linux/drivers/ata/pata_imx.c
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   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
  44static u32 pio_t4[] = { 30,  20,  15,  10,  10 };
  45static u32 pio_t9[] = { 20,  15,  10,  10,  10 };
  46static u32 pio_tA[] = { 35,  35,  35,  35,  35 };
  47
  48struct pata_imx_priv {
  49        struct clk *clk;
  50        /* timings/interrupt/control regs */
  51        void __iomem *host_regs;
  52        u32 ata_ctl;
  53};
  54
  55static 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
  85static 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
 100static struct scsi_host_template pata_imx_sht = {
 101        ATA_PIO_SHT(DRV_NAME),
 102};
 103
 104static 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
 111static 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
 126static 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;
 201err:
 202        clk_disable_unprepare(priv->clk);
 203
 204        return ret;
 205}
 206
 207static 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
 222static 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
 239static 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
 259static SIMPLE_DEV_PM_OPS(pata_imx_pm_ops, pata_imx_suspend, pata_imx_resume);
 260
 261static const struct of_device_id imx_pata_dt_ids[] = {
 262        {
 263                .compatible = "fsl,imx27-pata",
 264        }, {
 265                /* sentinel */
 266        }
 267};
 268MODULE_DEVICE_TABLE(of, imx_pata_dt_ids);
 269
 270static 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
 280module_platform_driver(pata_imx_driver);
 281
 282MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>");
 283MODULE_DESCRIPTION("low-level driver for iMX PATA");
 284MODULE_LICENSE("GPL");
 285MODULE_ALIAS("platform:" DRV_NAME);
 286