[tip: irq/urgent] irqchip/gic-v3: Handle CPU_PM_ENTER_FAILED correctly

From: tip-bot2 for Yogesh Lal
Date: Wed Jan 15 2025 - 04:17:40 EST


The following commit has been merged into the irq/urgent branch of tip:

Commit-ID: 0d62a49ab55c99e8deb4593b8d9f923de1ab5c18
Gitweb: https://git.kernel.org/tip/0d62a49ab55c99e8deb4593b8d9f923de1ab5c18
Author: Yogesh Lal <quic_ylal@xxxxxxxxxxx>
AuthorDate: Fri, 20 Dec 2024 15:09:07 +05:30
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitterDate: Wed, 15 Jan 2025 09:42:44 +01:00

irqchip/gic-v3: Handle CPU_PM_ENTER_FAILED correctly

When a CPU attempts to enter low power mode, it disables the redistributor
and Group 1 interrupts and reinitializes the system registers upon wakeup.

If the transition into low power mode fails, then the CPU_PM framework
invokes the PM notifier callback with CPU_PM_ENTER_FAILED to allow the
drivers to undo the state changes.

The GIC V3 driver ignores CPU_PM_ENTER_FAILED, which leaves the GIC in
disabled state.

Handle CPU_PM_ENTER_FAILED in the same way as CPU_PM_EXIT to restore normal
operation.

[ tglx: Massage change log, add Fixes tag ]

Fixes: 3708d52fc6bb ("irqchip: gic-v3: Implement CPU PM notifier")
Signed-off-by: Yogesh Lal <quic_ylal@xxxxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Acked-by: Marc Zyngier <maz@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Link: https://lore.kernel.org/all/20241220093907.2747601-1-quic_ylal@xxxxxxxxxxx
---
drivers/irqchip/irq-gic-v3.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 79d8cc8..76dce0a 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -1522,7 +1522,7 @@ static int gic_retrigger(struct irq_data *data)
static int gic_cpu_pm_notifier(struct notifier_block *self,
unsigned long cmd, void *v)
{
- if (cmd == CPU_PM_EXIT) {
+ if (cmd == CPU_PM_EXIT || cmd == CPU_PM_ENTER_FAILED) {
if (gic_dist_security_disabled())
gic_enable_redist(true);
gic_cpu_sys_reg_enable();