From: Prarit Bhargava <prarit@redhat.com>
Date: Thu, 6 Nov 2008 14:48:12 -0500
Subject: [acpi] always use 32 bit value for GPE0 on HP xw boxes
Message-id: 20081106194812.24223.9983.sendpatchset@prarit.bos.redhat.com
O-Subject: [RHEL5.3 PATCH] HP xw BIOS WAR -- always used 32 bit value for GPE0
Bugzilla: 456638
RH-Acked-by: Brian Maly <bmaly@redhat.com>
RH-Acked-by: Matthew Garrett <mjg@redhat.com>
RH-Acked-by: Neil Horman <nhorman@redhat.com>

Don,

Sorry for the late-breaking patch.  jburke recently saw this occur on a bare-
metal boot so I'm submitting the patch for inclusion to RHEL5.3.  I've had
this "in-the-can" for a few weeks but was hoping that HP would get around to
fixing the BIOS...

P.
------------------

HP xw BIOSes contain a little bug which appears effect kdump although we
have recently seen this on bare-metal.

On boot the console log contains:

ACPI Error (evgpe-0711): No handler or method for GPE[ 0], disabling event
[20060707]
ACPI Error (evgpe-0711): No handler or method for GPE[ 1], disabling event
[20060707]
ACPI Error (evgpe-0711): No handler or method for GPE[ 2], disabling event
[20060707]
ACPI Error (evgpe-0711): No handler or method for GPE[ 5], disabling event
[20060707]
ACPI Error (evgpe-0711): No handler or method for GPE[ 6], disabling event
[20060707]
ACPI Error (evgpe-0711): No handler or method for GPE[ 7], disabling event
[20060707]
ACPI Error (evgpe-0711): No handler or method for GPE[ A], disabling event
[20060707]

This is caused by a bug in the FADT table where the 64-bit address for GPE
is incorrect.  However, the 32-bit value is correct.

The ACPI specification indicates that the 64-bit value is to be used in
favor of the 32-bit value.  On these HP xw systems, however, the opposite must
be done.

This patch is a WAR for the broken BIOS/ACPI tables in the HP xw systems.

Sucessfully compiled and tested by me.

Resolves BZ 456638.

diff --git a/drivers/acpi/events/evgpeblk.c b/drivers/acpi/events/evgpeblk.c
index 95ddeb4..a5093f3 100644
--- a/drivers/acpi/events/evgpeblk.c
+++ b/drivers/acpi/events/evgpeblk.c
@@ -41,6 +41,7 @@
  * POSSIBILITY OF SUCH DAMAGES.
  */
 
+#include <linux/dmi.h>
 #include <acpi/acpi.h>
 #include <acpi/acevents.h>
 #include <acpi/acnamesp.h>
@@ -1058,6 +1059,56 @@ acpi_ev_initialize_gpe_block(struct acpi_namespace_node *gpe_device,
 	return_ACPI_STATUS(status);
 }
 
+static int hp_gpe_use_32_bit(struct dmi_system_id *d)
+{
+	if ((u64)acpi_gbl_FADT->V1_gpe0_blk !=
+	    acpi_gbl_FADT->xgpe0_blk.address) {
+		printk("HP xw System ... overriding gpe0_blk to "
+		       "32-bit value \n");
+		acpi_gbl_FADT->xgpe0_blk.address =
+						(u64)acpi_gbl_FADT->V1_gpe0_blk;
+	}
+
+	return 0;
+}
+
+/* HP xw series blacklist */
+static struct dmi_system_id acpi_hp_gpe_table[] = {
+	{
+	 .callback = hp_gpe_use_32_bit,
+	 .ident = "HP xw 4600",
+	 .matches = {
+		     DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
+		     DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4600 Workstation"),
+	 	    },
+	},
+	{
+	 .callback = hp_gpe_use_32_bit,
+	 .ident = "HP xw 4800",
+	 .matches = {
+		     DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
+		     DMI_MATCH(DMI_PRODUCT_NAME, "HP xw4800 Workstation"),
+	 	    },
+	},
+	{
+	 .callback = hp_gpe_use_32_bit,
+	 .ident = "HP xw 8600",
+	 .matches = {
+		     DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
+		     DMI_MATCH(DMI_PRODUCT_NAME, "HP xw8600 Workstation"),
+	 	    },
+	},
+	{
+	 .callback = hp_gpe_use_32_bit,
+	 .ident = "HP xw 9400",
+	 .matches = {
+		     DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
+		     DMI_MATCH(DMI_PRODUCT_NAME, "HP xw9400 Workstation"),
+	 	    },
+	},
+	 {}
+};
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ev_gpe_initialize
@@ -1100,6 +1151,11 @@ acpi_status acpi_ev_gpe_initialize(void)
 	 *  to be the same size."
 	 */
 
+	/* This is strictly against the ACPI spec.  We should always use the
+	   64-bit address.  However, on HP xw systems it appears that the
+	   64-bit address is incorrect so use the 32-bit address */
+	dmi_check_system(acpi_hp_gpe_table);
+
 	/*
 	 * Determine the maximum GPE number for this machine.
 	 *