cpu/intel/model_206ax: Lock MSR_PP_CURRENT_CONFIG
Now that those registers are only written once set the lock bit to
protect it from runtime changes.
TEST: Lenovo X220 still boots.
Change-Id: I4c56a3cb322a0e75eb3dd366808068093928e10c
Signed-off-by: Patrick Rudolph <patrick.rudolph@9elements.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/78608
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
diff --git a/src/cpu/intel/model_206ax/model_206ax.h b/src/cpu/intel/model_206ax/model_206ax.h
index ecbf323..9379c29 100644
--- a/src/cpu/intel/model_206ax/model_206ax.h
+++ b/src/cpu/intel/model_206ax/model_206ax.h
@@ -73,8 +73,10 @@
#define PKG_POWER_LIMIT_TIME_MASK 0x7f
#define MSR_PP0_CURRENT_CONFIG 0x601
+#define PP0_CURRENT_LIMIT_LOCK (1U << 31)
#define PP0_CURRENT_LIMIT (112 << 3) /* 112 A */
#define MSR_PP1_CURRENT_CONFIG 0x602
+#define PP1_CURRENT_LIMIT_LOCK (1U << 31)
#define PP1_CURRENT_LIMIT_SNB (35 << 3) /* 35 A */
#define PP1_CURRENT_LIMIT_IVB (50 << 3) /* 50 A */
#define MSR_PKG_POWER_SKU_UNIT 0x606
diff --git a/src/cpu/intel/model_206ax/model_206ax_init.c b/src/cpu/intel/model_206ax/model_206ax_init.c
index 14a7965..dfe7ae5 100644
--- a/src/cpu/intel/model_206ax/model_206ax_init.c
+++ b/src/cpu/intel/model_206ax/model_206ax_init.c
@@ -206,6 +206,7 @@
msr = rdmsr(MSR_PP0_CURRENT_CONFIG);
msr.lo &= ~0x1fff;
msr.lo |= PP0_CURRENT_LIMIT;
+ msr.lo |= PP0_CURRENT_LIMIT_LOCK;
wrmsr(MSR_PP0_CURRENT_CONFIG, msr);
/* Secondary Plane Current Limit */
@@ -215,6 +216,7 @@
msr.lo |= PP1_CURRENT_LIMIT_IVB;
else
msr.lo |= PP1_CURRENT_LIMIT_SNB;
+ msr.lo |= PP1_CURRENT_LIMIT_LOCK;
wrmsr(MSR_PP1_CURRENT_CONFIG, msr);
}
}