tx4938ide.c

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/*
 * TX4938 internal IDE driver
 * Based on tx4939ide.c.
 *
 * 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.
 *
 * (C) Copyright TOSHIBA CORPORATION 2005-2007
 */

#include <linux/module.h>
#include <linux/types.h>
#include <linux/ide.h>
#include <linux/init.h>
#include <linux/platform_device.h>
#include <linux/io.h>

#include <asm/ide.h>
#include <asm/txx9/tx4938.h>

static void tx4938ide_tune_ebusc(unsigned int ebus_ch,
                 unsigned int gbus_clock,
                 u8 pio)
{
    struct ide_timing *t = ide_timing_find_mode(XFER_PIO_0 + pio);
    u64 cr = __raw_readq(&tx4938_ebuscptr->cr[ebus_ch]);
    unsigned int sp = (cr >> 4) & 3;
    unsigned int clock = gbus_clock / (4 - sp);
    unsigned int cycle = 1000000000 / clock;
    unsigned int shwt;
    int wt;

    /* Minimum DIOx- active time */
    wt = DIV_ROUND_UP(t->act8b, cycle) - 2;
    /* IORDY setup time: 35ns */
    wt = max_t(int, wt, DIV_ROUND_UP(35, cycle));
    /* actual wait-cycle is max(wt & ~1, 1) */
    if (wt > 2 && (wt & 1))
        wt++;
    wt &= ~1;
    /* Address-valid to DIOR/DIOW setup */
    shwt = DIV_ROUND_UP(t->setup, cycle);

    /* -DIOx recovery time (SHWT * 4) and cycle time requirement */
    while ((shwt * 4 + wt + (wt ? 2 : 3)) * cycle < t->cycle)
        shwt++;
    if (shwt > 7) {
        pr_warning("tx4938ide: SHWT violation (%d)\n", shwt);
        shwt = 7;
    }
    pr_debug("tx4938ide: ebus %d, bus cycle %dns, WT %d, SHWT %d\n",
         ebus_ch, cycle, wt, shwt);

    __raw_writeq((cr & ~0x3f007ull) | (wt << 12) | shwt,
             &tx4938_ebuscptr->cr[ebus_ch]);
}

static void tx4938ide_set_pio_mode(ide_hwif_t *hwif, ide_drive_t *drive)
{
    struct tx4938ide_platform_info *pdata = hwif->dev->platform_data;
    u8 safe = drive->pio_mode - XFER_PIO_0;
    ide_drive_t *pair;

    pair = ide_get_pair_dev(drive);
    if (pair)
        safe = min_t(u8, safe, pair->pio_mode - XFER_PIO_0);
    tx4938ide_tune_ebusc(pdata->ebus_ch, pdata->gbus_clock, safe);
}

#ifdef __BIG_ENDIAN

/* custom iops (independent from SWAP_IO_SPACE) */
static void tx4938ide_input_data_swap(ide_drive_t *drive, struct ide_cmd *cmd,
                void *buf, unsigned int len)
{
    unsigned long port = drive->hwif->io_ports.data_addr;
    unsigned short *ptr = buf;
    unsigned int count = (len + 1) / 2;

    while (count--)
        *ptr++ = cpu_to_le16(__raw_readw((void __iomem *)port));
    __ide_flush_dcache_range((unsigned long)buf, roundup(len, 2));
}

static void tx4938ide_output_data_swap(ide_drive_t *drive, struct ide_cmd *cmd,
                void *buf, unsigned int len)
{
    unsigned long port = drive->hwif->io_ports.data_addr;
    unsigned short *ptr = buf;
    unsigned int count = (len + 1) / 2;

    while (count--) {
        __raw_writew(le16_to_cpu(*ptr), (void __iomem *)port);
        ptr++;
    }
    __ide_flush_dcache_range((unsigned long)buf, roundup(len, 2));
}

static const struct ide_tp_ops tx4938ide_tp_ops = {
    .exec_command       = ide_exec_command,
    .read_status        = ide_read_status,
    .read_altstatus     = ide_read_altstatus,
    .write_devctl       = ide_write_devctl,

    .dev_select     = ide_dev_select,
    .tf_load        = ide_tf_load,
    .tf_read        = ide_tf_read,

    .input_data     = tx4938ide_input_data_swap,
    .output_data        = tx4938ide_output_data_swap,
};

#endif  /* __BIG_ENDIAN */

static const struct ide_port_ops tx4938ide_port_ops = {
    .set_pio_mode       = tx4938ide_set_pio_mode,
};

static const struct ide_port_info tx4938ide_port_info __initconst = {
    .port_ops       = &tx4938ide_port_ops,
#ifdef __BIG_ENDIAN
    .tp_ops         = &tx4938ide_tp_ops,
#endif
    .host_flags     = IDE_HFLAG_MMIO | IDE_HFLAG_NO_DMA,
    .pio_mask       = ATA_PIO5,
    .chipset        = ide_generic,
};

static int __init tx4938ide_probe(struct platform_device *pdev)
{
    struct ide_hw hw, *hws[] = { &hw };
    struct ide_host *host;
    struct resource *res;
    struct tx4938ide_platform_info *pdata = pdev->dev.platform_data;
    int irq, ret, i;
    unsigned long mapbase, mapctl;
    struct ide_port_info d = tx4938ide_port_info;

    irq = platform_get_irq(pdev, 0);
    if (irq < 0)
        return -ENODEV;
    res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
    if (!res)
        return -ENODEV;

    if (!devm_request_mem_region(&pdev->dev, res->start,
                     resource_size(res), "tx4938ide"))
        return -EBUSY;
    mapbase = (unsigned long)devm_ioremap(&pdev->dev, res->start,
                          8 << pdata->ioport_shift);
    mapctl = (unsigned long)devm_ioremap(&pdev->dev,
                         res->start + 0x10000 +
                         (6 << pdata->ioport_shift),
                         1 << pdata->ioport_shift);
    if (!mapbase || !mapctl)
        return -EBUSY;

    memset(&hw, 0, sizeof(hw));
    if (pdata->ioport_shift) {
        unsigned long port = mapbase;
        unsigned long ctl = mapctl;

        hw.io_ports_array[0] = port;
#ifdef __BIG_ENDIAN
        port++;
        ctl++;
#endif
        for (i = 1; i <= 7; i++)
            hw.io_ports_array[i] =
                port + (i << pdata->ioport_shift);
        hw.io_ports.ctl_addr = ctl;
    } else
        ide_std_init_ports(&hw, mapbase, mapctl);
    hw.irq = irq;
    hw.dev = &pdev->dev;

    pr_info("TX4938 IDE interface (base %#lx, ctl %#lx, irq %d)\n",
        mapbase, mapctl, hw.irq);
    if (pdata->gbus_clock)
        tx4938ide_tune_ebusc(pdata->ebus_ch, pdata->gbus_clock, 0);
    else
        d.port_ops = NULL;
    ret = ide_host_add(&d, hws, 1, &host);
    if (!ret)
        platform_set_drvdata(pdev, host);
    return ret;
}

static int __exit tx4938ide_remove(struct platform_device *pdev)
{
    struct ide_host *host = platform_get_drvdata(pdev);

    ide_host_remove(host);
    return 0;
}

static struct platform_driver tx4938ide_driver = {
    .driver     = {
        .name   = "tx4938ide",
        .owner  = THIS_MODULE,
    },
    .remove = __exit_p(tx4938ide_remove),
};

static int __init tx4938ide_init(void)
{
    return platform_driver_probe(&tx4938ide_driver, tx4938ide_probe);
}

static void __exit tx4938ide_exit(void)
{
    platform_driver_unregister(&tx4938ide_driver);
}

module_init(tx4938ide_init);
module_exit(tx4938ide_exit);

MODULE_DESCRIPTION("TX4938 internal IDE driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:tx4938ide");