/** | |
* \file | |
* | |
* \brief Global interrupt management for SAM D20, SAM3 and SAM4 (NVIC based) | |
* | |
* Copyright (c) 2012-2015 Atmel Corporation. All rights reserved. | |
* | |
* \asf_license_start | |
* | |
* \page License | |
* | |
* 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. The name of Atmel may not be used to endorse or promote products derived | |
* from this software without specific prior written permission. | |
* | |
* 4. This software may only be redistributed and used in connection with an | |
* Atmel microcontroller product. | |
* | |
* THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED | |
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF | |
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*/ | |
/* | |
* Support and FAQ: visit <a href="http://www.atmel.com/design-support/">Atmel Support</a> | |
*/ | |
#include "interrupt_sam_nvic.h" | |
#if !defined(__DOXYGEN__) | |
/* Deprecated - global flag to determine the global interrupt state. Required by | |
* QTouch library, however new applications should use cpu_irq_is_enabled() | |
* which probes the true global interrupt state from the CPU special registers. | |
*/ | |
volatile bool g_interrupt_enabled = true; | |
#endif | |
void cpu_irq_enter_critical(void) | |
{ | |
if (cpu_irq_critical_section_counter == 0) { | |
if (cpu_irq_is_enabled()) { | |
cpu_irq_disable(); | |
cpu_irq_prev_interrupt_state = true; | |
} else { | |
/* Make sure the to save the prev state as false */ | |
cpu_irq_prev_interrupt_state = false; | |
} | |
} | |
cpu_irq_critical_section_counter++; | |
} | |
void cpu_irq_leave_critical(void) | |
{ | |
/* Check if the user is trying to leave a critical section when not in a critical section */ | |
Assert(cpu_irq_critical_section_counter > 0); | |
cpu_irq_critical_section_counter--; | |
/* Only enable global interrupts when the counter reaches 0 and the state of the global interrupt flag | |
was enabled when entering critical state */ | |
if ((cpu_irq_critical_section_counter == 0) && (cpu_irq_prev_interrupt_state)) { | |
cpu_irq_enable(); | |
} | |
} | |