ata: Add iMX pata support
Arnaud Patard (Rtp) [Tue, 26 Jul 2011 14:58:19 +0000 (16:58 +0200)]
Add basic support for pata on iMX. It has been tested only on imx51.
SDMA support will probably be added later so this version supports only
PIO.

v2:
  - enable only when needed IORDY
  - use dev_get_drvdata
v3:
  - add missing clk_put() calls
  - use platform_get_irq()
  - fix resume code to avoid disabling IORDY on resume
v4:
  - Remove EXPERIMENTAL and switch to depends on ARCH_MXC
  - Use devm_kzalloc()
  - make clock a must-have
  - Use only 1 ioremap

Signed-off-by: Arnaud Patard <arnaud.patard@rtp-net.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

drivers/ata/Kconfig
drivers/ata/Makefile
drivers/ata/pata_imx.c [new file with mode: 0644]

index ca3e6be..5987e0b 100644 (file)
@@ -468,6 +468,15 @@ config PATA_ICSIDE
          interface card.  This is not required for ICS partition support.
          If you are unsure, say N to this.
 
+config PATA_IMX
+       tristate "PATA support for Freescale iMX"
+       depends on ARCH_MXC
+       help
+         This option enables support for the PATA host available on Freescale
+          iMX SoCs.
+
+         If unsure, say N.
+
 config PATA_IT8213
        tristate "IT8213 PATA support (Experimental)"
        depends on PCI && EXPERIMENTAL
index 8ac64e1..9550d69 100644 (file)
@@ -48,6 +48,7 @@ obj-$(CONFIG_PATA_HPT37X)     += pata_hpt37x.o
 obj-$(CONFIG_PATA_HPT3X2N)     += pata_hpt3x2n.o
 obj-$(CONFIG_PATA_HPT3X3)      += pata_hpt3x3.o
 obj-$(CONFIG_PATA_ICSIDE)      += pata_icside.o
+obj-$(CONFIG_PATA_IMX)         += pata_imx.o
 obj-$(CONFIG_PATA_IT8213)      += pata_it8213.o
 obj-$(CONFIG_PATA_IT821X)      += pata_it821x.o
 obj-$(CONFIG_PATA_JMICRON)     += pata_jmicron.o
diff --git a/drivers/ata/pata_imx.c b/drivers/ata/pata_imx.c
new file mode 100644 (file)
index 0000000..ca9d9ca
--- /dev/null
@@ -0,0 +1,253 @@
+/*
+ * Freescale iMX PATA driver
+ *
+ * Copyright (C) 2011 Arnaud Patard <arnaud.patard@rtp-net.org>
+ *
+ * Based on pata_platform - Copyright (C) 2006 - 2007  Paul Mundt
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * TODO:
+ * - dmaengine support
+ * - check if timing stuff needed
+ */
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/blkdev.h>
+#include <scsi/scsi_host.h>
+#include <linux/ata.h>
+#include <linux/libata.h>
+#include <linux/platform_device.h>
+#include <linux/clk.h>
+
+#define DRV_NAME "pata_imx"
+
+#define PATA_IMX_ATA_CONTROL           0x24
+#define PATA_IMX_ATA_CTRL_FIFO_RST_B   (1<<7)
+#define PATA_IMX_ATA_CTRL_ATA_RST_B    (1<<6)
+#define PATA_IMX_ATA_CTRL_IORDY_EN     (1<<0)
+#define PATA_IMX_ATA_INT_EN            0x2C
+#define PATA_IMX_ATA_INTR_ATA_INTRQ2   (1<<3)
+#define PATA_IMX_DRIVE_DATA            0xA0
+#define PATA_IMX_DRIVE_CONTROL         0xD8
+
+struct pata_imx_priv {
+       struct clk *clk;
+       /* timings/interrupt/control regs */
+       u8 *host_regs;
+       u32 ata_ctl;
+};
+
+static int pata_imx_set_mode(struct ata_link *link, struct ata_device **unused)
+{
+       struct ata_device *dev;
+       struct ata_port *ap = link->ap;
+       struct pata_imx_priv *priv = ap->host->private_data;
+       u32 val;
+
+       ata_for_each_dev(dev, link, ENABLED) {
+               dev->pio_mode = dev->xfer_mode = XFER_PIO_0;
+               dev->xfer_shift = ATA_SHIFT_PIO;
+               dev->flags |= ATA_DFLAG_PIO;
+
+               val = __raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
+               if (ata_pio_need_iordy(dev))
+                       val |= PATA_IMX_ATA_CTRL_IORDY_EN;
+               else
+                       val &= ~PATA_IMX_ATA_CTRL_IORDY_EN;
+               __raw_writel(val, priv->host_regs + PATA_IMX_ATA_CONTROL);
+
+               ata_dev_printk(dev, KERN_INFO, "configured for PIO\n");
+       }
+       return 0;
+}
+
+static struct scsi_host_template pata_imx_sht = {
+       ATA_PIO_SHT(DRV_NAME),
+};
+
+static struct ata_port_operations pata_imx_port_ops = {
+       .inherits               = &ata_sff_port_ops,
+       .sff_data_xfer          = ata_sff_data_xfer_noirq,
+       .cable_detect           = ata_cable_unknown,
+       .set_mode               = pata_imx_set_mode,
+};
+
+static void pata_imx_setup_port(struct ata_ioports *ioaddr)
+{
+       /* Fixup the port shift for platforms that need it */
+       ioaddr->data_addr       = ioaddr->cmd_addr + (ATA_REG_DATA    << 2);
+       ioaddr->error_addr      = ioaddr->cmd_addr + (ATA_REG_ERR     << 2);
+       ioaddr->feature_addr    = ioaddr->cmd_addr + (ATA_REG_FEATURE << 2);
+       ioaddr->nsect_addr      = ioaddr->cmd_addr + (ATA_REG_NSECT   << 2);
+       ioaddr->lbal_addr       = ioaddr->cmd_addr + (ATA_REG_LBAL    << 2);
+       ioaddr->lbam_addr       = ioaddr->cmd_addr + (ATA_REG_LBAM    << 2);
+       ioaddr->lbah_addr       = ioaddr->cmd_addr + (ATA_REG_LBAH    << 2);
+       ioaddr->device_addr     = ioaddr->cmd_addr + (ATA_REG_DEVICE  << 2);
+       ioaddr->status_addr     = ioaddr->cmd_addr + (ATA_REG_STATUS  << 2);
+       ioaddr->command_addr    = ioaddr->cmd_addr + (ATA_REG_CMD     << 2);
+}
+
+static int __devinit pata_imx_probe(struct platform_device *pdev)
+{
+       struct ata_host *host;
+       struct ata_port *ap;
+       struct pata_imx_priv *priv;
+       int irq = 0;
+       struct resource *io_res;
+
+       io_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (io_res == NULL)
+               return -EINVAL;
+
+       irq = platform_get_irq(pdev, 0);
+       if (irq <= 0)
+               return -EINVAL;
+
+       priv = devm_kzalloc(&pdev->dev,
+                               sizeof(struct pata_imx_priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       priv->clk = clk_get(&pdev->dev, NULL);
+       if (IS_ERR(priv->clk)) {
+               dev_err(&pdev->dev, "Failed to get clock\n");
+               return PTR_ERR(priv->clk);
+       }
+
+       clk_enable(priv->clk);
+
+       host = ata_host_alloc(&pdev->dev, 1);
+       if (!host)
+               goto free_priv;
+
+       host->private_data = priv;
+       ap = host->ports[0];
+
+       ap->ops = &pata_imx_port_ops;
+       ap->pio_mask = ATA_PIO0;
+       ap->flags |= ATA_FLAG_SLAVE_POSS;
+
+       priv->host_regs = devm_ioremap(&pdev->dev, io_res->start,
+               resource_size(io_res));
+       if (!priv->host_regs) {
+               dev_err(&pdev->dev, "failed to map IO/CTL base\n");
+               goto free_priv;
+       }
+
+       ap->ioaddr.cmd_addr = priv->host_regs + PATA_IMX_DRIVE_DATA;
+       ap->ioaddr.ctl_addr = priv->host_regs + PATA_IMX_DRIVE_CONTROL;
+
+       ap->ioaddr.altstatus_addr = ap->ioaddr.ctl_addr;
+
+       pata_imx_setup_port(&ap->ioaddr);
+
+       ata_port_desc(ap, "cmd 0x%llx ctl 0x%llx",
+               (unsigned long long)io_res->start + PATA_IMX_DRIVE_DATA,
+               (unsigned long long)io_res->start + PATA_IMX_DRIVE_CONTROL);
+
+       /* deassert resets */
+       __raw_writel(PATA_IMX_ATA_CTRL_FIFO_RST_B |
+                       PATA_IMX_ATA_CTRL_ATA_RST_B,
+                       priv->host_regs + PATA_IMX_ATA_CONTROL);
+       /* enable interrupts */
+       __raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
+                       priv->host_regs + PATA_IMX_ATA_INT_EN);
+
+       /* activate */
+       return ata_host_activate(host, irq, ata_sff_interrupt, 0,
+                               &pata_imx_sht);
+
+free_priv:
+       clk_disable(priv->clk);
+       clk_put(priv->clk);
+       return -ENOMEM;
+}
+
+static int __devexit pata_imx_remove(struct platform_device *pdev)
+{
+       struct ata_host *host = dev_get_drvdata(&pdev->dev);
+       struct pata_imx_priv *priv = host->private_data;
+
+       ata_host_detach(host);
+
+       __raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
+
+       clk_disable(priv->clk);
+       clk_put(priv->clk);
+
+       return 0;
+}
+
+#ifdef CONFIG_PM
+static int pata_imx_suspend(struct device *dev)
+{
+       struct ata_host *host = dev_get_drvdata(dev);
+       struct pata_imx_priv *priv = host->private_data;
+       int ret;
+
+       ret = ata_host_suspend(host, PMSG_SUSPEND);
+       if (!ret) {
+               __raw_writel(0, priv->host_regs + PATA_IMX_ATA_INT_EN);
+               priv->ata_ctl =
+                       __raw_readl(priv->host_regs + PATA_IMX_ATA_CONTROL);
+               clk_disable(priv->clk);
+       }
+
+       return ret;
+}
+
+static int pata_imx_resume(struct device *dev)
+{
+       struct ata_host *host = dev_get_drvdata(dev);
+       struct pata_imx_priv *priv = host->private_data;
+
+       clk_enable(priv->clk);
+
+       __raw_writel(priv->ata_ctl, priv->host_regs + PATA_IMX_ATA_CONTROL);
+
+       __raw_writel(PATA_IMX_ATA_INTR_ATA_INTRQ2,
+                       priv->host_regs + PATA_IMX_ATA_INT_EN);
+
+       ata_host_resume(host);
+
+       return 0;
+}
+
+static const struct dev_pm_ops pata_imx_pm_ops = {
+       .suspend        = pata_imx_suspend,
+       .resume         = pata_imx_resume,
+};
+#endif
+
+static struct platform_driver pata_imx_driver = {
+       .probe          = pata_imx_probe,
+       .remove         = __devexit_p(pata_imx_remove),
+       .driver = {
+               .name           = DRV_NAME,
+               .owner          = THIS_MODULE,
+#ifdef CONFIG_PM
+               .pm             = &pata_imx_pm_ops,
+#endif
+       },
+};
+
+static int __init pata_imx_init(void)
+{
+       return platform_driver_register(&pata_imx_driver);
+}
+
+static void __exit pata_imx_exit(void)
+{
+       platform_driver_unregister(&pata_imx_driver);
+}
+module_init(pata_imx_init);
+module_exit(pata_imx_exit);
+
+MODULE_AUTHOR("Arnaud Patard <arnaud.patard@rtp-net.org>");
+MODULE_DESCRIPTION("low-level driver for iMX PATA");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:" DRV_NAME);