linux-imx

/*

 * 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 = dev_get_platdata(hwif->dev);

    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;

​