From: David Milburn <dmilburn@redhat.com>
Date: Fri, 20 Feb 2009 14:28:16 -0600
Subject: [sata] libata: ahci withdraw IGN_SERR_INTERNAL for SB800
Message-id: 20090220202816.GA5849@dhcp-210.hsv.redhat.com
O-Subject: [RHEL5.4 PATCH] libata: ahci withdraw IGN_SERR_INTERNAL for SB800
Bugzilla: 474301
RH-Acked-by: Jeff Garzik <jgarzik@redhat.com>
RH-Acked-by: Mikulas Patocka <mpatocka@redhat.com>
RH-Acked-by: Prarit Bhargava <prarit@redhat.com>

This patch is from Shane Huang (AMD) and it resolves
BZ 474301. The work-around to ignore false host internal
errors leading to many sata error messages is only needed
on SB600/SB700 and should be removed for SB800. Similiar
code was applied to RHEL4 (.81.EL) and this patch is a
backport of the following upstream commit. AMD has verified on
SB700 and SB800 platform running 2.6.18-131.el5 test kernel
built with this patch.

Please review and ACK.

Thanks,
David

commit e427fe042cf90c0652eed9a85e57a8fd8af89890
Author: Shane Huang <shane.huang@amd.com>
Date:   Tue Dec 30 10:53:41 2008 +0800

    [libata] ahci: Withdraw IGN_SERR_INTERNAL for SB800 SATA

    There is an issue in ATI SB600/SB700 SATA that PxSERR.E should not be
    set on some conditions, which will lead to many SATA ODD error messages.
    commit 55a61604cd1354e1783364e1c901034f2f474b7d is the workaround.
    Since SB800 fixed this HW issue, IGN_SERR_INTERNAL should be withdrawn
    for SB800.

 drivers/ata/ahci.c |    8 ++++++--
 1 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/ata/ahci.c b/drivers/ata/ahci.c
index f200f3e..fb31aa3 100644
--- a/drivers/ata/ahci.c
+++ b/drivers/ata/ahci.c
@@ -105,7 +105,7 @@ enum {
 	board_ahci_ign_iferr	= 2,
 	board_ahci_sb600	= 3,
 	board_ahci_mv		= 4,
-	board_ahci_sb700	= 5,
+	board_ahci_sb700	= 5, /* for SB700 and SB800 */
 
 	/* global controller registers */
 	HOST_CAP		= 0x00, /* host capabilities */
@@ -435,7 +435,7 @@ static const struct ata_port_info ahci_port_info[] = {
 		.udma_mask	= ATA_UDMA6,
 		.port_ops	= &ahci_ops,
 	},
-	/* board_ahci_sb700 */
+	/* board_ahci_sb700, for SB700 and SB800 */
 	{
 		AHCI_HFLAGS	(AHCI_HFLAG_IGN_SERR_INTERNAL),
 		.flags		= AHCI_FLAG_COMMON,
@@ -2573,6 +2573,10 @@ static int ahci_init_one(struct pci_dev *pdev, const struct pci_device_id *ent)
 		return -ENOMEM;
 	hpriv->flags |= (unsigned long)pi.private_data;
 
+	/* SB800 does NOT need the workaround to ignore SERR_INTERNAL */
+	if (ent->driver_data == board_ahci_sb700 && pdev->revision >= 0x40)
+		hpriv->flags &= ~AHCI_HFLAG_IGN_SERR_INTERNAL;
+
 	if ((hpriv->flags & AHCI_HFLAG_NO_MSI) || pci_enable_msi(pdev))
 		pci_intx(pdev, 1);