[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>

1 files changed, 10 insertions, 0 deletions

diff --git a/arch/x86_64/kernel/apic.c b/arch/x86_64/kernel/apic.c
index b6e7715d877f..18691ce4c759 100644
--- a/arch/x86_64/kernel/apic.c
+++ b/arch/x86_64/kernel/apic.c
@@ -833,6 +833,16 @@ int setup_profiling_timer(unsigned int multiplier)
         return 0;
 }
 
+#ifdef CONFIG_X86_MCE_AMD
+void setup_threshold_lvt(unsigned long lvt_off)
+{
+        unsigned int v = 0;
+        unsigned long reg = (lvt_off << 4) + 0x500;
+        v |= THRESHOLD_APIC_VECTOR;
+        apic_write(reg, v);
+}
+#endif /* CONFIG_X86_MCE_AMD */
+
 #undef APIC_DIVISOR
 
 /*