[coreboot-gerrit] Change in coreboot[master]: nb/amd/agesa/family14/acpi/thermal_mixin.asl: handle HTC threshold be...

[Michał Żygowski (Code Review)]

Michał Żygowski has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/39697 )

Change subject: nb/amd/agesa/family14/acpi/thermal_mixin.asl: handle HTC threshold better
......................................................................

nb/amd/agesa/family14/acpi/thermal_mixin.asl: handle HTC threshold better

According to BKDGs HTC temperature limit field indicates the threshold
where HTC becomes active. HTC active state means that processor is limiting
its power consumption and maximum P-State. Using this threshold as _CRT is
incorrect, since HTC active is designed to prevent overheating, not causing
immediate shutdown.

Change the behavior of temperature limit to act as a passive cooling
threshold. Make the passive cooling threshold a reference value for
critical and hot temperature with 5 degrees step.

Signed-off-by: Michał Żygowski 
Change-Id: Ife64c3aab76f8e125493ecc8183a6e87fb012e3b
---
M src/northbridge/amd/agesa/family14/acpi/thermal_mixin.asl
1 file changed, 12 insertions(+), 3 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/97/39697/1

diff --git a/src/northbridge/amd/agesa/family14/acpi/thermal_mixin.asl b/src/northbridge/amd/agesa/family14/acpi/thermal_mixin.asl
index 1f877cc..714fb45 100644
--- a/src/northbridge/amd/agesa/family14/acpi/thermal_mixin.asl
+++ b/src/northbridge/amd/agesa/family14/acpi/thermal_mixin.asl
@@ -35,7 +35,7 @@
  */

#ifndef K10TEMP_HOT_OFFSET
-# define K10TEMP_HOT_OFFSET	100
+# define K10TEMP_HOT_OFFSET	50
 #endif

#define K10TEMP_KELVIN_OFFSET	2732
@@ -71,7 +71,12 @@
    	Return (Add (Local0, K10TEMP_KELVIN_OFFSET))
    }

-	Method (_CRT) {	/* Critical temp in tenths degree Kelvin. */
+	/* 
+	 * TLMT indicates threshold where HTC become active. That is the 
+	 * processor will limit P-State and power consumption in order to
+	 * cool down.
+	 */
+	Method (_PSV) {
    	Multiply (TLMT, 10, Local0)
    	ShiftRight (Local0, 1, Local0)
    	Add (Local0, K10TEMP_TLIMIT_OFFSET, Local0)
@@ -79,6 +84,10 @@
    }

Method (_HOT) {	/* Hot temp in tenths degree Kelvin. */
-		Return (Subtract (_CRT, K10TEMP_HOT_OFFSET))
+		Return (Add (_PSV, K10TEMP_HOT_OFFSET))
+	}
+
+	Method (_CRT) {	/* Critical temp in tenths degree Kelvin. */
+		Return (Add (_HOT, K10TEMP_HOT_OFFSET))
    }
 }