drivers/ata/pata_imx.c

   1 /*
   2  * Freescale iMX PATA driver
   3  *
   4  * Copyright (C) 2011 Arnaud Patard <arnaud.patard@rtp-net.org>
   5  *
   6  * Based on pata_platform - Copyright (C) 2006 - 2007  Paul Mundt
   7  *
   8  * This file is subject to the terms and conditions of the GNU General Public
   9  * License.  See the file "COPYING" in the main directory of this archive
  10  * for more details.
  11  *
  12  * TODO:
  13  * - dmaengine support
  14  */
  15
  16 #include <linux/ata.h>
  17 #include <linux/clk.h>
  18 #include <linux/libata.h>
  19 #include <linux/module.h>
  20 #include <linux/mod_devicetable.h>
  21 #include <linux/platform_device.h>
  22
  23 #define DRV_NAME "pata_imx"
  24
  25 #define PATA_IMX_ATA_TIME_OFF           0x00
  26 #define PATA_IMX_ATA_TIME_ON            0x01
  27 #define PATA_IMX_ATA_TIME_1             0x02
  28 #define PATA_IMX_ATA_TIME_2W            0x03
  29 #define PATA_IMX_ATA_TIME_2R            0x04
  30 #define PATA_IMX_ATA_TIME_AX            0x05
  31 #define PATA_IMX_ATA_TIME_PIO_RDX       0x06
  32 #define PATA_IMX_ATA_TIME_4             0x07
  33 #define PATA_IMX_ATA_TIME_9             0x08
  34
  35 #define PATA_IMX_ATA_CONTROL            0x24
  36 #define PATA_IMX_ATA_CTRL_FIFO_RST_B    (1<<7)
  37 #define PATA_IMX_ATA_CTRL_ATA_RST_B     (1<<6)
  38 #define PATA_IMX_ATA_CTRL_IORDY_EN      (1<<0)
  39 #define PATA_IMX_ATA_INT_EN             0x2C
  40 #define PATA_IMX_ATA_INTR_ATA_INTRQ2    (1<<3)
  41 #define PATA_IMX_DRIVE_DATA             0xA0
  42 #define PATA_IMX_DRIVE_CONTROL          0xD8
  43
  44 static u32 pio_t4[] = { 30,  20,  15,  10,  10 };
  45 static u32 pio_t9[] = { 20,  15,  10,  10,  10 };
  46 static u32 pio_tA[] = { 35,  35,  35,  35,  35 };
  47
  48 struct pata_imx_priv {
  49         struct clk *clk;
  50         /* timings/interrupt/control regs */
  51         void __iomem *host_regs;
  52         u32 ata_ctl;
  53 };
  54
  55 static void pata_imx_set_timing(struct ata_device *adev,
  56                                 struct pata_imx_priv *priv)
  57 {
  58         struct ata_timing timing;
  59         unsigned long clkrate;
  60         u32 T, mode;
  61
  62         clkrate = clk_get_rate(priv->clk);
  63
  64         if (adev->pio_mode < XFER_PIO_0 || adev->pio_mode > XFER_PIO_4 ||
  65             !clkrate)
  66                 return;
  67
  68         T = 1000000000 / clkrate;
  69         ata_timing_compute(adev, adev->pio_mode, &timing, T * 1000, 0);
  70
  71         mode = adev->pio_mode - XFER_PIO_0;
  72
  73         writeb(3, priv->host_regs + PATA_IMX_ATA_TIME_OFF);
  74         writeb(3, priv->host_regs + PATA_IMX_ATA_TIME_ON);
  75         writeb(timing.setup, priv->host_regs + PATA_IMX_ATA_TIME_1);
  76         writeb(timing.act8b, priv->host_regs + PATA_IMX_ATA_TIME_2W);
  77         writeb(timing.act8b, priv->host_regs + PATA_IMX_ATA_TIME_2R);
  78         writeb(1, priv->host_regs + PATA_IMX_ATA_TIME_PIO_RDX);
  79
  80         writeb(pio_t4[mode] / T + 1, priv->host_regs + PATA_IMX_ATA_TIME_4);
  81         writeb(pio_t9[mode] / T + 1, priv->host_regs + PATA_IMX_ATA_TIME_9);
  82         writeb(pio_tA[mode] / T + 1, priv->host_regs + PATA_IMX_ATA_TIME_AX);
  83 }
  84
  85 static void pata_imx_set_piomode(struct ata_port *ap, struct ata_device *adev)
  86 {
  87         struct pata_imx_priv *priv = ap->host->private_data;
  88         u32 val;
  89
  90         pata_imx_set_timing(adev, priv);
  91
  92         val = __raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
  93         if (ata_pio_need_iordy(adev))
  94                 val |= PATA_IMX_ATA_CTRL_IORDY_EN;
  95         else
  96                 val &= ~PATA_IMX_ATA_CTRL_IORDY_EN;
  97         __raw_writel(val, priv->host_regs + PATA_IMX_ATA_CONTROL);
  98 }
  99
 100 static struct scsi_host_template pata_imx_sht = {
 101         ATA_PIO_SHT(DRV_NAME),
 102 };
 103
 104 static struct ata_port_operations pata_imx_port_ops = {
 105         .inherits               = &ata_sff_port_ops,
 106         .sff_data_xfer          = ata_sff_data_xfer32,
 107         .cable_detect           = ata_cable_unknown,
 108         .set_piomode            = pata_imx_set_piomode,
 109 };
 110
 111 static void pata_imx_setup_port(struct ata_ioports *ioaddr)
 112 {
 113         /* Fixup the port shift for platforms that need it */
 114         ioaddr->data_addr       = ioaddr->cmd_addr + (ATA_REG_DATA    << 2);
 115         ioaddr->error_addr      = ioaddr->cmd_addr + (ATA_REG_ERR     << 2);
 116         ioaddr->feature_addr    = ioaddr->cmd_addr + (ATA_REG_FEATURE << 2);
 117         ioaddr->nsect_addr      = ioaddr->cmd_addr + (ATA_REG_NSECT   << 2);
 118         ioaddr->lbal_addr       = ioaddr->cmd_addr + (ATA_REG_LBAL    << 2);
 119         ioaddr->lbam_addr       = ioaddr->cmd_addr + (ATA_REG_LBAM    << 2);
 120         ioaddr->lbah_addr       = ioaddr->cmd_addr + (ATA_REG_LBAH    << 2);
 121         ioaddr->device_addr     = ioaddr->cmd_addr + (ATA_REG_DEVICE  << 2);
 122         ioaddr->status_addr     = ioaddr->cmd_addr + (ATA_REG_STATUS  << 2);
 123         ioaddr->command_addr    = ioaddr->cmd_addr + (ATA_REG_CMD     << 2);
 124 }
 125
 126 static int pata_imx_probe(struct platform_device *pdev)
 127 {
 128         struct ata_host *host;
 129         struct ata_port *ap;
 130         struct pata_imx_priv *priv;
 131         int irq = 0;
 132         struct resource *io_res;
 133         int ret;
 134
 135         irq = platform_get_irq(pdev, 0);
 136         if (irq < 0)
 137                 return irq;
 138
 139         priv = devm_kzalloc(&pdev->dev,
 140                                 sizeof(struct pata_imx_priv), GFP_KERNEL);
 141         if (!priv)
 142                 return -ENOMEM;
 143
 144         priv->clk = devm_clk_get(&pdev->dev, NULL);
 145         if (IS_ERR(priv->clk)) {
 146                 dev_err(&pdev->dev, "Failed to get clock\n");
 147                 return PTR_ERR(priv->clk);
 148         }
 149
 150         ret = clk_prepare_enable(priv->clk);
 151         if (ret)
 152                 return ret;
 153
 154         host = ata_host_alloc(&pdev->dev, 1);
 155         if (!host) {
 156                 ret = -ENOMEM;
 157                 goto err;
 158         }
 159
 160         host->private_data = priv;
 161         ap = host->ports[0];
 162
 163         ap->ops = &pata_imx_port_ops;
 164         ap->pio_mask = ATA_PIO4;
 165         ap->flags |= ATA_FLAG_SLAVE_POSS;
 166
 167         io_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 168         priv->host_regs = devm_ioremap_resource(&pdev->dev, io_res);
 169         if (IS_ERR(priv->host_regs)) {
 170                 ret = PTR_ERR(priv->host_regs);
 171                 goto err;
 172         }
 173
 174         ap->ioaddr.cmd_addr = priv->host_regs + PATA_IMX_DRIVE_DATA;
 175         ap->ioaddr.ctl_addr = priv->host_regs + PATA_IMX_DRIVE_CONTROL;
 176
 177         ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr;
 178
 179         pata_imx_setup_port(&ap->ioaddr);
 180
 181         ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
 182                 (unsigned long long)io_res->start + PATA_IMX_DRIVE_DATA,
 183                 (unsigned long long)io_res->start + PATA_IMX_DRIVE_CONTROL);
 184
 185         /* deassert resets */
 186         __raw_writel(PATA_IMX_ATA_CTRL_FIFO_RST_B |
 187                         PATA_IMX_ATA_CTRL_ATA_RST_B,
 188                         priv->host_regs + PATA_IMX_ATA_CONTROL);
 189         /* enable interrupts */
 190         __raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
 191                         priv->host_regs + PATA_IMX_ATA_INT_EN);
 192
 193         /* activate */
 194         ret = ata_host_activate(host, irq, ata_sff_interrupt, 0,
 195                                 &pata_imx_sht);
 196
 197         if (ret)
 198                 goto err;
 199
 200         return 0;
 201 err:
 202         clk_disable_unprepare(priv->clk);
 203
 204         return ret;
 205 }
 206
 207 static int pata_imx_remove(struct platform_device *pdev)
 208 {
 209         struct ata_host *host = platform_get_drvdata(pdev);
 210         struct pata_imx_priv *priv = host->private_data;
 211
 212         ata_host_detach(host);
 213
 214         __raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
 215
 216         clk_disable_unprepare(priv->clk);
 217
 218         return 0;
 219 }
 220
 221 #ifdef CONFIG_PM_SLEEP
 222 static int pata_imx_suspend(struct device *dev)
 223 {
 224         struct ata_host *host = dev_get_drvdata(dev);
 225         struct pata_imx_priv *priv = host->private_data;
 226         int ret;
 227
 228         ret = ata_host_suspend(host, PMSG_SUSPEND);
 229         if (!ret) {
 230                 __raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
 231                 priv->ata_ctl =
 232                         __raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
 233                 clk_disable_unprepare(priv->clk);
 234         }
 235
 236         return ret;
 237 }
 238
 239 static int pata_imx_resume(struct device *dev)
 240 {
 241         struct ata_host *host = dev_get_drvdata(dev);
 242         struct pata_imx_priv *priv = host->private_data;
 243
 244         int ret = clk_prepare_enable(priv->clk);
 245         if (ret)
 246                 return ret;
 247
 248         __raw_writel(priv->ata_ctl, priv->host_regs + PATA_IMX_ATA_CONTROL);
 249
 250         __raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
 251                         priv->host_regs + PATA_IMX_ATA_INT_EN);
 252
 253         ata_host_resume(host);
 254
 255         return 0;
 256 }
 257 #endif
 258
 259 static SIMPLE_DEV_PM_OPS(pata_imx_pm_ops, pata_imx_suspend, pata_imx_resume);
 260
 261 static const struct of_device_id imx_pata_dt_ids[] = {
 262         {
 263                 .compatible = "fsl,imx27-pata",
 264         }, {
 265                 /* sentinel */
 266         }
 267 };
 268 MODULE_DEVICE_TABLE(of, imx_pata_dt_ids);
 269
 270 static struct platform_driver pata_imx_driver = {
 271         .probe          = pata_imx_probe,
 272         .remove         = pata_imx_remove,
 273         .driver = {
 274                 .name           = DRV_NAME,
 275                 .of_match_table = imx_pata_dt_ids,
 276                 .pm             = &pata_imx_pm_ops,
 277         },
 278 };
 279
 280 module_platform_driver(pata_imx_driver);
 281
 282 MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>");
 283 MODULE_DESCRIPTION("low-level driver for iMX PATA");
 284 MODULE_LICENSE("GPL");
 285 MODULE_ALIAS("platform:" DRV_NAME);