drivers/ata/pata_imx.c

0001 /*
0002  * Freescale iMX PATA driver
0003  *
0004  * Copyright (C) 2011 Arnaud Patard <arnaud.patard@rtp-net.org>
0005  *
0006  * Based on pata_platform - Copyright (C) 2006 - 2007  Paul Mundt
0007  *
0008  * This file is subject to the terms and conditions of the GNU General Public
0009  * License.  See the file "COPYING" in the main directory of this archive
0010  * for more details.
0011  *
0012  * TODO:
0013  * - dmaengine support
0014  */
0015
0016 #include <linux/ata.h>
0017 #include <linux/clk.h>
0018 #include <linux/libata.h>
0019 #include <linux/module.h>
0020 #include <linux/mod_devicetable.h>
0021 #include <linux/platform_device.h>
0022
0023 #define DRV_NAME "pata_imx"
0024
0025 #define PATA_IMX_ATA_TIME_OFF       0x00
0026 #define PATA_IMX_ATA_TIME_ON        0x01
0027 #define PATA_IMX_ATA_TIME_1     0x02
0028 #define PATA_IMX_ATA_TIME_2W        0x03
0029 #define PATA_IMX_ATA_TIME_2R        0x04
0030 #define PATA_IMX_ATA_TIME_AX        0x05
0031 #define PATA_IMX_ATA_TIME_PIO_RDX   0x06
0032 #define PATA_IMX_ATA_TIME_4     0x07
0033 #define PATA_IMX_ATA_TIME_9     0x08
0034
0035 #define PATA_IMX_ATA_CONTROL        0x24
0036 #define PATA_IMX_ATA_CTRL_FIFO_RST_B    (1<<7)
0037 #define PATA_IMX_ATA_CTRL_ATA_RST_B (1<<6)
0038 #define PATA_IMX_ATA_CTRL_IORDY_EN  (1<<0)
0039 #define PATA_IMX_ATA_INT_EN     0x2C
0040 #define PATA_IMX_ATA_INTR_ATA_INTRQ2    (1<<3)
0041 #define PATA_IMX_DRIVE_DATA     0xA0
0042 #define PATA_IMX_DRIVE_CONTROL      0xD8
0043
0044 static u32 pio_t4[] = { 30,  20,  15,  10,  10 };
0045 static u32 pio_t9[] = { 20,  15,  10,  10,  10 };
0046 static u32 pio_tA[] = { 35,  35,  35,  35,  35 };
0047
0048 struct pata_imx_priv {
0049     struct clk *clk;
0050     /* timings/interrupt/control regs */
0051     void __iomem *host_regs;
0052     u32 ata_ctl;
0053 };
0054
0055 static void pata_imx_set_timing(struct ata_device *adev,
0056                 struct pata_imx_priv *priv)
0057 {
0058     struct ata_timing timing;
0059     unsigned long clkrate;
0060     u32 T, mode;
0061
0062     clkrate = clk_get_rate(priv->clk);
0063
0064     if (adev->pio_mode < XFER_PIO_0 || adev->pio_mode > XFER_PIO_4 ||
0065         !clkrate)
0066         return;
0067
0068     T = 1000000000 / clkrate;
0069     ata_timing_compute(adev, adev->pio_mode, &timing, T * 1000, 0);
0070
0071     mode = adev->pio_mode - XFER_PIO_0;
0072
0073     writeb(3, priv->host_regs + PATA_IMX_ATA_TIME_OFF);
0074     writeb(3, priv->host_regs + PATA_IMX_ATA_TIME_ON);
0075     writeb(timing.setup, priv->host_regs + PATA_IMX_ATA_TIME_1);
0076     writeb(timing.act8b, priv->host_regs + PATA_IMX_ATA_TIME_2W);
0077     writeb(timing.act8b, priv->host_regs + PATA_IMX_ATA_TIME_2R);
0078     writeb(1, priv->host_regs + PATA_IMX_ATA_TIME_PIO_RDX);
0079
0080     writeb(pio_t4[mode] / T + 1, priv->host_regs + PATA_IMX_ATA_TIME_4);
0081     writeb(pio_t9[mode] / T + 1, priv->host_regs + PATA_IMX_ATA_TIME_9);
0082     writeb(pio_tA[mode] / T + 1, priv->host_regs + PATA_IMX_ATA_TIME_AX);
0083 }
0084
0085 static void pata_imx_set_piomode(struct ata_port *ap, struct ata_device *adev)
0086 {
0087     struct pata_imx_priv *priv = ap->host->private_data;
0088     u32 val;
0089
0090     pata_imx_set_timing(adev, priv);
0091
0092     val = __raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
0093     if (ata_pio_need_iordy(adev))
0094         val |= PATA_IMX_ATA_CTRL_IORDY_EN;
0095     else
0096         val &= ~PATA_IMX_ATA_CTRL_IORDY_EN;
0097     __raw_writel(val, priv->host_regs + PATA_IMX_ATA_CONTROL);
0098 }
0099
0100 static struct scsi_host_template pata_imx_sht = {
0101     ATA_PIO_SHT(DRV_NAME),
0102 };
0103
0104 static struct ata_port_operations pata_imx_port_ops = {
0105     .inherits       = &ata_sff_port_ops,
0106     .sff_data_xfer      = ata_sff_data_xfer32,
0107     .cable_detect       = ata_cable_unknown,
0108     .set_piomode        = pata_imx_set_piomode,
0109 };
0110
0111 static void pata_imx_setup_port(struct ata_ioports *ioaddr)
0112 {
0113     /* Fixup the port shift for platforms that need it */
0114     ioaddr->data_addr   = ioaddr->cmd_addr + (ATA_REG_DATA    << 2);
0115     ioaddr->error_addr  = ioaddr->cmd_addr + (ATA_REG_ERR     << 2);
0116     ioaddr->feature_addr    = ioaddr->cmd_addr + (ATA_REG_FEATURE << 2);
0117     ioaddr->nsect_addr  = ioaddr->cmd_addr + (ATA_REG_NSECT   << 2);
0118     ioaddr->lbal_addr   = ioaddr->cmd_addr + (ATA_REG_LBAL    << 2);
0119     ioaddr->lbam_addr   = ioaddr->cmd_addr + (ATA_REG_LBAM    << 2);
0120     ioaddr->lbah_addr   = ioaddr->cmd_addr + (ATA_REG_LBAH    << 2);
0121     ioaddr->device_addr = ioaddr->cmd_addr + (ATA_REG_DEVICE  << 2);
0122     ioaddr->status_addr = ioaddr->cmd_addr + (ATA_REG_STATUS  << 2);
0123     ioaddr->command_addr    = ioaddr->cmd_addr + (ATA_REG_CMD     << 2);
0124 }
0125
0126 static int pata_imx_probe(struct platform_device *pdev)
0127 {
0128     struct ata_host *host;
0129     struct ata_port *ap;
0130     struct pata_imx_priv *priv;
0131     int irq = 0;
0132     struct resource *io_res;
0133     int ret;
0134
0135     irq = platform_get_irq(pdev, 0);
0136     if (irq < 0)
0137         return irq;
0138
0139     priv = devm_kzalloc(&pdev->dev,
0140                 sizeof(struct pata_imx_priv), GFP_KERNEL);
0141     if (!priv)
0142         return -ENOMEM;
0143
0144     priv->clk = devm_clk_get(&pdev->dev, NULL);
0145     if (IS_ERR(priv->clk)) {
0146         dev_err(&pdev->dev, "Failed to get clock\n");
0147         return PTR_ERR(priv->clk);
0148     }
0149
0150     ret = clk_prepare_enable(priv->clk);
0151     if (ret)
0152         return ret;
0153
0154     host = ata_host_alloc(&pdev->dev, 1);
0155     if (!host) {
0156         ret = -ENOMEM;
0157         goto err;
0158     }
0159
0160     host->private_data = priv;
0161     ap = host->ports[0];
0162
0163     ap->ops = &pata_imx_port_ops;
0164     ap->pio_mask = ATA_PIO4;
0165     ap->flags |= ATA_FLAG_SLAVE_POSS;
0166
0167     io_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
0168     priv->host_regs = devm_ioremap_resource(&pdev->dev, io_res);
0169     if (IS_ERR(priv->host_regs)) {
0170         ret = PTR_ERR(priv->host_regs);
0171         goto err;
0172     }
0173
0174     ap->ioaddr.cmd_addr = priv->host_regs + PATA_IMX_DRIVE_DATA;
0175     ap->ioaddr.ctl_addr = priv->host_regs + PATA_IMX_DRIVE_CONTROL;
0176
0177     ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr;
0178
0179     pata_imx_setup_port(&ap->ioaddr);
0180
0181     ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
0182         (unsigned long long)io_res->start + PATA_IMX_DRIVE_DATA,
0183         (unsigned long long)io_res->start + PATA_IMX_DRIVE_CONTROL);
0184
0185     /* deassert resets */
0186     __raw_writel(PATA_IMX_ATA_CTRL_FIFO_RST_B |
0187             PATA_IMX_ATA_CTRL_ATA_RST_B,
0188             priv->host_regs + PATA_IMX_ATA_CONTROL);
0189     /* enable interrupts */
0190     __raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
0191             priv->host_regs + PATA_IMX_ATA_INT_EN);
0192
0193     /* activate */
0194     ret = ata_host_activate(host, irq, ata_sff_interrupt, 0,
0195                 &pata_imx_sht);
0196
0197     if (ret)
0198         goto err;
0199
0200     return 0;
0201 err:
0202     clk_disable_unprepare(priv->clk);
0203
0204     return ret;
0205 }
0206
0207 static int pata_imx_remove(struct platform_device *pdev)
0208 {
0209     struct ata_host *host = platform_get_drvdata(pdev);
0210     struct pata_imx_priv *priv = host->private_data;
0211
0212     ata_host_detach(host);
0213
0214     __raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
0215
0216     clk_disable_unprepare(priv->clk);
0217
0218     return 0;
0219 }
0220
0221 #ifdef CONFIG_PM_SLEEP
0222 static int pata_imx_suspend(struct device *dev)
0223 {
0224     struct ata_host *host = dev_get_drvdata(dev);
0225     struct pata_imx_priv *priv = host->private_data;
0226
0227     ata_host_suspend(host, PMSG_SUSPEND);
0228
0229     __raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
0230     priv->ata_ctl = __raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
0231     clk_disable_unprepare(priv->clk);
0232
0233     return 0;
0234 }
0235
0236 static int pata_imx_resume(struct device *dev)
0237 {
0238     struct ata_host *host = dev_get_drvdata(dev);
0239     struct pata_imx_priv *priv = host->private_data;
0240
0241     int ret = clk_prepare_enable(priv->clk);
0242     if (ret)
0243         return ret;
0244
0245     __raw_writel(priv->ata_ctl, priv->host_regs + PATA_IMX_ATA_CONTROL);
0246
0247     __raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
0248             priv->host_regs + PATA_IMX_ATA_INT_EN);
0249
0250     ata_host_resume(host);
0251
0252     return 0;
0253 }
0254 #endif
0255
0256 static SIMPLE_DEV_PM_OPS(pata_imx_pm_ops, pata_imx_suspend, pata_imx_resume);
0257
0258 static const struct of_device_id imx_pata_dt_ids[] = {
0259     {
0260         .compatible = "fsl,imx27-pata",
0261     }, {
0262         /* sentinel */
0263     }
0264 };
0265 MODULE_DEVICE_TABLE(of, imx_pata_dt_ids);
0266
0267 static struct platform_driver pata_imx_driver = {
0268     .probe      = pata_imx_probe,
0269     .remove     = pata_imx_remove,
0270     .driver = {
0271         .name       = DRV_NAME,
0272         .of_match_table = imx_pata_dt_ids,
0273         .pm     = &pata_imx_pm_ops,
0274     },
0275 };
0276
0277 module_platform_driver(pata_imx_driver);
0278
0279 MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>");
0280 MODULE_DESCRIPTION("low-level driver for iMX PATA");
0281 MODULE_LICENSE("GPL");
0282 MODULE_ALIAS("platform:" DRV_NAME);