hal_nordic/drivers/nrf_802154/driver/src/nrf_802154_critical_section.c

274 lines
8.2 KiB
C

/*
* Copyright (c) 2017 - 2021, Nordic Semiconductor ASA
* All rights reserved.
*
* SPDX-License-Identifier: BSD-3-Clause
*
* 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 used with requests by 802.15.4 driver.
*
*/
#define NRF_802154_MODULE_ID NRF_802154_DRV_MODULE_ID_CRITICAL_SECTION
#include "nrf_802154_critical_section.h"
#include <assert.h>
#include <stdint.h>
#include "nrf_802154_config.h"
#include "nrf_802154_debug.h"
#include "nrf_802154_utils.h"
#include "rsch/nrf_802154_rsch.h"
#include "platform/nrf_802154_lp_timer.h"
#include "platform/nrf_802154_irq.h"
#include <nrf.h>
#define CMSIS_IRQ_NUM_VECTACTIVE_DIFF 16
#define NESTED_CRITICAL_SECTION_ALLOWED_PRIORITY_NONE (-1)
static volatile uint8_t m_nested_critical_section_counter; ///< Counter of nested critical sections
static volatile int8_t m_nested_critical_section_allowed_priority; ///< Indicator if nested critical sections are currently allowed
/***************************************************************************************************
* @section Critical sections management
**************************************************************************************************/
/** @brief Enter critical section for RADIO peripheral
*
* @note RADIO peripheral registers (and NVIC) are modified only when timeslot is granted for the
* 802.15.4 driver.
*/
static void radio_critical_section_enter(void)
{
if (nrf_802154_rsch_prec_is_approved(RSCH_PREC_RAAL, RSCH_PRIO_MIN_APPROVED))
{
nrf_802154_irq_disable(RADIO_IRQn);
}
}
/** @brief Exit critical section for RADIO peripheral
*
* @note RADIO peripheral registers (and NVIC) are modified only when timeslot is granted for the
* 802.15.4 driver.
*/
static void radio_critical_section_exit(void)
{
if (nrf_802154_rsch_prec_is_approved(RSCH_PREC_RAAL, RSCH_PRIO_MIN_APPROVED))
{
nrf_802154_irq_enable(RADIO_IRQn);
}
}
/** @brief Convert active priority value to int8_t type.
*
* @param[in] active_priority Active priority in uint32_t format
*
* @return Active_priority value in int8_t format.
*/
static int8_t active_priority_convert(uint32_t active_priority)
{
return active_priority == UINT32_MAX ? INT8_MAX : (int8_t)active_priority;
}
/**@brief Returns priority of the currently executing context */
static int8_t active_vector_priority_get(void)
{
return active_priority_convert(nrf_802154_critical_section_active_vector_priority_get());
}
static bool critical_section_enter(bool forced)
{
bool result = false;
int8_t active_vector_priority;
nrf_802154_mcu_critical_state_t mcu_cs;
/* We assume that preempting interrupts won't change the priority
* of the currently executing one.
*/
active_vector_priority = active_vector_priority_get();
nrf_802154_mcu_critical_enter(mcu_cs);
if (forced ||
(m_nested_critical_section_counter == 0) ||
(m_nested_critical_section_allowed_priority == active_vector_priority))
{
uint8_t cnt = m_nested_critical_section_counter;
++cnt;
m_nested_critical_section_counter = cnt;
if (cnt == 1U)
{
nrf_802154_lp_timer_critical_section_enter();
radio_critical_section_enter();
}
result = true;
}
nrf_802154_mcu_critical_exit(mcu_cs);
return result;
}
static void critical_section_exit(void)
{
bool succeed = false;
do
{
uint8_t cnt;
nrf_802154_mcu_critical_state_t mcu_cs;
nrf_802154_mcu_critical_enter(mcu_cs);
cnt = m_nested_critical_section_counter;
assert(cnt > 0);
--cnt;
if (cnt == 0U)
{
if (nrf_802154_critical_section_rsch_event_is_pending())
{
nrf_802154_mcu_critical_exit(mcu_cs);
nrf_802154_critical_section_rsch_process_pending();
continue;
}
radio_critical_section_exit();
nrf_802154_lp_timer_critical_section_exit();
}
m_nested_critical_section_counter = cnt;
nrf_802154_mcu_critical_exit(mcu_cs);
succeed = true;
}
while (!succeed);
}
/***************************************************************************************************
* @section API functions
**************************************************************************************************/
void nrf_802154_critical_section_init(void)
{
m_nested_critical_section_counter = 0;
m_nested_critical_section_allowed_priority = NESTED_CRITICAL_SECTION_ALLOWED_PRIORITY_NONE;
}
bool nrf_802154_critical_section_enter(void)
{
bool result;
nrf_802154_log_function_enter(NRF_802154_LOG_VERBOSITY_LOW);
result = critical_section_enter(false);
nrf_802154_log_function_exit(NRF_802154_LOG_VERBOSITY_LOW);
return result;
}
void nrf_802154_critical_section_forcefully_enter(void)
{
bool critical_section_entered;
nrf_802154_log_function_enter(NRF_802154_LOG_VERBOSITY_LOW);
critical_section_entered = critical_section_enter(true);
assert(critical_section_entered);
(void)critical_section_entered;
nrf_802154_log_function_exit(NRF_802154_LOG_VERBOSITY_LOW);
}
void nrf_802154_critical_section_exit(void)
{
nrf_802154_log_function_enter(NRF_802154_LOG_VERBOSITY_LOW);
critical_section_exit();
nrf_802154_log_function_exit(NRF_802154_LOG_VERBOSITY_LOW);
}
void nrf_802154_critical_section_nesting_allow(void)
{
assert(m_nested_critical_section_allowed_priority ==
NESTED_CRITICAL_SECTION_ALLOWED_PRIORITY_NONE);
assert(m_nested_critical_section_counter >= 1);
m_nested_critical_section_allowed_priority = active_vector_priority_get();
}
void nrf_802154_critical_section_nesting_deny(void)
{
assert(m_nested_critical_section_allowed_priority >= 0);
assert(m_nested_critical_section_counter >= 1);
m_nested_critical_section_allowed_priority = NESTED_CRITICAL_SECTION_ALLOWED_PRIORITY_NONE;
}
bool nrf_802154_critical_section_is_nested(void)
{
return m_nested_critical_section_counter > 1;
}
uint32_t nrf_802154_critical_section_active_vector_priority_get(void)
{
uint32_t active_vector_id = (SCB->ICSR & SCB_ICSR_VECTACTIVE_Msk) >> SCB_ICSR_VECTACTIVE_Pos;
IRQn_Type irq_number;
uint32_t active_priority;
// Check if this function is called from main thread.
if (active_vector_id == 0)
{
return UINT32_MAX;
}
assert(active_vector_id >= CMSIS_IRQ_NUM_VECTACTIVE_DIFF);
irq_number = (IRQn_Type)(active_vector_id - CMSIS_IRQ_NUM_VECTACTIVE_DIFF);
active_priority = nrf_802154_irq_priority_get(irq_number);
return active_priority;
}