[PATCH] x86_64: Support for AMD specific MCE Threshold.

MC4_MISC - DRAM Errors Threshold Register realized under AMD K8 Rev F.
This register is used to count correctable and uncorrectable ECC errors that occur during DRAM read operations.
The user may interface through sysfs files in order to change the threshold configuration.

bank%d/error_count - reads current error count, write to clear.
bank%d/interrupt_enable - set/clear interrupt enable.
bank%d/threshold_limit - read/write the threshold limit.

APIC vector 0xF9 in hw_irq.h.
5 software defined bank ids in mce.h.
new apic.c function to setup threshold apic lvt.
defaults to interrupt off, count enabled, and threshold limit max.
sysfs interface created on /sys/devices/system/threshold.

AK: added some ifdefs to make it compile on UP

Signed-off-by: Jacob Shin <jacob.shin@amd.com>
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/Kconfig b/arch/x86_64/Kconfig
index 21afa69..504dc52 100644
--- a/arch/x86_64/Kconfig
+++ b/arch/x86_64/Kconfig
@@ -374,6 +374,14 @@
 	   Additional support for intel specific MCE features such as
 	   the thermal monitor.
 
+config X86_MCE_AMD
+	bool "AMD MCE features"
+	depends on X86_MCE && X86_LOCAL_APIC
+	default y
+	help
+	   Additional support for AMD specific MCE features such as
+	   the DRAM Error Threshold.
+
 config PHYSICAL_START
 	hex "Physical address where the kernel is loaded" if EMBEDDED
 	default "0x100000"