static inline int ux500_enter_idle()

in cpuidle-ux500.c [23:89]


static inline int ux500_enter_idle(struct cpuidle_device *dev,
				   struct cpuidle_driver *drv, int index)
{
	int this_cpu = smp_processor_id();
	bool recouple = false;

	if (atomic_inc_return(&master) == num_online_cpus()) {

		/* With this lock, we prevent the other cpu to exit and enter
		 * this function again and become the master */
		if (!spin_trylock(&master_lock))
			goto wfi;

		/* decouple the gic from the A9 cores */
		if (prcmu_gic_decouple()) {
			spin_unlock(&master_lock);
			goto out;
		}

		/* If an error occur, we will have to recouple the gic
		 * manually */
		recouple = true;

		/* At this state, as the gic is decoupled, if the other
		 * cpu is in WFI, we have the guarantee it won't be wake
		 * up, so we can safely go to retention */
		if (!prcmu_is_cpu_in_wfi(this_cpu ? 0 : 1))
			goto out;

		/* The prcmu will be in charge of watching the interrupts
		 * and wake up the cpus */
		if (prcmu_copy_gic_settings())
			goto out;

		/* Check in the meantime an interrupt did
		 * not occur on the gic ... */
		if (prcmu_gic_pending_irq())
			goto out;

		/* ... and the prcmu */
		if (prcmu_pending_irq())
			goto out;

		/* Go to the retention state, the prcmu will wait for the
		 * cpu to go WFI and this is what happens after exiting this
		 * 'master' critical section */
		if (prcmu_set_power_state(PRCMU_AP_IDLE, true, true))
			goto out;

		/* When we switch to retention, the prcmu is in charge
		 * of recoupling the gic automatically */
		recouple = false;

		spin_unlock(&master_lock);
	}
wfi:
	cpu_do_idle();
out:
	atomic_dec(&master);

	if (recouple) {
		prcmu_gic_recouple();
		spin_unlock(&master_lock);
	}

	return index;
}