x86: block irq balancing for timer

[linux-2.6/linux-acpi-2.6/ibm-acpi-2.6.git] / drivers / ata / pata_legacy.c

/*
 *   pata-legacy.c - Legacy port PATA/SATA controller driver.
 *   Copyright 2005/2006 Red Hat <alan@redhat.com>, all rights reserved.
 *
 *  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, or (at your option)
 *  any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *   An ATA driver for the legacy ATA ports.
 *
 *   Data Sources:
 *      Opti 82C465/82C611 support: Data sheets at opti-inc.com
 *      HT6560 series:
 *      Promise 20230/20620:
 *              http://www.ryston.cz/petr/vlb/pdc20230b.html
 *              http://www.ryston.cz/petr/vlb/pdc20230c.html
 *              http://www.ryston.cz/petr/vlb/pdc20630.html
 *
 *  Unsupported but docs exist:
 *      Appian/Adaptec AIC25VL01/Cirrus Logic PD7220
 *      Winbond W83759A
 *
 *  This driver handles legacy (that is "ISA/VLB side") IDE ports found
 *  on PC class systems. There are three hybrid devices that are exceptions
 *  The Cyrix 5510/5520 where a pre SFF ATA device is on the bridge and
 *  the MPIIX where the tuning is PCI side but the IDE is "ISA side".
 *
 *  Specific support is included for the ht6560a/ht6560b/opti82c611a/
 *  opti82c465mv/promise 20230c/20630
 *
 *  Use the autospeed and pio_mask options with:
 *      Appian ADI/2 aka CLPD7220 or AIC25VL01.
 *  Use the jumpers, autospeed and set pio_mask to the mode on the jumpers with
 *      Goldstar GM82C711, PIC-1288A-125, UMC 82C871F, Winbond W83759,
 *      Winbond W83759A, Promise PDC20230-B
 *
 *  For now use autospeed and pio_mask as above with the W83759A. This may
 *  change.
 *
 *  TODO
 *      Merge existing pata_qdi driver
 *
 */

#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/init.h>
#include <linux/blkdev.h>
#include <linux/delay.h>
#include <scsi/scsi_host.h>
#include <linux/ata.h>
#include <linux/libata.h>
#include <linux/platform_device.h>

#define DRV_NAME "pata_legacy"
#define DRV_VERSION "0.5.5"

#define NR_HOST 6

static int legacy_port[NR_HOST] = { 0x1f0, 0x170, 0x1e8, 0x168, 0x1e0, 0x160 };
static int legacy_irq[NR_HOST] = { 14, 15, 11, 10, 8, 12 };

struct legacy_data {
        unsigned long timing;
        u8 clock[2];
        u8 last;
        int fast;
        struct platform_device *platform_dev;

};

static struct legacy_data legacy_data[NR_HOST];
static struct ata_host *legacy_host[NR_HOST];
static int nr_legacy_host;


static int probe_all;                   /* Set to check all ISA port ranges */
static int ht6560a;                     /* HT 6560A on primary 1, secondary 2, both 3 */
static int ht6560b;                     /* HT 6560A on primary 1, secondary 2, both 3 */
static int opti82c611a;                 /* Opti82c611A on primary 1, secondary 2, both 3 */
static int opti82c46x;                  /* Opti 82c465MV present (pri/sec autodetect) */
static int autospeed;                   /* Chip present which snoops speed changes */
static int pio_mask = 0x1F;             /* PIO range for autospeed devices */
static int iordy_mask = 0xFFFFFFFF;     /* Use iordy if available */

/**
 *      legacy_set_mode         -       mode setting
 *      @ap: IDE interface
 *      @unused: Device that failed when error is returned
 *
 *      Use a non standard set_mode function. We don't want to be tuned.
 *
 *      The BIOS configured everything. Our job is not to fiddle. Just use
 *      whatever PIO the hardware is using and leave it at that. When we
 *      get some kind of nice user driven API for control then we can
 *      expand on this as per hdparm in the base kernel.
 */

static int legacy_set_mode(struct ata_port *ap, struct ata_device **unused)
{
        int i;

        for (i = 0; i < ATA_MAX_DEVICES; i++) {
                struct ata_device *dev = &ap->device[i];
                if (ata_dev_enabled(dev)) {
                        ata_dev_printk(dev, KERN_INFO, "configured for PIO\n");
                        dev->pio_mode = XFER_PIO_0;
                        dev->xfer_mode = XFER_PIO_0;
                        dev->xfer_shift = ATA_SHIFT_PIO;
                        dev->flags |= ATA_DFLAG_PIO;
                }
        }
        return 0;
}

static struct scsi_host_template legacy_sht = {
        .module                 = THIS_MODULE,
        .name                   = DRV_NAME,
        .ioctl                  = ata_scsi_ioctl,
        .queuecommand           = ata_scsi_queuecmd,
        .can_queue              = ATA_DEF_QUEUE,
        .this_id                = ATA_SHT_THIS_ID,
        .sg_tablesize           = LIBATA_MAX_PRD,
        .cmd_per_lun            = ATA_SHT_CMD_PER_LUN,
        .emulated               = ATA_SHT_EMULATED,
        .use_clustering         = ATA_SHT_USE_CLUSTERING,
        .proc_name              = DRV_NAME,
        .dma_boundary           = ATA_DMA_BOUNDARY,
        .slave_configure        = ata_scsi_slave_config,
        .slave_destroy          = ata_scsi_slave_destroy,
        .bios_param             = ata_std_bios_param,
};

/*
 *      These ops are used if the user indicates the hardware
 *      snoops the commands to decide on the mode and handles the
 *      mode selection "magically" itself. Several legacy controllers
 *      do this. The mode range can be set if it is not 0x1F by setting
 *      pio_mask as well.
 */

static struct ata_port_operations simple_port_ops = {
        .port_disable   = ata_port_disable,
        .tf_load        = ata_tf_load,
        .tf_read        = ata_tf_read,
        .check_status   = ata_check_status,
        .exec_command   = ata_exec_command,
        .dev_select     = ata_std_dev_select,

        .freeze         = ata_bmdma_freeze,
        .thaw           = ata_bmdma_thaw,
        .error_handler  = ata_bmdma_error_handler,
        .post_internal_cmd = ata_bmdma_post_internal_cmd,
        .cable_detect   = ata_cable_40wire,

        .qc_prep        = ata_qc_prep,
        .qc_issue       = ata_qc_issue_prot,

        .data_xfer      = ata_data_xfer_noirq,

        .irq_handler    = ata_interrupt,
        .irq_clear      = ata_bmdma_irq_clear,
        .irq_on         = ata_irq_on,
        .irq_ack        = ata_irq_ack,

        .port_start     = ata_port_start,
};

static struct ata_port_operations legacy_port_ops = {
        .set_mode       = legacy_set_mode,

        .port_disable   = ata_port_disable,
        .tf_load        = ata_tf_load,
        .tf_read        = ata_tf_read,
        .check_status   = ata_check_status,
        .exec_command   = ata_exec_command,
        .dev_select     = ata_std_dev_select,
        .cable_detect   = ata_cable_40wire,

        .freeze         = ata_bmdma_freeze,
        .thaw           = ata_bmdma_thaw,
        .error_handler  = ata_bmdma_error_handler,
        .post_internal_cmd = ata_bmdma_post_internal_cmd,

        .qc_prep        = ata_qc_prep,
        .qc_issue       = ata_qc_issue_prot,

        .data_xfer      = ata_data_xfer_noirq,

        .irq_handler    = ata_interrupt,
        .irq_clear      = ata_bmdma_irq_clear,
        .irq_on         = ata_irq_on,
        .irq_ack        = ata_irq_ack,

        .port_start     = ata_port_start,
};

/*
 *      Promise 20230C and 20620 support
 *
 *      This controller supports PIO0 to PIO2. We set PIO timings conservatively to
 *      allow for 50MHz Vesa Local Bus. The 20620 DMA support is weird being DMA to
 *      controller and PIO'd to the host and not supported.
 */

static void pdc20230_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
        int tries = 5;
        int pio = adev->pio_mode - XFER_PIO_0;
        u8 rt;
        unsigned long flags;

        /* Safe as UP only. Force I/Os to occur together */

        local_irq_save(flags);

        /* Unlock the control interface */
        do
        {
                inb(0x1F5);
                outb(inb(0x1F2) | 0x80, 0x1F2);
                inb(0x1F2);
                inb(0x3F6);
                inb(0x3F6);
                inb(0x1F2);
                inb(0x1F2);
        }
        while((inb(0x1F2) & 0x80) && --tries);

        local_irq_restore(flags);

        outb(inb(0x1F4) & 0x07, 0x1F4);

        rt = inb(0x1F3);
        rt &= 0x07 << (3 * adev->devno);
        if (pio)
                rt |= (1 + 3 * pio) << (3 * adev->devno);

        udelay(100);
        outb(inb(0x1F2) | 0x01, 0x1F2);
        udelay(100);
        inb(0x1F5);

}

static void pdc_data_xfer_vlb(struct ata_device *adev, unsigned char *buf, unsigned int buflen, int write_data)
{
        struct ata_port *ap = adev->ap;
        int slop = buflen & 3;
        unsigned long flags;

        if (ata_id_has_dword_io(adev->id)) {
                local_irq_save(flags);

                /* Perform the 32bit I/O synchronization sequence */
                ioread8(ap->ioaddr.nsect_addr);
                ioread8(ap->ioaddr.nsect_addr);
                ioread8(ap->ioaddr.nsect_addr);

                /* Now the data */

                if (write_data)
                        iowrite32_rep(ap->ioaddr.data_addr, buf, buflen >> 2);
                else
                        ioread32_rep(ap->ioaddr.data_addr, buf, buflen >> 2);

                if (unlikely(slop)) {
                        u32 pad;
                        if (write_data) {
                                memcpy(&pad, buf + buflen - slop, slop);
                                pad = le32_to_cpu(pad);
                                iowrite32(pad, ap->ioaddr.data_addr);
                        } else {
                                pad = ioread32(ap->ioaddr.data_addr);
                                pad = cpu_to_le16(pad);
                                memcpy(buf + buflen - slop, &pad, slop);
                        }
                }
                local_irq_restore(flags);
        }
        else
                ata_data_xfer_noirq(adev, buf, buflen, write_data);
}

static struct ata_port_operations pdc20230_port_ops = {
        .set_piomode    = pdc20230_set_piomode,

        .port_disable   = ata_port_disable,
        .tf_load        = ata_tf_load,
        .tf_read        = ata_tf_read,
        .check_status   = ata_check_status,
        .exec_command   = ata_exec_command,
        .dev_select     = ata_std_dev_select,

        .freeze         = ata_bmdma_freeze,
        .thaw           = ata_bmdma_thaw,
        .error_handler  = ata_bmdma_error_handler,
        .post_internal_cmd = ata_bmdma_post_internal_cmd,
        .cable_detect   = ata_cable_40wire,

        .qc_prep        = ata_qc_prep,
        .qc_issue       = ata_qc_issue_prot,

        .data_xfer      = pdc_data_xfer_vlb,

        .irq_handler    = ata_interrupt,
        .irq_clear      = ata_bmdma_irq_clear,
        .irq_on         = ata_irq_on,
        .irq_ack        = ata_irq_ack,

        .port_start     = ata_port_start,
};

/*
 *      Holtek 6560A support
 *
 *      This controller supports PIO0 to PIO2 (no IORDY even though higher timings
 *      can be loaded).
 */

static void ht6560a_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
        u8 active, recover;
        struct ata_timing t;

        /* Get the timing data in cycles. For now play safe at 50Mhz */
        ata_timing_compute(adev, adev->pio_mode, &t, 20000, 1000);

        active = FIT(t.active, 2, 15);
        recover = FIT(t.recover, 4, 15);

        inb(0x3E6);
        inb(0x3E6);
        inb(0x3E6);
        inb(0x3E6);

        iowrite8(recover << 4 | active, ap->ioaddr.device_addr);
        ioread8(ap->ioaddr.status_addr);
}

static struct ata_port_operations ht6560a_port_ops = {
        .set_piomode    = ht6560a_set_piomode,

        .port_disable   = ata_port_disable,
        .tf_load        = ata_tf_load,
        .tf_read        = ata_tf_read,
        .check_status   = ata_check_status,
        .exec_command   = ata_exec_command,
        .dev_select     = ata_std_dev_select,

        .freeze         = ata_bmdma_freeze,
        .thaw           = ata_bmdma_thaw,
        .error_handler  = ata_bmdma_error_handler,
        .post_internal_cmd = ata_bmdma_post_internal_cmd,
        .cable_detect   = ata_cable_40wire,

        .qc_prep        = ata_qc_prep,
        .qc_issue       = ata_qc_issue_prot,

        .data_xfer      = ata_data_xfer,        /* Check vlb/noirq */

        .irq_handler    = ata_interrupt,
        .irq_clear      = ata_bmdma_irq_clear,
        .irq_on         = ata_irq_on,
        .irq_ack        = ata_irq_ack,

        .port_start     = ata_port_start,
};

/*
 *      Holtek 6560B support
 *
 *      This controller supports PIO0 to PIO4. We honour the BIOS/jumper FIFO setting
 *      unless we see an ATAPI device in which case we force it off.
 *
 *      FIXME: need to implement 2nd channel support.
 */

static void ht6560b_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
        u8 active, recover;
        struct ata_timing t;

        /* Get the timing data in cycles. For now play safe at 50Mhz */
        ata_timing_compute(adev, adev->pio_mode, &t, 20000, 1000);

        active = FIT(t.active, 2, 15);
        recover = FIT(t.recover, 2, 16);
        recover &= 0x15;

        inb(0x3E6);
        inb(0x3E6);
        inb(0x3E6);
        inb(0x3E6);

        iowrite8(recover << 4 | active, ap->ioaddr.device_addr);

        if (adev->class != ATA_DEV_ATA) {
                u8 rconf = inb(0x3E6);
                if (rconf & 0x24) {
                        rconf &= ~ 0x24;
                        outb(rconf, 0x3E6);
                }
        }
        ioread8(ap->ioaddr.status_addr);
}

static struct ata_port_operations ht6560b_port_ops = {
        .set_piomode    = ht6560b_set_piomode,

        .port_disable   = ata_port_disable,
        .tf_load        = ata_tf_load,
        .tf_read        = ata_tf_read,
        .check_status   = ata_check_status,
        .exec_command   = ata_exec_command,
        .dev_select     = ata_std_dev_select,

        .freeze         = ata_bmdma_freeze,
        .thaw           = ata_bmdma_thaw,
        .error_handler  = ata_bmdma_error_handler,
        .post_internal_cmd = ata_bmdma_post_internal_cmd,
        .cable_detect   = ata_cable_40wire,

        .qc_prep        = ata_qc_prep,
        .qc_issue       = ata_qc_issue_prot,

        .data_xfer      = ata_data_xfer,        /* FIXME: Check 32bit and noirq */

        .irq_handler    = ata_interrupt,
        .irq_clear      = ata_bmdma_irq_clear,
        .irq_on         = ata_irq_on,
        .irq_ack        = ata_irq_ack,

        .port_start     = ata_port_start,
};

/*
 *      Opti core chipset helpers
 */

/**
 *      opti_syscfg     -       read OPTI chipset configuration
 *      @reg: Configuration register to read
 *
 *      Returns the value of an OPTI system board configuration register.
 */

static u8 opti_syscfg(u8 reg)
{
        unsigned long flags;
        u8 r;

        /* Uniprocessor chipset and must force cycles adjancent */
        local_irq_save(flags);
        outb(reg, 0x22);
        r = inb(0x24);
        local_irq_restore(flags);
        return r;
}

/*
 *      Opti 82C611A
 *
 *      This controller supports PIO0 to PIO3.
 */

static void opti82c611a_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
        u8 active, recover, setup;
        struct ata_timing t;
        struct ata_device *pair = ata_dev_pair(adev);
        int clock;
        int khz[4] = { 50000, 40000, 33000, 25000 };
        u8 rc;

        /* Enter configuration mode */
        ioread16(ap->ioaddr.error_addr);
        ioread16(ap->ioaddr.error_addr);
        iowrite8(3, ap->ioaddr.nsect_addr);

        /* Read VLB clock strapping */
        clock = 1000000000 / khz[ioread8(ap->ioaddr.lbah_addr) & 0x03];

        /* Get the timing data in cycles */
        ata_timing_compute(adev, adev->pio_mode, &t, clock, 1000);

        /* Setup timing is shared */
        if (pair) {
                struct ata_timing tp;
                ata_timing_compute(pair, pair->pio_mode, &tp, clock, 1000);

                ata_timing_merge(&t, &tp, &t, ATA_TIMING_SETUP);
        }

        active = FIT(t.active, 2, 17) - 2;
        recover = FIT(t.recover, 1, 16) - 1;
        setup = FIT(t.setup, 1, 4) - 1;

        /* Select the right timing bank for write timing */
        rc = ioread8(ap->ioaddr.lbal_addr);
        rc &= 0x7F;
        rc |= (adev->devno << 7);
        iowrite8(rc, ap->ioaddr.lbal_addr);

        /* Write the timings */
        iowrite8(active << 4 | recover, ap->ioaddr.error_addr);

        /* Select the right bank for read timings, also
           load the shared timings for address */
        rc = ioread8(ap->ioaddr.device_addr);
        rc &= 0xC0;
        rc |= adev->devno;      /* Index select */
        rc |= (setup << 4) | 0x04;
        iowrite8(rc, ap->ioaddr.device_addr);

        /* Load the read timings */
        iowrite8(active << 4 | recover, ap->ioaddr.data_addr);

        /* Ensure the timing register mode is right */
        rc = ioread8(ap->ioaddr.lbal_addr);
        rc &= 0x73;
        rc |= 0x84;
        iowrite8(rc, ap->ioaddr.lbal_addr);

        /* Exit command mode */
        iowrite8(0x83,  ap->ioaddr.nsect_addr);
}


static struct ata_port_operations opti82c611a_port_ops = {
        .set_piomode    = opti82c611a_set_piomode,

        .port_disable   = ata_port_disable,
        .tf_load        = ata_tf_load,
        .tf_read        = ata_tf_read,
        .check_status   = ata_check_status,
        .exec_command   = ata_exec_command,
        .dev_select     = ata_std_dev_select,

        .freeze         = ata_bmdma_freeze,
        .thaw           = ata_bmdma_thaw,
        .error_handler  = ata_bmdma_error_handler,
        .post_internal_cmd = ata_bmdma_post_internal_cmd,
        .cable_detect   = ata_cable_40wire,

        .qc_prep        = ata_qc_prep,
        .qc_issue       = ata_qc_issue_prot,

        .data_xfer      = ata_data_xfer,

        .irq_handler    = ata_interrupt,
        .irq_clear      = ata_bmdma_irq_clear,
        .irq_on         = ata_irq_on,
        .irq_ack        = ata_irq_ack,

        .port_start     = ata_port_start,
};

/*
 *      Opti 82C465MV
 *
 *      This controller supports PIO0 to PIO3. Unlike the 611A the MVB
 *      version is dual channel but doesn't have a lot of unique registers.
 */

static void opti82c46x_set_piomode(struct ata_port *ap, struct ata_device *adev)
{
        u8 active, recover, setup;
        struct ata_timing t;
        struct ata_device *pair = ata_dev_pair(adev);
        int clock;
        int khz[4] = { 50000, 40000, 33000, 25000 };
        u8 rc;
        u8 sysclk;

        /* Get the clock */
        sysclk = opti_syscfg(0xAC) & 0xC0;      /* BIOS set */

        /* Enter configuration mode */
        ioread16(ap->ioaddr.error_addr);
        ioread16(ap->ioaddr.error_addr);
        iowrite8(3, ap->ioaddr.nsect_addr);

        /* Read VLB clock strapping */
        clock = 1000000000 / khz[sysclk];

        /* Get the timing data in cycles */
        ata_timing_compute(adev, adev->pio_mode, &t, clock, 1000);

        /* Setup timing is shared */
        if (pair) {
                struct ata_timing tp;
                ata_timing_compute(pair, pair->pio_mode, &tp, clock, 1000);

                ata_timing_merge(&t, &tp, &t, ATA_TIMING_SETUP);
        }

        active = FIT(t.active, 2, 17) - 2;
        recover = FIT(t.recover, 1, 16) - 1;
        setup = FIT(t.setup, 1, 4) - 1;

        /* Select the right timing bank for write timing */
        rc = ioread8(ap->ioaddr.lbal_addr);
        rc &= 0x7F;
        rc |= (adev->devno << 7);
        iowrite8(rc, ap->ioaddr.lbal_addr);

        /* Write the timings */
        iowrite8(active << 4 | recover, ap->ioaddr.error_addr);

        /* Select the right bank for read timings, also
           load the shared timings for address */
        rc = ioread8(ap->ioaddr.device_addr);
        rc &= 0xC0;
        rc |= adev->devno;      /* Index select */
        rc |= (setup << 4) | 0x04;
        iowrite8(rc, ap->ioaddr.device_addr);

        /* Load the read timings */
        iowrite8(active << 4 | recover, ap->ioaddr.data_addr);

        /* Ensure the timing register mode is right */
        rc = ioread8(ap->ioaddr.lbal_addr);
        rc &= 0x73;
        rc |= 0x84;
        iowrite8(rc, ap->ioaddr.lbal_addr);

        /* Exit command mode */
        iowrite8(0x83,  ap->ioaddr.nsect_addr);

        /* We need to know this for quad device on the MVB */
        ap->host->private_data = ap;
}

/**
 *      opt82c465mv_qc_issue_prot       -       command issue
 *      @qc: command pending
 *
 *      Called when the libata layer is about to issue a command. We wrap
 *      this interface so that we can load the correct ATA timings. The
 *      MVB has a single set of timing registers and these are shared
 *      across channels. As there are two registers we really ought to
 *      track the last two used values as a sort of register window. For
 *      now we just reload on a channel switch. On the single channel
 *      setup this condition never fires so we do nothing extra.
 *
 *      FIXME: dual channel needs ->serialize support
 */

static unsigned int opti82c46x_qc_issue_prot(struct ata_queued_cmd *qc)
{
        struct ata_port *ap = qc->ap;
        struct ata_device *adev = qc->dev;

        /* If timings are set and for the wrong channel (2nd test is
           due to a libata shortcoming and will eventually go I hope) */
        if (ap->host->private_data != ap->host
            && ap->host->private_data != NULL)
                opti82c46x_set_piomode(ap, adev);

        return ata_qc_issue_prot(qc);
}

static struct ata_port_operations opti82c46x_port_ops = {
        .set_piomode    = opti82c46x_set_piomode,

        .port_disable   = ata_port_disable,
        .tf_load        = ata_tf_load,
        .tf_read        = ata_tf_read,
        .check_status   = ata_check_status,
        .exec_command   = ata_exec_command,
        .dev_select     = ata_std_dev_select,

        .freeze         = ata_bmdma_freeze,
        .thaw           = ata_bmdma_thaw,
        .error_handler  = ata_bmdma_error_handler,
        .post_internal_cmd = ata_bmdma_post_internal_cmd,
        .cable_detect   = ata_cable_40wire,

        .qc_prep        = ata_qc_prep,
        .qc_issue       = opti82c46x_qc_issue_prot,

        .data_xfer      = ata_data_xfer,

        .irq_handler    = ata_interrupt,
        .irq_clear      = ata_bmdma_irq_clear,
        .irq_on         = ata_irq_on,
        .irq_ack        = ata_irq_ack,

        .port_start     = ata_port_start,
};


/**
 *      legacy_init_one         -       attach a legacy interface
 *      @port: port number
 *      @io: I/O port start
 *      @ctrl: control port
 *      @irq: interrupt line
 *
 *      Register an ISA bus IDE interface. Such interfaces are PIO and we
 *      assume do not support IRQ sharing.
 */

static __init int legacy_init_one(int port, unsigned long io, unsigned long ctrl, int irq)
{
        struct legacy_data *ld = &legacy_data[nr_legacy_host];
        struct ata_host *host;
        struct ata_port *ap;
        struct platform_device *pdev;
        struct ata_port_operations *ops = &legacy_port_ops;
        void __iomem *io_addr, *ctrl_addr;
        int pio_modes = pio_mask;
        u32 mask = (1 << port);
        u32 iordy = (iordy_mask & mask) ? 0: ATA_FLAG_NO_IORDY;
        int ret;

        pdev = platform_device_register_simple(DRV_NAME, nr_legacy_host, NULL, 0);
        if (IS_ERR(pdev))
                return PTR_ERR(pdev);

        ret = -EBUSY;
        if (devm_request_region(&pdev->dev, io, 8, "pata_legacy") == NULL ||
            devm_request_region(&pdev->dev, ctrl, 1, "pata_legacy") == NULL)
                goto fail;

        ret = -ENOMEM;
        io_addr = devm_ioport_map(&pdev->dev, io, 8);
        ctrl_addr = devm_ioport_map(&pdev->dev, ctrl, 1);
        if (!io_addr || !ctrl_addr)
                goto fail;

        if (ht6560a & mask) {
                ops = &ht6560a_port_ops;
                pio_modes = 0x07;
                iordy = ATA_FLAG_NO_IORDY;
        }
        if (ht6560b & mask) {
                ops = &ht6560b_port_ops;
                pio_modes = 0x1F;
        }
        if (opti82c611a & mask) {
                ops = &opti82c611a_port_ops;
                pio_modes = 0x0F;
        }
        if (opti82c46x & mask) {
                ops = &opti82c46x_port_ops;
                pio_modes = 0x0F;
        }

        /* Probe for automatically detectable controllers */

        if (io == 0x1F0 && ops == &legacy_port_ops) {
                unsigned long flags;

                local_irq_save(flags);

                /* Probes */
                inb(0x1F5);
                outb(inb(0x1F2) | 0x80, 0x1F2);
                inb(0x1F2);
                inb(0x3F6);
                inb(0x3F6);
                inb(0x1F2);
                inb(0x1F2);

                if ((inb(0x1F2) & 0x80) == 0) {
                        /* PDC20230c or 20630 ? */
                        printk(KERN_INFO "PDC20230-C/20630 VLB ATA controller detected.\n");
                                pio_modes = 0x07;
                        ops = &pdc20230_port_ops;
                        iordy = ATA_FLAG_NO_IORDY;
                        udelay(100);
                        inb(0x1F5);
                } else {
                        outb(0x55, 0x1F2);
                        inb(0x1F2);
                        inb(0x1F2);
                        if (inb(0x1F2) == 0x00) {
                                printk(KERN_INFO "PDC20230-B VLB ATA controller detected.\n");
                        }
                }
                local_irq_restore(flags);
        }


        /* Chip does mode setting by command snooping */
        if (ops == &legacy_port_ops && (autospeed & mask))
                ops = &simple_port_ops;

        ret = -ENOMEM;
        host = ata_host_alloc(&pdev->dev, 1);
        if (!host)
                goto fail;
        ap = host->ports[0];

        ap->ops = ops;
        ap->pio_mask = pio_modes;
        ap->flags |= ATA_FLAG_SLAVE_POSS | iordy;
        ap->ioaddr.cmd_addr = io_addr;
        ap->ioaddr.altstatus_addr = ctrl_addr;
        ap->ioaddr.ctl_addr = ctrl_addr;
        ata_std_ports(&ap->ioaddr);
        ap->private_data = ld;

        ret = ata_host_activate(host, irq, ata_interrupt, 0, &legacy_sht);
        if (ret)
                goto fail;

        legacy_host[nr_legacy_host++] = dev_get_drvdata(&pdev->dev);
        ld->platform_dev = pdev;
        return 0;

fail:
        platform_device_unregister(pdev);
        return ret;
}

/**
 *      legacy_check_special_cases      -       ATA special cases
 *      @p: PCI device to check
 *      @master: set this if we find an ATA master
 *      @master: set this if we find an ATA secondary
 *
 *      A small number of vendors implemented early PCI ATA interfaces on bridge logic
 *      without the ATA interface being PCI visible. Where we have a matching PCI driver
 *      we must skip the relevant device here. If we don't know about it then the legacy
 *      driver is the right driver anyway.
 */

static void legacy_check_special_cases(struct pci_dev *p, int *primary, int *secondary)
{
        /* Cyrix CS5510 pre SFF MWDMA ATA on the bridge */
        if (p->vendor == 0x1078 && p->device == 0x0000) {
                *primary = *secondary = 1;
                return;
        }
        /* Cyrix CS5520 pre SFF MWDMA ATA on the bridge */
        if (p->vendor == 0x1078 && p->device == 0x0002) {
                *primary = *secondary = 1;
                return;
        }
        /* Intel MPIIX - PIO ATA on non PCI side of bridge */
        if (p->vendor == 0x8086 && p->device == 0x1234) {
                u16 r;
                pci_read_config_word(p, 0x6C, &r);
                if (r & 0x8000) {       /* ATA port enabled */
                        if (r & 0x4000)
                                *secondary = 1;
                        else
                                *primary = 1;
                }
                return;
        }
}


/**
 *      legacy_init             -       attach legacy interfaces
 *
 *      Attach legacy IDE interfaces by scanning the usual IRQ/port suspects.
 *      Right now we do not scan the ide0 and ide1 address but should do so
 *      for non PCI systems or systems with no PCI IDE legacy mode devices.
 *      If you fix that note there are special cases to consider like VLB
 *      drivers and CS5510/20.
 */

static __init int legacy_init(void)
{
        int i;
        int ct = 0;
        int primary = 0;
        int secondary = 0;
        int last_port = NR_HOST;

        struct pci_dev *p = NULL;

        for_each_pci_dev(p) {
                int r;
                /* Check for any overlap of the system ATA mappings. Native mode controllers
                   stuck on these addresses or some devices in 'raid' mode won't be found by
                   the storage class test */
                for (r = 0; r < 6; r++) {
                        if (pci_resource_start(p, r) == 0x1f0)
                                primary = 1;
                        if (pci_resource_start(p, r) == 0x170)
                                secondary = 1;
                }
                /* Check for special cases */
                legacy_check_special_cases(p, &primary, &secondary);

                /* If PCI bus is present then don't probe for tertiary legacy ports */
                if (probe_all == 0)
                        last_port = 2;
        }

        /* If an OPTI 82C46X is present find out where the channels are */
        if (opti82c46x) {
                static const char *optis[4] = {
                        "3/463MV", "5MV",
                        "5MVA", "5MVB"
                };
                u8 chans = 1;
                u8 ctrl = (opti_syscfg(0x30) & 0xC0) >> 6;

                opti82c46x = 3; /* Assume master and slave first */
                printk(KERN_INFO DRV_NAME ": Opti 82C46%s chipset support.\n", optis[ctrl]);
                if (ctrl == 3)
                        chans = (opti_syscfg(0x3F) & 0x20) ? 2 : 1;
                ctrl = opti_syscfg(0xAC);
                /* Check enabled and this port is the 465MV port. On the
                   MVB we may have two channels */
                if (ctrl & 8) {
                        if (ctrl & 4)
                                opti82c46x = 2; /* Slave */
                        else
                                opti82c46x = 1; /* Master */
                        if (chans == 2)
                                opti82c46x = 3; /* Master and Slave */
                }       /* Slave only */
                else if (chans == 1)
                        opti82c46x = 1;
        }

        for (i = 0; i < last_port; i++) {
                /* Skip primary if we have seen a PCI one */
                if (i == 0 && primary == 1)
                        continue;
                /* Skip secondary if we have seen a PCI one */
                if (i == 1 && secondary == 1)
                        continue;
                if (legacy_init_one(i, legacy_port[i],
                                   legacy_port[i] + 0x0206,
                                   legacy_irq[i]) == 0)
                        ct++;
        }
        if (ct != 0)
                return 0;
        return -ENODEV;
}

static __exit void legacy_exit(void)
{
        int i;

        for (i = 0; i < nr_legacy_host; i++) {
                struct legacy_data *ld = &legacy_data[i];

                ata_host_detach(legacy_host[i]);
                platform_device_unregister(ld->platform_dev);
                if (ld->timing)
                        release_region(ld->timing, 2);
        }
}

MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("low-level driver for legacy ATA");
MODULE_LICENSE("GPL");
MODULE_VERSION(DRV_VERSION);

module_param(probe_all, int, 0);
module_param(autospeed, int, 0);
module_param(ht6560a, int, 0);
module_param(ht6560b, int, 0);
module_param(opti82c611a, int, 0);
module_param(opti82c46x, int, 0);
module_param(pio_mask, int, 0);
module_param(iordy_mask, int, 0);

module_init(legacy_init);
module_exit(legacy_exit);