[coreboot-gerrit] Change in coreboot[master]: soc/intel/tigerlake/apci: Only use SCM for ChromeOS

[Tim Wawrzynczak (Code Review)]

Tim Wawrzynczak has submitted this change. ( https://review.coreboot.org/c/coreboot/+/58798 )

Change subject: soc/intel/tigerlake/apci: Only use SCM for ChromeOS
......................................................................

soc/intel/tigerlake/apci: Only use SCM for ChromeOS

Software Connection Manager doesn't work with Linux 5.13 or later and
results in TBT ports timing out. Not advertising this results in
Firmware Connection Manager being used and TBT works correctly.

Linux patch:
https://github.com/torvalds/linux/commit/c6da62a219d028de10f2e22e93a34c7ee2b...

Tested on:
* StarBook Mk V
* System76 Oryx Pro 8

Signed-off-by: Sean Rhodes 
Change-Id: Ib947c3c9cd843e54d4664509c15336178c0bc99e
Reviewed-on: https://review.coreboot.org/c/coreboot/+/58798
Tested-by: build bot (Jenkins) 
Reviewed-by: Tim Wawrzynczak 
Reviewed-by: Tim Crawford 
---
M src/soc/intel/tigerlake/acpi/tcss.asl
1 file changed, 7 insertions(+), 0 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Tim Wawrzynczak: Looks good to me, approved
  Tim Crawford: Looks good to me, but someone else must approve

diff --git a/src/soc/intel/tigerlake/acpi/tcss.asl b/src/soc/intel/tigerlake/acpi/tcss.asl
index 2a71b31..cdbf0cc 100644
--- a/src/soc/intel/tigerlake/acpi/tcss.asl
+++ b/src/soc/intel/tigerlake/acpi/tcss.asl
@@ -154,6 +154,12 @@
    			CDW1 |= UNRECOGNIZED_REVISION
    		}
    		Return (Arg3)
+#if CONFIG(CHROMEOS)
+		/*
+		 * Software Connection Manager doesn't work with Linux 5.13 or later and
+		 * results in TBT ports timing out. Not advertising this results in
+		 * Firmware Connection Manager being used and TBT works correctly.
+		 */
    	} ElseIf (Arg0 == ToUUID("23A0D13A-26AB-486C-9C5F-0FFA525A575A")) {
    		/*
    		 * Operating System Capabilities for USB4
@@ -185,6 +191,7 @@
    			INTER_DOMAIN_USB4_INTERNET_PROTOCOL
    		CDW3 = Local0
    		Return (Arg3)
+#endif
    	} Else {
    		CDW1 |= UNRECOGNIZED_UUID
    		Return (Arg3)