kernel-ark/drivers/ata/pata_efar.c
Bartlomiej Zolnierkiewicz 303f1a76ae [libata] pata_efar: add locking for parallel scanning
Add clearing of UDMA enable bit also for PIO modes and then add
extra locking for parallel scanning.

This is similar change as commit 60c3be3 for ata_piix host driver
and while pata_efar doesn't enable parallel scan yet the race could
probably also be triggered by requesting re-scanning of both ports
at the same time using SCSI sysfs interface.

[Ported to current kernel without other patch dependancies by
 Alan Cox]

Original is
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>

This one is
Signed-off-by: Alan Cox <alan@linux.intel.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2010-03-01 15:04:58 -05:00

319 lines
8.2 KiB
C

/*
* pata_efar.c - EFAR PIIX clone controller driver
*
* (C) 2005 Red Hat
* (C) 2009-2010 Bartlomiej Zolnierkiewicz
*
* Some parts based on ata_piix.c by Jeff Garzik and others.
*
* The EFAR is a PIIX4 clone with UDMA66 support. Unlike the later
* Intel ICH controllers the EFAR widened the UDMA mode register bits
* and doesn't require the funky clock selection.
*/
#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 <linux/device.h>
#include <scsi/scsi_host.h>
#include <linux/libata.h>
#include <linux/ata.h>
#define DRV_NAME "pata_efar"
#define DRV_VERSION "0.4.5"
/**
* efar_pre_reset - Enable bits
* @link: ATA link
* @deadline: deadline jiffies for the operation
*
* Perform cable detection for the EFAR ATA interface. This is
* different to the PIIX arrangement
*/
static int efar_pre_reset(struct ata_link *link, unsigned long deadline)
{
static const struct pci_bits efar_enable_bits[] = {
{ 0x41U, 1U, 0x80UL, 0x80UL }, /* port 0 */
{ 0x43U, 1U, 0x80UL, 0x80UL }, /* port 1 */
};
struct ata_port *ap = link->ap;
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
if (!pci_test_config_bits(pdev, &efar_enable_bits[ap->port_no]))
return -ENOENT;
return ata_sff_prereset(link, deadline);
}
/**
* efar_cable_detect - check for 40/80 pin
* @ap: Port
*
* Perform cable detection for the EFAR ATA interface. This is
* different to the PIIX arrangement
*/
static int efar_cable_detect(struct ata_port *ap)
{
struct pci_dev *pdev = to_pci_dev(ap->host->dev);
u8 tmp;
pci_read_config_byte(pdev, 0x47, &tmp);
if (tmp & (2 >> ap->port_no))
return ATA_CBL_PATA40;
return ATA_CBL_PATA80;
}
static DEFINE_SPINLOCK(efar_lock);
/**
* efar_set_piomode - Initialize host controller PATA PIO timings
* @ap: Port whose timings we are configuring
* @adev: um
*
* Set PIO mode for device, in host controller PCI config space.
*
* LOCKING:
* None (inherited from caller).
*/
static void efar_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->dev);
unsigned int idetm_port= ap->port_no ? 0x42 : 0x40;
unsigned long flags;
u16 idetm_data;
u8 udma_enable;
int control = 0;
/*
* See Intel Document 298600-004 for the timing programing rules
* for PIIX/ICH. The EFAR is a clone so very similar
*/
static const /* ISP RTC */
u8 timings[][2] = { { 0, 0 },
{ 0, 0 },
{ 1, 0 },
{ 2, 1 },
{ 2, 3 }, };
if (pio > 1)
control |= 1; /* TIME */
if (ata_pio_need_iordy(adev)) /* PIO 3/4 require IORDY */
control |= 2; /* IE */
/* Intel specifies that the prefetch/posting is for disk only */
if (adev->class == ATA_DEV_ATA)
control |= 4; /* PPE */
spin_lock_irqsave(&efar_lock, flags);
pci_read_config_word(dev, idetm_port, &idetm_data);
/* Set PPE, IE, and TIME as appropriate */
if (adev->devno == 0) {
idetm_data &= 0xCCF0;
idetm_data |= control;
idetm_data |= (timings[pio][0] << 12) |
(timings[pio][1] << 8);
} else {
int shift = 4 * ap->port_no;
u8 slave_data;
idetm_data &= 0xFF0F;
idetm_data |= (control << 4);
/* Slave timing in separate register */
pci_read_config_byte(dev, 0x44, &slave_data);
slave_data &= ap->port_no ? 0x0F : 0xF0;
slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << shift;
pci_write_config_byte(dev, 0x44, slave_data);
}
idetm_data |= 0x4000; /* Ensure SITRE is set */
pci_write_config_word(dev, idetm_port, idetm_data);
pci_read_config_byte(dev, 0x48, &udma_enable);
udma_enable &= ~(1 << (2 * ap->port_no + adev->devno));
pci_write_config_byte(dev, 0x48, udma_enable);
spin_unlock_irqrestore(&efar_lock, flags);
}
/**
* efar_set_dmamode - Initialize host controller PATA DMA timings
* @ap: Port whose timings we are configuring
* @adev: Device to program
*
* Set UDMA/MWDMA mode for device, in host controller PCI config space.
*
* LOCKING:
* None (inherited from caller).
*/
static void efar_set_dmamode (struct ata_port *ap, struct ata_device *adev)
{
struct pci_dev *dev = to_pci_dev(ap->host->dev);
u8 master_port = ap->port_no ? 0x42 : 0x40;
u16 master_data;
u8 speed = adev->dma_mode;
int devid = adev->devno + 2 * ap->port_no;
unsigned long flags;
u8 udma_enable;
static const /* ISP RTC */
u8 timings[][2] = { { 0, 0 },
{ 0, 0 },
{ 1, 0 },
{ 2, 1 },
{ 2, 3 }, };
spin_lock_irqsave(&efar_lock, flags);
pci_read_config_word(dev, master_port, &master_data);
pci_read_config_byte(dev, 0x48, &udma_enable);
if (speed >= XFER_UDMA_0) {
unsigned int udma = adev->dma_mode - XFER_UDMA_0;
u16 udma_timing;
udma_enable |= (1 << devid);
/* Load the UDMA mode number */
pci_read_config_word(dev, 0x4A, &udma_timing);
udma_timing &= ~(7 << (4 * devid));
udma_timing |= udma << (4 * devid);
pci_write_config_word(dev, 0x4A, udma_timing);
} else {
/*
* MWDMA is driven by the PIO timings. We must also enable
* IORDY unconditionally along with TIME1. PPE has already
* been set when the PIO timing was set.
*/
unsigned int mwdma = adev->dma_mode - XFER_MW_DMA_0;
unsigned int control;
u8 slave_data;
const unsigned int needed_pio[3] = {
XFER_PIO_0, XFER_PIO_3, XFER_PIO_4
};
int pio = needed_pio[mwdma] - XFER_PIO_0;
control = 3; /* IORDY|TIME1 */
/* If the drive MWDMA is faster than it can do PIO then
we must force PIO into PIO0 */
if (adev->pio_mode < needed_pio[mwdma])
/* Enable DMA timing only */
control |= 8; /* PIO cycles in PIO0 */
if (adev->devno) { /* Slave */
master_data &= 0xFF4F; /* Mask out IORDY|TIME1|DMAONLY */
master_data |= control << 4;
pci_read_config_byte(dev, 0x44, &slave_data);
slave_data &= ap->port_no ? 0x0F : 0xF0;
/* Load the matching timing */
slave_data |= ((timings[pio][0] << 2) | timings[pio][1]) << (ap->port_no ? 4 : 0);
pci_write_config_byte(dev, 0x44, slave_data);
} else { /* Master */
master_data &= 0xCCF4; /* Mask out IORDY|TIME1|DMAONLY
and master timing bits */
master_data |= control;
master_data |=
(timings[pio][0] << 12) |
(timings[pio][1] << 8);
}
udma_enable &= ~(1 << devid);
pci_write_config_word(dev, master_port, master_data);
}
pci_write_config_byte(dev, 0x48, udma_enable);
spin_unlock_irqrestore(&efar_lock, flags);
}
static struct scsi_host_template efar_sht = {
ATA_BMDMA_SHT(DRV_NAME),
};
static struct ata_port_operations efar_ops = {
.inherits = &ata_bmdma_port_ops,
.cable_detect = efar_cable_detect,
.set_piomode = efar_set_piomode,
.set_dmamode = efar_set_dmamode,
.prereset = efar_pre_reset,
};
/**
* efar_init_one - Register EFAR ATA PCI device with kernel services
* @pdev: PCI device to register
* @ent: Entry in efar_pci_tbl matching with @pdev
*
* Called from kernel PCI layer.
*
* LOCKING:
* Inherited from PCI layer (may sleep).
*
* RETURNS:
* Zero on success, or -ERRNO value.
*/
static int efar_init_one (struct pci_dev *pdev, const struct pci_device_id *ent)
{
static int printed_version;
static const struct ata_port_info info = {
.flags = ATA_FLAG_SLAVE_POSS,
.pio_mask = ATA_PIO4,
.mwdma_mask = ATA_MWDMA12_ONLY,
.udma_mask = ATA_UDMA4,
.port_ops = &efar_ops,
};
const struct ata_port_info *ppi[] = { &info, &info };
if (!printed_version++)
dev_printk(KERN_DEBUG, &pdev->dev,
"version " DRV_VERSION "\n");
return ata_pci_sff_init_one(pdev, ppi, &efar_sht, NULL, 0);
}
static const struct pci_device_id efar_pci_tbl[] = {
{ PCI_VDEVICE(EFAR, 0x9130), },
{ } /* terminate list */
};
static struct pci_driver efar_pci_driver = {
.name = DRV_NAME,
.id_table = efar_pci_tbl,
.probe = efar_init_one,
.remove = ata_pci_remove_one,
#ifdef CONFIG_PM
.suspend = ata_pci_device_suspend,
.resume = ata_pci_device_resume,
#endif
};
static int __init efar_init(void)
{
return pci_register_driver(&efar_pci_driver);
}
static void __exit efar_exit(void)
{
pci_unregister_driver(&efar_pci_driver);
}
module_init(efar_init);
module_exit(efar_exit);
MODULE_AUTHOR("Alan Cox");
MODULE_DESCRIPTION("SCSI low-level driver for EFAR PIIX clones");
MODULE_LICENSE("GPL");
MODULE_DEVICE_TABLE(pci, efar_pci_tbl);
MODULE_VERSION(DRV_VERSION);