| // Copyright 2020 The Pigweed Authors |
| // |
| // 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 |
| // |
| // https://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 <cstdint> |
| |
| #include "pw_preprocessor/arch.h" |
| |
| namespace pw::interrupt { |
| |
| #if !_PW_ARCH_ARM_CORTEX_M |
| #error You can only build this for ARM Cortex-M architectures. If you are \ |
| trying to do this and are still seeing this error, see \ |
| pw_preprocessor/arch.h |
| #endif // !_PW_ARCH_ARM_CORTEX_M |
| |
| #if _PW_ARCH_ARM_V6M || _PW_ARCH_ARM_V7M || _PW_ARCH_ARM_V7EM || \ |
| _PW_ARCH_ARM_V8M_BASELINE || _PW_ARCH_ARM_V8M_MAINLINE || \ |
| _PW_ARCH_ARM_V8_1M_MAINLINE |
| inline bool InInterruptContext() { |
| // ARMv7M Reference manual section B1.4.2 describes how the Interrupt |
| // Program Status Register (IPSR) is zero if there is no exception (interrupt) |
| // being processed. |
| uint32_t ipsr; |
| asm volatile("MRS %0, ipsr" : "=r"(ipsr)); |
| return ipsr != 0; |
| } |
| #else |
| #error "Your selected ARM Cortex-M arch is not yet supported by this module." |
| #endif |
| |
| } // namespace pw::interrupt |
