pata_it821x: (partially) fix DMA in RAID mode

Code intended to check DMA status was checking DMA command register.

Moreover firmware seems to "forget" to set DMA capable bit for the
slave device (at least in RAID mode but without ITE RAID volumes) so
check device ID for DMA capable bit when deciding whether to use DMA
and remove DMA status check completely.

Thanks to Pavol Simo for the bugreport and testing the initial fix.

This change unfortunately still doesn't fix DMA in RAID mode (which
works fine with IDE it821x) but Alan is working on the missing pieces
(pata_it821x vs libata EH issues).

Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Acked-by: Alan Cox <alan@redhat.com>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
This commit is contained in:
Bartlomiej Zolnierkiewicz 2007-06-11 11:40:07 +02:00 committed by Jeff Garzik
parent 9f7897554e
commit 374abf2cb1

View File

@ -2,6 +2,7 @@
* pata_it821x.c - IT821x PATA for new ATA layer
* (C) 2005 Red Hat Inc
* Alan Cox <alan@redhat.com>
* (C) 2007 Bartlomiej Zolnierkiewicz
*
* based upon
*
@ -79,7 +80,7 @@
#define DRV_NAME "pata_it821x"
#define DRV_VERSION "0.3.6"
#define DRV_VERSION "0.3.7"
struct it821x_dev
{
@ -460,14 +461,8 @@ static unsigned int it821x_passthru_qc_issue_prot(struct ata_queued_cmd *qc)
static int it821x_smart_set_mode(struct ata_port *ap, struct ata_device **unused)
{
int dma_enabled = 0;
int i;
/* Bits 5 and 6 indicate if DMA is active on master/slave */
/* It is possible that BMDMA isn't allocated */
if (ap->ioaddr.bmdma_addr)
dma_enabled = ioread8(ap->ioaddr.bmdma_addr + ATA_DMA_CMD);
for (i = 0; i < ATA_MAX_DEVICES; i++) {
struct ata_device *dev = &ap->device[i];
if (ata_dev_enabled(dev)) {
@ -476,7 +471,7 @@ static int it821x_smart_set_mode(struct ata_port *ap, struct ata_device **unused
dev->dma_mode = XFER_MW_DMA_0;
/* We do need the right mode information for DMA or PIO
and this comes from the current configuration flags */
if (dma_enabled & (1 << (5 + i))) {
if (ata_id_has_dma(dev->id)) {
ata_dev_printk(dev, KERN_INFO, "configured for DMA\n");
dev->xfer_mode = XFER_MW_DMA_0;
dev->xfer_shift = ATA_SHIFT_MWDMA;