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linux/drivers/ide/ide-xfer-mode.c
Bartlomiej Zolnierkiewicz 5880b5de71 ide: don't enable IORDY at a probe time
* Add 'unsigned long port_flags' field to ide_hwif_t.

* Add IDE_PFLAG_PROBING port flag and keep it set during probing.

* Fix ide_pio_need_iordy() to not enable IORDY at a probe time
  (IORDY may lead to controller lock up on certain controllers
   if the port is not occupied).

Loosely based on the recent libata's fix by Tejun, thanks to Alan
for the hint that IDE may also need it.

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
2009-06-15 18:52:54 +02:00

262 lines
6.6 KiB
C

#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/ide.h>
#include <linux/bitops.h>
static const char *udma_str[] =
{ "UDMA/16", "UDMA/25", "UDMA/33", "UDMA/44",
"UDMA/66", "UDMA/100", "UDMA/133", "UDMA7" };
static const char *mwdma_str[] =
{ "MWDMA0", "MWDMA1", "MWDMA2", "MWDMA3", "MWDMA4" };
static const char *swdma_str[] =
{ "SWDMA0", "SWDMA1", "SWDMA2" };
static const char *pio_str[] =
{ "PIO0", "PIO1", "PIO2", "PIO3", "PIO4", "PIO5", "PIO6" };
/**
* ide_xfer_verbose - return IDE mode names
* @mode: transfer mode
*
* Returns a constant string giving the name of the mode
* requested.
*/
const char *ide_xfer_verbose(u8 mode)
{
const char *s;
u8 i = mode & 0xf;
if (mode >= XFER_UDMA_0 && mode <= XFER_UDMA_7)
s = udma_str[i];
else if (mode >= XFER_MW_DMA_0 && mode <= XFER_MW_DMA_4)
s = mwdma_str[i];
else if (mode >= XFER_SW_DMA_0 && mode <= XFER_SW_DMA_2)
s = swdma_str[i];
else if (mode >= XFER_PIO_0 && mode <= XFER_PIO_6)
s = pio_str[i & 0x7];
else if (mode == XFER_PIO_SLOW)
s = "PIO SLOW";
else
s = "XFER ERROR";
return s;
}
EXPORT_SYMBOL(ide_xfer_verbose);
/**
* ide_get_best_pio_mode - get PIO mode from drive
* @drive: drive to consider
* @mode_wanted: preferred mode
* @max_mode: highest allowed mode
*
* This routine returns the recommended PIO settings for a given drive,
* based on the drive->id information and the ide_pio_blacklist[].
*
* Drive PIO mode is auto-selected if 255 is passed as mode_wanted.
* This is used by most chipset support modules when "auto-tuning".
*/
u8 ide_get_best_pio_mode(ide_drive_t *drive, u8 mode_wanted, u8 max_mode)
{
u16 *id = drive->id;
int pio_mode = -1, overridden = 0;
if (mode_wanted != 255)
return min_t(u8, mode_wanted, max_mode);
if ((drive->hwif->host_flags & IDE_HFLAG_PIO_NO_BLACKLIST) == 0)
pio_mode = ide_scan_pio_blacklist((char *)&id[ATA_ID_PROD]);
if (pio_mode != -1) {
printk(KERN_INFO "%s: is on PIO blacklist\n", drive->name);
} else {
pio_mode = id[ATA_ID_OLD_PIO_MODES] >> 8;
if (pio_mode > 2) { /* 2 is maximum allowed tPIO value */
pio_mode = 2;
overridden = 1;
}
if (id[ATA_ID_FIELD_VALID] & 2) { /* ATA2? */
if (ata_id_is_cfa(id) && (id[ATA_ID_CFA_MODES] & 7))
pio_mode = 4 + min_t(int, 2,
id[ATA_ID_CFA_MODES] & 7);
else if (ata_id_has_iordy(id)) {
if (id[ATA_ID_PIO_MODES] & 7) {
overridden = 0;
if (id[ATA_ID_PIO_MODES] & 4)
pio_mode = 5;
else if (id[ATA_ID_PIO_MODES] & 2)
pio_mode = 4;
else
pio_mode = 3;
}
}
}
if (overridden)
printk(KERN_INFO "%s: tPIO > 2, assuming tPIO = 2\n",
drive->name);
}
if (pio_mode > max_mode)
pio_mode = max_mode;
return pio_mode;
}
EXPORT_SYMBOL_GPL(ide_get_best_pio_mode);
int ide_pio_need_iordy(ide_drive_t *drive, const u8 pio)
{
/*
* IORDY may lead to controller lock up on certain controllers
* if the port is not occupied.
*/
if (pio == 0 && (drive->hwif->port_flags & IDE_PFLAG_PROBING))
return 0;
return ata_id_pio_need_iordy(drive->id, pio);
}
EXPORT_SYMBOL_GPL(ide_pio_need_iordy);
int ide_set_pio_mode(ide_drive_t *drive, const u8 mode)
{
ide_hwif_t *hwif = drive->hwif;
const struct ide_port_ops *port_ops = hwif->port_ops;
if (hwif->host_flags & IDE_HFLAG_NO_SET_MODE)
return 0;
if (port_ops == NULL || port_ops->set_pio_mode == NULL)
return -1;
/*
* TODO: temporary hack for some legacy host drivers that didn't
* set transfer mode on the device in ->set_pio_mode method...
*/
if (port_ops->set_dma_mode == NULL) {
port_ops->set_pio_mode(drive, mode - XFER_PIO_0);
return 0;
}
if (hwif->host_flags & IDE_HFLAG_POST_SET_MODE) {
if (ide_config_drive_speed(drive, mode))
return -1;
port_ops->set_pio_mode(drive, mode - XFER_PIO_0);
return 0;
} else {
port_ops->set_pio_mode(drive, mode - XFER_PIO_0);
return ide_config_drive_speed(drive, mode);
}
}
int ide_set_dma_mode(ide_drive_t *drive, const u8 mode)
{
ide_hwif_t *hwif = drive->hwif;
const struct ide_port_ops *port_ops = hwif->port_ops;
if (hwif->host_flags & IDE_HFLAG_NO_SET_MODE)
return 0;
if (port_ops == NULL || port_ops->set_dma_mode == NULL)
return -1;
if (hwif->host_flags & IDE_HFLAG_POST_SET_MODE) {
if (ide_config_drive_speed(drive, mode))
return -1;
port_ops->set_dma_mode(drive, mode);
return 0;
} else {
port_ops->set_dma_mode(drive, mode);
return ide_config_drive_speed(drive, mode);
}
}
EXPORT_SYMBOL_GPL(ide_set_dma_mode);
/* req_pio == "255" for auto-tune */
void ide_set_pio(ide_drive_t *drive, u8 req_pio)
{
ide_hwif_t *hwif = drive->hwif;
const struct ide_port_ops *port_ops = hwif->port_ops;
u8 host_pio, pio;
if (port_ops == NULL || port_ops->set_pio_mode == NULL ||
(hwif->host_flags & IDE_HFLAG_NO_SET_MODE))
return;
BUG_ON(hwif->pio_mask == 0x00);
host_pio = fls(hwif->pio_mask) - 1;
pio = ide_get_best_pio_mode(drive, req_pio, host_pio);
/*
* TODO:
* - report device max PIO mode
* - check req_pio != 255 against device max PIO mode
*/
printk(KERN_DEBUG "%s: host max PIO%d wanted PIO%d%s selected PIO%d\n",
drive->name, host_pio, req_pio,
req_pio == 255 ? "(auto-tune)" : "", pio);
(void)ide_set_pio_mode(drive, XFER_PIO_0 + pio);
}
EXPORT_SYMBOL_GPL(ide_set_pio);
/**
* ide_rate_filter - filter transfer mode
* @drive: IDE device
* @speed: desired speed
*
* Given the available transfer modes this function returns
* the best available speed at or below the speed requested.
*
* TODO: check device PIO capabilities
*/
static u8 ide_rate_filter(ide_drive_t *drive, u8 speed)
{
ide_hwif_t *hwif = drive->hwif;
u8 mode = ide_find_dma_mode(drive, speed);
if (mode == 0) {
if (hwif->pio_mask)
mode = fls(hwif->pio_mask) - 1 + XFER_PIO_0;
else
mode = XFER_PIO_4;
}
/* printk("%s: mode 0x%02x, speed 0x%02x\n", __func__, mode, speed); */
return min(speed, mode);
}
/**
* ide_set_xfer_rate - set transfer rate
* @drive: drive to set
* @rate: speed to attempt to set
*
* General helper for setting the speed of an IDE device. This
* function knows about user enforced limits from the configuration
* which ->set_pio_mode/->set_dma_mode does not.
*/
int ide_set_xfer_rate(ide_drive_t *drive, u8 rate)
{
ide_hwif_t *hwif = drive->hwif;
const struct ide_port_ops *port_ops = hwif->port_ops;
if (port_ops == NULL || port_ops->set_dma_mode == NULL ||
(hwif->host_flags & IDE_HFLAG_NO_SET_MODE))
return -1;
rate = ide_rate_filter(drive, rate);
BUG_ON(rate < XFER_PIO_0);
if (rate >= XFER_PIO_0 && rate <= XFER_PIO_6)
return ide_set_pio_mode(drive, rate);
return ide_set_dma_mode(drive, rate);
}