[PATCH] ide: it8212 backport for Bartlomiej IDE

This lets you throw out the iteraid stuff that has ended up back in due
to stupid goings on in the IDE world. Its the same heavily tested code
shipped in Fedora/Red Hat products but without the other dependancies on
the Bartlomiej IDE layer.

Pre-requisite: the ide-disk patch I sent to handle pure LBA devices.

Obviously you lose things like hot unplug with the Bartlomiej IDE layer
at the moment but that won't matter to most users.

The patch does the following
- Add IT8211/12 to pci_ids.h
- Add Makefile/Kconfig entry
- Add it8212 driver

No core IDE code is touched by this diff

Embedded system testing and the ability to force raid mode off by David
Howells

Made possible by the ite reference code, documentation and also several
clarifications and pieces of assistance provided by ITE themselves

Signed-off-by: Alan Cox <alan@redhat.com>
Acked-by: Bartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 812 insertions, 0 deletions

diff --git a/drivers/ide/pci/it821x.c b/drivers/ide/pci/it821x.c
new file mode 100644
index 000000000000..e440036e651f
--- /dev/null
+++ b/drivers/ide/pci/it821x.c
@@ -0,0 +1,812 @@
+
+/*
+ * linux/drivers/ide/pci/it821x.c               Version 0.09    December 2004
+ *
+ * Copyright (C) 2004           Red Hat <alan@redhat.com>
+ *
+ *  May be copied or modified under the terms of the GNU General Public License
+ *  Based in part on the ITE vendor provided SCSI driver.
+ *
+ *  Documentation available from
+ *      http://www.ite.com.tw/pc/IT8212F_V04.pdf
+ *  Some other documents are NDA.
+ *
+ *  The ITE8212 isn't exactly a standard IDE controller. It has two
+ *  modes. In pass through mode then it is an IDE controller. In its smart
+ *  mode its actually quite a capable hardware raid controller disguised
+ *  as an IDE controller. Smart mode only understands DMA read/write and
+ *  identify, none of the fancier commands apply. The IT8211 is identical
+ *  in other respects but lacks the raid mode.
+ *
+ *  Errata:
+ *  o   Rev 0x10 also requires master/slave hold the same DMA timings and
+ *      cannot do ATAPI MWDMA.
+ *  o   The identify data for raid volumes lacks CHS info (technically ok)
+ *      but also fails to set the LBA28 and other bits. We fix these in
+ *      the IDE probe quirk code.
+ *  o   If you write LBA48 sized I/O's (ie > 256 sector) in smart mode
+ *      raid then the controller firmware dies
+ *  o   Smart mode without RAID doesn't clear all the necessary identify
+ *      bits to reduce the command set to the one used
+ *
+ *  This has a few impacts on the driver
+ *  - In pass through mode we do all the work you would expect
+ *  - In smart mode the clocking set up is done by the controller generally
+ *    but we must watch the other limits and filter.
+ *  - There are a few extra vendor commands that actually talk to the
+ *    controller but only work PIO with no IRQ.
+ *
+ *  Vendor areas of the identify block in smart mode are used for the
+ *  timing and policy set up. Each HDD in raid mode also has a serial
+ *  block on the disk. The hardware extra commands are get/set chip status,
+ *  rebuild, get rebuild status.
+ *
+ *  In Linux the driver supports pass through mode as if the device was
+ *  just another IDE controller. If the smart mode is running then
+ *  volumes are managed by the controller firmware and each IDE "disk"
+ *  is a raid volume. Even more cute - the controller can do automated
+ *  hotplug and rebuild.
+ *
+ *  The pass through controller itself is a little demented. It has a
+ *  flaw that it has a single set of PIO/MWDMA timings per channel so
+ *  non UDMA devices restrict each others performance. It also has a
+ *  single clock source per channel so mixed UDMA100/133 performance
+ *  isn't perfect and we have to pick a clock. Thankfully none of this
+ *  matters in smart mode. ATAPI DMA is not currently supported.
+ *
+ *  It seems the smart mode is a win for RAID1/RAID10 but otherwise not.
+ *
+ *  TODO
+ *      -       ATAPI UDMA is ok but not MWDMA it seems
+ *      -       RAID configuration ioctls
+ *      -       Move to libata once it grows up
+ */
+
+#include <linux/config.h>
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <linux/hdreg.h>
+#include <linux/ide.h>
+#include <linux/init.h>
+
+#include <asm/io.h>
+
+struct it821x_dev
+{
+        unsigned int smart:1,           /* Are we in smart raid mode */
+                timing10:1;             /* Rev 0x10 */
+        u8      clock_mode;             /* 0, ATA_50 or ATA_66 */
+        u8      want[2][2];             /* Mode/Pri log for master slave */
+        /* We need these for switching the clock when DMA goes on/off
+           The high byte is the 66Mhz timing */
+        u16     pio[2];                 /* Cached PIO values */
+        u16     mwdma[2];               /* Cached MWDMA values */
+        u16     udma[2];                /* Cached UDMA values (per drive) */
+};
+
+#define ATA_66          0
+#define ATA_50          1
+#define ATA_ANY         2
+
+#define UDMA_OFF        0
+#define MWDMA_OFF       0
+
+/*
+ *      We allow users to force the card into non raid mode without
+ *      flashing the alternative BIOS. This is also neccessary right now
+ *      for embedded platforms that cannot run a PC BIOS but are using this
+ *      device.
+ */
+
+static int it8212_noraid;
+
+/**
+ *      it821x_program  -       program the PIO/MWDMA registers
+ *      @drive: drive to tune
+ *
+ *      Program the PIO/MWDMA timing for this channel according to the
+ *      current clock.
+ */
+
+static void it821x_program(ide_drive_t *drive, u16 timing)
+{
+        ide_hwif_t *hwif        = drive->hwif;
+        struct it821x_dev *itdev = ide_get_hwifdata(hwif);
+        int channel = hwif->channel;
+        u8 conf;
+
+        /* Program PIO/MWDMA timing bits */
+        if(itdev->clock_mode == ATA_66)
+                conf = timing >> 8;
+        else
+                conf = timing & 0xFF;
+        pci_write_config_byte(hwif->pci_dev, 0x54 + 4 * channel, conf);
+}
+
+/**
+ *      it821x_program_udma     -       program the UDMA registers
+ *      @drive: drive to tune
+ *
+ *      Program the UDMA timing for this drive according to the
+ *      current clock.
+ */
+
+static void it821x_program_udma(ide_drive_t *drive, u16 timing)
+{
+        ide_hwif_t *hwif        = drive->hwif;
+        struct it821x_dev *itdev = ide_get_hwifdata(hwif);
+        int channel = hwif->channel;
+        int unit = drive->select.b.unit;
+        u8 conf;
+
+        /* Program UDMA timing bits */
+        if(itdev->clock_mode == ATA_66)
+                conf = timing >> 8;
+        else
+                conf = timing & 0xFF;
+        if(itdev->timing10 == 0)
+                pci_write_config_byte(hwif->pci_dev, 0x56 + 4 * channel + unit, conf);
+        else {
+                pci_write_config_byte(hwif->pci_dev, 0x56 + 4 * channel, conf);
+                pci_write_config_byte(hwif->pci_dev, 0x56 + 4 * channel + 1, conf);
+        }
+}
+
+
+/**
+ *      it821x_clock_strategy
+ *      @hwif: hardware interface
+ *
+ *      Select between the 50 and 66Mhz base clocks to get the best
+ *      results for this interface.
+ */
+
+static void it821x_clock_strategy(ide_drive_t *drive)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        struct it821x_dev *itdev = ide_get_hwifdata(hwif);
+
+        u8 unit = drive->select.b.unit;
+        ide_drive_t *pair = &hwif->drives[1-unit];
+
+        int clock, altclock;
+        u8 v;
+        int sel = 0;
+
+        if(itdev->want[0][0] > itdev->want[1][0]) {
+                clock = itdev->want[0][1];
+                altclock = itdev->want[1][1];
+        } else {
+                clock = itdev->want[1][1];
+                altclock = itdev->want[0][1];
+        }
+
+        /* Master doesn't care does the slave ? */
+        if(clock == ATA_ANY)
+                clock = altclock;
+
+        /* Nobody cares - keep the same clock */
+        if(clock == ATA_ANY)
+                return;
+        /* No change */
+        if(clock == itdev->clock_mode)
+                return;
+
+        /* Load this into the controller ? */
+        if(clock == ATA_66)
+                itdev->clock_mode = ATA_66;
+        else {
+                itdev->clock_mode = ATA_50;
+                sel = 1;
+        }
+        pci_read_config_byte(hwif->pci_dev, 0x50, &v);
+        v &= ~(1 << (1 + hwif->channel));
+        v |= sel << (1 + hwif->channel);
+        pci_write_config_byte(hwif->pci_dev, 0x50, v);
+
+        /*
+         *      Reprogram the UDMA/PIO of the pair drive for the switch
+         *      MWDMA will be dealt with by the dma switcher
+         */
+        if(pair && itdev->udma[1-unit] != UDMA_OFF) {
+                it821x_program_udma(pair, itdev->udma[1-unit]);
+                it821x_program(pair, itdev->pio[1-unit]);
+        }
+        /*
+         *      Reprogram the UDMA/PIO of our drive for the switch.
+         *      MWDMA will be dealt with by the dma switcher
+         */
+        if(itdev->udma[unit] != UDMA_OFF) {
+                it821x_program_udma(drive, itdev->udma[unit]);
+                it821x_program(drive, itdev->pio[unit]);
+        }
+}
+
+/**
+ *      it821x_ratemask -       Compute available modes
+ *      @drive: IDE drive
+ *
+ *      Compute the available speeds for the devices on the interface. This
+ *      is all modes to ATA133 clipped by drive cable setup.
+ */
+
+static u8 it821x_ratemask (ide_drive_t *drive)
+{
+        u8 mode = 4;
+        if (!eighty_ninty_three(drive))
+                mode = min(mode, (u8)1);
+        return mode;
+}
+
+/**
+ *      it821x_tuneproc -       tune a drive
+ *      @drive: drive to tune
+ *      @mode_wanted: the target operating mode
+ *
+ *      Load the timing settings for this device mode into the
+ *      controller. By the time we are called the mode has been
+ *      modified as neccessary to handle the absence of seperate
+ *      master/slave timers for MWDMA/PIO.
+ *
+ *      This code is only used in pass through mode.
+ */
+
+static void it821x_tuneproc (ide_drive_t *drive, byte mode_wanted)
+{
+        ide_hwif_t *hwif        = drive->hwif;
+        struct it821x_dev *itdev = ide_get_hwifdata(hwif);
+        int unit = drive->select.b.unit;
+
+        /* Spec says 89 ref driver uses 88 */
+        static u16 pio[]        = { 0xAA88, 0xA382, 0xA181, 0x3332, 0x3121 };
+        static u8 pio_want[]    = { ATA_66, ATA_66, ATA_66, ATA_66, ATA_ANY };
+
+        if(itdev->smart)
+                return;
+
+        /* We prefer 66Mhz clock for PIO 0-3, don't care for PIO4 */
+        itdev->want[unit][1] = pio_want[mode_wanted];
+        itdev->want[unit][0] = 1;       /* PIO is lowest priority */
+        itdev->pio[unit] = pio[mode_wanted];
+        it821x_clock_strategy(drive);
+        it821x_program(drive, itdev->pio[unit]);
+}
+
+/**
+ *      it821x_tune_mwdma       -       tune a channel for MWDMA
+ *      @drive: drive to set up
+ *      @mode_wanted: the target operating mode
+ *
+ *      Load the timing settings for this device mode into the
+ *      controller when doing MWDMA in pass through mode. The caller
+ *      must manage the whole lack of per device MWDMA/PIO timings and
+ *      the shared MWDMA/PIO timing register.
+ */
+
+static void it821x_tune_mwdma (ide_drive_t *drive, byte mode_wanted)
+{
+        ide_hwif_t *hwif        = drive->hwif;
+        struct it821x_dev *itdev = (void *)ide_get_hwifdata(hwif);
+        int unit = drive->select.b.unit;
+        int channel = hwif->channel;
+        u8 conf;
+
+        static u16 dma[]        = { 0x8866, 0x3222, 0x3121 };
+        static u8 mwdma_want[]  = { ATA_ANY, ATA_66, ATA_ANY };
+
+        itdev->want[unit][1] = mwdma_want[mode_wanted];
+        itdev->want[unit][0] = 2;       /* MWDMA is low priority */
+        itdev->mwdma[unit] = dma[mode_wanted];
+        itdev->udma[unit] = UDMA_OFF;
+
+        /* UDMA bits off - Revision 0x10 do them in pairs */
+        pci_read_config_byte(hwif->pci_dev, 0x50, &conf);
+        if(itdev->timing10)
+                conf |= channel ? 0x60: 0x18;
+        else
+                conf |= 1 << (3 + 2 * channel + unit);
+        pci_write_config_byte(hwif->pci_dev, 0x50, conf);
+
+        it821x_clock_strategy(drive);
+        /* FIXME: do we need to program this ? */
+        /* it821x_program(drive, itdev->mwdma[unit]); */
+}
+
+/**
+ *      it821x_tune_udma        -       tune a channel for UDMA
+ *      @drive: drive to set up
+ *      @mode_wanted: the target operating mode
+ *
+ *      Load the timing settings for this device mode into the
+ *      controller when doing UDMA modes in pass through.
+ */
+
+static void it821x_tune_udma (ide_drive_t *drive, byte mode_wanted)
+{
+        ide_hwif_t *hwif        = drive->hwif;
+        struct it821x_dev *itdev = ide_get_hwifdata(hwif);
+        int unit = drive->select.b.unit;
+        int channel = hwif->channel;
+        u8 conf;
+
+        static u16 udma[]       = { 0x4433, 0x4231, 0x3121, 0x2121, 0x1111, 0x2211, 0x1111 };
+        static u8 udma_want[]   = { ATA_ANY, ATA_50, ATA_ANY, ATA_66, ATA_66, ATA_50, ATA_66 };
+
+        itdev->want[unit][1] = udma_want[mode_wanted];
+        itdev->want[unit][0] = 3;       /* UDMA is high priority */
+        itdev->mwdma[unit] = MWDMA_OFF;
+        itdev->udma[unit] = udma[mode_wanted];
+        if(mode_wanted >= 5)
+                itdev->udma[unit] |= 0x8080;    /* UDMA 5/6 select on */
+
+        /* UDMA on. Again revision 0x10 must do the pair */
+        pci_read_config_byte(hwif->pci_dev, 0x50, &conf);
+        if(itdev->timing10)
+                conf &= channel ? 0x9F: 0xE7;
+        else
+                conf &= ~ (1 << (3 + 2 * channel + unit));
+        pci_write_config_byte(hwif->pci_dev, 0x50, conf);
+
+        it821x_clock_strategy(drive);
+        it821x_program_udma(drive, itdev->udma[unit]);
+
+}
+
+/**
+ *      config_it821x_chipset_for_pio   -       set drive timings
+ *      @drive: drive to tune
+ *      @speed we want
+ *
+ *      Compute the best pio mode we can for a given device. We must
+ *      pick a speed that does not cause problems with the other device
+ *      on the cable.
+ */
+
+static void config_it821x_chipset_for_pio (ide_drive_t *drive, byte set_speed)
+{
+        u8 unit = drive->select.b.unit;
+        ide_hwif_t *hwif = drive->hwif;
+        ide_drive_t *pair = &hwif->drives[1-unit];
+        u8 speed = 0, set_pio   = ide_get_best_pio_mode(drive, 255, 5, NULL);
+        u8 pair_pio;
+
+        /* We have to deal with this mess in pairs */
+        if(pair != NULL) {
+                pair_pio = ide_get_best_pio_mode(pair, 255, 5, NULL);
+                /* Trim PIO to the slowest of the master/slave */
+                if(pair_pio < set_pio)
+                        set_pio = pair_pio;
+        }
+        it821x_tuneproc(drive, set_pio);
+        speed = XFER_PIO_0 + set_pio;
+        /* XXX - We trim to the lowest of the pair so the other drive
+           will always be fine at this point until we do hotplug passthru */
+
+        if (set_speed)
+                (void) ide_config_drive_speed(drive, speed);
+}
+
+/**
+ *      it821x_dma_read -       DMA hook
+ *      @drive: drive for DMA
+ *
+ *      The IT821x has a single timing register for MWDMA and for PIO
+ *      operations. As we flip back and forth we have to reload the
+ *      clock. In addition the rev 0x10 device only works if the same
+ *      timing value is loaded into the master and slave UDMA clock
+ *      so we must also reload that.
+ *
+ *      FIXME: we could figure out in advance if we need to do reloads
+ */
+
+static void it821x_dma_start(ide_drive_t *drive)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        struct it821x_dev *itdev = ide_get_hwifdata(hwif);
+        int unit = drive->select.b.unit;
+        if(itdev->mwdma[unit] != MWDMA_OFF)
+                it821x_program(drive, itdev->mwdma[unit]);
+        else if(itdev->udma[unit] != UDMA_OFF && itdev->timing10)
+                it821x_program_udma(drive, itdev->udma[unit]);
+        ide_dma_start(drive);
+}
+
+/**
+ *      it821x_dma_write        -       DMA hook
+ *      @drive: drive for DMA stop
+ *
+ *      The IT821x has a single timing register for MWDMA and for PIO
+ *      operations. As we flip back and forth we have to reload the
+ *      clock.
+ */
+
+static int it821x_dma_end(ide_drive_t *drive)
+{
+        ide_hwif_t *hwif = drive->hwif;
+        int unit = drive->select.b.unit;
+        struct it821x_dev *itdev = ide_get_hwifdata(hwif);
+        int ret = __ide_dma_end(drive);
+        if(itdev->mwdma[unit] != MWDMA_OFF)
+                it821x_program(drive, itdev->pio[unit]);
+        return ret;
+}
+
+
+/**
+ *      it821x_tune_chipset     -       set controller timings
+ *      @drive: Drive to set up
+ *      @xferspeed: speed we want to achieve
+ *
+ *      Tune the ITE chipset for the desired mode. If we can't achieve
+ *      the desired mode then tune for a lower one, but ultimately
+ *      make the thing work.
+ */
+
+static int it821x_tune_chipset (ide_drive_t *drive, byte xferspeed)
+{
+
+        ide_hwif_t *hwif        = drive->hwif;
+        struct it821x_dev *itdev = ide_get_hwifdata(hwif);
+        u8 speed                = ide_rate_filter(it821x_ratemask(drive), xferspeed);
+
+        if(!itdev->smart) {
+                switch(speed) {
+                        case XFER_PIO_4:
+                        case XFER_PIO_3:
+                        case XFER_PIO_2:
+                        case XFER_PIO_1:
+                        case XFER_PIO_0:
+                                it821x_tuneproc(drive, (speed - XFER_PIO_0));
+                                break;
+                        /* MWDMA tuning is really hard because our MWDMA and PIO
+                           timings are kept in the same place. We can switch in the
+                           host dma on/off callbacks */
+                        case XFER_MW_DMA_2:
+                        case XFER_MW_DMA_1:
+                        case XFER_MW_DMA_0:
+                                it821x_tune_mwdma(drive, (speed - XFER_MW_DMA_0));
+                                break;
+                        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:
+                                it821x_tune_udma(drive, (speed - XFER_UDMA_0));
+                                break;
+                        default:
+                                return 1;
+                }
+        }
+        /*
+         *      In smart mode the clocking is done by the host controller
+         *      snooping the mode we picked. The rest of it is not our problem
+         */
+        return ide_config_drive_speed(drive, speed);
+}
+
+/**
+ *      config_chipset_for_dma  -       configure for DMA
+ *      @drive: drive to configure
+ *
+ *      Called by the IDE layer when it wants the timings set up.
+ */
+
+static int config_chipset_for_dma (ide_drive_t *drive)
+{
+        u8 speed        = ide_dma_speed(drive, it821x_ratemask(drive));
+
+        config_it821x_chipset_for_pio(drive, !speed);
+        it821x_tune_chipset(drive, speed);
+        return ide_dma_enable(drive);
+}
+
+/**
+ *      it821x_configure_drive_for_dma  -       set up for DMA transfers
+ *      @drive: drive we are going to set up
+ *
+ *      Set up the drive for DMA, tune the controller and drive as
+ *      required. If the drive isn't suitable for DMA or we hit
+ *      other problems then we will drop down to PIO and set up
+ *      PIO appropriately
+ */
+
+static int it821x_config_drive_for_dma (ide_drive_t *drive)
+{
+        ide_hwif_t *hwif        = drive->hwif;
+
+        if (ide_use_dma(drive)) {
+                if (config_chipset_for_dma(drive))
+                        return hwif->ide_dma_on(drive);
+        }
+        config_it821x_chipset_for_pio(drive, 1);
+        return hwif->ide_dma_off_quietly(drive);
+}
+
+/**
+ *      ata66_it821x    -       check for 80 pin cable
+ *      @hwif: interface to check
+ *
+ *      Check for the presence of an ATA66 capable cable on the
+ *      interface. Problematic as it seems some cards don't have
+ *      the needed logic onboard.
+ */
+
+static unsigned int __devinit ata66_it821x(ide_hwif_t *hwif)
+{
+        /* The reference driver also only does disk side */
+        return 1;
+}
+
+/**
+ *      it821x_fixup    -       post init callback
+ *      @hwif: interface
+ *
+ *      This callback is run after the drives have been probed but
+ *      before anything gets attached. It allows drivers to do any
+ *      final tuning that is needed, or fixups to work around bugs.
+ */
+
+static void __devinit it821x_fixups(ide_hwif_t *hwif)
+{
+        struct it821x_dev *itdev = ide_get_hwifdata(hwif);
+        int i;
+
+        if(!itdev->smart) {
+                /*
+                 *      If we are in pass through mode then not much
+                 *      needs to be done, but we do bother to clear the
+                 *      IRQ mask as we may well be in PIO (eg rev 0x10)
+                 *      for now and we know unmasking is safe on this chipset.
+                 */
+                for (i = 0; i < 2; i++) {
+                        ide_drive_t *drive = &hwif->drives[i];
+                        if(drive->present)
+                                drive->unmask = 1;
+                }
+                return;
+        }
+        /*
+         *      Perform fixups on smart mode. We need to "lose" some
+         *      capabilities the firmware lacks but does not filter, and
+         *      also patch up some capability bits that it forgets to set
+         *      in RAID mode.
+         */
+
+        for(i = 0; i < 2; i++) {
+                ide_drive_t *drive = &hwif->drives[i];
+                struct hd_driveid *id;
+                u16 *idbits;
+
+                if(!drive->present)
+                        continue;
+                id = drive->id;
+                idbits = (u16 *)drive->id;
+
+                /* Check for RAID v native */
+                if(strstr(id->model, "Integrated Technology Express")) {
+                        /* In raid mode the ident block is slightly buggy
+                           We need to set the bits so that the IDE layer knows
+                           LBA28. LBA48 and DMA ar valid */
+                        id->capability |= 3;            /* LBA28, DMA */
+                        id->command_set_2 |= 0x0400;    /* LBA48 valid */
+                        id->cfs_enable_2 |= 0x0400;     /* LBA48 on */
+                        /* Reporting logic */
+                        printk(KERN_INFO "%s: IT8212 %sRAID %d volume",
+                                drive->name,
+                                idbits[147] ? "Bootable ":"",
+                                idbits[129]);
+                                if(idbits[129] != 1)
+                                        printk("(%dK stripe)", idbits[146]);
+                                printk(".\n");
+                        /* Now the core code will have wrongly decided no DMA
+                           so we need to fix this */
+                        hwif->ide_dma_off_quietly(drive);
+#ifdef CONFIG_IDEDMA_ONLYDISK
+                        if (drive->media == ide_disk)
+#endif
+                                hwif->ide_dma_check(drive);
+                } else {
+                        /* Non RAID volume. Fixups to stop the core code
+                           doing unsupported things */
+                        id->field_valid &= 1;
+                        id->queue_depth = 0;
+                        id->command_set_1 = 0;
+                        id->command_set_2 &= 0xC400;
+                        id->cfsse &= 0xC000;
+                        id->cfs_enable_1 = 0;
+                        id->cfs_enable_2 &= 0xC400;
+                        id->csf_default &= 0xC000;
+                        id->word127 = 0;
+                        id->dlf = 0;
+                        id->csfo = 0;
+                        id->cfa_power = 0;
+                        printk(KERN_INFO "%s: Performing identify fixups.\n",
+                                drive->name);
+                }
+        }
+
+}
+
+/**
+ *      init_hwif_it821x        -       set up hwif structs
+ *      @hwif: interface to set up
+ *
+ *      We do the basic set up of the interface structure. The IT8212
+ *      requires several custom handlers so we override the default
+ *      ide DMA handlers appropriately
+ */
+
+static void __devinit init_hwif_it821x(ide_hwif_t *hwif)
+{
+        struct it821x_dev *idev = kmalloc(sizeof(struct it821x_dev), GFP_KERNEL);
+        u8 conf;
+
+        if(idev == NULL) {
+                printk(KERN_ERR "it821x: out of memory, falling back to legacy behaviour.\n");
+                goto fallback;
+        }
+        memset(idev, 0, sizeof(struct it821x_dev));
+        ide_set_hwifdata(hwif, idev);
+
+        pci_read_config_byte(hwif->pci_dev, 0x50, &conf);
+        if(conf & 1) {
+                idev->smart = 1;
+                hwif->atapi_dma = 0;
+                /* Long I/O's although allowed in LBA48 space cause the
+                   onboard firmware to enter the twighlight zone */
+                hwif->rqsize = 256;
+        }
+
+        /* Pull the current clocks from 0x50 also */
+        if (conf & (1 << (1 + hwif->channel)))
+                idev->clock_mode = ATA_50;
+        else
+                idev->clock_mode = ATA_66;
+
+        idev->want[0][1] = ATA_ANY;
+        idev->want[1][1] = ATA_ANY;
+
+        /*
+         *      Not in the docs but according to the reference driver
+         *      this is neccessary.
+         */
+
+        pci_read_config_byte(hwif->pci_dev, 0x08, &conf);
+        if(conf == 0x10) {
+                idev->timing10 = 1;
+                hwif->atapi_dma = 0;
+                if(!idev->smart)
+                        printk(KERN_WARNING "it821x: Revision 0x10, workarounds activated.\n");
+        }
+
+        hwif->speedproc = &it821x_tune_chipset;
+        hwif->tuneproc  = &it821x_tuneproc;
+
+        /* MWDMA/PIO clock switching for pass through mode */
+        if(!idev->smart) {
+                hwif->dma_start = &it821x_dma_start;
+                hwif->ide_dma_end = &it821x_dma_end;
+        }
+
+        hwif->drives[0].autotune = 1;
+        hwif->drives[1].autotune = 1;
+
+        if (!hwif->dma_base)
+                goto fallback;
+
+        hwif->ultra_mask = 0x7f;
+        hwif->mwdma_mask = 0x07;
+        hwif->swdma_mask = 0x07;
+
+        hwif->ide_dma_check = &it821x_config_drive_for_dma;
+        if (!(hwif->udma_four))
+                hwif->udma_four = ata66_it821x(hwif);
+
+        /*
+         *      The BIOS often doesn't set up DMA on this controller
+         *      so we always do it.
+         */
+
+        hwif->autodma = 1;
+        hwif->drives[0].autodma = hwif->autodma;
+        hwif->drives[1].autodma = hwif->autodma;
+        return;
+fallback:
+        hwif->autodma = 0;
+        return;
+}
+
+static void __devinit it8212_disable_raid(struct pci_dev *dev)
+{
+        /* Reset local CPU, and set BIOS not ready */
+        pci_write_config_byte(dev, 0x5E, 0x01);
+
+        /* Set to bypass mode, and reset PCI bus */
+        pci_write_config_byte(dev, 0x50, 0x00);
+        pci_write_config_word(dev, PCI_COMMAND,
+                              PCI_COMMAND_PARITY | PCI_COMMAND_IO |
+                              PCI_COMMAND_MEMORY | PCI_COMMAND_MASTER);
+        pci_write_config_word(dev, 0x40, 0xA0F3);
+
+        pci_write_config_dword(dev,0x4C, 0x02040204);
+        pci_write_config_byte(dev, 0x42, 0x36);
+        pci_write_config_byte(dev, PCI_LATENCY_TIMER, 0);
+}
+
+static unsigned int __devinit init_chipset_it821x(struct pci_dev *dev, const char *name)
+{
+        u8 conf;
+        static char *mode[2] = { "pass through", "smart" };
+
+        /* Force the card into bypass mode if so requested */
+        if (it8212_noraid) {
+                printk(KERN_INFO "it8212: forcing bypass mode.\n");
+                it8212_disable_raid(dev);
+        }
+        pci_read_config_byte(dev, 0x50, &conf);
+        printk(KERN_INFO "it821x: controller in %s mode.\n", mode[conf & 1]);
+        return 0;
+}
+
+
+#define DECLARE_ITE_DEV(name_str)                       \
+        {                                               \
+                .name           = name_str,             \
+                .init_chipset   = init_chipset_it821x,  \
+                .init_hwif      = init_hwif_it821x,     \
+                .channels       = 2,                    \
+                .autodma        = AUTODMA,              \
+                .bootable       = ON_BOARD,             \
+                .fixup          = it821x_fixups         \
+        }
+
+static ide_pci_device_t it821x_chipsets[] __devinitdata = {
+        /* 0 */ DECLARE_ITE_DEV("IT8212"),
+};
+
+/**
+ *      it821x_init_one -       pci layer discovery entry
+ *      @dev: PCI device
+ *      @id: ident table entry
+ *
+ *      Called by the PCI code when it finds an ITE821x controller.
+ *      We then use the IDE PCI generic helper to do most of the work.
+ */
+
+static int __devinit it821x_init_one(struct pci_dev *dev, const struct pci_device_id *id)
+{
+        ide_setup_pci_device(dev, &it821x_chipsets[id->driver_data]);
+        return 0;
+}
+
+static struct pci_device_id it821x_pci_tbl[] = {
+        { PCI_VENDOR_ID_ITE, PCI_DEVICE_ID_ITE_8211,  PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
+        { PCI_VENDOR_ID_ITE, PCI_DEVICE_ID_ITE_8212,  PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0},
+        { 0, },
+};
+
+MODULE_DEVICE_TABLE(pci, it821x_pci_tbl);
+
+static struct pci_driver driver = {
+        .name           = "ITE821x IDE",
+        .id_table       = it821x_pci_tbl,
+        .probe          = it821x_init_one,
+};
+
+static int __init it821x_ide_init(void)
+{
+        return ide_pci_register_driver(&driver);
+}
+
+module_init(it821x_ide_init);
+
+module_param_named(noraid, it8212_noraid, int, S_IRUGO);
+MODULE_PARM_DESC(it8212_noraid, "Force card into bypass mode");
+
+MODULE_AUTHOR("Alan Cox");
+MODULE_DESCRIPTION("PCI driver module for the ITE 821x");
+MODULE_LICENSE("GPL");