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