soc/intel/common: Add _DSM methods for LPIT table

This patch adds _DSM Method in LPIT table for entering and exiting
S0ix. This method get injected into DSDT table and called from kernel.

LPIT table is hardcoded in this patch but the proper way to implement
is to use inject_dsdt to make the _DSM methods available for soc's to
implement.

Calling the LPIT table from mainboard here so that with the current
implementation the platforms which do not have lpit support throw
compilation error.

BUG=b:148892882
BRANCH=none
TEST="BUILD"

Signed-off-by: Venkata Krishna Nimmagadda <venkata.krishna.nimmagadda@intel.com>
Change-Id: Ib58f2e33a33bac9cc5f6aca28e85a8066413a5cf
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40259
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Venkata Krishna Nimmagadda <Venkata.krishna.nimmagadda@intel.com>

src/soc/intel/common/acpi/lpit.asl

@@ -0,0 +1,104 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* This file is part of the coreboot project. */
+
+#define LPID_DSM_ARG2_ENUM_FUNCTIONS 0
+#define LPID_DSM_ARG2_GET_DEVICE_CONSTRAINTS 1
+
+#define LPID_DSM_ARG2_GET_CRASH_DUMP_DEV 2
+#define LPID_DSM_ARG2_DISPLAY_OFF_NOTIFY 3
+#define LPID_DSM_ARG2_DISPLAY_ON_NOTIFY 4
+#define LPID_DSM_ARG2_S0IX_ENTRY 5
+#define LPID_DSM_ARG2_S0IX_EXIT 6
+
+External(\_SB.MS0X, MethodObj)
+External(\_SB.PCI0.LPCB.EC0.S0IX, MethodObj)
+External(\_SB.PCI0.EGPM, MethodObj)
+External(\_SB.PCI0.RGPM, MethodObj)
+
+Scope(\_SB)
+{
+	Device(LPID)
+	{
+		Name(_ADR, 0x00000000)
+		Name(_CID, EISAID("PNP0D80"))
+		Name(UUID, ToUUID("c4eb40a0-6cd2-11e2-bcfd-0800200c9a66"))
+		Method(_DSM, 4)
+		{
+			If(Arg0 == ^UUID) {
+			/*
+			 * Enum functions
+			 */
+			If(Arg2 == LPID_DSM_ARG2_ENUM_FUNCTIONS) {
+				Return(Buffer(One) {0x60})
+			}
+			/*
+			 * Function 1 - Get Device Constraints
+			 */
+			If(Arg2 == LPID_DSM_ARG2_GET_DEVICE_CONSTRAINTS) {
+				Return(Package(5) {0, Ones, Ones, Ones, Ones})
+			}
+			/*
+			 * Function 2 - Get Crash Dump Device
+			 */
+			If(Arg2 == LPID_DSM_ARG2_GET_CRASH_DUMP_DEV) {
+				Return(Buffer(One) {0x0})
+			}
+			/*
+			 * Function 3 - Display Off Notification
+			 */
+			If(Arg2 == LPID_DSM_ARG2_DISPLAY_OFF_NOTIFY) {
+			}
+			/*
+			 * Function 4 - Display On Notification
+			 */
+			If(Arg2 == LPID_DSM_ARG2_DISPLAY_ON_NOTIFY) {
+			}
+			/*
+			 * Function 5 - Low Power S0 Entry Notification
+			 */
+			If(Arg2 == LPID_DSM_ARG2_S0IX_ENTRY) {
+				/* Inform the EC */
+				If (CondRefOf (\_SB.PCI0.LPCB.EC0.S0IX)) {
+					\_SB.PCI0.LPCB.EC0.S0IX(1)
+				}
+
+				/* provide board level S0ix hook */
+				If (CondRefOf (\_SB.MS0X)) {
+					\_SB.MS0X(1)
+				}
+
+				/*
+				 * Save the current PM bits then
+				 * enable GPIO PM with MISCCFG_ENABLE_GPIO_PM_CONFIG
+ 				 */
+				If (CondRefOf (\_SB.PCI0.EGPM))
+				{
+					\_SB.PCI0.EGPM ()
+				}
+			}
+			/*
+			 * Function 6 - Low Power S0 Exit Notification
+			 */
+			If(Arg2 == LPID_DSM_ARG2_S0IX_EXIT) {
+				/* Inform the EC */
+				If (CondRefOf (\_SB.PCI0.LPCB.EC0.S0IX)) {
+					\_SB.PCI0.LPCB.EC0.S0IX(0)
+				}
+
+				/* provide board level S0ix hook */
+				If (CondRefOf (\_SB.MS0X)) {
+					\_SB.MS0X(0)
+				}
+
+				/* Restore GPIO all Community PM */
+				If (CondRefOf (\_SB.PCI0.RGPM))
+				{
+					\_SB.PCI0.RGPM ()
+				}
+			}
+		}
+
+		Return(Buffer(One) {0x00})
+		}		// Method(_DSM)
+	}			// Device (LPID)
+}				// End Scope(\_SB)