arch/arm64/kernel/idle.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Low-level idle sequences
   4  */
   5
   6 #include <linux/cpu.h>
   7 #include <linux/irqflags.h>
   8
   9 #include <asm/barrier.h>
  10 #include <asm/cpuidle.h>
  11 #include <asm/cpufeature.h>
  12 #include <asm/sysreg.h>
  13
  14 /*
  15  *      cpu_do_idle()
  16  *
  17  *      Idle the processor (wait for interrupt).
  18  *
  19  *      If the CPU supports priority masking we must do additional work to
  20  *      ensure that interrupts are not masked at the PMR (because the core will
  21  *      not wake up if we block the wake up signal in the interrupt controller).
  22  */
  23 void __cpuidle cpu_do_idle(void)
  24 {
  25         struct arm_cpuidle_irq_context context;
  26
  27         arm_cpuidle_save_irq_context(&context);
  28
  29         dsb(sy);
  30         wfi();
  31
  32         arm_cpuidle_restore_irq_context(&context);
  33 }
  34
  35 /*
  36  * This is our default idle handler.
  37  */
  38 void __cpuidle arch_cpu_idle(void)
  39 {
  40         /*
  41          * This should do all the clock switching and wait for interrupt
  42          * tricks
  43          */
  44         cpu_do_idle();
  45 }