[S] Change in coreboot[master]: mb/google/brask: Disable PCH USB2 phy power gating for moli

[Subrata Banik (Code Review)]

Subrata Banik has submitted this change. ( https://review.coreboot.org/c/coreboot/+/69193 )

Change subject: mb/google/brask: Disable PCH USB2 phy power gating for moli
......................................................................

mb/google/brask: Disable PCH USB2 phy power gating for moli

The patch disables PCH USB2 Phy power gating to prevent possible display
flicker issue for moli board. Please refer Intel doc#723158 for
more information.

BUG=b:257373742
TEST=Verify the build for moli board

Signed-off-by: Casper Chang 
Change-Id: I457d410501be996f0f29ec622e1829f1581c4970
Reviewed-on: https://review.coreboot.org/c/coreboot/+/69193
Reviewed-by: Zhuohao Lee 
Reviewed-by: Subrata Banik 
Tested-by: build bot (Jenkins) 
Reviewed-by: Scott Chao 
---
M src/mainboard/google/brya/variants/moli/overridetree.cb
1 file changed, 25 insertions(+), 0 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Zhuohao Lee: Looks good to me, approved
  Scott Chao: Looks good to me, approved
  Subrata Banik: Looks good to me, approved

diff --git a/src/mainboard/google/brya/variants/moli/overridetree.cb b/src/mainboard/google/brya/variants/moli/overridetree.cb
index 8f1bf8e..f3b28c4 100644
--- a/src/mainboard/google/brya/variants/moli/overridetree.cb
+++ b/src/mainboard/google/brya/variants/moli/overridetree.cb
@@ -14,6 +14,9 @@
    end
 end
 chip soc/intel/alderlake
+	# As per Intel Advisory doc#723158, the change is required to prevent possible
+	# display flickering issue.
+	register "usb2_phy_sus_pg_disable" = "1"
    # Enable HDMI2 in PortA, HDMI1 in PortB, HDMI/DP in Port2
    register "ddi_ports_config" = "{
    	[DDI_PORT_A] = DDI_ENABLE_HPD | DDI_ENABLE_DDC,