amd/mendocino/acpi/soc: Add DPTC Support

Add support for DPTC by calling SB.DPTC() as part of PNOT().

BRANCH=none
BUG=b:217911928
TEST=Boot skyrim

Signed-off-by: Tim Van Patten <timvp@google.com>
Change-Id: Ifc332bfc4d273031c93b77673224b4f3c2871fb1
Reviewed-on: https://review.coreboot.org/c/coreboot/+/67694
Reviewed-by: Raul Rangel <rrangel@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/amd/mendocino/acpi/soc.asl

@@ -35,6 +35,9 @@ Scope(\_SB) {
 
 #include "rtc_workaround.asl"
 
+/* Enable DPTC interface with AMD ALIB */
+External(\_SB.DPTC, MethodObj)
+
 /*
  * Platform Notify
  *
@@ -44,4 +47,8 @@ Method (PNOT)
 {
 	/* Report AC/DC state to ALIB using WAL1() */
 	\WAL1 ()
+
+	If (CondRefOf (\_SB.DPTC)) {
+		\_SB.DPTC()
+	}
 }