drivers/genesyslogic/gl9755: Disable debug mode to enable circuit protections

In order for short circuit protection and over current protection to work, the
debug mode needs to be turned off.

BUG=b:185749961
TEST=build and test

Signed-off-by: Ben Chuang <benchuanggli@gmail.com>
Change-Id: Iacfa3c668a52d1bae15fe82f1c614d0ebd93a957
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51000
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>
Reviewed-by: Nick Vaccaro <nvaccaro@google.com>
diff --git a/src/drivers/genesyslogic/gl9755/gl9755.c b/src/drivers/genesyslogic/gl9755/gl9755.c
index 6dfac47..a5778e3 100644
--- a/src/drivers/genesyslogic/gl9755/gl9755.c
+++ b/src/drivers/genesyslogic/gl9755/gl9755.c
@@ -28,6 +28,9 @@
 	reg |= CFG2_LAT_L1_64US;
 	pci_write_config32(dev, CFG2, reg);
 
+	/* Turn off debug mode to enable SCP/OCP */
+	pci_and_config32(dev, CFG3, ~SCP_DEBUG);
+
 	/* Set Vendor Config to be non-configurable */
 	pci_and_config32(dev, CFG, ~CFG_EN);
 }