| /* Copyright (c) 2018, Nordic Semiconductor ASA |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions are met: |
| * |
| * 1. Redistributions of source code must retain the above copyright notice, this |
| * list of conditions and the following disclaimer. |
| * |
| * 2. Redistributions in binary form must reproduce the above copyright notice, |
| * this list of conditions and the following disclaimer in the documentation |
| * and/or other materials provided with the distribution. |
| * |
| * 3. Neither the name of Nordic Semiconductor ASA nor the names of its |
| * contributors may be used to endorse or promote products derived from |
| * this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE |
| * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE |
| * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL |
| * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR |
| * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
| * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, |
| * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE |
| * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| * |
| */ |
| |
| /** |
| * @file |
| * This file implements critical sections for the RSCH module. |
| * |
| */ |
| |
| #include "nrf_802154_rsch_crit_sect.h" |
| |
| #include <assert.h> |
| #include <stdbool.h> |
| #include <stdint.h> |
| |
| #include "nrf_802154_critical_section.h" |
| #include "nrf_802154_rsch.h" |
| |
| #include <nrf.h> |
| |
| #define RSCH_EVT_NONE (rsch_prio_t)UINT8_MAX |
| |
| static volatile uint8_t m_rsch_pending_evt; ///< Indicator of pending RSCH event. |
| |
| /*************************************************************************************************** |
| * @section RSCH pending events management |
| **************************************************************************************************/ |
| |
| static void rsch_pending_evt_set(rsch_prio_t prio) |
| { |
| volatile uint8_t rsch_pending_evt; // Dummy variable to prevent compilers from removing ldrex |
| |
| do |
| { |
| rsch_pending_evt = __LDREXB(&m_rsch_pending_evt); |
| (void)rsch_pending_evt; |
| } |
| while (__STREXB((uint8_t)prio, &m_rsch_pending_evt)); |
| } |
| |
| static rsch_prio_t rsch_pending_evt_clear(void) |
| { |
| uint8_t evt_value; |
| |
| do |
| { |
| evt_value = __LDREXB(&m_rsch_pending_evt); |
| } |
| while (__STREXB(RSCH_EVT_NONE, &m_rsch_pending_evt)); |
| |
| return (rsch_prio_t)evt_value; |
| } |
| |
| static bool rsch_pending_evt_is_none(void) |
| { |
| return m_rsch_pending_evt == (uint8_t)RSCH_EVT_NONE; |
| } |
| |
| static void rsch_evt_process(rsch_prio_t evt) |
| { |
| if (evt != RSCH_EVT_NONE) |
| { |
| nrf_802154_rsch_crit_sect_prio_changed(evt); |
| } |
| } |
| |
| /*************************************************************************************************** |
| * @section Public API |
| **************************************************************************************************/ |
| |
| void nrf_802154_rsch_crit_sect_init(void) |
| { |
| m_rsch_pending_evt = RSCH_EVT_NONE; |
| } |
| |
| void nrf_802154_rsch_crit_sect_prio_request(rsch_prio_t prio) |
| { |
| nrf_802154_rsch_continuous_mode_priority_set(prio); |
| } |
| |
| /*************************************************************************************************** |
| * @section RSCH callbacks |
| **************************************************************************************************/ |
| |
| void nrf_802154_rsch_continuous_prio_changed(rsch_prio_t prio) |
| { |
| bool crit_sect_success = false; |
| |
| crit_sect_success = nrf_802154_critical_section_enter(); |
| |
| // If we managed to enter critical section, but there is already a pending event, |
| // it means that the Critical Section module is about to make one more iteration of the |
| // critical section exit procedure. To prevent race in continuous mode priorities notification, |
| // we do not notify directly, but just update the pending event. |
| if (crit_sect_success && rsch_pending_evt_is_none()) |
| { |
| nrf_802154_rsch_crit_sect_prio_changed(prio); |
| } |
| else |
| { |
| rsch_pending_evt_set(prio); |
| } |
| |
| if (crit_sect_success) |
| { |
| nrf_802154_critical_section_exit(); |
| } |
| } |
| |
| /*************************************************************************************************** |
| * @section Critical section callbacks |
| **************************************************************************************************/ |
| |
| void nrf_802154_critical_section_rsch_enter(void) |
| { |
| // Intentionally empty |
| } |
| |
| void nrf_802154_critical_section_rsch_exit(void) |
| { |
| rsch_evt_process(rsch_pending_evt_clear()); |
| } |
| |
| bool nrf_802154_critical_section_rsch_event_is_pending(void) |
| { |
| return !rsch_pending_evt_is_none(); |
| } |