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authorAlexander Couzens <lynxis@fe80.eu>2015-01-28 01:51:04 +0100
committerPeter Stuge <peter@stuge.se>2015-02-11 02:58:06 +0100
commitf251a6d7d48d9ae91d4cce7195952395762e07a8 (patch)
tree46bfb6fa03d4db3ccb8776731768b4d2e3c34aee /src/cpu/intel/model_206ax
parentc768f9231b4237652c7e91a524194847ae140b5a (diff)
downloadcoreboot-f251a6d7d48d9ae91d4cce7195952395762e07a8.tar.xz
cpu/intel: >= nehalem: add comments to msr finalize's
Improve documentation of lock down MSRs in finalize(). Most of these aren't documented in public MSRs. Change-Id: I4fc47bb9b71bdd7907aae65fc18b419a17ae8547 Signed-off-by: Alexander Couzens <lynxis@fe80.eu> Reviewed-on: http://review.coreboot.org/8294 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> Reviewed-by: Peter Stuge <peter@stuge.se>
Diffstat (limited to 'src/cpu/intel/model_206ax')
-rw-r--r--src/cpu/intel/model_206ax/finalize.c9
1 files changed, 9 insertions, 0 deletions
diff --git a/src/cpu/intel/model_206ax/finalize.c b/src/cpu/intel/model_206ax/finalize.c
index 2c215a4daf..0c1fe75ba7 100644
--- a/src/cpu/intel/model_206ax/finalize.c
+++ b/src/cpu/intel/model_206ax/finalize.c
@@ -25,6 +25,11 @@
#include <cpu/intel/speedstep.h>
#include "model_206ax.h"
+/* MSR Documentation based on
+ * "Sandy Bridge Processor Family BIOS Writer's Guide (BWG)"
+ * Document Number 504790
+ * Revision 1.6.0, June 2012 */
+
static void msr_set_bit(unsigned reg, unsigned bit)
{
msr_t msr = rdmsr(reg);
@@ -44,6 +49,7 @@ static void msr_set_bit(unsigned reg, unsigned bit)
void intel_model_206ax_finalize_smm(void)
{
+ /* Lock C-State MSR */
msr_set_bit(MSR_PMG_CST_CONFIG_CONTROL, 15);
/* Lock AES-NI only if supported */
@@ -68,6 +74,9 @@ void intel_model_206ax_finalize_smm(void)
msr_set_bit(MSR_PP1_POWER_LIMIT, 31);
#endif
+ /* Lock TM interupts - route thermal events to all processors */
msr_set_bit(MSR_MISC_PWR_MGMT, 22);
+
+ /* Lock memory configuration to protect SMM */
msr_set_bit(MSR_LT_LOCK_MEMORY, 0);
}