drivers/mmc/host/sdhci-tegra.c

   1 /*
   2  * Copyright (C) 2010 Google, Inc.
   3  *
   4  * This software is licensed under the terms of the GNU General Public
   5  * License version 2, as published by the Free Software Foundation, and
   6  * may be copied, distributed, and modified under those terms.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #include <linux/err.h>
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/platform_device.h>
  19 #include <linux/clk.h>
  20 #include <linux/io.h>
  21 #include <linux/of.h>
  22 #include <linux/of_device.h>
  23 #include <linux/of_gpio.h>
  24 #include <linux/gpio.h>
  25 #include <linux/mmc/card.h>
  26 #include <linux/mmc/host.h>
  27 #include <linux/mmc/slot-gpio.h>
  28
  29 #include <asm/gpio.h>
  30
  31 #include "sdhci-pltfm.h"
  32
  33 /* Tegra SDHOST controller vendor register definitions */
  34 #define SDHCI_TEGRA_VENDOR_MISC_CTRL            0x120
  35 #define SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300   0x20
  36
  37 #define NVQUIRK_FORCE_SDHCI_SPEC_200    BIT(0)
  38 #define NVQUIRK_ENABLE_BLOCK_GAP_DET    BIT(1)
  39 #define NVQUIRK_ENABLE_SDHCI_SPEC_300   BIT(2)
  40
  41 struct sdhci_tegra_soc_data {
  42         const struct sdhci_pltfm_data *pdata;
  43         u32 nvquirks;
  44 };
  45
  46 struct sdhci_tegra {
  47         const struct sdhci_tegra_soc_data *soc_data;
  48         int power_gpio;
  49 };
  50
  51 static u32 tegra_sdhci_readl(struct sdhci_host *host, int reg)
  52 {
  53         u32 val;
  54
  55         if (unlikely(reg == SDHCI_PRESENT_STATE)) {
  56                 /* Use wp_gpio here instead? */
  57                 val = readl(host->ioaddr + reg);
  58                 return val | SDHCI_WRITE_PROTECT;
  59         }
  60
  61         return readl(host->ioaddr + reg);
  62 }
  63
  64 static u16 tegra_sdhci_readw(struct sdhci_host *host, int reg)
  65 {
  66         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
  67         struct sdhci_tegra *tegra_host = pltfm_host->priv;
  68         const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
  69
  70         if (unlikely((soc_data->nvquirks & NVQUIRK_FORCE_SDHCI_SPEC_200) &&
  71                         (reg == SDHCI_HOST_VERSION))) {
  72                 /* Erratum: Version register is invalid in HW. */
  73                 return SDHCI_SPEC_200;
  74         }
  75
  76         return readw(host->ioaddr + reg);
  77 }
  78
  79 static void tegra_sdhci_writel(struct sdhci_host *host, u32 val, int reg)
  80 {
  81         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
  82         struct sdhci_tegra *tegra_host = pltfm_host->priv;
  83         const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
  84
  85         /* Seems like we're getting spurious timeout and crc errors, so
  86          * disable signalling of them. In case of real errors software
  87          * timers should take care of eventually detecting them.
  88          */
  89         if (unlikely(reg == SDHCI_SIGNAL_ENABLE))
  90                 val &= ~(SDHCI_INT_TIMEOUT|SDHCI_INT_CRC);
  91
  92         writel(val, host->ioaddr + reg);
  93
  94         if (unlikely((soc_data->nvquirks & NVQUIRK_ENABLE_BLOCK_GAP_DET) &&
  95                         (reg == SDHCI_INT_ENABLE))) {
  96                 /* Erratum: Must enable block gap interrupt detection */
  97                 u8 gap_ctrl = readb(host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
  98                 if (val & SDHCI_INT_CARD_INT)
  99                         gap_ctrl |= 0x8;
 100                 else
 101                         gap_ctrl &= ~0x8;
 102                 writeb(gap_ctrl, host->ioaddr + SDHCI_BLOCK_GAP_CONTROL);
 103         }
 104 }
 105
 106 static unsigned int tegra_sdhci_get_ro(struct sdhci_host *host)
 107 {
 108         return mmc_gpio_get_ro(host->mmc);
 109 }
 110
 111 static void tegra_sdhci_reset_exit(struct sdhci_host *host, u8 mask)
 112 {
 113         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 114         struct sdhci_tegra *tegra_host = pltfm_host->priv;
 115         const struct sdhci_tegra_soc_data *soc_data = tegra_host->soc_data;
 116
 117         if (!(mask & SDHCI_RESET_ALL))
 118                 return;
 119
 120         /* Erratum: Enable SDHCI spec v3.00 support */
 121         if (soc_data->nvquirks & NVQUIRK_ENABLE_SDHCI_SPEC_300) {
 122                 u32 misc_ctrl;
 123
 124                 misc_ctrl = sdhci_readb(host, SDHCI_TEGRA_VENDOR_MISC_CTRL);
 125                 misc_ctrl |= SDHCI_MISC_CTRL_ENABLE_SDHCI_SPEC_300;
 126                 sdhci_writeb(host, misc_ctrl, SDHCI_TEGRA_VENDOR_MISC_CTRL);
 127         }
 128 }
 129
 130 static int tegra_sdhci_buswidth(struct sdhci_host *host, int bus_width)
 131 {
 132         u32 ctrl;
 133
 134         ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
 135         if ((host->mmc->caps & MMC_CAP_8_BIT_DATA) &&
 136             (bus_width == MMC_BUS_WIDTH_8)) {
 137                 ctrl &= ~SDHCI_CTRL_4BITBUS;
 138                 ctrl |= SDHCI_CTRL_8BITBUS;
 139         } else {
 140                 ctrl &= ~SDHCI_CTRL_8BITBUS;
 141                 if (bus_width == MMC_BUS_WIDTH_4)
 142                         ctrl |= SDHCI_CTRL_4BITBUS;
 143                 else
 144                         ctrl &= ~SDHCI_CTRL_4BITBUS;
 145         }
 146         sdhci_writeb(host, ctrl, SDHCI_HOST_CONTROL);
 147         return 0;
 148 }
 149
 150 static const struct sdhci_ops tegra_sdhci_ops = {
 151         .get_ro     = tegra_sdhci_get_ro,
 152         .read_l     = tegra_sdhci_readl,
 153         .read_w     = tegra_sdhci_readw,
 154         .write_l    = tegra_sdhci_writel,
 155         .platform_bus_width = tegra_sdhci_buswidth,
 156         .platform_reset_exit = tegra_sdhci_reset_exit,
 157 };
 158
 159 static const struct sdhci_pltfm_data sdhci_tegra20_pdata = {
 160         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 161                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
 162                   SDHCI_QUIRK_NO_HISPD_BIT |
 163                   SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
 164         .ops  = &tegra_sdhci_ops,
 165 };
 166
 167 static struct sdhci_tegra_soc_data soc_data_tegra20 = {
 168         .pdata = &sdhci_tegra20_pdata,
 169         .nvquirks = NVQUIRK_FORCE_SDHCI_SPEC_200 |
 170                     NVQUIRK_ENABLE_BLOCK_GAP_DET,
 171 };
 172
 173 static const struct sdhci_pltfm_data sdhci_tegra30_pdata = {
 174         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 175                   SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 176                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
 177                   SDHCI_QUIRK_NO_HISPD_BIT |
 178                   SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
 179         .ops  = &tegra_sdhci_ops,
 180 };
 181
 182 static struct sdhci_tegra_soc_data soc_data_tegra30 = {
 183         .pdata = &sdhci_tegra30_pdata,
 184         .nvquirks = NVQUIRK_ENABLE_SDHCI_SPEC_300,
 185 };
 186
 187 static const struct sdhci_pltfm_data sdhci_tegra114_pdata = {
 188         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
 189                   SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
 190                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
 191                   SDHCI_QUIRK_NO_HISPD_BIT |
 192                   SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
 193         .ops  = &tegra_sdhci_ops,
 194 };
 195
 196 static struct sdhci_tegra_soc_data soc_data_tegra114 = {
 197         .pdata = &sdhci_tegra114_pdata,
 198 };
 199
 200 static const struct of_device_id sdhci_tegra_dt_match[] = {
 201         { .compatible = "nvidia,tegra114-sdhci", .data = &soc_data_tegra114 },
 202         { .compatible = "nvidia,tegra30-sdhci", .data = &soc_data_tegra30 },
 203         { .compatible = "nvidia,tegra20-sdhci", .data = &soc_data_tegra20 },
 204         {}
 205 };
 206 MODULE_DEVICE_TABLE(of, sdhci_tegra_dt_match);
 207
 208 static void sdhci_tegra_parse_dt(struct device *dev)
 209 {
 210         struct device_node *np = dev->of_node;
 211         struct sdhci_host *host = dev_get_drvdata(dev);
 212         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 213         struct sdhci_tegra *tegra_host = pltfm_host->priv;
 214
 215         tegra_host->power_gpio = of_get_named_gpio(np, "power-gpios", 0);
 216         mmc_of_parse(host->mmc);
 217 }
 218
 219 static int sdhci_tegra_probe(struct platform_device *pdev)
 220 {
 221         const struct of_device_id *match;
 222         const struct sdhci_tegra_soc_data *soc_data;
 223         struct sdhci_host *host;
 224         struct sdhci_pltfm_host *pltfm_host;
 225         struct sdhci_tegra *tegra_host;
 226         struct clk *clk;
 227         int rc;
 228
 229         match = of_match_device(sdhci_tegra_dt_match, &pdev->dev);
 230         if (!match)
 231                 return -EINVAL;
 232         soc_data = match->data;
 233
 234         host = sdhci_pltfm_init(pdev, soc_data->pdata);
 235         if (IS_ERR(host))
 236                 return PTR_ERR(host);
 237         pltfm_host = sdhci_priv(host);
 238
 239         tegra_host = devm_kzalloc(&pdev->dev, sizeof(*tegra_host), GFP_KERNEL);
 240         if (!tegra_host) {
 241                 dev_err(mmc_dev(host->mmc), "failed to allocate tegra_host\n");
 242                 rc = -ENOMEM;
 243                 goto err_alloc_tegra_host;
 244         }
 245         tegra_host->soc_data = soc_data;
 246         pltfm_host->priv = tegra_host;
 247
 248         sdhci_tegra_parse_dt(&pdev->dev);
 249
 250         if (gpio_is_valid(tegra_host->power_gpio)) {
 251                 rc = gpio_request(tegra_host->power_gpio, "sdhci_power");
 252                 if (rc) {
 253                         dev_err(mmc_dev(host->mmc),
 254                                 "failed to allocate power gpio\n");
 255                         goto err_power_req;
 256                 }
 257                 gpio_direction_output(tegra_host->power_gpio, 1);
 258         }
 259
 260         clk = clk_get(mmc_dev(host->mmc), NULL);
 261         if (IS_ERR(clk)) {
 262                 dev_err(mmc_dev(host->mmc), "clk err\n");
 263                 rc = PTR_ERR(clk);
 264                 goto err_clk_get;
 265         }
 266         clk_prepare_enable(clk);
 267         pltfm_host->clk = clk;
 268
 269         rc = sdhci_add_host(host);
 270         if (rc)
 271                 goto err_add_host;
 272
 273         return 0;
 274
 275 err_add_host:
 276         clk_disable_unprepare(pltfm_host->clk);
 277         clk_put(pltfm_host->clk);
 278 err_clk_get:
 279         if (gpio_is_valid(tegra_host->power_gpio))
 280                 gpio_free(tegra_host->power_gpio);
 281 err_power_req:
 282 err_alloc_tegra_host:
 283         sdhci_pltfm_free(pdev);
 284         return rc;
 285 }
 286
 287 static int sdhci_tegra_remove(struct platform_device *pdev)
 288 {
 289         struct sdhci_host *host = platform_get_drvdata(pdev);
 290         struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
 291         struct sdhci_tegra *tegra_host = pltfm_host->priv;
 292         int dead = (readl(host->ioaddr + SDHCI_INT_STATUS) == 0xffffffff);
 293
 294         sdhci_remove_host(host, dead);
 295
 296         if (gpio_is_valid(tegra_host->power_gpio))
 297                 gpio_free(tegra_host->power_gpio);
 298
 299         clk_disable_unprepare(pltfm_host->clk);
 300         clk_put(pltfm_host->clk);
 301
 302         sdhci_pltfm_free(pdev);
 303
 304         return 0;
 305 }
 306
 307 static struct platform_driver sdhci_tegra_driver = {
 308         .driver         = {
 309                 .name   = "sdhci-tegra",
 310                 .owner  = THIS_MODULE,
 311                 .of_match_table = sdhci_tegra_dt_match,
 312                 .pm     = SDHCI_PLTFM_PMOPS,
 313         },
 314         .probe          = sdhci_tegra_probe,
 315         .remove         = sdhci_tegra_remove,
 316 };
 317
 318 module_platform_driver(sdhci_tegra_driver);
 319
 320 MODULE_DESCRIPTION("SDHCI driver for Tegra");
 321 MODULE_AUTHOR("Google, Inc.");
 322 MODULE_LICENSE("GPL v2");