[patch 071/100] pata_hpt37x: fix HPT370 DMA timeouts

Chris Wright
2009-04-23T07:53:19Z

[-- Attachment #1: pata_hpt37x-fix-hpt370-dma-timeouts.patch --]
[-- Type: text/plain, Size: 2168 bytes --]

-stable review patch. If anyone has any objections, please let us know.
---------------------

From: Sergei Shtylyov <sshtylyov@ru.mvista.com>

upstream commit: 265b7215aed36941620b65ecfff516200fb190c1

The libata driver has copied the code from the IDE driver which caused a post
2.4.18 regression on many HPT370[A] chips -- DMA stopped to work completely,
only causing timeouts. Now remove hpt370_bmdma_start() for good...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
---
drivers/ata/pata_hpt37x.c | 22 ++--------------------
1 file changed, 2 insertions(+), 20 deletions(-)

--- a/drivers/ata/pata_hpt37x.c
+++ b/drivers/ata/pata_hpt37x.c
@@ -8,7 +8,7 @@
* Copyright (C) 1999-2003 Andre Hedrick <andre@linux-ide.org>
* Portions Copyright (C) 2001 Sun Microsystems, Inc.
* Portions Copyright (C) 2003 Red Hat Inc
- * Portions Copyright (C) 2005-2007 MontaVista Software, Inc.
+ * Portions Copyright (C) 2005-2009 MontaVista Software, Inc.
*
* TODO
* Look into engine reset on timeout errors. Should not be required.
@@ -24,7 +24,7 @@
#include <linux/libata.h>

#define DRV_NAME "pata_hpt37x"
-#define DRV_VERSION "0.6.11"
+#define DRV_VERSION "0.6.12"

struct hpt_clock {
u8 xfer_speed;
@@ -445,23 +445,6 @@ static void hpt370_set_dmamode(struct at
}

/**
- * hpt370_bmdma_start - DMA engine begin
- * @qc: ATA command
- *
- * The 370 and 370A want us to reset the DMA engine each time we
- * use it. The 372 and later are fine.
- */
-
-static void hpt370_bmdma_start(struct ata_queued_cmd *qc)
-{
- struct ata_port *ap = qc->ap;
- struct pci_dev *pdev = to_pci_dev(ap->host->dev);
- pci_write_config_byte(pdev, 0x50 + 4 * ap->port_no, 0x37);
- udelay(10);
- ata_bmdma_start(qc);
-}
-
-/**
* hpt370_bmdma_end - DMA engine stop
* @qc: ATA command
*
@@ -598,7 +581,6 @@ static struct scsi_host_template hpt37x_
static struct ata_port_operations hpt370_port_ops = {
.inherits = &ata_bmdma_port_ops,

- .bmdma_start = hpt370_bmdma_start,
.bmdma_stop = hpt370_bmdma_stop,

.mode_filter = hpt370_filter,