Re: PATA failure with piix, works with libata

From: Jeff Garzik
Date: Sun Mar 05 2006 - 20:04:47 EST


Matthew Garrett wrote:
On Sun, Mar 05, 2006 at 07:58:09PM -0500, Jeff Garzik wrote:

Matthew Garrett wrote:

Yeah, this is an ICH7. I can't find anything in drivers/ide that would result in it being done, which is why I'm kind of confused. ide_ack_intr seems to be defined to do nothing on x86 since IDE_ARCH_ACK_INTR isn't defined there?

This is more a piix-specific behavior than an arch-specific behavior.


Joy. So it works by accident in legacy mode? Does anything need to be done other than just writing the DMA status register back? I'm not finding anything terribly helpful in the ICH7 docs, but I may just be being blind.

Honestly I'm quite surprised that there is a difference between legacy and native mode (more joy :)). ICH seems to want an ack to the bmdma status register even on non-DMA commands, since it directly reflects the IDE INTRQ line. Perhaps pounding on the Status register will clear that condition, thus enabling legacy software to continue successfully without worry about this ICH-specific detail. </speculation>

Jeff


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