[coreboot-gerrit] Change in coreboot[master]: soc/intel/common/acpi: correct return value for PEPD enum function

[Nico Huber (Code Review)]

Nico Huber has submitted this change. ( https://review.coreboot.org/c/coreboot/+/47140 )

Change subject: soc/intel/common/acpi: correct return value for PEPD enum function
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soc/intel/common/acpi: correct return value for PEPD enum function

The PEPD enum function returns a bitmask to announce supported/enabled
PEPD functions. Add a comment describing this bitmask and correct the
return value to announce function 1, 5 and 6 as supported.

Also add comments to the disabled functions 3 and 4.

Change-Id: Ib523a54f5ad695e79005aba422282e03f2bc4bed
Signed-off-by: Michael Niewöhner 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/47140
Tested-by: build bot (Jenkins) 
Reviewed-by: Furquan Shaikh 
---
M src/soc/intel/common/block/acpi/acpi/pep.asl
1 file changed, 9 insertions(+), 1 deletion(-)

Approvals:
  build bot (Jenkins): Verified
  Furquan Shaikh: Looks good to me, approved

diff --git a/src/soc/intel/common/block/acpi/acpi/pep.asl b/src/soc/intel/common/block/acpi/acpi/pep.asl
index 9e39a8f..ef67076 100644
--- a/src/soc/intel/common/block/acpi/acpi/pep.asl
+++ b/src/soc/intel/common/block/acpi/acpi/pep.asl
@@ -26,7 +26,12 @@
    		 * Enum functions
    		 */
    		If(Arg2 == PEPD_DSM_LPI_ENUM_FUNCTIONS) {
-				Return(Buffer(One) {0x60})
+				/*
+				 * Supported functions bitmask
+				 * bit 0:    other functions than 0 are supported
+				 * bits 1-6: function x supported
+				 */
+				Return(Buffer(1) {0x63})
    		}
    		/*
    		 * Function 1 - Get Device Constraints
@@ -56,16 +61,19 @@
    		 * Function 2 - Get Crash Dump Device
    		 */
    		If(Arg2 == PEPD_DSM_LPI_GET_CRASH_DUMP_DEV) {
+				/* not yet used and not advertised by function 0 */
    		}
    		/*
    		 * Function 3 - Display Off Notification
    		 */
    		If(Arg2 == PEPD_DSM_LPI_DISPLAY_OFF_NOTIFY) {
+				/* not yet used and not advertised by function 0 */
    		}
    		/*
    		 * Function 4 - Display On Notification
    		 */
    		If(Arg2 == PEPD_DSM_LPI_DISPLAY_ON_NOTIFY) {
+				/* not yet used and not advertised by function 0 */
    		}
    		/*
    		 * Function 5 - Low Power S0 Entry Notification