android_kernel_xiaomi_sm8350/drivers/scsi/ata_piix.c
Jeff Garzik aa8f0dc6c3 libata: Fix use-after-iounmap
Jens Axboe pointed out that the iounmap() call in libata was occurring
too early, and some drivers (ahci, probably others) were using ioremap'd
memory after it had been unmapped.

The patch should address that problem by way of improving the libata
driver API:

* move ->host_stop() call after all ->port_stop() calls have occurred.

* create default helper function ata_host_stop(), and move iounmap()
call there.

* add ->host_stop_prewalk() hook, use it in sata_qstor.c (hi Mark).
sata_qstor appears to require the host-stop-before-port-stop ordering
that existed prior to applying the attached patch.
2005-05-26 21:54:27 -04:00

707 lines
18 KiB
C

/*
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 2003-2004 Red Hat Inc
Copyright 2003-2004 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>
May be copied or modified under the terms of the GNU General Public License
*/
#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 "1.03"
enum {
PIIX_IOCFG = 0x54, /* IDE I/O configuration register */
ICH5_PMR = 0x90, /* port mapping register */
ICH5_PCS = 0x92, /* port control and status */
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,
};
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, &reg4042);
DPRINTK("reg4042 = 0x%04x\n", reg4042);
sitre = (reg4042 & 0x4000) ? 1 : 0;
pci_read_config_byte(dev, 0x48, &reg48);
pci_read_config_word(dev, 0x4a, &reg4a);
pci_read_config_byte(dev, 0x54, &reg54);
pci_read_config_byte(dev, 0x55, &reg55);
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) {
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);
}
/**
* piix_init -
*
* LOCKING:
*
* RETURNS:
*
*/
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;
}
/**
* piix_exit -
*
* LOCKING:
*
*/
static void __exit piix_exit(void)
{
pci_unregister_driver(&piix_pci_driver);
}
module_init(piix_init);
module_exit(piix_exit);