Commit 44854add authored by Sergei Shtylyov's avatar Sergei Shtylyov Committed by Linus Torvalds

[PATCH] PIIX/SLC90E66: PIO mode fallback fix

The fallback to PIO mode in the hwif->dma_check() handler doesn't work in
the Intel PIIX and SMsC SLC90E66 IDE drivers because:

- config_drive_for_dma() calls the hwif->speedproc() handler with a wrong
  mode number (unbiased by XFER_PIO_0) in case of the PIO fallback;

- hwif->tuneproc() handler doesn't really set the drive's own speed (this
  is not fixed as yet).
Signed-off-by: default avatarSergei Shtylyov <sshtylyov@ru.mvista.com>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Acked-by: default avatarBartlomiej Zolnierkiewicz <B.Zolnierkiewicz@elka.pw.edu.pl>
Signed-off-by: default avatarAndrew Morton <akpm@osdl.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@osdl.org>
parent 242ce41f
/*
* linux/drivers/ide/pci/piix.c Version 0.44 March 20, 2003
* linux/drivers/ide/pci/piix.c Version 0.45 May 12, 2006
*
* 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>
* Copyright (C) 2006 MontaVista Software, Inc. <source@mvista.com>
*
* May be copied or modified under the terms of the GNU General Public License
*
* PIO mode setting function for Intel chipsets.
* PIO mode setting function for Intel chipsets.
* For use instead of BIOS settings.
*
* 40-41
......@@ -25,7 +26,7 @@
* sitre = word42 & 0x4000; secondary
*
* 44 8421|8421 hdd|hdb
*
*
* 48 8421 hdd|hdc|hdb|hda udma enabled
*
* 0001 hda
......@@ -357,21 +358,20 @@ static int piix_tune_chipset (ide_drive_t *drive, u8 xferspeed)
* @drive: IDE drive to configure
*
* Set up a PIIX interface channel for the best available speed.
* We prefer UDMA if it is available and then MWDMA. If DMA is
* not available we switch to PIO and return 0.
* We prefer UDMA if it is available and then MWDMA. If DMA is
* not available we switch to PIO and return 0.
*/
static int piix_config_drive_for_dma (ide_drive_t *drive)
{
u8 speed = ide_dma_speed(drive, piix_ratemask(drive));
/* If no DMA speed was available or the chipset has DMA bugs
then disable DMA and use PIO */
if (!speed || no_piix_dma) {
u8 tspeed = ide_get_best_pio_mode(drive, 255, 5, NULL);
speed = piix_dma_2_pio(XFER_PIO_0 + tspeed);
}
/*
* If no DMA speed was available or the chipset has DMA bugs
* then disable DMA and use PIO
*/
if (!speed || no_piix_dma)
return 0;
(void) piix_tune_chipset(drive, speed);
return ide_dma_enable(drive);
......@@ -394,17 +394,16 @@ static int piix_config_drive_xfer_rate (ide_drive_t *drive)
if ((id->capability & 1) && drive->autodma) {
if (ide_use_dma(drive)) {
if (piix_config_drive_for_dma(drive))
return hwif->ide_dma_on(drive);
}
if (ide_use_dma(drive) && piix_config_drive_for_dma(drive))
return hwif->ide_dma_on(drive);
goto fast_ata_pio;
} else if ((id->capability & 8) || (id->field_valid & 2)) {
fast_ata_pio:
/* Find best PIO mode. */
hwif->tuneproc(drive, 255);
(void) hwif->speedproc(drive, XFER_PIO_0 +
ide_get_best_pio_mode(drive, 255, 4, NULL));
return hwif->ide_dma_off_quietly(drive);
}
/* IORDY not supported */
......
/*
* linux/drivers/ide/pci/slc90e66.c Version 0.11 September 11, 2002
* linux/drivers/ide/pci/slc90e66.c Version 0.12 May 12, 2006
*
* Copyright (C) 2000-2002 Andre Hedrick <andre@linux-ide.org>
* Copyright (C) 2006 MontaVista Software, Inc. <source@mvista.com>
*
* This a look-a-like variation of the ICH0 PIIX4 Ultra-66,
* This is a look-alike variation of the ICH0 PIIX4 Ultra-66,
* but this keeps the ISA-Bridge and slots alive.
*
*/
......@@ -158,10 +159,8 @@ static int slc90e66_config_drive_for_dma (ide_drive_t *drive)
{
u8 speed = ide_dma_speed(drive, slc90e66_ratemask(drive));
if (!(speed)) {
u8 tspeed = ide_get_best_pio_mode(drive, 255, 5, NULL);
speed = slc90e66_dma_2_pio(XFER_PIO_0 + tspeed);
}
if (!speed)
return 0;
(void) slc90e66_tune_chipset(drive, speed);
return ide_dma_enable(drive);
......@@ -176,16 +175,15 @@ static int slc90e66_config_drive_xfer_rate (ide_drive_t *drive)
if (id && (id->capability & 1) && drive->autodma) {
if (ide_use_dma(drive)) {
if (slc90e66_config_drive_for_dma(drive))
return hwif->ide_dma_on(drive);
}
if (ide_use_dma(drive) && slc90e66_config_drive_for_dma(drive))
return hwif->ide_dma_on(drive);
goto fast_ata_pio;
} else if ((id->capability & 8) || (id->field_valid & 2)) {
fast_ata_pio:
hwif->tuneproc(drive, 5);
(void) hwif->speedproc(drive, XFER_PIO_0 +
ide_get_best_pio_mode(drive, 255, 4, NULL));
return hwif->ide_dma_off_quietly(drive);
}
/* IORDY not supported */
......
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