diff --git a/src/soc/intel/skylake/chip.c b/src/soc/intel/skylake/chip.c
index 549f403..89eaef5 100644
--- a/src/soc/intel/skylake/chip.c
+++ b/src/soc/intel/skylake/chip.c
@@ -320,16 +320,11 @@
 		 */
 		params->SpiFlashCfgLockDown = 0;
 	}
-	/* only replacing preexisting subsys ID defaults when non-zero */
-	if (CONFIG_SUBSYSTEM_VENDOR_ID != 0) {
-		params->DefaultSvid = CONFIG_SUBSYSTEM_VENDOR_ID;
-		params->PchSubSystemVendorId = CONFIG_SUBSYSTEM_VENDOR_ID;
-	}
-
-	if (CONFIG_SUBSYSTEM_DEVICE_ID != 0) {
-		params->DefaultSid = CONFIG_SUBSYSTEM_DEVICE_ID;
-		params->PchSubSystemId = CONFIG_SUBSYSTEM_DEVICE_ID;
-	}
+	/* FSP should let coreboot set subsystem IDs, which are read/write-once */
+	params->DefaultSvid = 0;
+	params->PchSubSystemVendorId = 0;
+	params->DefaultSid = 0;
+	params->PchSubSystemId = 0;
 
 	params->PchPmWolEnableOverride = config->WakeConfigWolEnableOverride;
 	params->PchPmPcieWakeFromDeepSx = config->WakeConfigPcieWakeFromDeepSx;