/*
* ata_piix.c - Intel PATA/SATA controllers
*
* Maintained by: Jeff Garzik <jgarzik@pobox.com>
* Please ALWAYS copy linux-ide@vger.kernel.org
* on emails.
*
*
* Copyright 2003-2005 Red Hat Inc
* Copyright 2003-2005 Jeff Garzik
*
*
* Copyright header from piix.c:
*
* Copyright (C) 1998-1999 Andrzej Krzysztofowicz, Author and Maintainer
* Copyright (C) 1998-2000 Andre Hedrick <andre@linux-ide.org>
* Copyright (C) 2003 Red Hat Inc <alan@redhat.com>
*
*
* 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.
*
*
* libata documentation is available via 'make {ps|pdf}docs',
* as Documentation/DocBook/libata.*
*
* Hardware documentation available at http://developer.intel.com/
*
*/
#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.h"
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#define DRV_NAME "ata_piix"
#define DRV_VERSION "1.04"
enum {
PIIX_IOCFG = 0x54, /* IDE I/O configuration register */
ICH5_PMR = 0x90, /* port mapping register */
ICH5_PCS = 0x92, /* port control and status */
PIIX_SCC = 0x0A, /* sub-class code register */
PIIX_FLAG_AHCI = (1 << 28), /* AHCI possible */
PIIX_FLAG_CHECKINTR = (1 << 29), /* make sure PCI INTx enabled */
PIIX_FLAG_COMBINED = (1 << 30), /* combined mode possible */
/* combined mode. if set, PATA is channel 0.
* if clear, PATA is channel 1.
*/
PIIX_COMB_PATA_P0 = (1 << 1),
PIIX_COMB = (1 << 2), /* combined mode enabled? */
PIIX_PORT_PRESENT = (1 << 0),
PIIX_PORT_ENABLED = (1 << 4),
PIIX_80C_PRI = (1 << 5) | (1 << 4),
PIIX_80C_SEC = (1 << 7) | (1 << 6),
ich5_pata = 0,
ich5_sata = 1,
piix4_pata = 2,
ich6_sata = 3,
ich6_sata_rm = 4,
ich7_sata = 5,
esb2_sata = 6,
PIIX_AHCI_DEVICE = 6,
};
static int piix_init_one (struct pci_dev *pdev,
const struct pci_device_id *ent);
static void piix_pata_phy_reset(struct ata_port *ap);
static void piix_sata_phy_reset(struct ata_port *ap);
static void piix_set_piomode (struct ata_port *ap, struct ata_device *adev);
static void piix_set_dmamode (struct ata_port *ap, struct ata_device *adev);
static unsigned int in_module_init = 1;
static struct pci_device_id piix_pci_tbl[] = {
#ifdef ATA_ENABLE_PATA
{ 0x8086, 0x7111, PCI_ANY_ID, PCI_ANY_ID, 0, 0, piix4_pata },
{ 0x8086, 0x24db, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich5_pata },
{ 0x8086, 0x25a2, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich5_pata },
#endif
/* NOTE: The following PCI ids must be kept in sync with the
* list in drivers/pci/quirks.c.
*/
{ 0x8086, 0x24d1, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich5_sata },
{ 0x8086, 0x24df, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich5_sata },
{ 0x8086, 0x25a3, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich5_sata },
{ 0x8086, 0x25b0, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich5_sata },
{ 0x8086, 0x2651, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich6_sata },
{ 0x8086, 0x2652, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich6_sata_rm },
{ 0x8086, 0x2653, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich6_sata_rm },
{ 0x8086, 0x27c0, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich7_sata },
{ 0x8086, 0x27c4, PCI_ANY_ID, PCI_ANY_ID, 0, 0, ich7_sata },
{ 0x8086, 0x2680, PCI_ANY_ID, PCI_ANY_ID, 0, 0, esb2_sata },
{ } /* terminate list */
};
static struct pci_driver piix_pci_driver = {
.name = DRV_NAME,
.id_table = piix_pci_tbl,
.probe = piix_init_one,
.remove = ata_pci_remove_one,
};
static Scsi_Host_Template piix_sht = {
.module = THIS_MODULE,
.name = DRV_NAME,
.ioctl = ata_scsi_ioctl,
.queuecommand = ata_scsi_queuecmd,
.eh_strategy_handler = ata_scsi_error,
.can_queue = ATA_DEF_QUEUE,
.this_id = ATA_SHT_THIS_ID,
.sg_tablesize = LIBATA_MAX_PRD,
.max_sectors = ATA_MAX_SECTORS,
.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,
.bios_param = ata_std_bios_param,
.ordered_flush = 1,
};
static struct ata_port_operations piix_pata_ops = {
.port_disable = ata_port_disable,
.set_piomode = piix_set_piomode,
.set_dmamode = piix_set_dmamode,
.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,
.phy_reset = piix_pata_phy_reset,
.bmdma_setup = ata_bmdma_setup,
.bmdma_start = ata_bmdma_start,
.bmdma_stop = ata_bmdma_stop,
.bmdma_status = ata_bmdma_status,
.qc_prep = ata_qc_prep,
.qc_issue = ata_qc_issue_prot,
.eng_timeout = ata_eng_timeout,
.irq_handler = ata_interrupt,
.irq_clear = ata_bmdma_irq_clear,
.port_start = ata_port_start,
.port_stop = ata_port_stop,
.host_stop = ata_host_stop,
};
static struct ata_port_operations piix_sata_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,
.phy_reset = piix_sata_phy_reset,
.bmdma_setup = ata_bmdma_setup,
.bmdma_start = ata_bmdma_start,
.bmdma_stop = ata_bmdma_stop,
.bmdma_status = ata_bmdma_status,
.qc_prep = ata_qc_prep,
.qc_issue = ata_qc_issue_prot,
.eng_timeout = ata_eng_timeout,
.irq_handler = ata_interrupt,
.irq_clear = ata_bmdma_irq_clear,
.port_start = ata_port_start,
.port_stop = ata_port_stop,
.host_stop = ata_host_stop,
};
static struct ata_port_info piix_port_info[] = {
/* ich5_pata */
{
.sht = &piix_sht,
.host_flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST |
PIIX_FLAG_CHECKINTR,
.pio_mask = 0x1f, /* pio0-4 */
#if 0
.mwdma_mask = 0x06, /* mwdma1-2 */
#else
.mwdma_mask = 0x00, /* mwdma broken */
#endif
.udma_mask = 0x3f, /* udma0-5 */
.port_ops = &piix_pata_ops,
},
/* ich5_sata */
{
.sht = &piix_sht,
.host_flags = ATA_FLAG_SATA | ATA_FLAG_SRST |
PIIX_FLAG_COMBINED | PIIX_FLAG_CHECKINTR,
.pio_mask = 0x1f, /* pio0-4 */
.mwdma_mask = 0x07, /* mwdma0-2 */
.udma_mask = 0x7f, /* udma0-6 */
.port_ops = &piix_sata_ops,
},
/* piix4_pata */
{
.sht = &piix_sht,
.host_flags = ATA_FLAG_SLAVE_POSS | ATA_FLAG_SRST,
.pio_mask = 0x1f, /* pio0-4 */
#if 0
.mwdma_mask = 0x06, /* mwdma1-2 */
#else
.mwdma_mask = 0x00, /* mwdma broken */
#endif
.udma_mask = ATA_UDMA_MASK_40C,
.port_ops = &piix_pata_ops,
},
/* ich6_sata */
{
.sht = &piix_sht,
.host_flags = ATA_FLAG_SATA | ATA_FLAG_SRST |
PIIX_FLAG_COMBINED | PIIX_FLAG_CHECKINTR |
ATA_FLAG_SLAVE_POSS,
.pio_mask = 0x1f, /* pio0-4 */
.mwdma_mask = 0x07, /* mwdma0-2 */
.udma_mask = 0x7f, /* udma0-6 */
.port_ops = &piix_sata_ops,
},
/* ich6_sata_rm */
{
.sht = &piix_sht,
.host_flags = ATA_FLAG_SATA | ATA_FLAG_SRST |
PIIX_FLAG_COMBINED | PIIX_FLAG_CHECKINTR |
ATA_FLAG_SLAVE_POSS | PIIX_FLAG_AHCI,
.pio_mask = 0x1f, /* pio0-4 */
.mwdma_mask = 0x07, /* mwdma0-2 */
.udma_mask = 0x7f, /* udma0-6 */
.port_ops = &piix_sata_ops,
},
/* ich7_sata */
{
.sht = &piix_sht,
.host_flags = ATA_FLAG_SATA | ATA_FLAG_SRST |
PIIX_FLAG_COMBINED | PIIX_FLAG_CHECKINTR |
ATA_FLAG_SLAVE_POSS | PIIX_FLAG_AHCI,
.pio_mask = 0x1f, /* pio0-4 */
.mwdma_mask = 0x07, /* mwdma0-2 */
.udma_mask = 0x7f, /* udma0-6 */
.port_ops = &piix_sata_ops,
},
/* esb2_sata */
{
.sht = &piix_sht,
.host_flags = ATA_FLAG_SATA | ATA_FLAG_SRST |
PIIX_FLAG_COMBINED | PIIX_FLAG_CHECKINTR |
ATA_FLAG_SLAVE_POSS | PIIX_FLAG_AHCI,
.pio_mask = 0x1f, /* pio0-4 */
.mwdma_mask = 0x07, /* mwdma0-2 */
.udma_mask = 0x7f, /* udma0-6 */
.port_ops = &piix_sata_ops,
},
};
static struct pci_bits piix_enable_bits[] = {
{ 0x41U, 1U, 0x80UL, 0x80UL }, /* port 0 */
{ 0x43U, 1U, 0x80UL, 0x80UL }, /* port 1 */
};
MODULE_AUTHOR("Andre Hedrick, Alan Cox, Andrzej Krzysztofowicz, Jeff Garzik");
MODULE_DESCRIPTION("SCSI low-level driver for Intel PIIX/ICH ATA controllers");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, piix_pci_tbl);
MODULE_VERSION(DRV_VERSION);
/**
* piix_pata_cbl_detect - Probe host controller cable detect info
* @ap: Port for which cable detect info is desired
*
* Read 80c cable indicator from ATA PCI device's PCI config
* register. This register is normally set by firmware (BIOS).
*
* LOCKING:
* None (inherited from caller).
*/
static void piix_pata_cbl_detect(struct ata_port *ap)
{
struct pci_dev *pdev = to_pci_dev(ap->host_set->dev);
u8 tmp, mask;
/* no 80c support in host controller? */
if ((ap->udma_mask & ~ATA_UDMA_MASK_40C) == 0)
goto cbl40;
/* check BIOS cable detect results */
mask = ap->hard_port_no == 0 ? PIIX_80C_PRI : PIIX_80C_SEC;
pci_read_config_byte(pdev, PIIX_IOCFG, &tmp);
if ((tmp & mask) == 0)
goto cbl40;
ap->cbl = ATA_CBL_PATA80;
return;
cbl40:
ap->cbl = ATA_CBL_PATA40;
ap->udma_mask &= ATA_UDMA_MASK_40C;
}
/**
* piix_pata_phy_reset - Probe specified port on PATA host controller
* @ap: Port to probe
*
* Probe PATA phy.
*
* LOCKING:
* None (inherited from caller).
*/
static void piix_pata_phy_reset(struct ata_port *ap)
{
struct pci_dev *pdev = to_pci_dev(ap->host_set->dev);
if (!pci_test_config_bits(pdev, &piix_enable_bits[ap->hard_port_no])) {
ata_port_disable(ap);
printk(KERN_INFO "ata%u: port disabled. ignoring.\n", ap->id);
return;
}
piix_pata_cbl_detect(ap);
ata_port_probe(ap);
ata_bus_reset(ap);
}
/**
* piix_sata_probe - Probe PCI device for present SATA devices
* @ap: Port associated with the PCI device we wish to probe
*
* Reads SATA PCI device's PCI config register Port Configuration
* and Status (PCS) to determine port and device availability.
*
* LOCKING:
* None (inherited from caller).
*
* RETURNS:
* Non-zero if device detected, zero otherwise.
*/
static int piix_sata_probe (struct ata_port *ap)
{
struct pci_dev *pdev = to_pci_dev(ap->host_set->dev);
int combined = (ap->flags & ATA_FLAG_SLAVE_POSS);
int orig_mask, mask, i;
u8 pcs;
mask = (PIIX_PORT_PRESENT << ap->hard_port_no) |
(PIIX_PORT_ENABLED << ap->hard_port_no);
pci_read_config_byte(pdev, ICH5_PCS, &pcs);
orig_mask = (int) pcs & 0xff;
/* TODO: this is vaguely wrong for ICH6 combined mode,
* where only two of the four SATA ports are mapped
* onto a single ATA channel. It is also vaguely inaccurate
* for ICH5, which has only two ports. However, this is ok,
* as further device presence detection code will handle
* any false positives produced here.
*/
for (i = 0; i < 4; i++) {
mask = (PIIX_PORT_PRESENT << i) | (PIIX_PORT_ENABLED << i);
if ((orig_mask & mask) == mask)
if (combined || (i == ap->hard_port_no))
return 1;
}
return 0;
}
/**
* piix_sata_phy_reset - Probe specified port on SATA host controller
* @ap: Port to probe
*
* Probe SATA phy.
*
* LOCKING:
* None (inherited from caller).
*/
static void piix_sata_phy_reset(struct ata_port *ap)
{
if (!piix_sata_probe(ap)) {
ata_port_disable(ap);
printk(KERN_INFO "ata%u: SATA port has no device.\n", ap->id);
return;
}
ap->cbl = ATA_CBL_SATA;
ata_port_probe(ap);
ata_bus_reset(ap);
}
/**
* piix_set_piomode - Initialize host controller PATA PIO timings
* @ap: Port whose timings we are configuring
* @adev: um
* @pio: PIO mode, 0 - 4
*
* Set PIO mode for device, in host controller PCI config space.
*
* LOCKING:
* None (inherited from caller).
*/
static void piix_set_piomode (struct ata_port *ap, struct ata_device *adev)
{
unsigned int pio = adev->pio_mode - XFER_PIO_0;
struct pci_dev *dev = to_pci_dev(ap->host_set->dev);
unsigned int is_slave = (adev->devno != 0);
unsigned int master_port= ap->hard_port_no ? 0x42 : 0x40;
unsigned int slave_port = 0x44;
u16 master_data;
u8 slave_data;
static const /* ISP RTC */
u8 timings[][2] = { { 0, 0 },
{ 0, 0 },
{ 1, 0 },
{ 2, 1 },
{ 2, 3 }, };
pci_read_config_word(dev, master_port, &master_data);
if (is_slave) {
master_data |= 0x4000;
/* enable PPE, IE and TIME */
master_data |= 0x0070;
pci_read_config_byte(dev, slave_port, &slave_data);
slave_data &= (ap->hard_port_no ? 0x0f : 0xf0);
slave_data |=
(timings[pio][0] << 2) |
(timings[pio][1] << (ap->hard_port_no ? 4 : 0));
} else {
master_data &= 0xccf8;
/* enable PPE, IE and TIME */
master_data |= 0x0007;
master_data |=
(timings[pio][0] << 12) |
(timings[pio][1] << 8);
}
pci_write_config_word(dev, master_port, master_data);
if (is_slave)
pci_write_config_byte(dev, slave_port, slave_data);
}
/**
* piix_set_dmamode - Initialize host controller PATA PIO timings
* @ap: Port whose timings we are configuring
* @adev: um
* @udma: udma mode, 0 - 6
*
* Set UDMA mode for device, in host controller PCI config space.
*
* LOCKING:
* None (inherited from caller).
*/
static void piix_set_dmamode (struct ata_port *ap, struct ata_device *adev)
{
unsigned int udma = adev->dma_mode; /* FIXME: MWDMA too */
struct pci_dev *dev = to_pci_dev(ap->host_set->dev);
u8 maslave = ap->hard_port_no ? 0x42 : 0x40;
u8 speed = udma;
unsigned int drive_dn = (ap->hard_port_no ? 2 : 0) + adev->devno;
int a_speed = 3 << (drive_dn * 4);
int u_flag = 1 << drive_dn;
int v_flag = 0x01 << drive_dn;
int w_flag = 0x10 << drive_dn;
int u_speed = 0;
int sitre;
u16 reg4042, reg4a;
u8 reg48, reg54, reg55;
pci_read_config_word(dev, maslave, ®4042);
DPRINTK("reg4042 = 0x%04x\n", reg4042);
sitre = (reg4042 & 0x4000) ? 1 : 0;
pci_read_config_byte(dev, 0x48, ®48);
pci_read_config_word(dev, 0x4a, ®4a);
pci_read_config_byte(dev, 0x54, ®54);
pci_read_config_byte(dev, 0x55, ®55);
switch(speed) {
case XFER_UDMA_4:
case XFER_UDMA_2: u_speed = 2 << (drive_dn * 4); break;
case XFER_UDMA_6:
case XFER_UDMA_5:
case XFER_UDMA_3:
case XFER_UDMA_1: u_speed = 1 << (drive_dn * 4); break;
case XFER_UDMA_0: u_speed = 0 << (drive_dn * 4); break;
case XFER_MW_DMA_2:
case XFER_MW_DMA_1: break;
default:
BUG();
return;
}
if (speed >= XFER_UDMA_0) {
if (!(reg48 & u_flag))
pci_write_config_byte(dev, 0x48, reg48 | u_flag);
if (speed == XFER_UDMA_5) {
pci_write_config_byte(dev, 0x55, (u8) reg55|w_flag);
} else {
pci_write_config_byte(dev, 0x55, (u8) reg55 & ~w_flag);
}
if ((reg4a & a_speed) != u_speed)
pci_write_config_word(dev, 0x4a, (reg4a & ~a_speed) | u_speed);
if (speed > XFER_UDMA_2) {
if (!(reg54 & v_flag))
pci_write_config_byte(dev, 0x54, reg54 | v_flag);
} else
pci_write_config_byte(dev, 0x54, reg54 & ~v_flag);
} else {
if (reg48 & u_flag)
pci_write_config_byte(dev, 0x48, reg48 & ~u_flag);
if (reg4a & a_speed)
pci_write_config_word(dev, 0x4a, reg4a & ~a_speed);
if (reg54 & v_flag)
pci_write_config_byte(dev, 0x54, reg54 & ~v_flag);
if (reg55 & w_flag)
pci_write_config_byte(dev, 0x55, (u8) reg55 & ~w_flag);
}
}
/* move to PCI layer, integrate w/ MSI stuff */
static void pci_enable_intx(struct pci_dev *pdev)
{
u16 pci_command;
pci_read_config_word(pdev, PCI_COMMAND, &pci_command);
if (pci_command & PCI_COMMAND_INTX_DISABLE) {
pci_command &= ~PCI_COMMAND_INTX_DISABLE;
pci_write_config_word(pdev, PCI_COMMAND, pci_command);
}
}
#define AHCI_PCI_BAR 5
#define AHCI_GLOBAL_CTL 0x04
#define AHCI_ENABLE (1 << 31)
static int piix_disable_ahci(struct pci_dev *pdev)
{
void *mmio;
unsigned long addr;
u32 tmp;
int rc = 0;
/* BUG: pci_enable_device has not yet been called. This
* works because this device is usually set up by BIOS.
*/
addr = pci_resource_start(pdev, AHCI_PCI_BAR);
if (!addr || !pci_resource_len(pdev, AHCI_PCI_BAR))
return 0;
mmio = ioremap(addr, 64);
if (!mmio)
return -ENOMEM;
tmp = readl(mmio + AHCI_GLOBAL_CTL);
if (tmp & AHCI_ENABLE) {
tmp &= ~AHCI_ENABLE;
writel(tmp, mmio + AHCI_GLOBAL_CTL);
tmp = readl(mmio + AHCI_GLOBAL_CTL);
if (tmp & AHCI_ENABLE)
rc = -EIO;
}
iounmap(mmio);
return rc;
}
/**
* piix_init_one - Register PIIX ATA PCI device with kernel services
* @pdev: PCI device to register
* @ent: Entry in piix_pci_tbl matching with @pdev
*
* Called from kernel PCI layer. We probe for combined mode (sigh),
* and then hand over control to libata, for it to do the rest.
*
* LOCKING:
* Inherited from PCI layer (may sleep).
*
* RETURNS:
* Zero on success, or -ERRNO value.
*/
static int piix_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
{
static int printed_version;
struct ata_port_info *port_info[2];
unsigned int combined = 0, n_ports = 1;
unsigned int pata_chan = 0, sata_chan = 0;
if (!printed_version++)
printk(KERN_DEBUG DRV_NAME " version " DRV_VERSION "\n");
/* no hotplugging support (FIXME) */
if (!in_module_init)
return -ENODEV;
port_info[0] = &piix_port_info[ent->driver_data];
port_info[1] = NULL;
if (port_info[0]->host_flags & PIIX_FLAG_AHCI) {
u8 tmp;
pci_read_config_byte(pdev, PIIX_SCC, &tmp);
if (tmp == PIIX_AHCI_DEVICE) {
int rc = piix_disable_ahci(pdev);
if (rc)
return rc;
}
}
if (port_info[0]->host_flags & PIIX_FLAG_COMBINED) {
u8 tmp;
pci_read_config_byte(pdev, ICH5_PMR, &tmp);
if (tmp & PIIX_COMB) {
combined = 1;
if (tmp & PIIX_COMB_PATA_P0)
sata_chan = 1;
else
pata_chan = 1;
}
}
/* On ICH5, some BIOSen disable the interrupt using the
* PCI_COMMAND_INTX_DISABLE bit added in PCI 2.3.
* On ICH6, this bit has the same effect, but only when
* MSI is disabled (and it is disabled, as we don't use
* message-signalled interrupts currently).
*/
if (port_info[0]->host_flags & PIIX_FLAG_CHECKINTR)
pci_enable_intx(pdev);
if (combined) {
port_info[sata_chan] = &piix_port_info[ent->driver_data];
port_info[sata_chan]->host_flags |= ATA_FLAG_SLAVE_POSS;
port_info[pata_chan] = &piix_port_info[ich5_pata];
n_ports++;
printk(KERN_WARNING DRV_NAME ": combined mode detected\n");
}
return ata_pci_init_one(pdev, port_info, n_ports);
}
static int __init piix_init(void)
{
int rc;
DPRINTK("pci_module_init\n");
rc = pci_module_init(&piix_pci_driver);
if (rc)
return rc;
in_module_init = 0;
DPRINTK("done\n");
return 0;
}
static void __exit piix_exit(void)
{
pci_unregister_driver(&piix_pci_driver);
}
module_init(piix_init);
module_exit(piix_exit);
