drivers/net/ethernet/stmicro/stmmac/dwmac-oxnas.c

   1 /*
   2  * Oxford Semiconductor OXNAS DWMAC glue layer
   3  *
   4  * Copyright (C) 2016 Neil Armstrong <narmstrong@baylibre.com>
   5  * Copyright (C) 2014 Daniel Golle <daniel@makrotopia.org>
   6  * Copyright (C) 2013 Ma Haijun <mahaijuns@gmail.com>
   7  * Copyright (C) 2012 John Crispin <blogic@openwrt.org>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program. If not, see <http://www.gnu.org/licenses/>.
  15  */
  16
  17 #include <linux/device.h>
  18 #include <linux/io.h>
  19 #include <linux/module.h>
  20 #include <linux/of.h>
  21 #include <linux/platform_device.h>
  22 #include <linux/regmap.h>
  23 #include <linux/mfd/syscon.h>
  24 #include <linux/stmmac.h>
  25
  26 #include "stmmac_platform.h"
  27
  28 /* System Control regmap offsets */
  29 #define OXNAS_DWMAC_CTRL_REGOFFSET      0x78
  30 #define OXNAS_DWMAC_DELAY_REGOFFSET     0x100
  31
  32 /* Control Register */
  33 #define DWMAC_CKEN_RX_IN        14
  34 #define DWMAC_CKEN_RXN_OUT      13
  35 #define DWMAC_CKEN_RX_OUT       12
  36 #define DWMAC_CKEN_TX_IN        10
  37 #define DWMAC_CKEN_TXN_OUT      9
  38 #define DWMAC_CKEN_TX_OUT       8
  39 #define DWMAC_RX_SOURCE         7
  40 #define DWMAC_TX_SOURCE         6
  41 #define DWMAC_LOW_TX_SOURCE     4
  42 #define DWMAC_AUTO_TX_SOURCE    3
  43 #define DWMAC_RGMII             2
  44 #define DWMAC_SIMPLE_MUX        1
  45 #define DWMAC_CKEN_GTX          0
  46
  47 /* Delay register */
  48 #define DWMAC_TX_VARDELAY_SHIFT         0
  49 #define DWMAC_TXN_VARDELAY_SHIFT        8
  50 #define DWMAC_RX_VARDELAY_SHIFT         16
  51 #define DWMAC_RXN_VARDELAY_SHIFT        24
  52 #define DWMAC_TX_VARDELAY(d)            ((d) << DWMAC_TX_VARDELAY_SHIFT)
  53 #define DWMAC_TXN_VARDELAY(d)           ((d) << DWMAC_TXN_VARDELAY_SHIFT)
  54 #define DWMAC_RX_VARDELAY(d)            ((d) << DWMAC_RX_VARDELAY_SHIFT)
  55 #define DWMAC_RXN_VARDELAY(d)           ((d) << DWMAC_RXN_VARDELAY_SHIFT)
  56
  57 struct oxnas_dwmac {
  58         struct device   *dev;
  59         struct clk      *clk;
  60         struct regmap   *regmap;
  61 };
  62
  63 static int oxnas_dwmac_init(struct platform_device *pdev, void *priv)
  64 {
  65         struct oxnas_dwmac *dwmac = priv;
  66         unsigned int value;
  67         int ret;
  68
  69         /* Reset HW here before changing the glue configuration */
  70         ret = device_reset(dwmac->dev);
  71         if (ret)
  72                 return ret;
  73
  74         ret = clk_prepare_enable(dwmac->clk);
  75         if (ret)
  76                 return ret;
  77
  78         ret = regmap_read(dwmac->regmap, OXNAS_DWMAC_CTRL_REGOFFSET, &value);
  79         if (ret < 0) {
  80                 clk_disable_unprepare(dwmac->clk);
  81                 return ret;
  82         }
  83
  84         /* Enable GMII_GTXCLK to follow GMII_REFCLK, required for gigabit PHY */
  85         value |= BIT(DWMAC_CKEN_GTX)            |
  86                  /* Use simple mux for 25/125 Mhz clock switching */
  87                  BIT(DWMAC_SIMPLE_MUX)          |
  88                  /* set auto switch tx clock source */
  89                  BIT(DWMAC_AUTO_TX_SOURCE)      |
  90                  /* enable tx & rx vardelay */
  91                  BIT(DWMAC_CKEN_TX_OUT)         |
  92                  BIT(DWMAC_CKEN_TXN_OUT)        |
  93                  BIT(DWMAC_CKEN_TX_IN)          |
  94                  BIT(DWMAC_CKEN_RX_OUT)         |
  95                  BIT(DWMAC_CKEN_RXN_OUT)        |
  96                  BIT(DWMAC_CKEN_RX_IN);
  97         regmap_write(dwmac->regmap, OXNAS_DWMAC_CTRL_REGOFFSET, value);
  98
  99         /* set tx & rx vardelay */
 100         value = DWMAC_TX_VARDELAY(4)    |
 101                 DWMAC_TXN_VARDELAY(2)   |
 102                 DWMAC_RX_VARDELAY(10)   |
 103                 DWMAC_RXN_VARDELAY(8);
 104         regmap_write(dwmac->regmap, OXNAS_DWMAC_DELAY_REGOFFSET, value);
 105
 106         return 0;
 107 }
 108
 109 static void oxnas_dwmac_exit(struct platform_device *pdev, void *priv)
 110 {
 111         struct oxnas_dwmac *dwmac = priv;
 112
 113         clk_disable_unprepare(dwmac->clk);
 114 }
 115
 116 static int oxnas_dwmac_probe(struct platform_device *pdev)
 117 {
 118         struct plat_stmmacenet_data *plat_dat;
 119         struct stmmac_resources stmmac_res;
 120         struct oxnas_dwmac *dwmac;
 121         int ret;
 122
 123         ret = stmmac_get_platform_resources(pdev, &stmmac_res);
 124         if (ret)
 125                 return ret;
 126
 127         plat_dat = stmmac_probe_config_dt(pdev, &stmmac_res.mac);
 128         if (IS_ERR(plat_dat))
 129                 return PTR_ERR(plat_dat);
 130
 131         dwmac = devm_kzalloc(&pdev->dev, sizeof(*dwmac), GFP_KERNEL);
 132         if (!dwmac) {
 133                 ret = -ENOMEM;
 134                 goto err_remove_config_dt;
 135         }
 136
 137         dwmac->dev = &pdev->dev;
 138         plat_dat->bsp_priv = dwmac;
 139         plat_dat->init = oxnas_dwmac_init;
 140         plat_dat->exit = oxnas_dwmac_exit;
 141
 142         dwmac->regmap = syscon_regmap_lookup_by_phandle(pdev->dev.of_node,
 143                                                         "oxsemi,sys-ctrl");
 144         if (IS_ERR(dwmac->regmap)) {
 145                 dev_err(&pdev->dev, "failed to have sysctrl regmap\n");
 146                 ret = PTR_ERR(dwmac->regmap);
 147                 goto err_remove_config_dt;
 148         }
 149
 150         dwmac->clk = devm_clk_get(&pdev->dev, "gmac");
 151         if (IS_ERR(dwmac->clk)) {
 152                 ret = PTR_ERR(dwmac->clk);
 153                 goto err_remove_config_dt;
 154         }
 155
 156         ret = oxnas_dwmac_init(pdev, plat_dat->bsp_priv);
 157         if (ret)
 158                 goto err_remove_config_dt;
 159
 160         ret = stmmac_dvr_probe(&pdev->dev, plat_dat, &stmmac_res);
 161         if (ret)
 162                 goto err_dwmac_exit;
 163
 164
 165         return 0;
 166
 167 err_dwmac_exit:
 168         oxnas_dwmac_exit(pdev, plat_dat->bsp_priv);
 169 err_remove_config_dt:
 170         stmmac_remove_config_dt(pdev, plat_dat);
 171
 172         return ret;
 173 }
 174
 175 static const struct of_device_id oxnas_dwmac_match[] = {
 176         { .compatible = "oxsemi,ox820-dwmac" },
 177         { }
 178 };
 179 MODULE_DEVICE_TABLE(of, oxnas_dwmac_match);
 180
 181 static struct platform_driver oxnas_dwmac_driver = {
 182         .probe  = oxnas_dwmac_probe,
 183         .remove = stmmac_pltfr_remove,
 184         .driver = {
 185                 .name           = "oxnas-dwmac",
 186                 .pm             = &stmmac_pltfr_pm_ops,
 187                 .of_match_table = oxnas_dwmac_match,
 188         },
 189 };
 190 module_platform_driver(oxnas_dwmac_driver);
 191
 192 MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");
 193 MODULE_DESCRIPTION("Oxford Semiconductor OXNAS DWMAC glue layer");
 194 MODULE_LICENSE("GPL v2");