drivers/phy/hisilicon/phy-histb-combphy.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * COMBPHY driver for HiSilicon STB SoCs
   4  *
   5  * Copyright (C) 2016-2017 HiSilicon Co., Ltd. http://www.hisilicon.com
   6  *
   7  * Authors: Jianguo Sun <[email protected]>
   8  */
   9
  10 #include <linux/clk.h>
  11 #include <linux/delay.h>
  12 #include <linux/io.h>
  13 #include <linux/kernel.h>
  14 #include <linux/mfd/syscon.h>
  15 #include <linux/module.h>
  16 #include <linux/of_device.h>
  17 #include <linux/phy/phy.h>
  18 #include <linux/regmap.h>
  19 #include <linux/reset.h>
  20 #include <dt-bindings/phy/phy.h>
  21
  22 #define COMBPHY_MODE_PCIE               0
  23 #define COMBPHY_MODE_USB3               1
  24 #define COMBPHY_MODE_SATA               2
  25
  26 #define COMBPHY_CFG_REG                 0x0
  27 #define COMBPHY_BYPASS_CODEC            BIT(31)
  28 #define COMBPHY_TEST_WRITE              BIT(24)
  29 #define COMBPHY_TEST_DATA_SHIFT         20
  30 #define COMBPHY_TEST_DATA_MASK          GENMASK(23, 20)
  31 #define COMBPHY_TEST_ADDR_SHIFT         12
  32 #define COMBPHY_TEST_ADDR_MASK          GENMASK(16, 12)
  33 #define COMBPHY_CLKREF_OUT_OEN          BIT(0)
  34
  35 struct histb_combphy_mode {
  36         int fixed;
  37         int select;
  38         u32 reg;
  39         u32 shift;
  40         u32 mask;
  41 };
  42
  43 struct histb_combphy_priv {
  44         void __iomem *mmio;
  45         struct regmap *syscon;
  46         struct reset_control *por_rst;
  47         struct clk *ref_clk;
  48         struct phy *phy;
  49         struct histb_combphy_mode mode;
  50 };
  51
  52 static void nano_register_write(struct histb_combphy_priv *priv,
  53                                 u32 addr, u32 data)
  54 {
  55         void __iomem *reg = priv->mmio + COMBPHY_CFG_REG;
  56         u32 val;
  57
  58         /* Set up address and data for the write */
  59         val = readl(reg);
  60         val &= ~COMBPHY_TEST_ADDR_MASK;
  61         val |= addr << COMBPHY_TEST_ADDR_SHIFT;
  62         val &= ~COMBPHY_TEST_DATA_MASK;
  63         val |= data << COMBPHY_TEST_DATA_SHIFT;
  64         writel(val, reg);
  65
  66         /* Flip strobe control to trigger the write */
  67         val &= ~COMBPHY_TEST_WRITE;
  68         writel(val, reg);
  69         val |= COMBPHY_TEST_WRITE;
  70         writel(val, reg);
  71 }
  72
  73 static int is_mode_fixed(struct histb_combphy_mode *mode)
  74 {
  75         return (mode->fixed != PHY_NONE) ? true : false;
  76 }
  77
  78 static int histb_combphy_set_mode(struct histb_combphy_priv *priv)
  79 {
  80         struct histb_combphy_mode *mode = &priv->mode;
  81         struct regmap *syscon = priv->syscon;
  82         u32 hw_sel;
  83
  84         if (is_mode_fixed(mode))
  85                 return 0;
  86
  87         switch (mode->select) {
  88         case PHY_TYPE_SATA:
  89                 hw_sel = COMBPHY_MODE_SATA;
  90                 break;
  91         case PHY_TYPE_PCIE:
  92                 hw_sel = COMBPHY_MODE_PCIE;
  93                 break;
  94         case PHY_TYPE_USB3:
  95                 hw_sel = COMBPHY_MODE_USB3;
  96                 break;
  97         default:
  98                 return -EINVAL;
  99         }
 100
 101         return regmap_update_bits(syscon, mode->reg, mode->mask,
 102                                   hw_sel << mode->shift);
 103 }
 104
 105 static int histb_combphy_init(struct phy *phy)
 106 {
 107         struct histb_combphy_priv *priv = phy_get_drvdata(phy);
 108         u32 val;
 109         int ret;
 110
 111         ret = histb_combphy_set_mode(priv);
 112         if (ret)
 113                 return ret;
 114
 115         /* Clear bypass bit to enable encoding/decoding */
 116         val = readl(priv->mmio + COMBPHY_CFG_REG);
 117         val &= ~COMBPHY_BYPASS_CODEC;
 118         writel(val, priv->mmio + COMBPHY_CFG_REG);
 119
 120         ret = clk_prepare_enable(priv->ref_clk);
 121         if (ret)
 122                 return ret;
 123
 124         reset_control_deassert(priv->por_rst);
 125
 126         /* Enable EP clock */
 127         val = readl(priv->mmio + COMBPHY_CFG_REG);
 128         val |= COMBPHY_CLKREF_OUT_OEN;
 129         writel(val, priv->mmio + COMBPHY_CFG_REG);
 130
 131         /* Need to wait for EP clock stable */
 132         mdelay(5);
 133
 134         /* Configure nano phy registers as suggested by vendor */
 135         nano_register_write(priv, 0x1, 0x8);
 136         nano_register_write(priv, 0xc, 0x9);
 137         nano_register_write(priv, 0x1a, 0x4);
 138
 139         return 0;
 140 }
 141
 142 static int histb_combphy_exit(struct phy *phy)
 143 {
 144         struct histb_combphy_priv *priv = phy_get_drvdata(phy);
 145         u32 val;
 146
 147         /* Disable EP clock */
 148         val = readl(priv->mmio + COMBPHY_CFG_REG);
 149         val &= ~COMBPHY_CLKREF_OUT_OEN;
 150         writel(val, priv->mmio + COMBPHY_CFG_REG);
 151
 152         reset_control_assert(priv->por_rst);
 153         clk_disable_unprepare(priv->ref_clk);
 154
 155         return 0;
 156 }
 157
 158 static const struct phy_ops histb_combphy_ops = {
 159         .init = histb_combphy_init,
 160         .exit = histb_combphy_exit,
 161         .owner = THIS_MODULE,
 162 };
 163
 164 static struct phy *histb_combphy_xlate(struct device *dev,
 165                                        struct of_phandle_args *args)
 166 {
 167         struct histb_combphy_priv *priv = dev_get_drvdata(dev);
 168         struct histb_combphy_mode *mode = &priv->mode;
 169
 170         if (args->args_count < 1) {
 171                 dev_err(dev, "invalid number of arguments\n");
 172                 return ERR_PTR(-EINVAL);
 173         }
 174
 175         mode->select = args->args[0];
 176
 177         if (mode->select < PHY_TYPE_SATA || mode->select > PHY_TYPE_USB3) {
 178                 dev_err(dev, "invalid phy mode select argument\n");
 179                 return ERR_PTR(-EINVAL);
 180         }
 181
 182         if (is_mode_fixed(mode) && mode->select != mode->fixed) {
 183                 dev_err(dev, "mode select %d mismatch fixed phy mode %d\n",
 184                         mode->select, mode->fixed);
 185                 return ERR_PTR(-EINVAL);
 186         }
 187
 188         return priv->phy;
 189 }
 190
 191 static int histb_combphy_probe(struct platform_device *pdev)
 192 {
 193         struct phy_provider *phy_provider;
 194         struct device *dev = &pdev->dev;
 195         struct histb_combphy_priv *priv;
 196         struct device_node *np = dev->of_node;
 197         struct histb_combphy_mode *mode;
 198         u32 vals[3];
 199         int ret;
 200
 201         priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
 202         if (!priv)
 203                 return -ENOMEM;
 204
 205         priv->mmio = devm_platform_ioremap_resource(pdev, 0);
 206         if (IS_ERR(priv->mmio)) {
 207                 ret = PTR_ERR(priv->mmio);
 208                 return ret;
 209         }
 210
 211         priv->syscon = syscon_node_to_regmap(np->parent);
 212         if (IS_ERR(priv->syscon)) {
 213                 dev_err(dev, "failed to find peri_ctrl syscon regmap\n");
 214                 return PTR_ERR(priv->syscon);
 215         }
 216
 217         mode = &priv->mode;
 218         mode->fixed = PHY_NONE;
 219
 220         ret = of_property_read_u32(np, "hisilicon,fixed-mode", &mode->fixed);
 221         if (ret == 0)
 222                 dev_dbg(dev, "found fixed phy mode %d\n", mode->fixed);
 223
 224         ret = of_property_read_u32_array(np, "hisilicon,mode-select-bits",
 225                                          vals, ARRAY_SIZE(vals));
 226         if (ret == 0) {
 227                 if (is_mode_fixed(mode)) {
 228                         dev_err(dev, "found select bits for fixed mode phy\n");
 229                         return -EINVAL;
 230                 }
 231
 232                 mode->reg = vals[0];
 233                 mode->shift = vals[1];
 234                 mode->mask = vals[2];
 235                 dev_dbg(dev, "found mode select bits\n");
 236         } else {
 237                 if (!is_mode_fixed(mode)) {
 238                         dev_err(dev, "no valid select bits found for non-fixed phy\n");
 239                         return -ENODEV;
 240                 }
 241         }
 242
 243         priv->ref_clk = devm_clk_get(dev, NULL);
 244         if (IS_ERR(priv->ref_clk)) {
 245                 dev_err(dev, "failed to find ref clock\n");
 246                 return PTR_ERR(priv->ref_clk);
 247         }
 248
 249         priv->por_rst = devm_reset_control_get(dev, NULL);
 250         if (IS_ERR(priv->por_rst)) {
 251                 dev_err(dev, "failed to get poweron reset\n");
 252                 return PTR_ERR(priv->por_rst);
 253         }
 254
 255         priv->phy = devm_phy_create(dev, NULL, &histb_combphy_ops);
 256         if (IS_ERR(priv->phy)) {
 257                 dev_err(dev, "failed to create combphy\n");
 258                 return PTR_ERR(priv->phy);
 259         }
 260
 261         dev_set_drvdata(dev, priv);
 262         phy_set_drvdata(priv->phy, priv);
 263
 264         phy_provider = devm_of_phy_provider_register(dev, histb_combphy_xlate);
 265         return PTR_ERR_OR_ZERO(phy_provider);
 266 }
 267
 268 static const struct of_device_id histb_combphy_of_match[] = {
 269         { .compatible = "hisilicon,hi3798cv200-combphy" },
 270         { },
 271 };
 272 MODULE_DEVICE_TABLE(of, histb_combphy_of_match);
 273
 274 static struct platform_driver histb_combphy_driver = {
 275         .probe  = histb_combphy_probe,
 276         .driver = {
 277                 .name = "combphy",
 278                 .of_match_table = histb_combphy_of_match,
 279         },
 280 };
 281 module_platform_driver(histb_combphy_driver);
 282
 283 MODULE_DESCRIPTION("HiSilicon STB COMBPHY driver");
 284 MODULE_LICENSE("GPL v2");