47 }
  48
  49 /* Exynos5433 specific functions */
  50 static int exynos5433_pcie_phy_init(struct phy *phy)
  51 {
  52         struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
  53
  54         regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_COMMON_RESET,
  55                            PCIE_PHY_RESET, 1);
  56         regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_MAC_RESET,
  57                            PCIE_MAC_RESET, 0);
  58
  59         /* PHY refclk 24MHz */
  60         regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
  61                            PCIE_REFCLK_MASK, PCIE_REFCLK);
  62         regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
  63                            PCIE_GLOBAL_RESET, 0);
  64
  65
  66         exynos_pcie_phy_writel(ep->base, 0x11, PCIE_PHY_OFFSET(0x3));
  67
  68         /* band gap reference on */
  69         exynos_pcie_phy_writel(ep->base, 0, PCIE_PHY_OFFSET(0x20));
  70         exynos_pcie_phy_writel(ep->base, 0, PCIE_PHY_OFFSET(0x4b));
  71
  72         /* jitter tuning */
  73         exynos_pcie_phy_writel(ep->base, 0x34, PCIE_PHY_OFFSET(0x4));
  74         exynos_pcie_phy_writel(ep->base, 0x02, PCIE_PHY_OFFSET(0x7));
  75         exynos_pcie_phy_writel(ep->base, 0x41, PCIE_PHY_OFFSET(0x21));
  76         exynos_pcie_phy_writel(ep->base, 0x7F, PCIE_PHY_OFFSET(0x14));
  77         exynos_pcie_phy_writel(ep->base, 0xC0, PCIE_PHY_OFFSET(0x15));
  78         exynos_pcie_phy_writel(ep->base, 0x61, PCIE_PHY_OFFSET(0x36));
  79
  80         /* D0 uninit.. */
  81         exynos_pcie_phy_writel(ep->base, 0x44, PCIE_PHY_OFFSET(0x3D));
  82
  83         /* 24MHz */
  84         exynos_pcie_phy_writel(ep->base, 0x94, PCIE_PHY_OFFSET(0x8));
  85         exynos_pcie_phy_writel(ep->base, 0xA7, PCIE_PHY_OFFSET(0x9));
  86         exynos_pcie_phy_writel(ep->base, 0x93, PCIE_PHY_OFFSET(0xA));
  87         exynos_pcie_phy_writel(ep->base, 0x6B, PCIE_PHY_OFFSET(0xC));
  88         exynos_pcie_phy_writel(ep->base, 0xA5, PCIE_PHY_OFFSET(0xF));
  89         exynos_pcie_phy_writel(ep->base, 0x34, PCIE_PHY_OFFSET(0x16));
  90         exynos_pcie_phy_writel(ep->base, 0xA3, PCIE_PHY_OFFSET(0x17));
  91         exynos_pcie_phy_writel(ep->base, 0xA7, PCIE_PHY_OFFSET(0x1A));
  92         exynos_pcie_phy_writel(ep->base, 0x71, PCIE_PHY_OFFSET(0x23));
  93         exynos_pcie_phy_writel(ep->base, 0x4C, PCIE_PHY_OFFSET(0x24));
  94
  95         exynos_pcie_phy_writel(ep->base, 0x0E, PCIE_PHY_OFFSET(0x26));
  96         exynos_pcie_phy_writel(ep->base, 0x14, PCIE_PHY_OFFSET(0x7));
  97         exynos_pcie_phy_writel(ep->base, 0x48, PCIE_PHY_OFFSET(0x43));
  98         exynos_pcie_phy_writel(ep->base, 0x44, PCIE_PHY_OFFSET(0x44));
  99         exynos_pcie_phy_writel(ep->base, 0x03, PCIE_PHY_OFFSET(0x45));
 100         exynos_pcie_phy_writel(ep->base, 0xA7, PCIE_PHY_OFFSET(0x48));
 101         exynos_pcie_phy_writel(ep->base, 0x13, PCIE_PHY_OFFSET(0x54));
 102         exynos_pcie_phy_writel(ep->base, 0x04, PCIE_PHY_OFFSET(0x31));
 103         exynos_pcie_phy_writel(ep->base, 0, PCIE_PHY_OFFSET(0x32));
 104
 105         regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_COMMON_RESET,
 106                            PCIE_PHY_RESET, 0);
 107         regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_MAC_RESET,
 108                            PCIE_MAC_RESET_MASK, PCIE_MAC_RESET);
 109         return 0;
 110 }
 111
 112 static int exynos5433_pcie_phy_power_on(struct phy *phy)
 113 {
 114         struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
 115
 116         regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
 117                            BIT(0), 1);
 118         regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_GLOBAL_RESET,
 119                            PCIE_APP_REQ_EXIT_L1_MODE, 0);
 120         regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
 121                            PCIE_REFCLK_GATING_EN, 0);
 122         return 0;
 123 }
 124
 125 static int exynos5433_pcie_phy_power_off(struct phy *phy)
 126 {
 127         struct exynos_pcie_phy *ep = phy_get_drvdata(phy);
 128
 129         regmap_update_bits(ep->fsysreg, PCIE_EXYNOS5433_PHY_L1SUB_CM_CON,
 130                            PCIE_REFCLK_GATING_EN, PCIE_REFCLK_GATING_EN);
 131         regmap_update_bits(ep->pmureg, EXYNOS5433_PMU_PCIE_PHY_OFFSET,
 132                            BIT(0), 0);
 133         return 0;
 134 }
 135
 136 static const struct phy_ops exynos5433_phy_ops = {
 137         .init           = exynos5433_pcie_phy_init,
 138         .power_on       = exynos5433_pcie_phy_power_on,
 139         .power_off      = exynos5433_pcie_phy_power_off,
 140         .owner          = THIS_MODULE,
 141 };
 142
 143 static const struct of_device_id exynos_pcie_phy_match[] = {
 144         {
 145                 .compatible = "samsung,exynos5433-pcie-phy",
 146         },
 147         {},
 148 };
 149
 150 static int exynos_pcie_phy_probe(struct platform_device *pdev)
 151 {
 152         struct device *dev = &pdev->dev;
 153         struct exynos_pcie_phy *exynos_phy;
 154         struct phy *generic_phy;
 155         struct phy_provider *phy_provider;
 156
 157         exynos_phy = devm_kzalloc(dev, sizeof(*exynos_phy), GFP_KERNEL);
 158         if (!exynos_phy)
 159                 return -ENOMEM;
 160
 161         exynos_phy->base = devm_platform_ioremap_resource(pdev, 0);
 162         if (IS_ERR(exynos_phy->base))
 163                 return PTR_ERR(exynos_phy->base);
 164
 165         exynos_phy->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node,
 166                                                         "samsung,pmu-syscon");
 167         if (IS_ERR(exynos_phy->pmureg)) {
 168                 dev_err(&pdev->dev, "PMU regmap lookup failed.\n");
 169                 return PTR_ERR(exynos_phy->pmureg);
 170         }
 171
 172         exynos_phy->fsysreg = syscon_regmap_lookup_by_phandle(dev->of_node,
 173                                                          "samsung,fsys-sysreg");
 174         if (IS_ERR(exynos_phy->fsysreg)) {
 175                 dev_err(&pdev->dev, "FSYS sysreg regmap lookup failed.\n");
 176                 return PTR_ERR(exynos_phy->fsysreg);
 177         }
 178
 179         generic_phy = devm_phy_create(dev, dev->of_node, &exynos5433_phy_ops);
 180         if (IS_ERR(generic_phy)) {
 181                 dev_err(dev, "failed to create PHY\n");
 182                 return PTR_ERR(generic_phy);
 183         }
 184
 185         phy_set_drvdata(generic_phy, exynos_phy);
 186         phy_provider = devm_of_phy_provider_register(dev, of_phy_simple_xlate);
 187
 188         return PTR_ERR_OR_ZERO(phy_provider);
 189 }
 190
 191 static struct platform_driver exynos_pcie_phy_driver = {
 192         .probe  = exynos_pcie_phy_probe,
 193         .driver = {
 194                 .of_match_table = exynos_pcie_phy_match,
 195                 .name           = "exynos_pcie_phy",
 196                 .suppress_bind_attrs = true,
 197         }
 198 };
 199 builtin_platform_driver(exynos_pcie_phy_driver);