drivers/ata/ahci_st.c

   1 /*
   2  * Copyright (C) 2012 STMicroelectronics Limited
   3  *
   4  * Authors: Francesco Virlinzi <francesco.virlinzi@st.com>
   5  *          Alexandre Torgue <alexandre.torgue@st.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/init.h>
  13 #include <linux/module.h>
  14 #include <linux/export.h>
  15 #include <linux/platform_device.h>
  16 #include <linux/clk.h>
  17 #include <linux/of.h>
  18 #include <linux/ahci_platform.h>
  19 #include <linux/libata.h>
  20 #include <linux/reset.h>
  21 #include <linux/io.h>
  22 #include <linux/dma-mapping.h>
  23
  24 #include "ahci.h"
  25
  26 #define DRV_NAME  "st_ahci"
  27
  28 #define ST_AHCI_OOBR                    0xbc
  29 #define ST_AHCI_OOBR_WE                 BIT(31)
  30 #define ST_AHCI_OOBR_CWMIN_SHIFT        24
  31 #define ST_AHCI_OOBR_CWMAX_SHIFT        16
  32 #define ST_AHCI_OOBR_CIMIN_SHIFT        8
  33 #define ST_AHCI_OOBR_CIMAX_SHIFT        0
  34
  35 struct st_ahci_drv_data {
  36         struct platform_device *ahci;
  37         struct reset_control *pwr;
  38         struct reset_control *sw_rst;
  39         struct reset_control *pwr_rst;
  40 };
  41
  42 static void st_ahci_configure_oob(void __iomem *mmio)
  43 {
  44         unsigned long old_val, new_val;
  45
  46         new_val = (0x02 << ST_AHCI_OOBR_CWMIN_SHIFT) |
  47                   (0x04 << ST_AHCI_OOBR_CWMAX_SHIFT) |
  48                   (0x08 << ST_AHCI_OOBR_CIMIN_SHIFT) |
  49                   (0x0C << ST_AHCI_OOBR_CIMAX_SHIFT);
  50
  51         old_val = readl(mmio + ST_AHCI_OOBR);
  52         writel(old_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
  53         writel(new_val | ST_AHCI_OOBR_WE, mmio + ST_AHCI_OOBR);
  54         writel(new_val, mmio + ST_AHCI_OOBR);
  55 }
  56
  57 static int st_ahci_deassert_resets(struct ahci_host_priv *hpriv,
  58                                 struct device *dev)
  59 {
  60         struct st_ahci_drv_data *drv_data = hpriv->plat_data;
  61         int err;
  62
  63         if (drv_data->pwr) {
  64                 err = reset_control_deassert(drv_data->pwr);
  65                 if (err) {
  66                         dev_err(dev, "unable to bring out of pwrdwn\n");
  67                         return err;
  68                 }
  69         }
  70
  71         if (drv_data->sw_rst) {
  72                 err = reset_control_deassert(drv_data->sw_rst);
  73                 if (err) {
  74                         dev_err(dev, "unable to bring out of sw-rst\n");
  75                         return err;
  76                 }
  77         }
  78
  79         if (drv_data->pwr_rst) {
  80                 err = reset_control_deassert(drv_data->pwr_rst);
  81                 if (err) {
  82                         dev_err(dev, "unable to bring out of pwr-rst\n");
  83                         return err;
  84                 }
  85         }
  86
  87         return 0;
  88 }
  89
  90 static void st_ahci_host_stop(struct ata_host *host)
  91 {
  92         struct ahci_host_priv *hpriv = host->private_data;
  93         struct st_ahci_drv_data *drv_data = hpriv->plat_data;
  94         struct device *dev = host->dev;
  95         int err;
  96
  97         if (drv_data->pwr) {
  98                 err = reset_control_assert(drv_data->pwr);
  99                 if (err)
 100                         dev_err(dev, "unable to pwrdwn\n");
 101         }
 102
 103         ahci_platform_disable_resources(hpriv);
 104 }
 105
 106 static int st_ahci_probe_resets(struct ahci_host_priv *hpriv,
 107                                 struct device *dev)
 108 {
 109         struct st_ahci_drv_data *drv_data = hpriv->plat_data;
 110
 111         drv_data->pwr = devm_reset_control_get(dev, "pwr-dwn");
 112         if (IS_ERR(drv_data->pwr)) {
 113                 dev_info(dev, "power reset control not defined\n");
 114                 drv_data->pwr = NULL;
 115         }
 116
 117         drv_data->sw_rst = devm_reset_control_get(dev, "sw-rst");
 118         if (IS_ERR(drv_data->sw_rst)) {
 119                 dev_info(dev, "soft reset control not defined\n");
 120                 drv_data->sw_rst = NULL;
 121         }
 122
 123         drv_data->pwr_rst = devm_reset_control_get(dev, "pwr-rst");
 124         if (IS_ERR(drv_data->pwr_rst)) {
 125                 dev_dbg(dev, "power soft reset control not defined\n");
 126                 drv_data->pwr_rst = NULL;
 127         }
 128
 129         return st_ahci_deassert_resets(hpriv, dev);
 130 }
 131
 132 static struct ata_port_operations st_ahci_port_ops = {
 133         .inherits       = &ahci_platform_ops,
 134         .host_stop      = st_ahci_host_stop,
 135 };
 136
 137 static const struct ata_port_info st_ahci_port_info = {
 138         .flags          = AHCI_FLAG_COMMON,
 139         .pio_mask       = ATA_PIO4,
 140         .udma_mask      = ATA_UDMA6,
 141         .port_ops       = &st_ahci_port_ops,
 142 };
 143
 144 static struct scsi_host_template ahci_platform_sht = {
 145         AHCI_SHT(DRV_NAME),
 146 };
 147
 148 static int st_ahci_probe(struct platform_device *pdev)
 149 {
 150         struct st_ahci_drv_data *drv_data;
 151         struct ahci_host_priv *hpriv;
 152         int err;
 153
 154         drv_data = devm_kzalloc(&pdev->dev, sizeof(*drv_data), GFP_KERNEL);
 155         if (!drv_data)
 156                 return -ENOMEM;
 157
 158         hpriv = ahci_platform_get_resources(pdev);
 159         if (IS_ERR(hpriv))
 160                 return PTR_ERR(hpriv);
 161         hpriv->plat_data = drv_data;
 162
 163         err = st_ahci_probe_resets(hpriv, &pdev->dev);
 164         if (err)
 165                 return err;
 166
 167         err = ahci_platform_enable_resources(hpriv);
 168         if (err)
 169                 return err;
 170
 171         st_ahci_configure_oob(hpriv->mmio);
 172
 173         err = ahci_platform_init_host(pdev, hpriv, &st_ahci_port_info,
 174                                       &ahci_platform_sht);
 175         if (err) {
 176                 ahci_platform_disable_resources(hpriv);
 177                 return err;
 178         }
 179
 180         return 0;
 181 }
 182
 183 #ifdef CONFIG_PM_SLEEP
 184 static int st_ahci_suspend(struct device *dev)
 185 {
 186         struct ata_host *host = dev_get_drvdata(dev);
 187         struct ahci_host_priv *hpriv = host->private_data;
 188         struct st_ahci_drv_data *drv_data = hpriv->plat_data;
 189         int err;
 190
 191         err = ahci_platform_suspend_host(dev);
 192         if (err)
 193                 return err;
 194
 195         if (drv_data->pwr) {
 196                 err = reset_control_assert(drv_data->pwr);
 197                 if (err) {
 198                         dev_err(dev, "unable to pwrdwn");
 199                         return err;
 200                 }
 201         }
 202
 203         ahci_platform_disable_resources(hpriv);
 204
 205         return 0;
 206 }
 207
 208 static int st_ahci_resume(struct device *dev)
 209 {
 210         struct ata_host *host = dev_get_drvdata(dev);
 211         struct ahci_host_priv *hpriv = host->private_data;
 212         int err;
 213
 214         err = ahci_platform_enable_resources(hpriv);
 215         if (err)
 216                 return err;
 217
 218         err = st_ahci_deassert_resets(hpriv, dev);
 219         if (err) {
 220                 ahci_platform_disable_resources(hpriv);
 221                 return err;
 222         }
 223
 224         st_ahci_configure_oob(hpriv->mmio);
 225
 226         return ahci_platform_resume_host(dev);
 227 }
 228 #endif
 229
 230 static SIMPLE_DEV_PM_OPS(st_ahci_pm_ops, st_ahci_suspend, st_ahci_resume);
 231
 232 static const struct of_device_id st_ahci_match[] = {
 233         { .compatible = "st,ahci", },
 234         {},
 235 };
 236 MODULE_DEVICE_TABLE(of, st_ahci_match);
 237
 238 static struct platform_driver st_ahci_driver = {
 239         .driver = {
 240                 .name = DRV_NAME,
 241                 .pm = &st_ahci_pm_ops,
 242                 .of_match_table = of_match_ptr(st_ahci_match),
 243         },
 244         .probe = st_ahci_probe,
 245         .remove = ata_platform_remove_one,
 246 };
 247 module_platform_driver(st_ahci_driver);
 248
 249 MODULE_AUTHOR("Alexandre Torgue <alexandre.torgue@st.com>");
 250 MODULE_AUTHOR("Francesco Virlinzi <francesco.virlinzi@st.com>");
 251 MODULE_DESCRIPTION("STMicroelectronics SATA AHCI Driver");
 252 MODULE_LICENSE("GPL v2");