Re: CF flash PATA on libata failure to attach

[Mark Lord <liml@rtr.ca>]

Andrew Hall wrote:
>
> Yes!! It worked.. which means you were right - forcing the channel to PIO4
> and the drive was happy. The problem I have now is that we do in fact also
> have a SATA HDD connected to the same controller used for database and
> logging data - this now also is forced to use PIO4. How can I force the
> first channel to only use PIO and the remainder to use MWDMA2? 
> 
> Thanks for your help..

You're welcome.

Here's a slightly modified hack, which should leave your SATA
drive working as well as the CF card.

Tejun / Alan : do we really want to continue attempting mdma2
on a modern chipset such as ICH8 ???

The best mdma2 can do is the same throughput as pio4,
and the bus occupancy is so high for mdma2 that it really
probably isn't worthwhile -- only CF cards seem to use it
in modern systems anyway.

Signed-off-by:  Mark Lord <mlord@pobox.com>
---
--- linux/drivers/ata/ata_piix.c.orig	2007-06-10 18:58:27.000000000 -0400
+++ linux/drivers/ata/ata_piix.c	2007-06-28 21:09:04.000000000 -0400
@@ -537,7 +537,7 @@
 		.flags		= PIIX_SATA_FLAGS | PIIX_FLAG_SCR |
 				  PIIX_FLAG_AHCI,
 		.pio_mask	= 0x1f,	/* pio0-4 */
-		.mwdma_mask	= 0x07, /* mwdma0-2 */
+		.mwdma_mask	= 0x00, /* mwdma0-2 */
 		.udma_mask	= 0x7f,	/* udma0-6 */
 		.port_ops	= &piix_sata_ops,
 	},