mirror of https://github.com/ARMmbed/mbed-os.git
68 lines
1.7 KiB
C
68 lines
1.7 KiB
C
/* mbed Microcontroller Library
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* Copyright (c) 2017 ARM Limited
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include "cmsis.h"
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#include "hal/critical_section_api.h"
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#include "platform/mbed_assert.h"
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#include "platform/mbed_toolchain.h"
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#include <stdbool.h>
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static volatile bool critical_interrupts_enabled = false;
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static volatile bool state_saved = false;
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static bool are_interrupts_enabled(void)
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{
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#if defined(__CORTEX_A9)
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return ((__get_CPSR() & 0x80) == 0);
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#else
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return ((__get_PRIMASK() & 0x1) == 0);
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#endif
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}
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MBED_WEAK void hal_critical_section_enter(void)
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{
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const bool interrupt_state = are_interrupts_enabled();
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__disable_irq();
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if (state_saved == true) {
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return;
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}
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critical_interrupts_enabled = interrupt_state;
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state_saved = true;
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}
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MBED_WEAK void hal_critical_section_exit(void)
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{
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#ifndef FEATURE_UVISOR
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// Interrupts must be disabled on invoking an exit from a critical section
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MBED_ASSERT(!are_interrupts_enabled());
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#endif
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state_saved = false;
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// Restore the IRQs to their state prior to entering the critical section
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if (critical_interrupts_enabled == true) {
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__enable_irq();
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}
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}
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MBED_WEAK bool hal_in_critical_section(void)
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{
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return (state_saved == true);
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}
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