mb/google/sarien: Add SKU for boards with signed EC

To support both boards with the same firmware add a SKU for
each variant that is used to include the proper EC firmware
image to match what the EC is expecting.

BUG=b:119490232
TEST=tested by faking the EC response to ensure that the OS
and firmware update tools are able to determine the correct
model based on the value returned by the EC.

Change-Id: Iaa677975e0bccbee5ec8a39821fe1637f08270fa
Signed-off-by: Duncan Laurie <dlaurie@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/32002
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/mainboard/google/sarien/sku.c

@@ -14,15 +14,22 @@
  */
 
 #include <boardid.h>
+#include <ec/google/wilco/commands.h>
 #include <smbios.h>
 #include <variant/variant.h>
 
 uint32_t sku_id(void)
 {
-	return VARIANT_SKU_ID;
+	if (wilco_ec_signed_fw())
+		return VARIANT_SKU_ID_SIGNED_EC;
+	else
+		return VARIANT_SKU_ID;
 }
 
 const char *smbios_system_sku(void)
 {
-	return VARIANT_SKU_NAME;
+	if (wilco_ec_signed_fw())
+		return VARIANT_SKU_NAME_SIGNED_EC;
+	else
+		return VARIANT_SKU_NAME;
 }

src/mainboard/google/sarien/variants/arcada/include/variant/variant.h

@@ -16,8 +16,10 @@
 #ifndef VARIANT_H
 #define VARIANT_H
 
-/* Arcada is SKU ID 2 */
-#define VARIANT_SKU_ID	2
-#define VARIANT_SKU_NAME "sku2"
+/* Arcada is SKU ID 2 and 4 */
+#define VARIANT_SKU_ID			2
+#define VARIANT_SKU_NAME		"sku2"
+#define VARIANT_SKU_ID_SIGNED_EC	4
+#define VARIANT_SKU_NAME_SIGNED_EC	"sku4"
 
 #endif

src/mainboard/google/sarien/variants/sarien/include/variant/variant.h

@@ -16,8 +16,10 @@
 #ifndef VARIANT_H
 #define VARIANT_H
 
-/* Sarien is SKU ID 1 */
-#define VARIANT_SKU_ID	1
-#define VARIANT_SKU_NAME "sku1"
+/* Sarien is SKU ID 1 and 3 */
+#define VARIANT_SKU_ID			1
+#define VARIANT_SKU_NAME		"sku1"
+#define VARIANT_SKU_ID_SIGNED_EC	3
+#define VARIANT_SKU_NAME_SIGNED_EC	"sku3"
 
 #endif