mainboard/volteer: Enable SaGv for volteer2, delbin & voxel

SaGv needs to be enabled for only QS. On ES2, we are seeing system
instability.

BUG=b:159198381
TEST=Tested for boot. Power and performance tests were run with
volteer2 with qs setup. System showed stability.
Tested for boot stability on on delbin.

Change-Id: I1bce3b9f837fb19ba5a20ae31750a73474a86788
Signed-off-by: Shreesh Chhabbi <shreesh.chhabbi@intel.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/42483
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Caveh Jalali <caveh@chromium.org>

src/mainboard/google/volteer/variants/baseboard/devicetree.cb

@@ -47,7 +47,7 @@ chip soc/intel/tigerlake
 	register "HeciEnabled" = "1"
 
 	# FSP configuration
-	register "SaGv" = "SaGv_Disabled"
+	register "SaGv" = "SaGv_Enabled"
 	register "SmbusEnable" = "0"
 
 	register "usb2_ports[0]" = "USB2_PORT_MID(OC_SKIP)"	# Type-A Port A0

src/mainboard/google/volteer/variants/delbin/overridetree.cb

@@ -1,5 +1,4 @@
 chip soc/intel/tigerlake
-
 	device domain 0 on
 	end
 

src/mainboard/google/volteer/variants/halvor/overridetree.cb

@@ -15,6 +15,8 @@ chip soc/intel/tigerlake
 	register "usb3_ports[2]" = "USB3_PORT_DEFAULT(OC2)"	# Type-A / Type-C Port 2
 	register "usb3_ports[3]" = "USB3_PORT_EMPTY"		# Type-A / Type-C Not Used
 
+	register "SaGv" = "SaGv_Disabled"
+
 	device domain 0 on
 		device pci 15.0 on
 			chip drivers/i2c/generic

src/mainboard/google/volteer/variants/malefor/overridetree.cb

@@ -17,6 +17,8 @@ chip soc/intel/tigerlake
 	register "usb3_ports[2]" = "USB3_PORT_EMPTY"		# Type-A / Type-C Not Used
 	register "usb3_ports[3]" = "USB3_PORT_EMPTY"		# Type-A / Type-C Not Used
 
+	register "SaGv" = "SaGv_Disabled"
+
 	# I2C Port Config
 	register "SerialIoI2cMode" = "{
 		[PchSerialIoIndexI2C0]  = PchSerialIoPci,

src/mainboard/google/volteer/variants/terrador/overridetree.cb

@@ -17,6 +17,8 @@ chip soc/intel/tigerlake
 	register "usb3_ports[2]" = "USB3_PORT_EMPTY"		# Type-A / Type-C Not Used
 	register "usb3_ports[3]" = "USB3_PORT_EMPTY"		# Type-A / Type-C Not Used
 
+	register "SaGv" = "SaGv_Disabled"
+
 	device domain 0 on
 		device pci 15.0 on
 			chip drivers/i2c/generic

src/mainboard/google/volteer/variants/trondo/overridetree.cb

@@ -1,4 +1,5 @@
 chip soc/intel/tigerlake
+	register "SaGv" = "SaGv_Disabled"
 	device domain 0 on
 		device pci 15.1 on
 			chip drivers/i2c/hid

src/mainboard/google/volteer/variants/volteer/overridetree.cb

@@ -1,4 +1,5 @@
 chip soc/intel/tigerlake
+	register "SaGv" = "SaGv_Disabled"
 	device domain 0 on
 		device pci 15.0 on
 			chip drivers/i2c/generic