interrupt_sam_nvic.c

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/*
 * Support and FAQ: visit <a href="https://www.microchip.com/support/">Microchip 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();
        }
}