Kev Mann / mbed-dev-OS5_10_4

RTC auf true

hal/mbed_critical_section_api.c@2:7aab896b1a3b, 2019-03-13 (annotated)

Committer:
kevman
Date:
Wed Mar 13 11:03:24 2019 +0000
Revision:
2:7aab896b1a3b
Parent:
0:38ceb79fef03 
2019-03-13

Who changed what in which revision?

UserRevisionLine numberNew contents of line
kevman 0:38ceb79fef03 1 /* mbed Microcontroller Library
kevman 0:38ceb79fef03 2 * Copyright (c) 2017 ARM Limited
kevman 0:38ceb79fef03 3 *
kevman 0:38ceb79fef03 4 * Licensed under the Apache License, Version 2.0 (the "License");
kevman 0:38ceb79fef03 5 * you may not use this file except in compliance with the License.
kevman 0:38ceb79fef03 6 * You may obtain a copy of the License at
kevman 0:38ceb79fef03 7 *
kevman 0:38ceb79fef03 8 * http://www.apache.org/licenses/LICENSE-2.0
kevman 0:38ceb79fef03 9 *
kevman 0:38ceb79fef03 10 * Unless required by applicable law or agreed to in writing, software
kevman 0:38ceb79fef03 11 * distributed under the License is distributed on an "AS IS" BASIS,
kevman 0:38ceb79fef03 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
kevman 0:38ceb79fef03 13 * See the License for the specific language governing permissions and
kevman 0:38ceb79fef03 14 * limitations under the License.
kevman 0:38ceb79fef03 15 */
kevman 0:38ceb79fef03 16 #include "cmsis.h"
kevman 0:38ceb79fef03 17 #include "hal/critical_section_api.h"
kevman 0:38ceb79fef03 18 #include "platform/mbed_assert.h"
kevman 0:38ceb79fef03 19 #include "platform/mbed_toolchain.h"
kevman 0:38ceb79fef03 20
kevman 0:38ceb79fef03 21 #include <stdbool.h>
kevman 0:38ceb79fef03 22
kevman 0:38ceb79fef03 23 static volatile bool critical_interrupts_enabled = false;
kevman 0:38ceb79fef03 24 static volatile bool state_saved = false;
kevman 0:38ceb79fef03 25
kevman 0:38ceb79fef03 26 static bool are_interrupts_enabled(void)
kevman 0:38ceb79fef03 27 {
kevman 0:38ceb79fef03 28 #if defined(__CORTEX_A9)
kevman 0:38ceb79fef03 29 return ((__get_CPSR() & 0x80) == 0);
kevman 0:38ceb79fef03 30 #else
kevman 0:38ceb79fef03 31 return ((__get_PRIMASK() & 0x1) == 0);
kevman 0:38ceb79fef03 32 #endif
kevman 0:38ceb79fef03 33 }
kevman 0:38ceb79fef03 34
kevman 0:38ceb79fef03 35
kevman 0:38ceb79fef03 36 MBED_WEAK void hal_critical_section_enter(void)
kevman 0:38ceb79fef03 37 {
kevman 0:38ceb79fef03 38 const bool interrupt_state = are_interrupts_enabled();
kevman 0:38ceb79fef03 39
kevman 0:38ceb79fef03 40 __disable_irq();
kevman 0:38ceb79fef03 41
kevman 0:38ceb79fef03 42 if (state_saved == true) {
kevman 0:38ceb79fef03 43 return;
kevman 0:38ceb79fef03 44 }
kevman 0:38ceb79fef03 45
kevman 0:38ceb79fef03 46 critical_interrupts_enabled = interrupt_state;
kevman 0:38ceb79fef03 47 state_saved = true;
kevman 0:38ceb79fef03 48 }
kevman 0:38ceb79fef03 49
kevman 0:38ceb79fef03 50 MBED_WEAK void hal_critical_section_exit(void)
kevman 0:38ceb79fef03 51 {
kevman 0:38ceb79fef03 52 // Interrupts must be disabled on invoking an exit from a critical section
kevman 0:38ceb79fef03 53 MBED_ASSERT(!are_interrupts_enabled());
kevman 0:38ceb79fef03 54 state_saved = false;
kevman 0:38ceb79fef03 55
kevman 0:38ceb79fef03 56 // Restore the IRQs to their state prior to entering the critical section
kevman 0:38ceb79fef03 57 if (critical_interrupts_enabled == true) {
kevman 0:38ceb79fef03 58 __enable_irq();
kevman 0:38ceb79fef03 59 }
kevman 0:38ceb79fef03 60 }
kevman 0:38ceb79fef03 61
kevman 0:38ceb79fef03 62 MBED_WEAK bool hal_in_critical_section(void)
kevman 0:38ceb79fef03 63 {
kevman 0:38ceb79fef03 64 return (state_saved == true);
kevman 0:38ceb79fef03 65 }