Albert Lee wrote:
patch 2/2 (revised):
- Do the dma status clearing in ide_intr() and add a new 
hwif->ide_dma_clear_irq such that LLDD can override it.
- Fix drive->waiting_for_dma to work with CDB-intr devices.

Signed-off-by: Albert Lee <[EMAIL PROTECTED]>
---
hwif->dma is not reliable: ide_intr() races with dma_start(). Sometimes we got 
hwif->dma == 0
in ide_intr() even though it is actually a DMA interrupt. So, 
drive->waiting_for_dma is used instead.

Also revised per Sergei's comments and let ide_dma_clear_irq return "void".
The "if (hwif->dma_status)" check in __ide_dma_clear_irq() is kept as is since 
I think
it would be safer for the old ISA/VESA IDE devices that has no BMDMA registers.

ISA/VESA drivers shouldn't have this method defined at all since they're PIO only. But well, it won't hurt...

For your review, thanks.

diff -Nrup 01_remove_from_ide_cd/drivers/ide/ide-cd.c 
02_add_to_ide_intr/drivers/ide/ide-cd.c
--- 01_remove_from_ide_cd/drivers/ide/ide-cd.c  2007-01-24 11:00:03.000000000 
+0800
+++ 02_add_to_ide_intr/drivers/ide/ide-cd.c     2007-01-25 16:52:20.000000000 
+0800
@@ -923,6 +923,10 @@ static ide_startstop_t cdrom_start_packe
                HWIF(drive)->OUTB(drive->ctl, IDE_CONTROL_REG);
if (CDROM_CONFIG_FLAGS (drive)->drq_interrupt) {
+               /* waiting for CDB interrupt, not DMA yet. */
+               if (info->dma)
+                       drive->waiting_for_dma = 0;
+
                /* packet command */
                ide_execute_command(drive, WIN_PACKETCMD, handler, 
ATAPI_WAIT_PC, cdrom_timer_expiry);
                return ide_started;
@@ -965,6 +969,10 @@ static ide_startstop_t cdrom_transfer_pa
                /* Check for errors. */
                if (cdrom_decode_status(drive, DRQ_STAT, NULL))
                        return ide_stopped;
+
+               /* Ok, next interrupt will be dma interrupt. */
+               if (info->dma)
+                       drive->waiting_for_dma = 1;
        } else {
                /* Otherwise, we must wait for DRQ to get set. */
                if (ide_wait_stat(&startstop, drive, DRQ_STAT,

   Erm... shouldn't we set drive->waiting_for_dma in hwif->dma_start() then?
Why it's set in hwif->dma_setup() at all I wonder?

MBR, Sergei
-
To unsubscribe from this list: send the line "unsubscribe linux-ide" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html

Reply via email to