From: Bhavna Sarathy <bnagendr@redhat.com>
Date: Thu, 9 Jul 2009 11:45:00 -0400
Subject: [x86] fix suspend/resume issue on SB800 chipset
Message-id: 20090709154633.9518.50596.sendpatchset@localhost.localdomain
O-Subject: [RHEL5.4 PATCH] Fix suspend/resume issue on SB800 chipset
Bugzilla: 498135
RH-Acked-by: Prarit Bhargava <prarit@redhat.com>
RH-Acked-by: Matthew Garrett <mjg@redhat.com>
RH-Acked-by: Stefan Assmann <sassmann@redhat.com>
RH-Acked-by: Andy Gospodarek <gospo@redhat.com>

Resolves BZ 498135.

This patch fixes an SB800 chipset bug related to suspend/resume.  Rebooting after
suspending to ram/disk causes the Sb800 system to hang in the reboot process.
This patch fixes paranoia about using BIOS quickboot mechanism.

Testing:
SB800 Croaker system: i386, and x86_64 pass
Sb800 Tarpon system: i386, and x86_64 pass
SB700 Shiner system: regression testing no issues found
nVidia MCP61: i386 and x86_64 no issues
Intel ICH9: no regressions due to SB800 patch found

Upstream git commit:
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=63d38198a0f57dca87e6cb79931c7bedbb7ab069

Brew build:
https://brewweb.devel.redhat.com/taskinfo?taskID=1879095

Please review and provide ACK for RHEL5.4.

Bhavna

diff --git a/arch/i386/kernel/smpboot.c b/arch/i386/kernel/smpboot.c
index 86fd346..adf9295 100644
--- a/arch/i386/kernel/smpboot.c
+++ b/arch/i386/kernel/smpboot.c
@@ -1019,6 +1019,11 @@ static int __cpuinit do_boot_cpu(int apicid, int cpu)
 	/* mark "stuck" area as not stuck */
 	*((volatile unsigned long *)trampoline_base) = 0;
 
+	/*
+	 * Cleanup possible dangling ends...
+	 */
+	smpboot_restore_warm_reset_vector();
+
 	return boot_error;
 }
 
@@ -1259,11 +1264,6 @@ static void __init smp_boot_cpus(unsigned int max_cpus)
 	}
 
 	/*
-	 * Cleanup possible dangling ends...
-	 */
-	smpboot_restore_warm_reset_vector();
-
-	/*
 	 * Allow the user to impress friends.
 	 */
 	Dprintk("Before bogomips.\n");
diff --git a/arch/x86_64/kernel/smpboot.c b/arch/x86_64/kernel/smpboot.c
index 568a378..7c6ced7 100644
--- a/arch/x86_64/kernel/smpboot.c
+++ b/arch/x86_64/kernel/smpboot.c
@@ -927,6 +927,19 @@ do_rest:
 		return -EIO;
 	}
 
+	/*
+	 * Install writable page 0 entry to set BIOS data area.
+	 */
+	local_flush_tlb();
+
+	/*
+	 * Paranoid:  Set warm reset code and vector here back
+	 * to default values.
+	 */
+	CMOS_WRITE(0, 0xf);
+
+	*((volatile long *) phys_to_virt(0x467)) = 0;
+
 	return 0;
 }