[S] Change in coreboot[main]: soc/intel/cmn/acpi: Add ACPI method to get LGMR address

[Subrata Banik (Code Review)]

Subrata Banik has uploaded this change for review. ( https://review.coreboot.org/c/coreboot/+/85602?usp=email )

Change subject: soc/intel/cmn/acpi: Add ACPI method to get LGMR address
......................................................................

soc/intel/cmn/acpi: Add ACPI method to get LGMR address

This patch adds an ACPI method to get the LPC Generic Memory Range
(LGMR) address. This is necessary for platforms that need to access
the LGMR from OS driver.

The new method, called GLGM, reads the LGMR address from the LPC PCI
configuration space (offset 0x98) and returns it as a 32-bit value.

BUG=b:354066052
TEST=Able to build and boot google/brox.

Change-Id: I4322cee2c608e550e233c45c68958e8a4046c361
Signed-off-by: Subrata Banik 
---
M src/soc/intel/common/block/acpi/acpi/lpc.asl
1 file changed, 16 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/coreboot refs/changes/02/85602/1

diff --git a/src/soc/intel/common/block/acpi/acpi/lpc.asl b/src/soc/intel/common/block/acpi/acpi/lpc.asl
index c4a7dd3..3e8f5a5 100644
--- a/src/soc/intel/common/block/acpi/acpi/lpc.asl
+++ b/src/soc/intel/common/block/acpi/acpi/lpc.asl
@@ -9,6 +9,22 @@
    Name (_ADR, 0x001f0000)
    Name (_DDN, "LPC Bus Device")

+	OperationRegion (LPCP, PCI_Config, 0x00, 0x100)
+	Field (LPCP, DWordAcc, NoLock, Preserve)
+	{
+		Offset(0x98),	/* LGMR */
+		LGEN, 1,	/* Enable */
+		, 15,
+		LADR, 16,	/* MADDR [31:16] */
+	}
+
+	/* Get LGMR */
+	Method (GLGM, 0, Serialized)
+	{
+		Local0 = LADR << 16
+		Return (Local0)
+	}
+
    /* DMA Controller */
    Device (DMAC)
    {