Import of the watch repository from Pebble

src/libos/include/mcu/privilege.h

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2024 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <stdbool.h>
+
+inline static bool mcu_state_is_thread_privileged(void);
+
+//! Update the thread mode privilege bit in the control register. Note that you
+//! must already be privileged to call this with a true argument.
+void mcu_state_set_thread_privilege(bool privilege);
+
+bool mcu_state_is_privileged(void);
+
+#ifdef __arm__
+#include "mcu/privilege_arm.inl.h"
+#else
+#include "mcu/privilege_stubs.inl.h"
+#endif