[coreboot-gerrit] [M] Change in coreboot[master]: soc/intel/xeon_sp/acpi: Fix _OSC method

[Felix Held (Code Review)]

Felix Held has submitted this change. ( https://review.coreboot.org/c/coreboot/+/74231 )

Change subject: soc/intel/xeon_sp/acpi: Fix _OSC method
......................................................................

soc/intel/xeon_sp/acpi: Fix _OSC method

Fix a couple of bugs in the _OSC method for handling
"PCI Host Bridge Device" on Xeon-SP.

- Drop the Sleep. The code doesn't write to hardware at all, so
  there's no need to sleep here.
- Make sure that the number of DWORD passed in Arg2 is at least 3.
  The existing check was useless as it would not create the
  DWordField, but then use it anyways.
- Add check for CXL 2 device method calls which provide a 5 DWORD
  long buffer to prevent buffer overflows when invoking the
  "PCI Host Bridge Device" method.

Test:
Boot on Archer City and confirm that no ACPI errors are reported
for _OSC.

Change-Id: Ide598e386c30ced24e4f96c37f2b4a609ac33441
Signed-off-by: Patrick Rudolph 
Reviewed-on: https://review.coreboot.org/c/coreboot/+/74231
Tested-by: build bot (Jenkins) 
Reviewed-by: Jonathan Zhang 
---
M src/soc/intel/xeon_sp/acpi/iiostack.asl
M src/soc/intel/xeon_sp/spr/acpi/cxl_resource.asl
M src/soc/intel/xeon_sp/spr/acpi/pci_resource.asl
3 files changed, 58 insertions(+), 19 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Jonathan Zhang: Looks good to me, approved

diff --git a/src/soc/intel/xeon_sp/acpi/iiostack.asl b/src/soc/intel/xeon_sp/acpi/iiostack.asl
index 91a5c6c..e5e6bdc 100644
--- a/src/soc/intel/xeon_sp/acpi/iiostack.asl
+++ b/src/soc/intel/xeon_sp/acpi/iiostack.asl
@@ -27,17 +27,18 @@
    		CreateDWordField (Arg3, 0x00, CDW1)		\
    		If ((Arg0 == ToUUID ("33db4d5b-1ff7-401c-9657-7441c03dd766") /* PCI Host Bridge Device */))  \
    		{							\
-				CreateDWordField (Arg3, 0x04, CDW2)		\
-				If ((Arg2 > 0x02))				\
+				If (Arg2 < 0x03)				\
    			{						\
-					CreateDWordField (Arg3, 0x08, CDW3)	\
+					CDW1 |= 0x02 /* Unknown failure */	\
+					Return (Arg3)				\
    			}						\
+				CreateDWordField (Arg3, 0x04, CDW2)		\
+				CreateDWordField (Arg3, 0x08, CDW3)		\
    			SUPP = CDW2					\
    			CTRL = CDW3					\
    			If ((AHPE || ((SUPP & 0x16) != 0x16)))		\
    			{						\
    				CTRL &= 0x1E				\
-					Sleep (0x03E8)				\
    			}						\
    			/* Never allow SHPC (no SHPC controller in system) */ \
    			CTRL &= 0x1D					\
diff --git a/src/soc/intel/xeon_sp/spr/acpi/cxl_resource.asl b/src/soc/intel/xeon_sp/spr/acpi/cxl_resource.asl
index 299247f..3644e87 100644
--- a/src/soc/intel/xeon_sp/spr/acpi/cxl_resource.asl
+++ b/src/soc/intel/xeon_sp/spr/acpi/cxl_resource.asl
@@ -40,24 +40,28 @@
    {
    	CreateDWordField (Arg3, 0x00, CDW1)
    	If (Arg0 == ToUUID ("33db4d5b-1ff7-401c-9657-7441c03dd766") /* PCI Host Bridge Device */
-			|| Arg0 == ToUUID ("68f2d50b-c469-4d8a-bd3d-941a103fd3fc"))
-			/* CXL */
+			|| Arg0 == ToUUID ("68f2d50b-c469-4d8a-bd3d-941a103fd3fc")) /* CXL 2.0 */
    	{
-			CreateDWordField (Arg3, 0x04, CDW2)
-			If (Arg2 > 0x02)
+			If (Arg2 < 0x03) /* Number of DWORDs in Arg3 must be at least 3 */
    		{
-				CreateDWordField (Arg3, 0x08, CDW3)
-				CreateDWordField (Arg3, 0x0C, CDW4)
-				CreateDWordField (Arg3, 0x10, CDW5)
+				CDW1 |= 0x02 /* Unknown failure */
+				Return (Arg3)
    		}
+			CreateDWordField (Arg3, 0x04, CDW2)
+			CreateDWordField (Arg3, 0x08, CDW3)
+
    		SUPP = CDW2
    		CTRL = CDW3
-			SUPC = CDW4
-			CTRC = CDW5
+			If (Arg0 == ToUUID ("68f2d50b-c469-4d8a-bd3d-941a103fd3fc")) /* CXL 2.0 */
+			{
+				CreateDWordField (Arg3, 0x0C, CDW4)
+				CreateDWordField (Arg3, 0x10, CDW5)
+				SUPC = CDW4
+				CTRC = CDW5
+			}
    		If (SUPP & 0x16 != 0x16)
    		{
    			CTRL &= 0x1E
-				Sleep (0x03E8)
    		}
    		/* Never allow SHPC (no SHPC controller in system) */
    		CTRL &= 0x1D
@@ -72,7 +76,10 @@
    			CDW1 |= 0x10
    		}
    		CDW3 = CTRL
-			CDW5 = CTRC
+			If (Arg0 == ToUUID ("68f2d50b-c469-4d8a-bd3d-941a103fd3fc")) /* CXL 2.0 */
+			{
+				CDW5 = CTRC
+			}
    		Return (Arg3)
    	}
    	Else
diff --git a/src/soc/intel/xeon_sp/spr/acpi/pci_resource.asl b/src/soc/intel/xeon_sp/spr/acpi/pci_resource.asl
index 7988a16..a369b11 100644
--- a/src/soc/intel/xeon_sp/spr/acpi/pci_resource.asl
+++ b/src/soc/intel/xeon_sp/spr/acpi/pci_resource.asl
@@ -35,17 +35,19 @@
    	CreateDWordField (Arg3, 0x00, CDW1)
    	If (Arg0 == ToUUID ("33db4d5b-1ff7-401c-9657-7441c03dd766") /* PCI Host Bridge Device */)
    	{
-			CreateDWordField (Arg3, 0x04, CDW2)
-			If (Arg2 > 0x02)
+			If (Arg2 < 0x03) /* Number of DWORDs in Arg3 must be at least 3 */
    		{
-				CreateDWordField (Arg3, 0x08, CDW3)
+				CDW1 |= 0x02 /* Unknown failure */
+				Return (Arg3)
    		}
+			CreateDWordField (Arg3, 0x04, CDW2)
+			CreateDWordField (Arg3, 0x08, CDW3)
+
    		SUPP = CDW2
    		CTRL = CDW3
    		If (SUPP & 0x16 != 0x16)
    		{
    			CTRL &= 0x1E
-				Sleep (0x03E8)
    		}
    		/* Never allow SHPC (no SHPC controller in system) */
    		CTRL &= 0x1D