diff --git a/src/arch/x86/acpigen.c b/src/arch/x86/acpigen.c
index 74cd25a858..f9af10229e 100644
--- a/src/arch/x86/acpigen.c
+++ b/src/arch/x86/acpigen.c
@@ -1115,7 +1115,7 @@ void acpigen_write_uuid(const char *uuid)
 void acpigen_write_power_res(const char *name, uint8_t level, uint16_t order,
 			     const char *dev_states[], size_t dev_states_count)
 {
-	int i;
+	size_t i;
 	for (i = 0; i < dev_states_count; i++) {
 		acpigen_write_name(dev_states[i]);
 		acpigen_write_package(1);