drivers/net/ethernet/arc/emac_rockchip.c

   1 /**
   2  * emac-rockchip.c - Rockchip EMAC specific glue layer
   3  *
   4  * Copyright (C) 2014 Romain Perier <romain.perier@gmail.com>
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  */
  16
  17 #include <linux/etherdevice.h>
  18 #include <linux/mfd/syscon.h>
  19 #include <linux/module.h>
  20 #include <linux/of_net.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/regmap.h>
  23 #include <linux/regulator/consumer.h>
  24
  25 #include "emac.h"
  26
  27 #define DRV_NAME        "rockchip_emac"
  28 #define DRV_VERSION     "1.1"
  29
  30 struct emac_rockchip_soc_data {
  31         unsigned int grf_offset;
  32         unsigned int grf_mode_offset;
  33         unsigned int grf_speed_offset;
  34         bool need_div_macclk;
  35 };
  36
  37 struct rockchip_priv_data {
  38         struct arc_emac_priv emac;
  39         struct regmap *grf;
  40         const struct emac_rockchip_soc_data *soc_data;
  41         struct regulator *regulator;
  42         struct clk *refclk;
  43         struct clk *macclk;
  44 };
  45
  46 static void emac_rockchip_set_mac_speed(void *priv, unsigned int speed)
  47 {
  48         struct rockchip_priv_data *emac = priv;
  49         u32 speed_offset = emac->soc_data->grf_speed_offset;
  50         u32 data;
  51         int err = 0;
  52
  53         switch (speed) {
  54         case 10:
  55                 data = (1 << (speed_offset + 16)) | (0 << speed_offset);
  56                 break;
  57         case 100:
  58                 data = (1 << (speed_offset + 16)) | (1 << speed_offset);
  59                 break;
  60         default:
  61                 pr_err("speed %u not supported\n", speed);
  62                 return;
  63         }
  64
  65         err = regmap_write(emac->grf, emac->soc_data->grf_offset, data);
  66         if (err)
  67                 pr_err("unable to apply speed %u to grf (%d)\n", speed, err);
  68 }
  69
  70 static const struct emac_rockchip_soc_data emac_rk3036_emac_data = {
  71         .grf_offset = 0x140,   .grf_mode_offset = 8,
  72         .grf_speed_offset = 9, .need_div_macclk = 1,
  73 };
  74
  75 static const struct emac_rockchip_soc_data emac_rk3066_emac_data = {
  76         .grf_offset = 0x154,   .grf_mode_offset = 0,
  77         .grf_speed_offset = 1, .need_div_macclk = 0,
  78 };
  79
  80 static const struct emac_rockchip_soc_data emac_rk3188_emac_data = {
  81         .grf_offset = 0x0a4,   .grf_mode_offset = 0,
  82         .grf_speed_offset = 1, .need_div_macclk = 0,
  83 };
  84
  85 static const struct of_device_id emac_rockchip_dt_ids[] = {
  86         {
  87                 .compatible = "rockchip,rk3036-emac",
  88                 .data = &emac_rk3036_emac_data,
  89         },
  90         {
  91                 .compatible = "rockchip,rk3066-emac",
  92                 .data = &emac_rk3066_emac_data,
  93         },
  94         {
  95                 .compatible = "rockchip,rk3188-emac",
  96                 .data = &emac_rk3188_emac_data,
  97         },
  98         { /* Sentinel */ }
  99 };
 100
 101 MODULE_DEVICE_TABLE(of, emac_rockchip_dt_ids);
 102
 103 static int emac_rockchip_probe(struct platform_device *pdev)
 104 {
 105         struct device *dev = &pdev->dev;
 106         struct net_device *ndev;
 107         struct rockchip_priv_data *priv;
 108         const struct of_device_id *match;
 109         u32 data;
 110         int err, interface;
 111
 112         if (!pdev->dev.of_node)
 113                 return -ENODEV;
 114
 115         ndev = alloc_etherdev(sizeof(struct rockchip_priv_data));
 116         if (!ndev)
 117                 return -ENOMEM;
 118         platform_set_drvdata(pdev, ndev);
 119         SET_NETDEV_DEV(ndev, dev);
 120
 121         priv = netdev_priv(ndev);
 122         priv->emac.drv_name = DRV_NAME;
 123         priv->emac.drv_version = DRV_VERSION;
 124         priv->emac.set_mac_speed = emac_rockchip_set_mac_speed;
 125
 126         interface = of_get_phy_mode(dev->of_node);
 127
 128         /* RK3036/RK3066/RK3188 SoCs only support RMII */
 129         if (interface != PHY_INTERFACE_MODE_RMII) {
 130                 dev_err(dev, "unsupported phy interface mode %d\n", interface);
 131                 err = -ENOTSUPP;
 132                 goto out_netdev;
 133         }
 134
 135         priv->grf = syscon_regmap_lookup_by_phandle(dev->of_node,
 136                                                     "rockchip,grf");
 137         if (IS_ERR(priv->grf)) {
 138                 dev_err(dev, "failed to retrieve global register file (%ld)\n",
 139                         PTR_ERR(priv->grf));
 140                 err = PTR_ERR(priv->grf);
 141                 goto out_netdev;
 142         }
 143
 144         match = of_match_node(emac_rockchip_dt_ids, dev->of_node);
 145         priv->soc_data = match->data;
 146
 147         priv->emac.clk = devm_clk_get(dev, "hclk");
 148         if (IS_ERR(priv->emac.clk)) {
 149                 dev_err(dev, "failed to retrieve host clock (%ld)\n",
 150                         PTR_ERR(priv->emac.clk));
 151                 err = PTR_ERR(priv->emac.clk);
 152                 goto out_netdev;
 153         }
 154
 155         priv->refclk = devm_clk_get(dev, "macref");
 156         if (IS_ERR(priv->refclk)) {
 157                 dev_err(dev, "failed to retrieve reference clock (%ld)\n",
 158                         PTR_ERR(priv->refclk));
 159                 err = PTR_ERR(priv->refclk);
 160                 goto out_netdev;
 161         }
 162
 163         err = clk_prepare_enable(priv->refclk);
 164         if (err) {
 165                 dev_err(dev, "failed to enable reference clock (%d)\n", err);
 166                 goto out_netdev;
 167         }
 168
 169         /* Optional regulator for PHY */
 170         priv->regulator = devm_regulator_get_optional(dev, "phy");
 171         if (IS_ERR(priv->regulator)) {
 172                 if (PTR_ERR(priv->regulator) == -EPROBE_DEFER) {
 173                         err = -EPROBE_DEFER;
 174                         goto out_clk_disable;
 175                 }
 176                 dev_err(dev, "no regulator found\n");
 177                 priv->regulator = NULL;
 178         }
 179
 180         if (priv->regulator) {
 181                 err = regulator_enable(priv->regulator);
 182                 if (err) {
 183                         dev_err(dev, "failed to enable phy-supply (%d)\n", err);
 184                         goto out_clk_disable;
 185                 }
 186         }
 187
 188         /* Set speed 100M */
 189         data = (1 << (priv->soc_data->grf_speed_offset + 16)) |
 190                (1 << priv->soc_data->grf_speed_offset);
 191         /* Set RMII mode */
 192         data |= (1 << (priv->soc_data->grf_mode_offset + 16)) |
 193                 (0 << priv->soc_data->grf_mode_offset);
 194
 195         err = regmap_write(priv->grf, priv->soc_data->grf_offset, data);
 196         if (err) {
 197                 dev_err(dev, "unable to apply initial settings to grf (%d)\n",
 198                         err);
 199                 goto out_regulator_disable;
 200         }
 201
 202         /* RMII interface needs always a rate of 50MHz */
 203         err = clk_set_rate(priv->refclk, 50000000);
 204         if (err)
 205                 dev_err(dev,
 206                         "failed to change reference clock rate (%d)\n", err);
 207
 208         if (priv->soc_data->need_div_macclk) {
 209                 priv->macclk = devm_clk_get(dev, "macclk");
 210                 if (IS_ERR(priv->macclk)) {
 211                         dev_err(dev, "failed to retrieve mac clock (%ld)\n",
 212                                 PTR_ERR(priv->macclk));
 213                         err = PTR_ERR(priv->macclk);
 214                         goto out_regulator_disable;
 215                 }
 216
 217                 err = clk_prepare_enable(priv->macclk);
 218                 if (err) {
 219                         dev_err(dev, "failed to enable mac clock (%d)\n", err);
 220                         goto out_regulator_disable;
 221                 }
 222
 223                 /* RMII TX/RX needs always a rate of 25MHz */
 224                 err = clk_set_rate(priv->macclk, 25000000);
 225                 if (err) {
 226                         dev_err(dev,
 227                                 "failed to change mac clock rate (%d)\n", err);
 228                         goto out_clk_disable_macclk;
 229                 }
 230         }
 231
 232         err = arc_emac_probe(ndev, interface);
 233         if (err) {
 234                 dev_err(dev, "failed to probe arc emac (%d)\n", err);
 235                 goto out_regulator_disable;
 236         }
 237
 238         return 0;
 239 out_clk_disable_macclk:
 240         clk_disable_unprepare(priv->macclk);
 241 out_regulator_disable:
 242         if (priv->regulator)
 243                 regulator_disable(priv->regulator);
 244 out_clk_disable:
 245         clk_disable_unprepare(priv->refclk);
 246 out_netdev:
 247         free_netdev(ndev);
 248         return err;
 249 }
 250
 251 static int emac_rockchip_remove(struct platform_device *pdev)
 252 {
 253         struct net_device *ndev = platform_get_drvdata(pdev);
 254         struct rockchip_priv_data *priv = netdev_priv(ndev);
 255         int err;
 256
 257         err = arc_emac_remove(ndev);
 258
 259         clk_disable_unprepare(priv->refclk);
 260
 261         if (priv->regulator)
 262                 regulator_disable(priv->regulator);
 263
 264         if (priv->soc_data->need_div_macclk)
 265                 clk_disable_unprepare(priv->macclk);
 266
 267         free_netdev(ndev);
 268         return err;
 269 }
 270
 271 static struct platform_driver emac_rockchip_driver = {
 272         .probe = emac_rockchip_probe,
 273         .remove = emac_rockchip_remove,
 274         .driver = {
 275                 .name = DRV_NAME,
 276                 .of_match_table  = emac_rockchip_dt_ids,
 277         },
 278 };
 279
 280 module_platform_driver(emac_rockchip_driver);
 281
 282 MODULE_AUTHOR("Romain Perier <romain.perier@gmail.com>");
 283 MODULE_DESCRIPTION("Rockchip EMAC platform driver");
 284 MODULE_LICENSE("GPL");