ide-pmac: remove pmac_ide_{m,u}dma_enable() (take 2)

[deliverable/linux.git] / drivers / ide / ppc / pmac.c

/*
 * linux/drivers/ide/ppc/pmac.c
 *
 * Support for IDE interfaces on PowerMacs.
 * These IDE interfaces are memory-mapped and have a DBDMA channel
 * for doing DMA.
 *
 *  Copyright (C) 1998-2003 Paul Mackerras & Ben. Herrenschmidt
 *  Copyright (C)      2007 Bartlomiej Zolnierkiewicz
 *
 *  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 of the License, or (at your option) any later version.
 *
 * Some code taken from drivers/ide/ide-dma.c:
 *
 *  Copyright (c) 1995-1998  Mark Lord
 *
 * TODO: - Use pre-calculated (kauai) timing tables all the time and
 * get rid of the "rounded" tables used previously, so we have the
 * same table format for all controllers and can then just have one
 * big table
 * 
 */
#include <linux/types.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/ide.h>
#include <linux/notifier.h>
#include <linux/reboot.h>
#include <linux/pci.h>
#include <linux/adb.h>
#include <linux/pmu.h>
#include <linux/scatterlist.h>

#include <asm/prom.h>
#include <asm/io.h>
#include <asm/dbdma.h>
#include <asm/ide.h>
#include <asm/pci-bridge.h>
#include <asm/machdep.h>
#include <asm/pmac_feature.h>
#include <asm/sections.h>
#include <asm/irq.h>

#ifndef CONFIG_PPC64
#include <asm/mediabay.h>
#endif

#include "../ide-timing.h"

#undef IDE_PMAC_DEBUG

#define DMA_WAIT_TIMEOUT        50

typedef struct pmac_ide_hwif {
        unsigned long                   regbase;
        int                             irq;
        int                             kind;
        int                             aapl_bus_id;
        unsigned                        cable_80 : 1;
        unsigned                        mediabay : 1;
        unsigned                        broken_dma : 1;
        unsigned                        broken_dma_warn : 1;
        struct device_node*             node;
        struct macio_dev                *mdev;
        u32                             timings[4];
        volatile u32 __iomem *          *kauai_fcr;
#ifdef CONFIG_BLK_DEV_IDEDMA_PMAC
        /* Those fields are duplicating what is in hwif. We currently
         * can't use the hwif ones because of some assumptions that are
         * beeing done by the generic code about the kind of dma controller
         * and format of the dma table. This will have to be fixed though.
         */
        volatile struct dbdma_regs __iomem *    dma_regs;
        struct dbdma_cmd*               dma_table_cpu;
#endif
        
} pmac_ide_hwif_t;

static pmac_ide_hwif_t pmac_ide[MAX_HWIFS];
static int pmac_ide_count;

enum {
        controller_ohare,       /* OHare based */
        controller_heathrow,    /* Heathrow/Paddington */
        controller_kl_ata3,     /* KeyLargo ATA-3 */
        controller_kl_ata4,     /* KeyLargo ATA-4 */
        controller_un_ata6,     /* UniNorth2 ATA-6 */
        controller_k2_ata6,     /* K2 ATA-6 */
        controller_sh_ata6,     /* Shasta ATA-6 */
};

static const char* model_name[] = {
        "OHare ATA",            /* OHare based */
        "Heathrow ATA",         /* Heathrow/Paddington */
        "KeyLargo ATA-3",       /* KeyLargo ATA-3 (MDMA only) */
        "KeyLargo ATA-4",       /* KeyLargo ATA-4 (UDMA/66) */
        "UniNorth ATA-6",       /* UniNorth2 ATA-6 (UDMA/100) */
        "K2 ATA-6",             /* K2 ATA-6 (UDMA/100) */
        "Shasta ATA-6",         /* Shasta ATA-6 (UDMA/133) */
};

/*
 * Extra registers, both 32-bit little-endian
 */
#define IDE_TIMING_CONFIG       0x200
#define IDE_INTERRUPT           0x300

/* Kauai (U2) ATA has different register setup */
#define IDE_KAUAI_PIO_CONFIG    0x200
#define IDE_KAUAI_ULTRA_CONFIG  0x210
#define IDE_KAUAI_POLL_CONFIG   0x220

/*
 * Timing configuration register definitions
 */

/* Number of IDE_SYSCLK_NS ticks, argument is in nanoseconds */
#define SYSCLK_TICKS(t)         (((t) + IDE_SYSCLK_NS - 1) / IDE_SYSCLK_NS)
#define SYSCLK_TICKS_66(t)      (((t) + IDE_SYSCLK_66_NS - 1) / IDE_SYSCLK_66_NS)
#define IDE_SYSCLK_NS           30      /* 33Mhz cell */
#define IDE_SYSCLK_66_NS        15      /* 66Mhz cell */

/* 133Mhz cell, found in shasta.
 * See comments about 100 Mhz Uninorth 2...
 * Note that PIO_MASK and MDMA_MASK seem to overlap
 */
#define TR_133_PIOREG_PIO_MASK          0xff000fff
#define TR_133_PIOREG_MDMA_MASK         0x00fff800
#define TR_133_UDMAREG_UDMA_MASK        0x0003ffff
#define TR_133_UDMAREG_UDMA_EN          0x00000001

/* 100Mhz cell, found in Uninorth 2. I don't have much infos about
 * this one yet, it appears as a pci device (106b/0033) on uninorth
 * internal PCI bus and it's clock is controlled like gem or fw. It
 * appears to be an evolution of keylargo ATA4 with a timing register
 * extended to 2 32bits registers and a similar DBDMA channel. Other
 * registers seem to exist but I can't tell much about them.
 * 
 * So far, I'm using pre-calculated tables for this extracted from
 * the values used by the MacOS X driver.
 * 
 * The "PIO" register controls PIO and MDMA timings, the "ULTRA"
 * register controls the UDMA timings. At least, it seems bit 0
 * of this one enables UDMA vs. MDMA, and bits 4..7 are the
 * cycle time in units of 10ns. Bits 8..15 are used by I don't
 * know their meaning yet
 */
#define TR_100_PIOREG_PIO_MASK          0xff000fff
#define TR_100_PIOREG_MDMA_MASK         0x00fff000
#define TR_100_UDMAREG_UDMA_MASK        0x0000ffff
#define TR_100_UDMAREG_UDMA_EN          0x00000001


/* 66Mhz cell, found in KeyLargo. Can do ultra mode 0 to 2 on
 * 40 connector cable and to 4 on 80 connector one.
 * Clock unit is 15ns (66Mhz)
 * 
 * 3 Values can be programmed:
 *  - Write data setup, which appears to match the cycle time. They
 *    also call it DIOW setup.
 *  - Ready to pause time (from spec)
 *  - Address setup. That one is weird. I don't see where exactly
 *    it fits in UDMA cycles, I got it's name from an obscure piece
 *    of commented out code in Darwin. They leave it to 0, we do as
 *    well, despite a comment that would lead to think it has a
 *    min value of 45ns.
 * Apple also add 60ns to the write data setup (or cycle time ?) on
 * reads.
 */
#define TR_66_UDMA_MASK                 0xfff00000
#define TR_66_UDMA_EN                   0x00100000 /* Enable Ultra mode for DMA */
#define TR_66_UDMA_ADDRSETUP_MASK       0xe0000000 /* Address setup */
#define TR_66_UDMA_ADDRSETUP_SHIFT      29
#define TR_66_UDMA_RDY2PAUS_MASK        0x1e000000 /* Ready 2 pause time */
#define TR_66_UDMA_RDY2PAUS_SHIFT       25
#define TR_66_UDMA_WRDATASETUP_MASK     0x01e00000 /* Write data setup time */
#define TR_66_UDMA_WRDATASETUP_SHIFT    21
#define TR_66_MDMA_MASK                 0x000ffc00
#define TR_66_MDMA_RECOVERY_MASK        0x000f8000
#define TR_66_MDMA_RECOVERY_SHIFT       15
#define TR_66_MDMA_ACCESS_MASK          0x00007c00
#define TR_66_MDMA_ACCESS_SHIFT         10
#define TR_66_PIO_MASK                  0x000003ff
#define TR_66_PIO_RECOVERY_MASK         0x000003e0
#define TR_66_PIO_RECOVERY_SHIFT        5
#define TR_66_PIO_ACCESS_MASK           0x0000001f
#define TR_66_PIO_ACCESS_SHIFT          0

/* 33Mhz cell, found in OHare, Heathrow (& Paddington) and KeyLargo
 * Can do pio & mdma modes, clock unit is 30ns (33Mhz)
 * 
 * The access time and recovery time can be programmed. Some older
 * Darwin code base limit OHare to 150ns cycle time. I decided to do
 * the same here fore safety against broken old hardware ;)
 * The HalfTick bit, when set, adds half a clock (15ns) to the access
 * time and removes one from recovery. It's not supported on KeyLargo
 * implementation afaik. The E bit appears to be set for PIO mode 0 and
 * is used to reach long timings used in this mode.
 */
#define TR_33_MDMA_MASK                 0x003ff800
#define TR_33_MDMA_RECOVERY_MASK        0x001f0000
#define TR_33_MDMA_RECOVERY_SHIFT       16
#define TR_33_MDMA_ACCESS_MASK          0x0000f800
#define TR_33_MDMA_ACCESS_SHIFT         11
#define TR_33_MDMA_HALFTICK             0x00200000
#define TR_33_PIO_MASK                  0x000007ff
#define TR_33_PIO_E                     0x00000400
#define TR_33_PIO_RECOVERY_MASK         0x000003e0
#define TR_33_PIO_RECOVERY_SHIFT        5
#define TR_33_PIO_ACCESS_MASK           0x0000001f
#define TR_33_PIO_ACCESS_SHIFT          0

/*
 * Interrupt register definitions
 */
#define IDE_INTR_DMA                    0x80000000
#define IDE_INTR_DEVICE                 0x40000000

/*
 * FCR Register on Kauai. Not sure what bit 0x4 is  ...
 */
#define KAUAI_FCR_UATA_MAGIC            0x00000004
#define KAUAI_FCR_UATA_RESET_N          0x00000002
#define KAUAI_FCR_UATA_ENABLE           0x00000001

#ifdef CONFIG_BLK_DEV_IDEDMA_PMAC

/* Rounded Multiword DMA timings
 * 
 * I gave up finding a generic formula for all controller
 * types and instead, built tables based on timing values
 * used by Apple in Darwin's implementation.
 */
struct mdma_timings_t {
        int     accessTime;
        int     recoveryTime;
        int     cycleTime;
};

struct mdma_timings_t mdma_timings_33[] =
{
    { 240, 240, 480 },
    { 180, 180, 360 },
    { 135, 135, 270 },
    { 120, 120, 240 },
    { 105, 105, 210 },
    {  90,  90, 180 },
    {  75,  75, 150 },
    {  75,  45, 120 },
    {   0,   0,   0 }
};

struct mdma_timings_t mdma_timings_33k[] =
{
    { 240, 240, 480 },
    { 180, 180, 360 },
    { 150, 150, 300 },
    { 120, 120, 240 },
    {  90, 120, 210 },
    {  90,  90, 180 },
    {  90,  60, 150 },
    {  90,  30, 120 },
    {   0,   0,   0 }
};

struct mdma_timings_t mdma_timings_66[] =
{
    { 240, 240, 480 },
    { 180, 180, 360 },
    { 135, 135, 270 },
    { 120, 120, 240 },
    { 105, 105, 210 },
    {  90,  90, 180 },
    {  90,  75, 165 },
    {  75,  45, 120 },
    {   0,   0,   0 }
};

/* KeyLargo ATA-4 Ultra DMA timings (rounded) */
struct {
        int     addrSetup; /* ??? */
        int     rdy2pause;
        int     wrDataSetup;
} kl66_udma_timings[] =
{
    {   0, 180,  120 }, /* Mode 0 */
    {   0, 150,  90 },  /*      1 */
    {   0, 120,  60 },  /*      2 */
    {   0, 90,   45 },  /*      3 */
    {   0, 90,   30 }   /*      4 */
};

/* UniNorth 2 ATA/100 timings */
struct kauai_timing {
        int     cycle_time;
        u32     timing_reg;
};

static struct kauai_timing      kauai_pio_timings[] =
{
        { 930   , 0x08000fff },
        { 600   , 0x08000a92 },
        { 383   , 0x0800060f },
        { 360   , 0x08000492 },
        { 330   , 0x0800048f },
        { 300   , 0x080003cf },
        { 270   , 0x080003cc },
        { 240   , 0x0800038b },
        { 239   , 0x0800030c },
        { 180   , 0x05000249 },
        { 120   , 0x04000148 },
        { 0     , 0 },
};

static struct kauai_timing      kauai_mdma_timings[] =
{
        { 1260  , 0x00fff000 },
        { 480   , 0x00618000 },
        { 360   , 0x00492000 },
        { 270   , 0x0038e000 },
        { 240   , 0x0030c000 },
        { 210   , 0x002cb000 },
        { 180   , 0x00249000 },
        { 150   , 0x00209000 },
        { 120   , 0x00148000 },
        { 0     , 0 },
};

static struct kauai_timing      kauai_udma_timings[] =
{
        { 120   , 0x000070c0 },
        { 90    , 0x00005d80 },
        { 60    , 0x00004a60 },
        { 45    , 0x00003a50 },
        { 30    , 0x00002a30 },
        { 20    , 0x00002921 },
        { 0     , 0 },
};

static struct kauai_timing      shasta_pio_timings[] =
{
        { 930   , 0x08000fff },
        { 600   , 0x0A000c97 },
        { 383   , 0x07000712 },
        { 360   , 0x040003cd },
        { 330   , 0x040003cd },
        { 300   , 0x040003cd },
        { 270   , 0x040003cd },
        { 240   , 0x040003cd },
        { 239   , 0x040003cd },
        { 180   , 0x0400028b },
        { 120   , 0x0400010a },
        { 0     , 0 },
};

static struct kauai_timing      shasta_mdma_timings[] =
{
        { 1260  , 0x00fff000 },
        { 480   , 0x00820800 },
        { 360   , 0x00820800 },
        { 270   , 0x00820800 },
        { 240   , 0x00820800 },
        { 210   , 0x00820800 },
        { 180   , 0x00820800 },
        { 150   , 0x0028b000 },
        { 120   , 0x001ca000 },
        { 0     , 0 },
};

static struct kauai_timing      shasta_udma133_timings[] =
{
        { 120   , 0x00035901, },
        { 90    , 0x000348b1, },
        { 60    , 0x00033881, },
        { 45    , 0x00033861, },
        { 30    , 0x00033841, },
        { 20    , 0x00033031, },
        { 15    , 0x00033021, },
        { 0     , 0 },
};


static inline u32
kauai_lookup_timing(struct kauai_timing* table, int cycle_time)
{
        int i;
        
        for (i=0; table[i].cycle_time; i++)
                if (cycle_time > table[i+1].cycle_time)
                        return table[i].timing_reg;
        BUG();
        return 0;
}

/* allow up to 256 DBDMA commands per xfer */
#define MAX_DCMDS               256

/* 
 * Wait 1s for disk to answer on IDE bus after a hard reset
 * of the device (via GPIO/FCR).
 * 
 * Some devices seem to "pollute" the bus even after dropping
 * the BSY bit (typically some combo drives slave on the UDMA
 * bus) after a hard reset. Since we hard reset all drives on
 * KeyLargo ATA66, we have to keep that delay around. I may end
 * up not hard resetting anymore on these and keep the delay only
 * for older interfaces instead (we have to reset when coming
 * from MacOS...) --BenH. 
 */
#define IDE_WAKEUP_DELAY        (1*HZ)

static void pmac_ide_setup_dma(pmac_ide_hwif_t *pmif, ide_hwif_t *hwif);
static int pmac_ide_build_dmatable(ide_drive_t *drive, struct request *rq);
static void pmac_ide_selectproc(ide_drive_t *drive);
static void pmac_ide_kauai_selectproc(ide_drive_t *drive);

#endif /* CONFIG_BLK_DEV_IDEDMA_PMAC */

/*
 * N.B. this can't be an initfunc, because the media-bay task can
 * call ide_[un]register at any time.
 */
void
pmac_ide_init_hwif_ports(hw_regs_t *hw,
                              unsigned long data_port, unsigned long ctrl_port,
                              int *irq)
{
        int i, ix;

        if (data_port == 0)
                return;

        for (ix = 0; ix < MAX_HWIFS; ++ix)
                if (data_port == pmac_ide[ix].regbase)
                        break;

        if (ix >= MAX_HWIFS) {
                /* Probably a PCI interface... */
                for (i = IDE_DATA_OFFSET; i <= IDE_STATUS_OFFSET; ++i)
                        hw->io_ports[i] = data_port + i - IDE_DATA_OFFSET;
                hw->io_ports[IDE_CONTROL_OFFSET] = ctrl_port;
                return;
        }

        for (i = 0; i < 8; ++i)
                hw->io_ports[i] = data_port + i * 0x10;
        hw->io_ports[8] = data_port + 0x160;

        if (irq != NULL)
                *irq = pmac_ide[ix].irq;

        hw->dev = &pmac_ide[ix].mdev->ofdev.dev;
}

#define PMAC_IDE_REG(x) ((void __iomem *)(IDE_DATA_REG+(x)))

/*
 * Apply the timings of the proper unit (master/slave) to the shared
 * timing register when selecting that unit. This version is for
 * ASICs with a single timing register
 */
static void
pmac_ide_selectproc(ide_drive_t *drive)
{
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)HWIF(drive)->hwif_data;

        if (pmif == NULL)
                return;

        if (drive->select.b.unit & 0x01)
                writel(pmif->timings[1], PMAC_IDE_REG(IDE_TIMING_CONFIG));
        else
                writel(pmif->timings[0], PMAC_IDE_REG(IDE_TIMING_CONFIG));
        (void)readl(PMAC_IDE_REG(IDE_TIMING_CONFIG));
}

/*
 * Apply the timings of the proper unit (master/slave) to the shared
 * timing register when selecting that unit. This version is for
 * ASICs with a dual timing register (Kauai)
 */
static void
pmac_ide_kauai_selectproc(ide_drive_t *drive)
{
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)HWIF(drive)->hwif_data;

        if (pmif == NULL)
                return;

        if (drive->select.b.unit & 0x01) {
                writel(pmif->timings[1], PMAC_IDE_REG(IDE_KAUAI_PIO_CONFIG));
                writel(pmif->timings[3], PMAC_IDE_REG(IDE_KAUAI_ULTRA_CONFIG));
        } else {
                writel(pmif->timings[0], PMAC_IDE_REG(IDE_KAUAI_PIO_CONFIG));
                writel(pmif->timings[2], PMAC_IDE_REG(IDE_KAUAI_ULTRA_CONFIG));
        }
        (void)readl(PMAC_IDE_REG(IDE_KAUAI_PIO_CONFIG));
}

/*
 * Force an update of controller timing values for a given drive
 */
static void
pmac_ide_do_update_timings(ide_drive_t *drive)
{
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)HWIF(drive)->hwif_data;

        if (pmif == NULL)
                return;

        if (pmif->kind == controller_sh_ata6 ||
            pmif->kind == controller_un_ata6 ||
            pmif->kind == controller_k2_ata6)
                pmac_ide_kauai_selectproc(drive);
        else
                pmac_ide_selectproc(drive);
}

static void
pmac_outbsync(ide_drive_t *drive, u8 value, unsigned long port)
{
        u32 tmp;
        
        writeb(value, (void __iomem *) port);
        tmp = readl(PMAC_IDE_REG(IDE_TIMING_CONFIG));
}

/*
 * Send the SET_FEATURE IDE command to the drive and update drive->id with
 * the new state. We currently don't use the generic routine as it used to
 * cause various trouble, especially with older mediabays.
 * This code is sometimes triggering a spurrious interrupt though, I need
 * to sort that out sooner or later and see if I can finally get the
 * common version to work properly in all cases
 */
static int
pmac_ide_do_setfeature(ide_drive_t *drive, u8 command)
{
        ide_hwif_t *hwif = HWIF(drive);
        int result = 1;
        
        disable_irq_nosync(hwif->irq);
        udelay(1);
        SELECT_DRIVE(drive);
        SELECT_MASK(drive, 0);
        udelay(1);
        /* Get rid of pending error state */
        (void) hwif->INB(IDE_STATUS_REG);
        /* Timeout bumped for some powerbooks */
        if (wait_for_ready(drive, 2000)) {
                /* Timeout bumped for some powerbooks */
                printk(KERN_ERR "%s: pmac_ide_do_setfeature disk not ready "
                        "before SET_FEATURE!\n", drive->name);
                goto out;
        }
        udelay(10);
        hwif->OUTB(drive->ctl | 2, IDE_CONTROL_REG);
        hwif->OUTB(command, IDE_NSECTOR_REG);
        hwif->OUTB(SETFEATURES_XFER, IDE_FEATURE_REG);
        hwif->OUTBSYNC(drive, WIN_SETFEATURES, IDE_COMMAND_REG);
        udelay(1);
        /* Timeout bumped for some powerbooks */
        result = wait_for_ready(drive, 2000);
        hwif->OUTB(drive->ctl, IDE_CONTROL_REG);
        if (result)
                printk(KERN_ERR "%s: pmac_ide_do_setfeature disk not ready "
                        "after SET_FEATURE !\n", drive->name);
out:
        SELECT_MASK(drive, 0);
        if (result == 0) {
                drive->id->dma_ultra &= ~0xFF00;
                drive->id->dma_mword &= ~0x0F00;
                drive->id->dma_1word &= ~0x0F00;
                switch(command) {
                        case XFER_UDMA_7:
                                drive->id->dma_ultra |= 0x8080; break;
                        case XFER_UDMA_6:
                                drive->id->dma_ultra |= 0x4040; break;
                        case XFER_UDMA_5:
                                drive->id->dma_ultra |= 0x2020; break;
                        case XFER_UDMA_4:
                                drive->id->dma_ultra |= 0x1010; break;
                        case XFER_UDMA_3:
                                drive->id->dma_ultra |= 0x0808; break;
                        case XFER_UDMA_2:
                                drive->id->dma_ultra |= 0x0404; break;
                        case XFER_UDMA_1:
                                drive->id->dma_ultra |= 0x0202; break;
                        case XFER_UDMA_0:
                                drive->id->dma_ultra |= 0x0101; break;
                        case XFER_MW_DMA_2:
                                drive->id->dma_mword |= 0x0404; break;
                        case XFER_MW_DMA_1:
                                drive->id->dma_mword |= 0x0202; break;
                        case XFER_MW_DMA_0:
                                drive->id->dma_mword |= 0x0101; break;
                        case XFER_SW_DMA_2:
                                drive->id->dma_1word |= 0x0404; break;
                        case XFER_SW_DMA_1:
                                drive->id->dma_1word |= 0x0202; break;
                        case XFER_SW_DMA_0:
                                drive->id->dma_1word |= 0x0101; break;
                        default: break;
                }
                if (!drive->init_speed)
                        drive->init_speed = command;
                drive->current_speed = command;
        }
        enable_irq(hwif->irq);
        return result;
}

/*
 * Old tuning functions (called on hdparm -p), sets up drive PIO timings
 */
static void
pmac_ide_set_pio_mode(ide_drive_t *drive, const u8 pio)
{
        u32 *timings;
        unsigned accessTicks, recTicks;
        unsigned accessTime, recTime;
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)HWIF(drive)->hwif_data;
        unsigned int cycle_time;

        if (pmif == NULL)
                return;
                
        /* which drive is it ? */
        timings = &pmif->timings[drive->select.b.unit & 0x01];

        cycle_time = ide_pio_cycle_time(drive, pio);

        switch (pmif->kind) {
        case controller_sh_ata6: {
                /* 133Mhz cell */
                u32 tr = kauai_lookup_timing(shasta_pio_timings, cycle_time);
                *timings = ((*timings) & ~TR_133_PIOREG_PIO_MASK) | tr;
                break;
                }
        case controller_un_ata6:
        case controller_k2_ata6: {
                /* 100Mhz cell */
                u32 tr = kauai_lookup_timing(kauai_pio_timings, cycle_time);
                *timings = ((*timings) & ~TR_100_PIOREG_PIO_MASK) | tr;
                break;
                }
        case controller_kl_ata4:
                /* 66Mhz cell */
                recTime = cycle_time - ide_pio_timings[pio].active_time
                                - ide_pio_timings[pio].setup_time;
                recTime = max(recTime, 150U);
                accessTime = ide_pio_timings[pio].active_time;
                accessTime = max(accessTime, 150U);
                accessTicks = SYSCLK_TICKS_66(accessTime);
                accessTicks = min(accessTicks, 0x1fU);
                recTicks = SYSCLK_TICKS_66(recTime);
                recTicks = min(recTicks, 0x1fU);
                *timings = ((*timings) & ~TR_66_PIO_MASK) |
                                (accessTicks << TR_66_PIO_ACCESS_SHIFT) |
                                (recTicks << TR_66_PIO_RECOVERY_SHIFT);
                break;
        default: {
                /* 33Mhz cell */
                int ebit = 0;
                recTime = cycle_time - ide_pio_timings[pio].active_time
                                - ide_pio_timings[pio].setup_time;
                recTime = max(recTime, 150U);
                accessTime = ide_pio_timings[pio].active_time;
                accessTime = max(accessTime, 150U);
                accessTicks = SYSCLK_TICKS(accessTime);
                accessTicks = min(accessTicks, 0x1fU);
                accessTicks = max(accessTicks, 4U);
                recTicks = SYSCLK_TICKS(recTime);
                recTicks = min(recTicks, 0x1fU);
                recTicks = max(recTicks, 5U) - 4;
                if (recTicks > 9) {
                        recTicks--; /* guess, but it's only for PIO0, so... */
                        ebit = 1;
                }
                *timings = ((*timings) & ~TR_33_PIO_MASK) |
                                (accessTicks << TR_33_PIO_ACCESS_SHIFT) |
                                (recTicks << TR_33_PIO_RECOVERY_SHIFT);
                if (ebit)
                        *timings |= TR_33_PIO_E;
                break;
                }
        }

#ifdef IDE_PMAC_DEBUG
        printk(KERN_ERR "%s: Set PIO timing for mode %d, reg: 0x%08x\n",
                drive->name, pio,  *timings);
#endif  

        if (pmac_ide_do_setfeature(drive, XFER_PIO_0 + pio))
                return;

        pmac_ide_do_update_timings(drive);
}

#ifdef CONFIG_BLK_DEV_IDEDMA_PMAC

/*
 * Calculate KeyLargo ATA/66 UDMA timings
 */
static int
set_timings_udma_ata4(u32 *timings, u8 speed)
{
        unsigned rdyToPauseTicks, wrDataSetupTicks, addrTicks;

        if (speed > XFER_UDMA_4)
                return 1;

        rdyToPauseTicks = SYSCLK_TICKS_66(kl66_udma_timings[speed & 0xf].rdy2pause);
        wrDataSetupTicks = SYSCLK_TICKS_66(kl66_udma_timings[speed & 0xf].wrDataSetup);
        addrTicks = SYSCLK_TICKS_66(kl66_udma_timings[speed & 0xf].addrSetup);

        *timings = ((*timings) & ~(TR_66_UDMA_MASK | TR_66_MDMA_MASK)) |
                        (wrDataSetupTicks << TR_66_UDMA_WRDATASETUP_SHIFT) | 
                        (rdyToPauseTicks << TR_66_UDMA_RDY2PAUS_SHIFT) |
                        (addrTicks <<TR_66_UDMA_ADDRSETUP_SHIFT) |
                        TR_66_UDMA_EN;
#ifdef IDE_PMAC_DEBUG
        printk(KERN_ERR "ide_pmac: Set UDMA timing for mode %d, reg: 0x%08x\n",
                speed & 0xf,  *timings);
#endif  

        return 0;
}

/*
 * Calculate Kauai ATA/100 UDMA timings
 */
static int
set_timings_udma_ata6(u32 *pio_timings, u32 *ultra_timings, u8 speed)
{
        struct ide_timing *t = ide_timing_find_mode(speed);
        u32 tr;

        if (speed > XFER_UDMA_5 || t == NULL)
                return 1;
        tr = kauai_lookup_timing(kauai_udma_timings, (int)t->udma);
        *ultra_timings = ((*ultra_timings) & ~TR_100_UDMAREG_UDMA_MASK) | tr;
        *ultra_timings = (*ultra_timings) | TR_100_UDMAREG_UDMA_EN;

        return 0;
}

/*
 * Calculate Shasta ATA/133 UDMA timings
 */
static int
set_timings_udma_shasta(u32 *pio_timings, u32 *ultra_timings, u8 speed)
{
        struct ide_timing *t = ide_timing_find_mode(speed);
        u32 tr;

        if (speed > XFER_UDMA_6 || t == NULL)
                return 1;
        tr = kauai_lookup_timing(shasta_udma133_timings, (int)t->udma);
        *ultra_timings = ((*ultra_timings) & ~TR_133_UDMAREG_UDMA_MASK) | tr;
        *ultra_timings = (*ultra_timings) | TR_133_UDMAREG_UDMA_EN;

        return 0;
}

/*
 * Calculate MDMA timings for all cells
 */
static void
set_timings_mdma(ide_drive_t *drive, int intf_type, u32 *timings, u32 *timings2,
                        u8 speed)
{
        int cycleTime, accessTime = 0, recTime = 0;
        unsigned accessTicks, recTicks;
        struct hd_driveid *id = drive->id;
        struct mdma_timings_t* tm = NULL;
        int i;

        /* Get default cycle time for mode */
        switch(speed & 0xf) {
                case 0: cycleTime = 480; break;
                case 1: cycleTime = 150; break;
                case 2: cycleTime = 120; break;
                default:
                        BUG();
                        break;
        }

        /* Check if drive provides explicit DMA cycle time */
        if ((id->field_valid & 2) && id->eide_dma_time)
                cycleTime = max_t(int, id->eide_dma_time, cycleTime);

        /* OHare limits according to some old Apple sources */  
        if ((intf_type == controller_ohare) && (cycleTime < 150))
                cycleTime = 150;
        /* Get the proper timing array for this controller */
        switch(intf_type) {
                case controller_sh_ata6:
                case controller_un_ata6:
                case controller_k2_ata6:
                        break;
                case controller_kl_ata4:
                        tm = mdma_timings_66;
                        break;
                case controller_kl_ata3:
                        tm = mdma_timings_33k;
                        break;
                default:
                        tm = mdma_timings_33;
                        break;
        }
        if (tm != NULL) {
                /* Lookup matching access & recovery times */
                i = -1;
                for (;;) {
                        if (tm[i+1].cycleTime < cycleTime)
                                break;
                        i++;
                }
                cycleTime = tm[i].cycleTime;
                accessTime = tm[i].accessTime;
                recTime = tm[i].recoveryTime;

#ifdef IDE_PMAC_DEBUG
                printk(KERN_ERR "%s: MDMA, cycleTime: %d, accessTime: %d, recTime: %d\n",
                        drive->name, cycleTime, accessTime, recTime);
#endif
        }
        switch(intf_type) {
        case controller_sh_ata6: {
                /* 133Mhz cell */
                u32 tr = kauai_lookup_timing(shasta_mdma_timings, cycleTime);
                *timings = ((*timings) & ~TR_133_PIOREG_MDMA_MASK) | tr;
                *timings2 = (*timings2) & ~TR_133_UDMAREG_UDMA_EN;
                }
        case controller_un_ata6:
        case controller_k2_ata6: {
                /* 100Mhz cell */
                u32 tr = kauai_lookup_timing(kauai_mdma_timings, cycleTime);
                *timings = ((*timings) & ~TR_100_PIOREG_MDMA_MASK) | tr;
                *timings2 = (*timings2) & ~TR_100_UDMAREG_UDMA_EN;
                }
                break;
        case controller_kl_ata4:
                /* 66Mhz cell */
                accessTicks = SYSCLK_TICKS_66(accessTime);
                accessTicks = min(accessTicks, 0x1fU);
                accessTicks = max(accessTicks, 0x1U);
                recTicks = SYSCLK_TICKS_66(recTime);
                recTicks = min(recTicks, 0x1fU);
                recTicks = max(recTicks, 0x3U);
                /* Clear out mdma bits and disable udma */
                *timings = ((*timings) & ~(TR_66_MDMA_MASK | TR_66_UDMA_MASK)) |
                        (accessTicks << TR_66_MDMA_ACCESS_SHIFT) |
                        (recTicks << TR_66_MDMA_RECOVERY_SHIFT);
                break;
        case controller_kl_ata3:
                /* 33Mhz cell on KeyLargo */
                accessTicks = SYSCLK_TICKS(accessTime);
                accessTicks = max(accessTicks, 1U);
                accessTicks = min(accessTicks, 0x1fU);
                accessTime = accessTicks * IDE_SYSCLK_NS;
                recTicks = SYSCLK_TICKS(recTime);
                recTicks = max(recTicks, 1U);
                recTicks = min(recTicks, 0x1fU);
                *timings = ((*timings) & ~TR_33_MDMA_MASK) |
                                (accessTicks << TR_33_MDMA_ACCESS_SHIFT) |
                                (recTicks << TR_33_MDMA_RECOVERY_SHIFT);
                break;
        default: {
                /* 33Mhz cell on others */
                int halfTick = 0;
                int origAccessTime = accessTime;
                int origRecTime = recTime;
                
                accessTicks = SYSCLK_TICKS(accessTime);
                accessTicks = max(accessTicks, 1U);
                accessTicks = min(accessTicks, 0x1fU);
                accessTime = accessTicks * IDE_SYSCLK_NS;
                recTicks = SYSCLK_TICKS(recTime);
                recTicks = max(recTicks, 2U) - 1;
                recTicks = min(recTicks, 0x1fU);
                recTime = (recTicks + 1) * IDE_SYSCLK_NS;
                if ((accessTicks > 1) &&
                    ((accessTime - IDE_SYSCLK_NS/2) >= origAccessTime) &&
                    ((recTime - IDE_SYSCLK_NS/2) >= origRecTime)) {
                        halfTick = 1;
                        accessTicks--;
                }
                *timings = ((*timings) & ~TR_33_MDMA_MASK) |
                                (accessTicks << TR_33_MDMA_ACCESS_SHIFT) |
                                (recTicks << TR_33_MDMA_RECOVERY_SHIFT);
                if (halfTick)
                        *timings |= TR_33_MDMA_HALFTICK;
                }
        }
#ifdef IDE_PMAC_DEBUG
        printk(KERN_ERR "%s: Set MDMA timing for mode %d, reg: 0x%08x\n",
                drive->name, speed & 0xf,  *timings);
#endif  
}
#endif /* #ifdef CONFIG_BLK_DEV_IDEDMA_PMAC */

/* 
 * Speedproc. This function is called by the core to set any of the standard
 * DMA timing (MDMA or UDMA) to both the drive and the controller.
 */
static int pmac_ide_tune_chipset(ide_drive_t *drive, const u8 speed)
{
        int unit = (drive->select.b.unit & 0x01);
        int ret = 0;
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)HWIF(drive)->hwif_data;
        u32 *timings, *timings2, tl[2];

        timings = &pmif->timings[unit];
        timings2 = &pmif->timings[unit+2];

        /* Copy timings to local image */
        tl[0] = *timings;
        tl[1] = *timings2;

        switch(speed) {
#ifdef CONFIG_BLK_DEV_IDEDMA_PMAC
                case XFER_UDMA_6:
                case XFER_UDMA_5:
                case XFER_UDMA_4:
                case XFER_UDMA_3:
                case XFER_UDMA_2:
                case XFER_UDMA_1:
                case XFER_UDMA_0:
                        if (pmif->kind == controller_kl_ata4)
                                ret = set_timings_udma_ata4(&tl[0], speed);
                        else if (pmif->kind == controller_un_ata6
                                 || pmif->kind == controller_k2_ata6)
                                ret = set_timings_udma_ata6(&tl[0], &tl[1], speed);
                        else if (pmif->kind == controller_sh_ata6)
                                ret = set_timings_udma_shasta(&tl[0], &tl[1], speed);
                        else
                                ret = 1;
                        break;
                case XFER_MW_DMA_2:
                case XFER_MW_DMA_1:
                case XFER_MW_DMA_0:
                        set_timings_mdma(drive, pmif->kind, &tl[0], &tl[1], speed);
                        break;
                case XFER_SW_DMA_2:
                case XFER_SW_DMA_1:
                case XFER_SW_DMA_0:
                        return 1;
#endif /* CONFIG_BLK_DEV_IDEDMA_PMAC */
                default:
                        ret = 1;
        }
        if (ret)
                return ret;

        ret = pmac_ide_do_setfeature(drive, speed);
        if (ret)
                return ret;

        /* Apply timings to controller */
        *timings = tl[0];
        *timings2 = tl[1];

        pmac_ide_do_update_timings(drive);      

        return 0;
}

/*
 * Blast some well known "safe" values to the timing registers at init or
 * wakeup from sleep time, before we do real calculation
 */
static void
sanitize_timings(pmac_ide_hwif_t *pmif)
{
        unsigned int value, value2 = 0;
        
        switch(pmif->kind) {
                case controller_sh_ata6:
                        value = 0x0a820c97;
                        value2 = 0x00033031;
                        break;
                case controller_un_ata6:
                case controller_k2_ata6:
                        value = 0x08618a92;
                        value2 = 0x00002921;
                        break;
                case controller_kl_ata4:
                        value = 0x0008438c;
                        break;
                case controller_kl_ata3:
                        value = 0x00084526;
                        break;
                case controller_heathrow:
                case controller_ohare:
                default:
                        value = 0x00074526;
                        break;
        }
        pmif->timings[0] = pmif->timings[1] = value;
        pmif->timings[2] = pmif->timings[3] = value2;
}

unsigned long
pmac_ide_get_base(int index)
{
        return pmac_ide[index].regbase;
}

int
pmac_ide_check_base(unsigned long base)
{
        int ix;
        
        for (ix = 0; ix < MAX_HWIFS; ++ix)
                if (base == pmac_ide[ix].regbase)
                        return ix;
        return -1;
}

int
pmac_ide_get_irq(unsigned long base)
{
        int ix;

        for (ix = 0; ix < MAX_HWIFS; ++ix)
                if (base == pmac_ide[ix].regbase)
                        return pmac_ide[ix].irq;
        return 0;
}

static int ide_majors[] = { 3, 22, 33, 34, 56, 57 };

dev_t __init
pmac_find_ide_boot(char *bootdevice, int n)
{
        int i;
        
        /*
         * Look through the list of IDE interfaces for this one.
         */
        for (i = 0; i < pmac_ide_count; ++i) {
                char *name;
                if (!pmac_ide[i].node || !pmac_ide[i].node->full_name)
                        continue;
                name = pmac_ide[i].node->full_name;
                if (memcmp(name, bootdevice, n) == 0 && name[n] == 0) {
                        /* XXX should cope with the 2nd drive as well... */
                        return MKDEV(ide_majors[i], 0);
                }
        }

        return 0;
}

/* Suspend call back, should be called after the child devices
 * have actually been suspended
 */
static int
pmac_ide_do_suspend(ide_hwif_t *hwif)
{
        pmac_ide_hwif_t *pmif = (pmac_ide_hwif_t *)hwif->hwif_data;
        
        /* We clear the timings */
        pmif->timings[0] = 0;
        pmif->timings[1] = 0;
        
        disable_irq(pmif->irq);

        /* The media bay will handle itself just fine */
        if (pmif->mediabay)
                return 0;
        
        /* Kauai has bus control FCRs directly here */
        if (pmif->kauai_fcr) {
                u32 fcr = readl(pmif->kauai_fcr);
                fcr &= ~(KAUAI_FCR_UATA_RESET_N | KAUAI_FCR_UATA_ENABLE);
                writel(fcr, pmif->kauai_fcr);
        }

        /* Disable the bus on older machines and the cell on kauai */
        ppc_md.feature_call(PMAC_FTR_IDE_ENABLE, pmif->node, pmif->aapl_bus_id,
                            0);

        return 0;
}

/* Resume call back, should be called before the child devices
 * are resumed
 */
static int
pmac_ide_do_resume(ide_hwif_t *hwif)
{
        pmac_ide_hwif_t *pmif = (pmac_ide_hwif_t *)hwif->hwif_data;
        
        /* Hard reset & re-enable controller (do we really need to reset ? -BenH) */
        if (!pmif->mediabay) {
                ppc_md.feature_call(PMAC_FTR_IDE_RESET, pmif->node, pmif->aapl_bus_id, 1);
                ppc_md.feature_call(PMAC_FTR_IDE_ENABLE, pmif->node, pmif->aapl_bus_id, 1);
                msleep(10);
                ppc_md.feature_call(PMAC_FTR_IDE_RESET, pmif->node, pmif->aapl_bus_id, 0);

                /* Kauai has it different */
                if (pmif->kauai_fcr) {
                        u32 fcr = readl(pmif->kauai_fcr);
                        fcr |= KAUAI_FCR_UATA_RESET_N | KAUAI_FCR_UATA_ENABLE;
                        writel(fcr, pmif->kauai_fcr);
                }

                msleep(jiffies_to_msecs(IDE_WAKEUP_DELAY));
        }

        /* Sanitize drive timings */
        sanitize_timings(pmif);

        enable_irq(pmif->irq);

        return 0;
}

/*
 * Setup, register & probe an IDE channel driven by this driver, this is
 * called by one of the 2 probe functions (macio or PCI). Note that a channel
 * that ends up beeing free of any device is not kept around by this driver
 * (it is kept in 2.4). This introduce an interface numbering change on some
 * rare machines unfortunately, but it's better this way.
 */
static int
pmac_ide_setup_device(pmac_ide_hwif_t *pmif, ide_hwif_t *hwif)
{
        struct device_node *np = pmif->node;
        const int *bidp;

        pmif->cable_80 = 0;
        pmif->broken_dma = pmif->broken_dma_warn = 0;
        if (of_device_is_compatible(np, "shasta-ata"))
                pmif->kind = controller_sh_ata6;
        else if (of_device_is_compatible(np, "kauai-ata"))
                pmif->kind = controller_un_ata6;
        else if (of_device_is_compatible(np, "K2-UATA"))
                pmif->kind = controller_k2_ata6;
        else if (of_device_is_compatible(np, "keylargo-ata")) {
                if (strcmp(np->name, "ata-4") == 0)
                        pmif->kind = controller_kl_ata4;
                else
                        pmif->kind = controller_kl_ata3;
        } else if (of_device_is_compatible(np, "heathrow-ata"))
                pmif->kind = controller_heathrow;
        else {
                pmif->kind = controller_ohare;
                pmif->broken_dma = 1;
        }

        bidp = of_get_property(np, "AAPL,bus-id", NULL);
        pmif->aapl_bus_id =  bidp ? *bidp : 0;

        /* Get cable type from device-tree */
        if (pmif->kind == controller_kl_ata4 || pmif->kind == controller_un_ata6
            || pmif->kind == controller_k2_ata6
            || pmif->kind == controller_sh_ata6) {
                const char* cable = of_get_property(np, "cable-type", NULL);
                if (cable && !strncmp(cable, "80-", 3))
                        pmif->cable_80 = 1;
        }
        /* G5's seem to have incorrect cable type in device-tree. Let's assume
         * they have a 80 conductor cable, this seem to be always the case unless
         * the user mucked around
         */
        if (of_device_is_compatible(np, "K2-UATA") ||
            of_device_is_compatible(np, "shasta-ata"))
                pmif->cable_80 = 1;

        /* On Kauai-type controllers, we make sure the FCR is correct */
        if (pmif->kauai_fcr)
                writel(KAUAI_FCR_UATA_MAGIC |
                       KAUAI_FCR_UATA_RESET_N |
                       KAUAI_FCR_UATA_ENABLE, pmif->kauai_fcr);

        pmif->mediabay = 0;
        
        /* Make sure we have sane timings */
        sanitize_timings(pmif);

#ifndef CONFIG_PPC64
        /* XXX FIXME: Media bay stuff need re-organizing */
        if (np->parent && np->parent->name
            && strcasecmp(np->parent->name, "media-bay") == 0) {
#ifdef CONFIG_PMAC_MEDIABAY
                media_bay_set_ide_infos(np->parent, pmif->regbase, pmif->irq, hwif->index);
#endif /* CONFIG_PMAC_MEDIABAY */
                pmif->mediabay = 1;
                if (!bidp)
                        pmif->aapl_bus_id = 1;
        } else if (pmif->kind == controller_ohare) {
                /* The code below is having trouble on some ohare machines
                 * (timing related ?). Until I can put my hand on one of these
                 * units, I keep the old way
                 */
                ppc_md.feature_call(PMAC_FTR_IDE_ENABLE, np, 0, 1);
        } else
#endif
        {
                /* This is necessary to enable IDE when net-booting */
                ppc_md.feature_call(PMAC_FTR_IDE_RESET, np, pmif->aapl_bus_id, 1);
                ppc_md.feature_call(PMAC_FTR_IDE_ENABLE, np, pmif->aapl_bus_id, 1);
                msleep(10);
                ppc_md.feature_call(PMAC_FTR_IDE_RESET, np, pmif->aapl_bus_id, 0);
                msleep(jiffies_to_msecs(IDE_WAKEUP_DELAY));
        }

        /* Setup MMIO ops */
        default_hwif_mmiops(hwif);
        hwif->OUTBSYNC = pmac_outbsync;

        /* Tell common code _not_ to mess with resources */
        hwif->mmio = 1;
        hwif->hwif_data = pmif;
        pmac_ide_init_hwif_ports(&hwif->hw, pmif->regbase, 0, &hwif->irq);
        memcpy(hwif->io_ports, hwif->hw.io_ports, sizeof(hwif->io_ports));
        hwif->chipset = ide_pmac;
        hwif->noprobe = !hwif->io_ports[IDE_DATA_OFFSET] || pmif->mediabay;
        hwif->hold = pmif->mediabay;
        hwif->cbl = pmif->cable_80 ? ATA_CBL_PATA80 : ATA_CBL_PATA40;
        hwif->drives[0].unmask = 1;
        hwif->drives[1].unmask = 1;
        hwif->pio_mask = ATA_PIO4;
        hwif->set_pio_mode = pmac_ide_set_pio_mode;
        if (pmif->kind == controller_un_ata6
            || pmif->kind == controller_k2_ata6
            || pmif->kind == controller_sh_ata6)
                hwif->selectproc = pmac_ide_kauai_selectproc;
        else
                hwif->selectproc = pmac_ide_selectproc;
        hwif->speedproc = pmac_ide_tune_chipset;

        printk(KERN_INFO "ide%d: Found Apple %s controller, bus ID %d%s, irq %d\n",
               hwif->index, model_name[pmif->kind], pmif->aapl_bus_id,
               pmif->mediabay ? " (mediabay)" : "", hwif->irq);
                        
#ifdef CONFIG_PMAC_MEDIABAY
        if (pmif->mediabay && check_media_bay_by_base(pmif->regbase, MB_CD) == 0)
                hwif->noprobe = 0;
#endif /* CONFIG_PMAC_MEDIABAY */

        hwif->sg_max_nents = MAX_DCMDS;

#ifdef CONFIG_BLK_DEV_IDEDMA_PMAC
        /* has a DBDMA controller channel */
        if (pmif->dma_regs)
                pmac_ide_setup_dma(pmif, hwif);
#endif /* CONFIG_BLK_DEV_IDEDMA_PMAC */

        /* We probe the hwif now */
        probe_hwif_init(hwif);

        ide_proc_register_port(hwif);

        return 0;
}

/*
 * Attach to a macio probed interface
 */
static int __devinit
pmac_ide_macio_attach(struct macio_dev *mdev, const struct of_device_id *match)
{
        void __iomem *base;
        unsigned long regbase;
        int irq;
        ide_hwif_t *hwif;
        pmac_ide_hwif_t *pmif;
        int i, rc;

        i = 0;
        while (i < MAX_HWIFS && (ide_hwifs[i].io_ports[IDE_DATA_OFFSET] != 0
            || pmac_ide[i].node != NULL))
                ++i;
        if (i >= MAX_HWIFS) {
                printk(KERN_ERR "ide-pmac: MacIO interface attach with no slot\n");
                printk(KERN_ERR "          %s\n", mdev->ofdev.node->full_name);
                return -ENODEV;
        }

        pmif = &pmac_ide[i];
        hwif = &ide_hwifs[i];

        if (macio_resource_count(mdev) == 0) {
                printk(KERN_WARNING "ide%d: no address for %s\n",
                       i, mdev->ofdev.node->full_name);
                return -ENXIO;
        }

        /* Request memory resource for IO ports */
        if (macio_request_resource(mdev, 0, "ide-pmac (ports)")) {
                printk(KERN_ERR "ide%d: can't request mmio resource !\n", i);
                return -EBUSY;
        }
                        
        /* XXX This is bogus. Should be fixed in the registry by checking
         * the kind of host interrupt controller, a bit like gatwick
         * fixes in irq.c. That works well enough for the single case
         * where that happens though...
         */
        if (macio_irq_count(mdev) == 0) {
                printk(KERN_WARNING "ide%d: no intrs for device %s, using 13\n",
                        i, mdev->ofdev.node->full_name);
                irq = irq_create_mapping(NULL, 13);
        } else
                irq = macio_irq(mdev, 0);

        base = ioremap(macio_resource_start(mdev, 0), 0x400);
        regbase = (unsigned long) base;

        hwif->pci_dev = mdev->bus->pdev;
        hwif->gendev.parent = &mdev->ofdev.dev;

        pmif->mdev = mdev;
        pmif->node = mdev->ofdev.node;
        pmif->regbase = regbase;
        pmif->irq = irq;
        pmif->kauai_fcr = NULL;
#ifdef CONFIG_BLK_DEV_IDEDMA_PMAC
        if (macio_resource_count(mdev) >= 2) {
                if (macio_request_resource(mdev, 1, "ide-pmac (dma)"))
                        printk(KERN_WARNING "ide%d: can't request DMA resource !\n", i);
                else
                        pmif->dma_regs = ioremap(macio_resource_start(mdev, 1), 0x1000);
        } else
                pmif->dma_regs = NULL;
#endif /* CONFIG_BLK_DEV_IDEDMA_PMAC */
        dev_set_drvdata(&mdev->ofdev.dev, hwif);

        rc = pmac_ide_setup_device(pmif, hwif);
        if (rc != 0) {
                /* The inteface is released to the common IDE layer */
                dev_set_drvdata(&mdev->ofdev.dev, NULL);
                iounmap(base);
                if (pmif->dma_regs)
                        iounmap(pmif->dma_regs);
                memset(pmif, 0, sizeof(*pmif));
                macio_release_resource(mdev, 0);
                if (pmif->dma_regs)
                        macio_release_resource(mdev, 1);
        }

        return rc;
}

static int
pmac_ide_macio_suspend(struct macio_dev *mdev, pm_message_t mesg)
{
        ide_hwif_t      *hwif = (ide_hwif_t *)dev_get_drvdata(&mdev->ofdev.dev);
        int             rc = 0;

        if (mesg.event != mdev->ofdev.dev.power.power_state.event
                        && mesg.event == PM_EVENT_SUSPEND) {
                rc = pmac_ide_do_suspend(hwif);
                if (rc == 0)
                        mdev->ofdev.dev.power.power_state = mesg;
        }

        return rc;
}

static int
pmac_ide_macio_resume(struct macio_dev *mdev)
{
        ide_hwif_t      *hwif = (ide_hwif_t *)dev_get_drvdata(&mdev->ofdev.dev);
        int             rc = 0;
        
        if (mdev->ofdev.dev.power.power_state.event != PM_EVENT_ON) {
                rc = pmac_ide_do_resume(hwif);
                if (rc == 0)
                        mdev->ofdev.dev.power.power_state = PMSG_ON;
        }

        return rc;
}

/*
 * Attach to a PCI probed interface
 */
static int __devinit
pmac_ide_pci_attach(struct pci_dev *pdev, const struct pci_device_id *id)
{
        ide_hwif_t *hwif;
        struct device_node *np;
        pmac_ide_hwif_t *pmif;
        void __iomem *base;
        unsigned long rbase, rlen;
        int i, rc;

        np = pci_device_to_OF_node(pdev);
        if (np == NULL) {
                printk(KERN_ERR "ide-pmac: cannot find MacIO node for Kauai ATA interface\n");
                return -ENODEV;
        }
        i = 0;
        while (i < MAX_HWIFS && (ide_hwifs[i].io_ports[IDE_DATA_OFFSET] != 0
            || pmac_ide[i].node != NULL))
                ++i;
        if (i >= MAX_HWIFS) {
                printk(KERN_ERR "ide-pmac: PCI interface attach with no slot\n");
                printk(KERN_ERR "          %s\n", np->full_name);
                return -ENODEV;
        }

        pmif = &pmac_ide[i];
        hwif = &ide_hwifs[i];

        if (pci_enable_device(pdev)) {
                printk(KERN_WARNING "ide%i: Can't enable PCI device for %s\n",
                        i, np->full_name);
                return -ENXIO;
        }
        pci_set_master(pdev);
                        
        if (pci_request_regions(pdev, "Kauai ATA")) {
                printk(KERN_ERR "ide%d: Cannot obtain PCI resources for %s\n",
                        i, np->full_name);
                return -ENXIO;
        }

        hwif->pci_dev = pdev;
        hwif->gendev.parent = &pdev->dev;
        pmif->mdev = NULL;
        pmif->node = np;

        rbase = pci_resource_start(pdev, 0);
        rlen = pci_resource_len(pdev, 0);

        base = ioremap(rbase, rlen);
        pmif->regbase = (unsigned long) base + 0x2000;
#ifdef CONFIG_BLK_DEV_IDEDMA_PMAC
        pmif->dma_regs = base + 0x1000;
#endif /* CONFIG_BLK_DEV_IDEDMA_PMAC */
        pmif->kauai_fcr = base;
        pmif->irq = pdev->irq;

        pci_set_drvdata(pdev, hwif);

        rc = pmac_ide_setup_device(pmif, hwif);
        if (rc != 0) {
                /* The inteface is released to the common IDE layer */
                pci_set_drvdata(pdev, NULL);
                iounmap(base);
                memset(pmif, 0, sizeof(*pmif));
                pci_release_regions(pdev);
        }

        return rc;
}

static int
pmac_ide_pci_suspend(struct pci_dev *pdev, pm_message_t mesg)
{
        ide_hwif_t      *hwif = (ide_hwif_t *)pci_get_drvdata(pdev);
        int             rc = 0;
        
        if (mesg.event != pdev->dev.power.power_state.event
                        && mesg.event == PM_EVENT_SUSPEND) {
                rc = pmac_ide_do_suspend(hwif);
                if (rc == 0)
                        pdev->dev.power.power_state = mesg;
        }

        return rc;
}

static int
pmac_ide_pci_resume(struct pci_dev *pdev)
{
        ide_hwif_t      *hwif = (ide_hwif_t *)pci_get_drvdata(pdev);
        int             rc = 0;
        
        if (pdev->dev.power.power_state.event != PM_EVENT_ON) {
                rc = pmac_ide_do_resume(hwif);
                if (rc == 0)
                        pdev->dev.power.power_state = PMSG_ON;
        }

        return rc;
}

static struct of_device_id pmac_ide_macio_match[] = 
{
        {
        .name           = "IDE",
        },
        {
        .name           = "ATA",
        },
        {
        .type           = "ide",
        },
        {
        .type           = "ata",
        },
        {},
};

static struct macio_driver pmac_ide_macio_driver = 
{
        .name           = "ide-pmac",
        .match_table    = pmac_ide_macio_match,
        .probe          = pmac_ide_macio_attach,
        .suspend        = pmac_ide_macio_suspend,
        .resume         = pmac_ide_macio_resume,
};

static struct pci_device_id pmac_ide_pci_match[] = {
        { PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_UNI_N_ATA,
          PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
        { PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_IPID_ATA100,
          PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
        { PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_K2_ATA100,
          PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
        { PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_SH_ATA,
          PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
        { PCI_VENDOR_ID_APPLE, PCI_DEVICE_ID_APPLE_IPID2_ATA,
          PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
        {},
};

static struct pci_driver pmac_ide_pci_driver = {
        .name           = "ide-pmac",
        .id_table       = pmac_ide_pci_match,
        .probe          = pmac_ide_pci_attach,
        .suspend        = pmac_ide_pci_suspend,
        .resume         = pmac_ide_pci_resume,
};
MODULE_DEVICE_TABLE(pci, pmac_ide_pci_match);

int __init pmac_ide_probe(void)
{
        int error;

        if (!machine_is(powermac))
                return -ENODEV;

#ifdef CONFIG_BLK_DEV_IDE_PMAC_ATA100FIRST
        error = pci_register_driver(&pmac_ide_pci_driver);
        if (error)
                goto out;
        error = macio_register_driver(&pmac_ide_macio_driver);
        if (error) {
                pci_unregister_driver(&pmac_ide_pci_driver);
                goto out;
        }
#else
        error = macio_register_driver(&pmac_ide_macio_driver);
        if (error)
                goto out;
        error = pci_register_driver(&pmac_ide_pci_driver);
        if (error) {
                macio_unregister_driver(&pmac_ide_macio_driver);
                goto out;
        }
#endif
out:
        return error;
}

#ifdef CONFIG_BLK_DEV_IDEDMA_PMAC

/*
 * pmac_ide_build_dmatable builds the DBDMA command list
 * for a transfer and sets the DBDMA channel to point to it.
 */
static int
pmac_ide_build_dmatable(ide_drive_t *drive, struct request *rq)
{
        struct dbdma_cmd *table;
        int i, count = 0;
        ide_hwif_t *hwif = HWIF(drive);
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)hwif->hwif_data;
        volatile struct dbdma_regs __iomem *dma = pmif->dma_regs;
        struct scatterlist *sg;
        int wr = (rq_data_dir(rq) == WRITE);

        /* DMA table is already aligned */
        table = (struct dbdma_cmd *) pmif->dma_table_cpu;

        /* Make sure DMA controller is stopped (necessary ?) */
        writel((RUN|PAUSE|FLUSH|WAKE|DEAD) << 16, &dma->control);
        while (readl(&dma->status) & RUN)
                udelay(1);

        hwif->sg_nents = i = ide_build_sglist(drive, rq);

        if (!i)
                return 0;

        /* Build DBDMA commands list */
        sg = hwif->sg_table;
        while (i && sg_dma_len(sg)) {
                u32 cur_addr;
                u32 cur_len;

                cur_addr = sg_dma_address(sg);
                cur_len = sg_dma_len(sg);

                if (pmif->broken_dma && cur_addr & (L1_CACHE_BYTES - 1)) {
                        if (pmif->broken_dma_warn == 0) {
                                printk(KERN_WARNING "%s: DMA on non aligned address,"
                                       "switching to PIO on Ohare chipset\n", drive->name);
                                pmif->broken_dma_warn = 1;
                        }
                        goto use_pio_instead;
                }
                while (cur_len) {
                        unsigned int tc = (cur_len < 0xfe00)? cur_len: 0xfe00;

                        if (count++ >= MAX_DCMDS) {
                                printk(KERN_WARNING "%s: DMA table too small\n",
                                       drive->name);
                                goto use_pio_instead;
                        }
                        st_le16(&table->command, wr? OUTPUT_MORE: INPUT_MORE);
                        st_le16(&table->req_count, tc);
                        st_le32(&table->phy_addr, cur_addr);
                        table->cmd_dep = 0;
                        table->xfer_status = 0;
                        table->res_count = 0;
                        cur_addr += tc;
                        cur_len -= tc;
                        ++table;
                }
                sg++;
                i--;
        }

        /* convert the last command to an input/output last command */
        if (count) {
                st_le16(&table[-1].command, wr? OUTPUT_LAST: INPUT_LAST);
                /* add the stop command to the end of the list */
                memset(table, 0, sizeof(struct dbdma_cmd));
                st_le16(&table->command, DBDMA_STOP);
                mb();
                writel(hwif->dmatable_dma, &dma->cmdptr);
                return 1;
        }

        printk(KERN_DEBUG "%s: empty DMA table?\n", drive->name);
 use_pio_instead:
        pci_unmap_sg(hwif->pci_dev,
                     hwif->sg_table,
                     hwif->sg_nents,
                     hwif->sg_dma_direction);
        return 0; /* revert to PIO for this request */
}

/* Teardown mappings after DMA has completed.  */
static void
pmac_ide_destroy_dmatable (ide_drive_t *drive)
{
        ide_hwif_t *hwif = drive->hwif;
        struct pci_dev *dev = HWIF(drive)->pci_dev;
        struct scatterlist *sg = hwif->sg_table;
        int nents = hwif->sg_nents;

        if (nents) {
                pci_unmap_sg(dev, sg, nents, hwif->sg_dma_direction);
                hwif->sg_nents = 0;
        }
}

/*
 * Check what is the best DMA timing setting for the drive and
 * call appropriate functions to apply it.
 */
static int
pmac_ide_dma_check(ide_drive_t *drive)
{
        int enable = 1;

        drive->using_dma = 0;
        
        if (drive->media == ide_floppy)
                enable = 0;
        if ((drive->id->capability & 1) == 0 && !__ide_dma_good_drive(drive))
                enable = 0;
        if (__ide_dma_bad_drive(drive))
                enable = 0;

        if (enable) {
                u8 mode = ide_max_dma_mode(drive);

                if (mode && pmac_ide_tune_chipset(drive, mode) == 0)
                        drive->using_dma = 1;
        }
        return 0;
}

/*
 * Prepare a DMA transfer. We build the DMA table, adjust the timings for
 * a read on KeyLargo ATA/66 and mark us as waiting for DMA completion
 */
static int
pmac_ide_dma_setup(ide_drive_t *drive)
{
        ide_hwif_t *hwif = HWIF(drive);
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)hwif->hwif_data;
        struct request *rq = HWGROUP(drive)->rq;
        u8 unit = (drive->select.b.unit & 0x01);
        u8 ata4;

        if (pmif == NULL)
                return 1;
        ata4 = (pmif->kind == controller_kl_ata4);      

        if (!pmac_ide_build_dmatable(drive, rq)) {
                ide_map_sg(drive, rq);
                return 1;
        }

        /* Apple adds 60ns to wrDataSetup on reads */
        if (ata4 && (pmif->timings[unit] & TR_66_UDMA_EN)) {
                writel(pmif->timings[unit] + (!rq_data_dir(rq) ? 0x00800000UL : 0),
                        PMAC_IDE_REG(IDE_TIMING_CONFIG));
                (void)readl(PMAC_IDE_REG(IDE_TIMING_CONFIG));
        }

        drive->waiting_for_dma = 1;

        return 0;
}

static void
pmac_ide_dma_exec_cmd(ide_drive_t *drive, u8 command)
{
        /* issue cmd to drive */
        ide_execute_command(drive, command, &ide_dma_intr, 2*WAIT_CMD, NULL);
}

/*
 * Kick the DMA controller into life after the DMA command has been issued
 * to the drive.
 */
static void
pmac_ide_dma_start(ide_drive_t *drive)
{
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)HWIF(drive)->hwif_data;
        volatile struct dbdma_regs __iomem *dma;

        dma = pmif->dma_regs;

        writel((RUN << 16) | RUN, &dma->control);
        /* Make sure it gets to the controller right now */
        (void)readl(&dma->control);
}

/*
 * After a DMA transfer, make sure the controller is stopped
 */
static int
pmac_ide_dma_end (ide_drive_t *drive)
{
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)HWIF(drive)->hwif_data;
        volatile struct dbdma_regs __iomem *dma;
        u32 dstat;
        
        if (pmif == NULL)
                return 0;
        dma = pmif->dma_regs;

        drive->waiting_for_dma = 0;
        dstat = readl(&dma->status);
        writel(((RUN|WAKE|DEAD) << 16), &dma->control);
        pmac_ide_destroy_dmatable(drive);
        /* verify good dma status. we don't check for ACTIVE beeing 0. We should...
         * in theory, but with ATAPI decices doing buffer underruns, that would
         * cause us to disable DMA, which isn't what we want
         */
        return (dstat & (RUN|DEAD)) != RUN;
}

/*
 * Check out that the interrupt we got was for us. We can't always know this
 * for sure with those Apple interfaces (well, we could on the recent ones but
 * that's not implemented yet), on the other hand, we don't have shared interrupts
 * so it's not really a problem
 */
static int
pmac_ide_dma_test_irq (ide_drive_t *drive)
{
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)HWIF(drive)->hwif_data;
        volatile struct dbdma_regs __iomem *dma;
        unsigned long status, timeout;

        if (pmif == NULL)
                return 0;
        dma = pmif->dma_regs;

        /* We have to things to deal with here:
         * 
         * - The dbdma won't stop if the command was started
         * but completed with an error without transferring all
         * datas. This happens when bad blocks are met during
         * a multi-block transfer.
         * 
         * - The dbdma fifo hasn't yet finished flushing to
         * to system memory when the disk interrupt occurs.
         * 
         */

        /* If ACTIVE is cleared, the STOP command have passed and
         * transfer is complete.
         */
        status = readl(&dma->status);
        if (!(status & ACTIVE))
                return 1;
        if (!drive->waiting_for_dma)
                printk(KERN_WARNING "ide%d, ide_dma_test_irq \
                        called while not waiting\n", HWIF(drive)->index);

        /* If dbdma didn't execute the STOP command yet, the
         * active bit is still set. We consider that we aren't
         * sharing interrupts (which is hopefully the case with
         * those controllers) and so we just try to flush the
         * channel for pending data in the fifo
         */
        udelay(1);
        writel((FLUSH << 16) | FLUSH, &dma->control);
        timeout = 0;
        for (;;) {
                udelay(1);
                status = readl(&dma->status);
                if ((status & FLUSH) == 0)
                        break;
                if (++timeout > 100) {
                        printk(KERN_WARNING "ide%d, ide_dma_test_irq \
                        timeout flushing channel\n", HWIF(drive)->index);
                        break;
                }
        }       
        return 1;
}

static void pmac_ide_dma_host_off(ide_drive_t *drive)
{
}

static void pmac_ide_dma_host_on(ide_drive_t *drive)
{
}

static void
pmac_ide_dma_lost_irq (ide_drive_t *drive)
{
        pmac_ide_hwif_t* pmif = (pmac_ide_hwif_t *)HWIF(drive)->hwif_data;
        volatile struct dbdma_regs __iomem *dma;
        unsigned long status;

        if (pmif == NULL)
                return;
        dma = pmif->dma_regs;

        status = readl(&dma->status);
        printk(KERN_ERR "ide-pmac lost interrupt, dma status: %lx\n", status);
}

/*
 * Allocate the data structures needed for using DMA with an interface
 * and fill the proper list of functions pointers
 */
static void __init 
pmac_ide_setup_dma(pmac_ide_hwif_t *pmif, ide_hwif_t *hwif)
{
        /* We won't need pci_dev if we switch to generic consistent
         * DMA routines ...
         */
        if (hwif->pci_dev == NULL)
                return;
        /*
         * Allocate space for the DBDMA commands.
         * The +2 is +1 for the stop command and +1 to allow for
         * aligning the start address to a multiple of 16 bytes.
         */
        pmif->dma_table_cpu = (struct dbdma_cmd*)pci_alloc_consistent(
                hwif->pci_dev,
                (MAX_DCMDS + 2) * sizeof(struct dbdma_cmd),
                &hwif->dmatable_dma);
        if (pmif->dma_table_cpu == NULL) {
                printk(KERN_ERR "%s: unable to allocate DMA command list\n",
                       hwif->name);
                return;
        }

        hwif->dma_off_quietly = &ide_dma_off_quietly;
        hwif->ide_dma_on = &__ide_dma_on;
        hwif->ide_dma_check = &pmac_ide_dma_check;
        hwif->dma_setup = &pmac_ide_dma_setup;
        hwif->dma_exec_cmd = &pmac_ide_dma_exec_cmd;
        hwif->dma_start = &pmac_ide_dma_start;
        hwif->ide_dma_end = &pmac_ide_dma_end;
        hwif->ide_dma_test_irq = &pmac_ide_dma_test_irq;
        hwif->dma_host_off = &pmac_ide_dma_host_off;
        hwif->dma_host_on = &pmac_ide_dma_host_on;
        hwif->dma_timeout = &ide_dma_timeout;
        hwif->dma_lost_irq = &pmac_ide_dma_lost_irq;

        hwif->atapi_dma = 1;
        switch(pmif->kind) {
                case controller_sh_ata6:
                        hwif->ultra_mask = pmif->cable_80 ? 0x7f : 0x07;
                        hwif->mwdma_mask = 0x07;
                        hwif->swdma_mask = 0x00;
                        break;
                case controller_un_ata6:
                case controller_k2_ata6:
                        hwif->ultra_mask = pmif->cable_80 ? 0x3f : 0x07;
                        hwif->mwdma_mask = 0x07;
                        hwif->swdma_mask = 0x00;
                        break;
                case controller_kl_ata4:
                        hwif->ultra_mask = pmif->cable_80 ? 0x1f : 0x07;
                        hwif->mwdma_mask = 0x07;
                        hwif->swdma_mask = 0x00;
                        break;
                default:
                        hwif->ultra_mask = 0x00;
                        hwif->mwdma_mask = 0x07;
                        hwif->swdma_mask = 0x00;
                        break;
        }       
}

#endif /* CONFIG_BLK_DEV_IDEDMA_PMAC */