mbed-os/core/util/critical/critical_nordic.c

89 lines
2.6 KiB
C

/*
* Copyright (c) 2015-2016, ARM Limited, All Rights Reserved
* SPDX-License-Identifier: Apache-2.0
*
* 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.
*/
#ifdef TARGET_NORDIC
#include <stdint.h>
#include <stddef.h>
#include "cmsis.h"
#include <assert.h>
#include <stdbool.h>
#include <nrf_soc.h>
#include <nrf_sdm.h>
#include "critical.h"
static volatile union {
uint32_t _PRIMASK_state;
uint8_t _sd_state;
} _state = { 0 } ;
static volatile uint32_t _entry_count = 0;
static volatile bool _use_softdevice_routine = false;
void core_util_critical_section_enter()
{
// if a critical section has already been entered, just update the counter
if (_entry_count) {
++_entry_count;
return;
}
// in this path, a critical section has never been entered
uint32_t primask = __get_PRIMASK();
// if interrupts are enabled, try to use the soft device
uint8_t sd_enabled;
if ((primask == 0) && (sd_softdevice_is_enabled(&sd_enabled) == NRF_SUCCESS) && sd_enabled == 1) {
// if the soft device can be use, use it
sd_nvic_critical_region_enter(&_state._sd_state);
_use_softdevice_routine = true;
} else {
// if interrupts where enabled, disable them
if(primask == 0) {
__disable_irq();
}
// store the PRIMASK state, it will be restored at the end of the critical section
_state._PRIMASK_state = primask;
_use_softdevice_routine = false;
}
assert(_entry_count == 0); // entry count should always be equal to 0 at this point
++_entry_count;
}
void core_util_critical_section_exit()
{
assert(_entry_count > 0);
--_entry_count;
// If their is other segments which have entered the critical section, just leave
if (_entry_count) {
return;
}
// This is the last segment of the critical section, state should be restored as before entering
// the critical section
if (_use_softdevice_routine) {
sd_nvic_critical_region_exit(_state._sd_state);
} else {
__set_PRIMASK(_state._PRIMASK_state);
}
}
#endif //TARGET_NORDIC