ide: Add tx4939ide driver (v6)

This is the driver for the Toshiba TX4939 SoC ATA controller.

This controller has standard ATA taskfile registers and DMA
command/status registers, but the register layout is swapped on big
endian.  There are some other endian issue and some special registers
which requires many custom dma_ops/tp_ops routines and build_dmatable.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Acked-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: ralf@linux-mips.org
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

3 files changed, 761 insertions, 0 deletions

diff --git a/drivers/ide/Kconfig b/drivers/ide/Kconfig
index a820ca6fc327..4e88c72cee42 100644
--- a/drivers/ide/Kconfig
+++ b/drivers/ide/Kconfig
@@ -720,6 +720,11 @@ config BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ
        default "128"
        depends on BLK_DEV_IDE_AU1XXX
 
+config BLK_DEV_IDE_TX4939
+        tristate "TX4939 internal IDE support"
+        depends on SOC_TX4939
+        select BLK_DEV_IDEDMA_SFF
+
 config IDE_ARM
         tristate "ARM IDE support"
         depends on ARM && (ARCH_CLPS7500 || ARCH_RPC || ARCH_SHARK)
diff --git a/drivers/ide/Makefile b/drivers/ide/Makefile
index 9cf92ac939d2..b1680dc1d040 100644
--- a/drivers/ide/Makefile
+++ b/drivers/ide/Makefile
@@ -111,3 +111,5 @@ obj-$(CONFIG_BLK_DEV_IDE_RAPIDE)	+= rapide.o
 obj-$(CONFIG_BLK_DEV_PALMCHIP_BK3710)   += palm_bk3710.o
 
 obj-$(CONFIG_BLK_DEV_IDE_AU1XXX)        += au1xxx-ide.o
+
+obj-$(CONFIG_BLK_DEV_IDE_TX4939)        += tx4939ide.o
diff --git a/drivers/ide/tx4939ide.c b/drivers/ide/tx4939ide.c
new file mode 100644
index 000000000000..bafb7d1a22e2
--- /dev/null
+++ b/drivers/ide/tx4939ide.c
@@ -0,0 +1,754 @@
+/*
+ * TX4939 internal IDE driver
+ * Based on RBTX49xx patch from CELF patch archive.
+ *
+ * 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/delay.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/scatterlist.h>
+
+#define MODNAME "tx4939ide"
+
+/* ATA Shadow Registers (8-bit except for Data which is 16-bit) */
+#define TX4939IDE_Data                  0x000
+#define TX4939IDE_Error_Feature         0x001
+#define TX4939IDE_Sec                   0x002
+#define TX4939IDE_LBA0                  0x003
+#define TX4939IDE_LBA1                  0x004
+#define TX4939IDE_LBA2                  0x005
+#define TX4939IDE_DevHead               0x006
+#define TX4939IDE_Stat_Cmd              0x007
+#define TX4939IDE_AltStat_DevCtl        0x402
+/* H/W DMA Registers  */
+#define TX4939IDE_DMA_Cmd       0x800   /* 8-bit */
+#define TX4939IDE_DMA_Stat      0x802   /* 8-bit */
+#define TX4939IDE_PRD_Ptr       0x804   /* 32-bit */
+/* ATA100 CORE Registers (16-bit) */
+#define TX4939IDE_Sys_Ctl       0xc00
+#define TX4939IDE_Xfer_Cnt_1    0xc08
+#define TX4939IDE_Xfer_Cnt_2    0xc0a
+#define TX4939IDE_Sec_Cnt       0xc10
+#define TX4939IDE_Start_Lo_Addr 0xc18
+#define TX4939IDE_Start_Up_Addr 0xc20
+#define TX4939IDE_Add_Ctl       0xc28
+#define TX4939IDE_Lo_Burst_Cnt  0xc30
+#define TX4939IDE_Up_Burst_Cnt  0xc38
+#define TX4939IDE_PIO_Addr      0xc88
+#define TX4939IDE_H_Rst_Tim     0xc90
+#define TX4939IDE_Int_Ctl       0xc98
+#define TX4939IDE_Pkt_Cmd       0xcb8
+#define TX4939IDE_Bxfer_Cnt_Hi  0xcc0
+#define TX4939IDE_Bxfer_Cnt_Lo  0xcc8
+#define TX4939IDE_Dev_TErr      0xcd0
+#define TX4939IDE_Pkt_Xfer_Ctl  0xcd8
+#define TX4939IDE_Start_TAddr   0xce0
+
+/* bits for Int_Ctl */
+#define TX4939IDE_INT_ADDRERR   0x80
+#define TX4939IDE_INT_REACHMUL  0x40
+#define TX4939IDE_INT_DEVTIMING 0x20
+#define TX4939IDE_INT_UDMATERM  0x10
+#define TX4939IDE_INT_TIMER     0x08
+#define TX4939IDE_INT_BUSERR    0x04
+#define TX4939IDE_INT_XFEREND   0x02
+#define TX4939IDE_INT_HOST      0x01
+
+#define TX4939IDE_IGNORE_INTS   \
+        (TX4939IDE_INT_ADDRERR | TX4939IDE_INT_REACHMUL | \
+         TX4939IDE_INT_DEVTIMING | TX4939IDE_INT_UDMATERM | \
+         TX4939IDE_INT_TIMER | TX4939IDE_INT_XFEREND)
+
+#ifdef __BIG_ENDIAN
+#define tx4939ide_swizzlel(a)   ((a) ^ 4)
+#define tx4939ide_swizzlew(a)   ((a) ^ 6)
+#define tx4939ide_swizzleb(a)   ((a) ^ 7)
+#else
+#define tx4939ide_swizzlel(a)   (a)
+#define tx4939ide_swizzlew(a)   (a)
+#define tx4939ide_swizzleb(a)   (a)
+#endif
+
+static u16 tx4939ide_readw(void __iomem *base, u32 reg)
+{
+        return __raw_readw(base + tx4939ide_swizzlew(reg));
+}
+static u8 tx4939ide_readb(void __iomem *base, u32 reg)
+{
+        return __raw_readb(base + tx4939ide_swizzleb(reg));
+}
+static void tx4939ide_writel(u32 val, void __iomem *base, u32 reg)
+{
+        __raw_writel(val, base + tx4939ide_swizzlel(reg));
+}
+static void tx4939ide_writew(u16 val, void __iomem *base, u32 reg)
+{
+        __raw_writew(val, base + tx4939ide_swizzlew(reg));
+}
+static void tx4939ide_writeb(u8 val, void __iomem *base, u32 reg)
+{
+        __raw_writeb(val, base + tx4939ide_swizzleb(reg));
+}
+
+#define TX4939IDE_BASE(hwif)    ((void __iomem *)(hwif)->extra_base)
+
+static void tx4939ide_set_pio_mode(ide_drive_t *drive, const u8 pio)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        int is_slave = drive->dn;
+        u32 mask, val;
+        u8 safe = pio;
+        ide_drive_t *pair;
+
+        pair = ide_get_pair_dev(drive);
+        if (pair)
+                safe = min(safe, ide_get_best_pio_mode(pair, 255, 4));
+        /*
+         * Update Command Transfer Mode for master/slave and Data
+         * Transfer Mode for this drive.
+         */
+        mask = is_slave ? 0x07f00000 : 0x000007f0;
+        val = ((safe << 8) | (pio << 4)) << (is_slave ? 16 : 0);
+        hwif->select_data = (hwif->select_data & ~mask) | val;
+        /* tx4939ide_tf_load_fixup() will set the Sys_Ctl register */
+}
+
+static void tx4939ide_set_dma_mode(ide_drive_t *drive, const u8 mode)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        u32 mask, val;
+
+        /* Update Data Transfer Mode for this drive. */
+        if (mode >= XFER_UDMA_0)
+                val = mode - XFER_UDMA_0 + 8;
+        else
+                val = mode - XFER_MW_DMA_0 + 5;
+        if (drive->dn) {
+                mask = 0x00f00000;
+                val <<= 20;
+        } else {
+                mask = 0x000000f0;
+                val <<= 4;
+        }
+        hwif->select_data = (hwif->select_data & ~mask) | val;
+        /* tx4939ide_tf_load_fixup() will set the Sys_Ctl register */
+}
+
+static u16 tx4939ide_check_error_ints(ide_hwif_t *hwif)
+{
+        void __iomem *base = TX4939IDE_BASE(hwif);
+        u16 ctl = tx4939ide_readw(base, TX4939IDE_Int_Ctl);
+
+        if (ctl & TX4939IDE_INT_BUSERR) {
+                /* reset FIFO */
+                u16 sysctl = tx4939ide_readw(base, TX4939IDE_Sys_Ctl);
+
+                tx4939ide_writew(sysctl | 0x4000, base, TX4939IDE_Sys_Ctl);
+                mmiowb();
+                /* wait 12GBUSCLK (typ. 60ns @ GBUS200MHz, max 270ns) */
+                ndelay(270);
+                tx4939ide_writew(sysctl, base, TX4939IDE_Sys_Ctl);
+        }
+        if (ctl & (TX4939IDE_INT_ADDRERR |
+                   TX4939IDE_INT_DEVTIMING | TX4939IDE_INT_BUSERR))
+                pr_err("%s: Error interrupt %#x (%s%s%s )\n",
+                       hwif->name, ctl,
+                       ctl & TX4939IDE_INT_ADDRERR ? " Address-Error" : "",
+                       ctl & TX4939IDE_INT_DEVTIMING ? " DEV-Timing" : "",
+                       ctl & TX4939IDE_INT_BUSERR ? " Bus-Error" : "");
+        return ctl;
+}
+
+static void tx4939ide_clear_irq(ide_drive_t *drive)
+{
+        ide_hwif_t *hwif;
+        void __iomem *base;
+        u16 ctl;
+
+        /*
+         * tx4939ide_dma_test_irq() and tx4939ide_dma_end() do all job
+         * for DMA case.
+         */
+        if (drive->waiting_for_dma)
+                return;
+        hwif = drive->hwif;
+        base = TX4939IDE_BASE(hwif);
+        ctl = tx4939ide_check_error_ints(hwif);
+        tx4939ide_writew(ctl, base, TX4939IDE_Int_Ctl);
+}
+
+static u8 tx4939ide_cable_detect(ide_hwif_t *hwif)
+{
+        void __iomem *base = TX4939IDE_BASE(hwif);
+
+        return tx4939ide_readw(base, TX4939IDE_Sys_Ctl) & 0x2000 ?
+                ATA_CBL_PATA40 : ATA_CBL_PATA80;
+}
+
+#ifdef __BIG_ENDIAN
+static void tx4939ide_dma_host_set(ide_drive_t *drive, int on)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        u8 unit = drive->dn;
+        void __iomem *base = TX4939IDE_BASE(hwif);
+        u8 dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);
+
+        if (on)
+                dma_stat |= (1 << (5 + unit));
+        else
+                dma_stat &= ~(1 << (5 + unit));
+
+        tx4939ide_writeb(dma_stat, base, TX4939IDE_DMA_Stat);
+}
+#else
+#define tx4939ide_dma_host_set  ide_dma_host_set
+#endif
+
+static u8 tx4939ide_clear_dma_status(void __iomem *base)
+{
+        u8 dma_stat;
+
+        /* read DMA status for INTR & ERROR flags */
+        dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);
+        /* clear INTR & ERROR flags */
+        tx4939ide_writeb(dma_stat | ATA_DMA_INTR | ATA_DMA_ERR, base,
+                         TX4939IDE_DMA_Stat);
+        /* recover intmask cleared by writing to bit2 of DMA_Stat */
+        tx4939ide_writew(TX4939IDE_IGNORE_INTS << 8, base, TX4939IDE_Int_Ctl);
+        return dma_stat;
+}
+
+#ifdef __BIG_ENDIAN
+/* custom ide_build_dmatable to handle swapped layout */
+static int tx4939ide_build_dmatable(ide_drive_t *drive, struct request *rq)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        u32 *table = (u32 *)hwif->dmatable_cpu;
+        unsigned int count = 0;
+        int i;
+        struct scatterlist *sg;
+
+        hwif->sg_nents = ide_build_sglist(drive, rq);
+        if (hwif->sg_nents == 0)
+                return 0;
+
+        for_each_sg(hwif->sg_table, sg, hwif->sg_nents, i) {
+                u32 cur_addr, cur_len, bcount;
+
+                cur_addr = sg_dma_address(sg);
+                cur_len = sg_dma_len(sg);
+
+                /*
+                 * Fill in the DMA table, without crossing any 64kB boundaries.
+                 */
+
+                while (cur_len) {
+                        if (count++ >= PRD_ENTRIES)
+                                goto use_pio_instead;
+
+                        bcount = 0x10000 - (cur_addr & 0xffff);
+                        if (bcount > cur_len)
+                                bcount = cur_len;
+                        *table++ = bcount & 0xffff;
+                        *table++ = cur_addr;
+                        cur_addr += bcount;
+                        cur_len -= bcount;
+                }
+        }
+
+        if (count) {
+                *(table - 2) |= 0x80000000;
+                return count;
+        }
+
+use_pio_instead:
+        printk(KERN_ERR "%s: %s\n", drive->name,
+                count ? "DMA table too small" : "empty DMA table?");
+
+        ide_destroy_dmatable(drive);
+
+        return 0; /* revert to PIO for this request */
+}
+#else
+#define tx4939ide_build_dmatable        ide_build_dmatable
+#endif
+
+static int tx4939ide_dma_setup(ide_drive_t *drive)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        void __iomem *base = TX4939IDE_BASE(hwif);
+        struct request *rq = hwif->hwgroup->rq;
+        u8 reading;
+        int nent;
+
+        if (rq_data_dir(rq))
+                reading = 0;
+        else
+                reading = ATA_DMA_WR;
+
+        /* fall back to PIO! */
+        nent = tx4939ide_build_dmatable(drive, rq);
+        if (!nent) {
+                ide_map_sg(drive, rq);
+                return 1;
+        }
+
+        /* PRD table */
+        tx4939ide_writel(hwif->dmatable_dma, base, TX4939IDE_PRD_Ptr);
+
+        /* specify r/w */
+        tx4939ide_writeb(reading, base, TX4939IDE_DMA_Cmd);
+
+        /* clear INTR & ERROR flags */
+        tx4939ide_clear_dma_status(base);
+
+        drive->waiting_for_dma = 1;
+
+        tx4939ide_writew(SECTOR_SIZE / 2, base, drive->dn ?
+                         TX4939IDE_Xfer_Cnt_2 : TX4939IDE_Xfer_Cnt_1);
+        tx4939ide_writew(rq->nr_sectors, base, TX4939IDE_Sec_Cnt);
+        return 0;
+}
+
+static int tx4939ide_dma_end(ide_drive_t *drive)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        u8 dma_stat, dma_cmd;
+        void __iomem *base = TX4939IDE_BASE(hwif);
+        u16 ctl = tx4939ide_readw(base, TX4939IDE_Int_Ctl);
+
+        drive->waiting_for_dma = 0;
+
+        /* get DMA command mode */
+        dma_cmd = tx4939ide_readb(base, TX4939IDE_DMA_Cmd);
+        /* stop DMA */
+        tx4939ide_writeb(dma_cmd & ~ATA_DMA_START, base, TX4939IDE_DMA_Cmd);
+
+        /* read and clear the INTR & ERROR bits */
+        dma_stat = tx4939ide_clear_dma_status(base);
+
+        /* purge DMA mappings */
+        ide_destroy_dmatable(drive);
+        /* verify good DMA status */
+        wmb();
+
+        if ((dma_stat & (ATA_DMA_INTR | ATA_DMA_ERR | ATA_DMA_ACTIVE)) == 0 &&
+            (ctl & (TX4939IDE_INT_XFEREND | TX4939IDE_INT_HOST)) ==
+            (TX4939IDE_INT_XFEREND | TX4939IDE_INT_HOST))
+                /* INT_IDE lost... bug? */
+                return 0;
+        return ((dma_stat & (ATA_DMA_INTR | ATA_DMA_ERR | ATA_DMA_ACTIVE)) !=
+                ATA_DMA_INTR) ? 0x10 | dma_stat : 0;
+}
+
+/* returns 1 if DMA IRQ issued, 0 otherwise */
+static int tx4939ide_dma_test_irq(ide_drive_t *drive)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        void __iomem *base = TX4939IDE_BASE(hwif);
+        u16 ctl, ide_int;
+        u8 dma_stat, stat;
+        int found = 0;
+
+        ctl = tx4939ide_check_error_ints(hwif);
+        ide_int = ctl & (TX4939IDE_INT_XFEREND | TX4939IDE_INT_HOST);
+        switch (ide_int) {
+        case TX4939IDE_INT_HOST:
+                /* On error, XFEREND might not be asserted. */
+                stat = tx4939ide_readb(base, TX4939IDE_AltStat_DevCtl);
+                if ((stat & (ATA_BUSY | ATA_DRQ | ATA_ERR)) == ATA_ERR)
+                        found = 1;
+                else
+                        /* Wait for XFEREND (Mask HOST and unmask XFEREND) */
+                        ctl &= ~TX4939IDE_INT_XFEREND << 8;
+                ctl |= ide_int << 8;
+                break;
+        case TX4939IDE_INT_HOST | TX4939IDE_INT_XFEREND:
+                dma_stat = tx4939ide_readb(base, TX4939IDE_DMA_Stat);
+                if (!(dma_stat & ATA_DMA_INTR))
+                        pr_warning("%s: weird interrupt status. "
+                                   "DMA_Stat %#02x int_ctl %#04x\n",
+                                   hwif->name, dma_stat, ctl);
+                found = 1;
+                break;
+        }
+        /*
+         * Do not clear XFEREND, HOST now.  They will be cleared by
+         * clearing bit2 of DMA_Stat.
+         */
+        ctl &= ~ide_int;
+        tx4939ide_writew(ctl, base, TX4939IDE_Int_Ctl);
+        return found;
+}
+
+static void tx4939ide_init_hwif(ide_hwif_t *hwif)
+{
+        void __iomem *base = TX4939IDE_BASE(hwif);
+
+        /* Soft Reset */
+        tx4939ide_writew(0x8000, base, TX4939IDE_Sys_Ctl);
+        mmiowb();
+        /* at least 20 GBUSCLK (typ. 100ns @ GBUS200MHz, max 450ns) */
+        ndelay(450);
+        tx4939ide_writew(0x0000, base, TX4939IDE_Sys_Ctl);
+        /* mask some interrupts and clear all interrupts */
+        tx4939ide_writew((TX4939IDE_IGNORE_INTS << 8) | 0xff, base,
+                         TX4939IDE_Int_Ctl);
+
+        tx4939ide_writew(0x0008, base, TX4939IDE_Lo_Burst_Cnt);
+        tx4939ide_writew(0, base, TX4939IDE_Up_Burst_Cnt);
+}
+
+static int tx4939ide_init_dma(ide_hwif_t *hwif, const struct ide_port_info *d)
+{
+        hwif->dma_base =
+                hwif->extra_base + tx4939ide_swizzleb(TX4939IDE_DMA_Cmd);
+        /*
+         * Note that we cannot use ATA_DMA_TABLE_OFS, ATA_DMA_STATUS
+         * for big endian.
+         */
+        return ide_allocate_dma_engine(hwif);
+}
+
+static void tx4939ide_tf_load_fixup(ide_drive_t *drive, ide_task_t *task)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        void __iomem *base = TX4939IDE_BASE(hwif);
+        u16 sysctl = hwif->select_data >> (drive->dn ? 16 : 0);
+
+        /*
+         * Fix ATA100 CORE System Control Register. (The write to the
+         * Device/Head register may write wrong data to the System
+         * Control Register)
+         * While Sys_Ctl is written here, selectproc is not needed.
+         */
+        tx4939ide_writew(sysctl, base, TX4939IDE_Sys_Ctl);
+}
+
+#ifdef __BIG_ENDIAN
+
+static u8 tx4939ide_read_sff_dma_status(ide_hwif_t *hwif)
+{
+        void __iomem *base = TX4939IDE_BASE(hwif);
+
+        return tx4939ide_readb(base, TX4939IDE_DMA_Stat);
+}
+
+/* custom iops (independent from SWAP_IO_SPACE) */
+static u8 tx4939ide_inb(unsigned long port)
+{
+        return __raw_readb((void __iomem *)port);
+}
+
+static void tx4939ide_outb(u8 value, unsigned long port)
+{
+        __raw_writeb(value, (void __iomem *)port);
+}
+
+static void tx4939ide_tf_load(ide_drive_t *drive, ide_task_t *task)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        struct ide_io_ports *io_ports = &hwif->io_ports;
+        struct ide_taskfile *tf = &task->tf;
+        u8 HIHI = task->tf_flags & IDE_TFLAG_LBA48 ? 0xE0 : 0xEF;
+
+        if (task->tf_flags & IDE_TFLAG_FLAGGED)
+                HIHI = 0xFF;
+
+        if (task->tf_flags & IDE_TFLAG_OUT_DATA) {
+                u16 data = (tf->hob_data << 8) | tf->data;
+
+                /* no endian swap */
+                __raw_writew(data, (void __iomem *)io_ports->data_addr);
+        }
+
+        if (task->tf_flags & IDE_TFLAG_OUT_HOB_FEATURE)
+                tx4939ide_outb(tf->hob_feature, io_ports->feature_addr);
+        if (task->tf_flags & IDE_TFLAG_OUT_HOB_NSECT)
+                tx4939ide_outb(tf->hob_nsect, io_ports->nsect_addr);
+        if (task->tf_flags & IDE_TFLAG_OUT_HOB_LBAL)
+                tx4939ide_outb(tf->hob_lbal, io_ports->lbal_addr);
+        if (task->tf_flags & IDE_TFLAG_OUT_HOB_LBAM)
+                tx4939ide_outb(tf->hob_lbam, io_ports->lbam_addr);
+        if (task->tf_flags & IDE_TFLAG_OUT_HOB_LBAH)
+                tx4939ide_outb(tf->hob_lbah, io_ports->lbah_addr);
+
+        if (task->tf_flags & IDE_TFLAG_OUT_FEATURE)
+                tx4939ide_outb(tf->feature, io_ports->feature_addr);
+        if (task->tf_flags & IDE_TFLAG_OUT_NSECT)
+                tx4939ide_outb(tf->nsect, io_ports->nsect_addr);
+        if (task->tf_flags & IDE_TFLAG_OUT_LBAL)
+                tx4939ide_outb(tf->lbal, io_ports->lbal_addr);
+        if (task->tf_flags & IDE_TFLAG_OUT_LBAM)
+                tx4939ide_outb(tf->lbam, io_ports->lbam_addr);
+        if (task->tf_flags & IDE_TFLAG_OUT_LBAH)
+                tx4939ide_outb(tf->lbah, io_ports->lbah_addr);
+
+        if (task->tf_flags & IDE_TFLAG_OUT_DEVICE) {
+                tx4939ide_outb((tf->device & HIHI) | drive->select,
+                               io_ports->device_addr);
+                tx4939ide_tf_load_fixup(drive, task);
+        }
+}
+
+static void tx4939ide_tf_read(ide_drive_t *drive, ide_task_t *task)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        struct ide_io_ports *io_ports = &hwif->io_ports;
+        struct ide_taskfile *tf = &task->tf;
+
+        if (task->tf_flags & IDE_TFLAG_IN_DATA) {
+                u16 data;
+
+                /* no endian swap */
+                data = __raw_readw((void __iomem *)io_ports->data_addr);
+                tf->data = data & 0xff;
+                tf->hob_data = (data >> 8) & 0xff;
+        }
+
+        /* be sure we're looking at the low order bits */
+        tx4939ide_outb(ATA_DEVCTL_OBS & ~0x80, io_ports->ctl_addr);
+
+        if (task->tf_flags & IDE_TFLAG_IN_FEATURE)
+                tf->feature = tx4939ide_inb(io_ports->feature_addr);
+        if (task->tf_flags & IDE_TFLAG_IN_NSECT)
+                tf->nsect  = tx4939ide_inb(io_ports->nsect_addr);
+        if (task->tf_flags & IDE_TFLAG_IN_LBAL)
+                tf->lbal   = tx4939ide_inb(io_ports->lbal_addr);
+        if (task->tf_flags & IDE_TFLAG_IN_LBAM)
+                tf->lbam   = tx4939ide_inb(io_ports->lbam_addr);
+        if (task->tf_flags & IDE_TFLAG_IN_LBAH)
+                tf->lbah   = tx4939ide_inb(io_ports->lbah_addr);
+        if (task->tf_flags & IDE_TFLAG_IN_DEVICE)
+                tf->device = tx4939ide_inb(io_ports->device_addr);
+
+        if (task->tf_flags & IDE_TFLAG_LBA48) {
+                tx4939ide_outb(ATA_DEVCTL_OBS | 0x80, io_ports->ctl_addr);
+
+                if (task->tf_flags & IDE_TFLAG_IN_HOB_FEATURE)
+                        tf->hob_feature =
+                                tx4939ide_inb(io_ports->feature_addr);
+                if (task->tf_flags & IDE_TFLAG_IN_HOB_NSECT)
+                        tf->hob_nsect   = tx4939ide_inb(io_ports->nsect_addr);
+                if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAL)
+                        tf->hob_lbal    = tx4939ide_inb(io_ports->lbal_addr);
+                if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAM)
+                        tf->hob_lbam    = tx4939ide_inb(io_ports->lbam_addr);
+                if (task->tf_flags & IDE_TFLAG_IN_HOB_LBAH)
+                        tf->hob_lbah    = tx4939ide_inb(io_ports->lbah_addr);
+        }
+}
+
+static void tx4939ide_input_data_swap(ide_drive_t *drive, struct request *rq,
+                                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, count * 2);
+}
+
+static void tx4939ide_output_data_swap(ide_drive_t *drive, struct request *rq,
+                                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, count * 2);
+}
+
+static const struct ide_tp_ops tx4939ide_tp_ops = {
+        .exec_command           = ide_exec_command,
+        .read_status            = ide_read_status,
+        .read_altstatus         = ide_read_altstatus,
+        .read_sff_dma_status    = tx4939ide_read_sff_dma_status,
+
+        .set_irq                = ide_set_irq,
+
+        .tf_load                = tx4939ide_tf_load,
+        .tf_read                = tx4939ide_tf_read,
+
+        .input_data             = tx4939ide_input_data_swap,
+        .output_data            = tx4939ide_output_data_swap,
+};
+
+#else   /* __LITTLE_ENDIAN */
+
+static void tx4939ide_tf_load(ide_drive_t *drive, ide_task_t *task)
+{
+        ide_tf_load(drive, task);
+        if (task->tf_flags & IDE_TFLAG_OUT_DEVICE)
+                tx4939ide_tf_load_fixup(drive, task);
+}
+
+static const struct ide_tp_ops tx4939ide_tp_ops = {
+        .exec_command           = ide_exec_command,
+        .read_status            = ide_read_status,
+        .read_altstatus         = ide_read_altstatus,
+        .read_sff_dma_status    = ide_read_sff_dma_status,
+
+        .set_irq                = ide_set_irq,
+
+        .tf_load                = tx4939ide_tf_load,
+        .tf_read                = ide_tf_read,
+
+        .input_data             = ide_input_data,
+        .output_data            = ide_output_data,
+};
+
+#endif  /* __LITTLE_ENDIAN */
+
+static const struct ide_port_ops tx4939ide_port_ops = {
+        .set_pio_mode = tx4939ide_set_pio_mode,
+        .set_dma_mode = tx4939ide_set_dma_mode,
+        .clear_irq = tx4939ide_clear_irq,
+        .cable_detect = tx4939ide_cable_detect,
+};
+
+static const struct ide_dma_ops tx4939ide_dma_ops = {
+        .dma_host_set = tx4939ide_dma_host_set,
+        .dma_setup = tx4939ide_dma_setup,
+        .dma_exec_cmd = ide_dma_exec_cmd,
+        .dma_start = ide_dma_start,
+        .dma_end = tx4939ide_dma_end,
+        .dma_test_irq = tx4939ide_dma_test_irq,
+        .dma_lost_irq = ide_dma_lost_irq,
+        .dma_timeout = ide_dma_timeout,
+};
+
+static const struct ide_port_info tx4939ide_port_info __initdata = {
+        .init_hwif = tx4939ide_init_hwif,
+        .init_dma = tx4939ide_init_dma,
+        .port_ops = &tx4939ide_port_ops,
+        .dma_ops = &tx4939ide_dma_ops,
+        .tp_ops = &tx4939ide_tp_ops,
+        .host_flags = IDE_HFLAG_MMIO,
+        .pio_mask = ATA_PIO4,
+        .mwdma_mask = ATA_MWDMA2,
+        .udma_mask = ATA_UDMA5,
+};
+
+static int __init tx4939ide_probe(struct platform_device *pdev)
+{
+        hw_regs_t hw;
+        hw_regs_t *hws[] = { &hw, NULL, NULL, NULL };
+        struct ide_host *host;
+        struct resource *res;
+        int irq, ret;
+        unsigned long mapbase;
+
+        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,
+                                     res->end - res->start + 1, "tx4938ide"))
+                return -EBUSY;
+        mapbase = (unsigned long)devm_ioremap(&pdev->dev, res->start,
+                                              res->end - res->start + 1);
+        if (!mapbase)
+                return -EBUSY;
+        memset(&hw, 0, sizeof(hw));
+        hw.io_ports.data_addr =
+                mapbase + tx4939ide_swizzlew(TX4939IDE_Data);
+        hw.io_ports.error_addr =
+                mapbase + tx4939ide_swizzleb(TX4939IDE_Error_Feature);
+        hw.io_ports.nsect_addr =
+                mapbase + tx4939ide_swizzleb(TX4939IDE_Sec);
+        hw.io_ports.lbal_addr =
+                mapbase + tx4939ide_swizzleb(TX4939IDE_LBA0);
+        hw.io_ports.lbam_addr =
+                mapbase + tx4939ide_swizzleb(TX4939IDE_LBA1);
+        hw.io_ports.lbah_addr =
+                mapbase + tx4939ide_swizzleb(TX4939IDE_LBA2);
+        hw.io_ports.device_addr =
+                mapbase + tx4939ide_swizzleb(TX4939IDE_DevHead);
+        hw.io_ports.command_addr =
+                mapbase + tx4939ide_swizzleb(TX4939IDE_Stat_Cmd);
+        hw.io_ports.ctl_addr =
+                mapbase + tx4939ide_swizzleb(TX4939IDE_AltStat_DevCtl);
+        hw.irq = irq;
+        hw.dev = &pdev->dev;
+
+        pr_info("TX4939 IDE interface (base %#lx, irq %d)\n", mapbase, irq);
+        host = ide_host_alloc(&tx4939ide_port_info, hws);
+        if (!host)
+                return -ENOMEM;
+        /* use extra_base for base address of the all registers */
+        host->ports[0]->extra_base = mapbase;
+        ret = ide_host_register(host, &tx4939ide_port_info, hws);
+        if (ret) {
+                ide_host_free(host);
+                return ret;
+        }
+        platform_set_drvdata(pdev, host);
+        return 0;
+}
+
+static int __exit tx4939ide_remove(struct platform_device *pdev)
+{
+        struct ide_host *host = platform_get_drvdata(pdev);
+
+        ide_host_remove(host);
+        return 0;
+}
+
+#ifdef CONFIG_PM
+static int tx4939ide_resume(struct platform_device *dev)
+{
+        struct ide_host *host = platform_get_drvdata(dev);
+        ide_hwif_t *hwif = host->ports[0];
+
+        tx4939ide_init_hwif(hwif);
+        return 0;
+}
+#else
+#define tx4939ide_resume        NULL
+#endif
+
+static struct platform_driver tx4939ide_driver = {
+        .driver = {
+                .name = MODNAME,
+                .owner = THIS_MODULE,
+        },
+        .remove = __exit_p(tx4939ide_remove),
+        .resume = tx4939ide_resume,
+};
+
+static int __init tx4939ide_init(void)
+{
+        return platform_driver_probe(&tx4939ide_driver, tx4939ide_probe);
+}
+
+static void __exit tx4939ide_exit(void)
+{
+        platform_driver_unregister(&tx4939ide_driver);
+}
+
+module_init(tx4939ide_init);
+module_exit(tx4939ide_exit);
+
+MODULE_DESCRIPTION("TX4939 internal IDE driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:tx4939ide");