[PATCH v2 3/4] PSCI: Use cpuidle context helpers in psci_cpu_suspend_enter()

[Marc Zyngier]

The PSCI CPU suspend code isn't aware of the PMR vs DAIF game,
resulting in a system that locks up if entering CPU suspend
with GICv3 pNMI enabled.

To save the day, teach the suspend code about our new cpuidle
context helpers, which will do everything that's required just
like the usual WFI cpuidle code.

This fixes my Altra system, which would otherwise lock-up at
boot time when booted with irqchip.gicv3_pseudo_nmi=1.

Tested-by: Valentin Schneider <valentin.schneider at arm.com>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi at arm.com>
Signed-off-by: Marc Zyngier <maz at kernel.org>
---
 drivers/firmware/psci/psci.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c
index 3c1c5daf6df2..e3da38e15c5b 100644
--- a/drivers/firmware/psci/psci.c
+++ b/drivers/firmware/psci/psci.c
@@ -335,10 +335,15 @@ int psci_cpu_suspend_enter(u32 state)
 {
 	int ret;
 
-	if (!psci_power_state_loses_context(state))
+	if (!psci_power_state_loses_context(state)) {
+		struct arm_cpuidle_irq_context context;
+
+		arm_cpuidle_save_irq_context(&context);
 		ret = psci_ops.cpu_suspend(state, 0);
-	else
+		arm_cpuidle_restore_irq_context(&context);
+	} else {
 		ret = cpu_suspend(state, psci_suspend_finisher);
+	}
 
 	return ret;
 }
-- 
2.30.2