[PATCH] sata_nv ADMA/NCQ support for nForce4

This patch adds support for ADMA mode on NVIDIA nForce4 (CK804/MCP04) SATA
controllers to the sata_nv driver.  Benefits of ADMA mode include:

- NCQ support

- Reduced CPU overhead (controller DMAs command information from memory
  instead of them being pushed in by the CPU)

- Full 64-bit DMA support

ADMA mode is enabled by default in this version.  To disable it, set the
module parameter adma_enabled=0.

Signed-off-by: Robert Hancock <hancockr@shaw.ca>
Cc: Jeff Garzik <jeff@garzik.org>
Cc: Tejun Heo <htejun@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/ata/libata-sff.c

@@ -732,7 +732,7 @@ void ata_bmdma_drive_eh(struct ata_port *ap, ata_prereset_fn_t prereset,
 		   qc->tf.protocol == ATA_PROT_ATAPI_DMA)) {
 		u8 host_stat;
 
-		host_stat = ata_bmdma_status(ap);
+		host_stat = ap->ops->bmdma_status(ap);
 
 		ata_ehi_push_desc(&ehc->i, "BMDMA stat 0x%x", host_stat);