ahci_platform.c

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/*
 * AHCI SATA platform driver
 *
 * Copyright 2004-2005  Red Hat, Inc.
 *   Jeff Garzik <[email protected]>
 * Copyright 2010  MontaVista Software, LLC.
 *   Anton Vorontsov <[email protected]>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2, or (at your option)
 * any later version.
 */

#include <linux/clk.h>
#include <linux/kernel.h>
#include <linux/gfp.h>
#include <linux/module.h>
#include <linux/pm.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/libata.h>
#include <linux/ahci_platform.h>
#include "ahci.h"

enum ahci_type {
    AHCI,       /* standard platform ahci */
    IMX53_AHCI, /* ahci on i.mx53 */
    STRICT_AHCI,    /* delayed DMA engine start */
};

static struct platform_device_id ahci_devtype[] = {
    {
        .name = "ahci",
        .driver_data = AHCI,
    }, {
        .name = "imx53-ahci",
        .driver_data = IMX53_AHCI,
    }, {
        .name = "strict-ahci",
        .driver_data = STRICT_AHCI,
    }, {
        /* sentinel */
    }
};
MODULE_DEVICE_TABLE(platform, ahci_devtype);


static const struct ata_port_info ahci_port_info[] = {
    /* by features */
    [AHCI] = {
        .flags      = AHCI_FLAG_COMMON,
        .pio_mask   = ATA_PIO4,
        .udma_mask  = ATA_UDMA6,
        .port_ops   = &ahci_ops,
    },
    [IMX53_AHCI] = {
        .flags      = AHCI_FLAG_COMMON,
        .pio_mask   = ATA_PIO4,
        .udma_mask  = ATA_UDMA6,
        .port_ops   = &ahci_pmp_retry_srst_ops,
    },
    [STRICT_AHCI] = {
        AHCI_HFLAGS (AHCI_HFLAG_DELAY_ENGINE),
        .flags      = AHCI_FLAG_COMMON,
        .pio_mask   = ATA_PIO4,
        .udma_mask  = ATA_UDMA6,
        .port_ops   = &ahci_ops,
    },
};

static struct scsi_host_template ahci_platform_sht = {
    AHCI_SHT("ahci_platform"),
};

static int __init ahci_probe(struct platform_device *pdev)
{
    struct device *dev = &pdev->dev;
    struct ahci_platform_data *pdata = dev_get_platdata(dev);
    const struct platform_device_id *id = platform_get_device_id(pdev);
    struct ata_port_info pi = ahci_port_info[id ? id->driver_data : 0];
    const struct ata_port_info *ppi[] = { &pi, NULL };
    struct ahci_host_priv *hpriv;
    struct ata_host *host;
    struct resource *mem;
    int irq;
    int n_ports;
    int i;
    int rc;

    mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!mem) {
        dev_err(dev, "no mmio space\n");
        return -EINVAL;
    }

    irq = platform_get_irq(pdev, 0);
    if (irq <= 0) {
        dev_err(dev, "no irq\n");
        return -EINVAL;
    }

    if (pdata && pdata->ata_port_info)
        pi = *pdata->ata_port_info;

    hpriv = devm_kzalloc(dev, sizeof(*hpriv), GFP_KERNEL);
    if (!hpriv) {
        dev_err(dev, "can't alloc ahci_host_priv\n");
        return -ENOMEM;
    }

    hpriv->flags |= (unsigned long)pi.private_data;

    hpriv->mmio = devm_ioremap(dev, mem->start, resource_size(mem));
    if (!hpriv->mmio) {
        dev_err(dev, "can't map %pR\n", mem);
        return -ENOMEM;
    }

    hpriv->clk = clk_get(dev, NULL);
    if (IS_ERR(hpriv->clk)) {
        dev_err(dev, "can't get clock\n");
    } else {
        rc = clk_prepare_enable(hpriv->clk);
        if (rc) {
            dev_err(dev, "clock prepare enable failed");
            goto free_clk;
        }
    }

    /*
     * Some platforms might need to prepare for mmio region access,
     * which could be done in the following init call. So, the mmio
     * region shouldn't be accessed before init (if provided) has
     * returned successfully.
     */
    if (pdata && pdata->init) {
        rc = pdata->init(dev, hpriv->mmio);
        if (rc)
            goto disable_unprepare_clk;
    }

    ahci_save_initial_config(dev, hpriv,
        pdata ? pdata->force_port_map : 0,
        pdata ? pdata->mask_port_map  : 0);

    /* prepare host */
    if (hpriv->cap & HOST_CAP_NCQ)
        pi.flags |= ATA_FLAG_NCQ;

    if (hpriv->cap & HOST_CAP_PMP)
        pi.flags |= ATA_FLAG_PMP;

    ahci_set_em_messages(hpriv, &pi);

    /* CAP.NP sometimes indicate the index of the last enabled
     * port, at other times, that of the last possible port, so
     * determining the maximum port number requires looking at
     * both CAP.NP and port_map.
     */
    n_ports = max(ahci_nr_ports(hpriv->cap), fls(hpriv->port_map));

    host = ata_host_alloc_pinfo(dev, ppi, n_ports);
    if (!host) {
        rc = -ENOMEM;
        goto pdata_exit;
    }

    host->private_data = hpriv;

    if (!(hpriv->cap & HOST_CAP_SSS) || ahci_ignore_sss)
        host->flags |= ATA_HOST_PARALLEL_SCAN;
    else
        printk(KERN_INFO "ahci: SSS flag set, parallel bus scan disabled\n");

    if (pi.flags & ATA_FLAG_EM)
        ahci_reset_em(host);

    for (i = 0; i < host->n_ports; i++) {
        struct ata_port *ap = host->ports[i];

        ata_port_desc(ap, "mmio %pR", mem);
        ata_port_desc(ap, "port 0x%x", 0x100 + ap->port_no * 0x80);

        /* set enclosure management message type */
        if (ap->flags & ATA_FLAG_EM)
            ap->em_message_type = hpriv->em_msg_type;

        /* disabled/not-implemented port */
        if (!(hpriv->port_map & (1 << i)))
            ap->ops = &ata_dummy_port_ops;
    }

    rc = ahci_reset_controller(host);
    if (rc)
        goto pdata_exit;

    ahci_init_controller(host);
    ahci_print_info(host, "platform");

    rc = ata_host_activate(host, irq, ahci_interrupt, IRQF_SHARED,
                   &ahci_platform_sht);
    if (rc)
        goto pdata_exit;

    return 0;
pdata_exit:
    if (pdata && pdata->exit)
        pdata->exit(dev);
disable_unprepare_clk:
    if (!IS_ERR(hpriv->clk))
        clk_disable_unprepare(hpriv->clk);
free_clk:
    if (!IS_ERR(hpriv->clk))
        clk_put(hpriv->clk);
    return rc;
}

static int __devexit ahci_remove(struct platform_device *pdev)
{
    struct device *dev = &pdev->dev;
    struct ahci_platform_data *pdata = dev_get_platdata(dev);
    struct ata_host *host = dev_get_drvdata(dev);
    struct ahci_host_priv *hpriv = host->private_data;

    ata_host_detach(host);

    if (pdata && pdata->exit)
        pdata->exit(dev);

    if (!IS_ERR(hpriv->clk)) {
        clk_disable_unprepare(hpriv->clk);
        clk_put(hpriv->clk);
    }

    return 0;
}

#ifdef CONFIG_PM_SLEEP
static int ahci_suspend(struct device *dev)
{
    struct ahci_platform_data *pdata = dev_get_platdata(dev);
    struct ata_host *host = dev_get_drvdata(dev);
    struct ahci_host_priv *hpriv = host->private_data;
    void __iomem *mmio = hpriv->mmio;
    u32 ctl;
    int rc;

    if (hpriv->flags & AHCI_HFLAG_NO_SUSPEND) {
        dev_err(dev, "firmware update required for suspend/resume\n");
        return -EIO;
    }

    /*
     * AHCI spec rev1.1 section 8.3.3:
     * Software must disable interrupts prior to requesting a
     * transition of the HBA to D3 state.
     */
    ctl = readl(mmio + HOST_CTL);
    ctl &= ~HOST_IRQ_EN;
    writel(ctl, mmio + HOST_CTL);
    readl(mmio + HOST_CTL); /* flush */

    rc = ata_host_suspend(host, PMSG_SUSPEND);
    if (rc)
        return rc;

    if (pdata && pdata->suspend)
        return pdata->suspend(dev);

    if (!IS_ERR(hpriv->clk))
        clk_disable_unprepare(hpriv->clk);

    return 0;
}

static int ahci_resume(struct device *dev)
{
    struct ahci_platform_data *pdata = dev_get_platdata(dev);
    struct ata_host *host = dev_get_drvdata(dev);
    struct ahci_host_priv *hpriv = host->private_data;
    int rc;

    if (!IS_ERR(hpriv->clk)) {
        rc = clk_prepare_enable(hpriv->clk);
        if (rc) {
            dev_err(dev, "clock prepare enable failed");
            return rc;
        }
    }

    if (pdata && pdata->resume) {
        rc = pdata->resume(dev);
        if (rc)
            goto disable_unprepare_clk;
    }

    if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
        rc = ahci_reset_controller(host);
        if (rc)
            goto disable_unprepare_clk;

        ahci_init_controller(host);
    }

    ata_host_resume(host);

    return 0;

disable_unprepare_clk:
    if (!IS_ERR(hpriv->clk))
        clk_disable_unprepare(hpriv->clk);

    return rc;
}
#endif

SIMPLE_DEV_PM_OPS(ahci_pm_ops, ahci_suspend, ahci_resume);

static const struct of_device_id ahci_of_match[] = {
    { .compatible = "snps,spear-ahci", },
    {},
};
MODULE_DEVICE_TABLE(of, ahci_of_match);

static struct platform_driver ahci_driver = {
    .remove = __devexit_p(ahci_remove),
    .driver = {
        .name = "ahci",
        .owner = THIS_MODULE,
        .of_match_table = ahci_of_match,
        .pm = &ahci_pm_ops,
    },
    .id_table   = ahci_devtype,
};

static int __init ahci_init(void)
{
    return platform_driver_probe(&ahci_driver, ahci_probe);
}
module_init(ahci_init);

static void __exit ahci_exit(void)
{
    platform_driver_unregister(&ahci_driver);
}
module_exit(ahci_exit);

MODULE_DESCRIPTION("AHCI SATA platform driver");
MODULE_AUTHOR("Anton Vorontsov <[email protected]>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:ahci");