[PATCH v2] irqchip/apple-aic: Only handle PMC interrupt as FIQ when configured to fire FIQ

[Nick Chan <towinchenmi@gmail.com>]

The CPU PMU in Apple SoCs can be configured to fire its interrupt in one
of several ways, and since Apple A11 one of the method is FIQ. Only handle
the PMC interrupt as a FIQ when the CPU PMU has been configured to fire
FIQs.

Cc: stable@vger.kernel.org
Fixes: c7708816c944 ("irqchip/apple-aic: Wire PMU interrupts")
Signed-off-by: Nick Chan <towinchenmi@gmail.com>
---

Changes in v2:
Fix the conditional to have the intented behavior of evaluating to true
only when both PMCR0_IMODE is PMCR0_IMODE_FIQ and PMCR0_IACT is set by
reverting the conditional to how it is before c7708816c944.

Link to v1: https://lore.kernel.org/asahi/20250117170227.45243-1-towinchenmi@gmail.com/T

- Nick Chan


 drivers/irqchip/irq-apple-aic.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/irqchip/irq-apple-aic.c b/drivers/irqchip/irq-apple-aic.c
index da5250f0155c..2b1684c60e3c 100644
--- a/drivers/irqchip/irq-apple-aic.c
+++ b/drivers/irqchip/irq-apple-aic.c
@@ -577,7 +577,8 @@ static void __exception_irq_entry aic_handle_fiq(struct pt_regs *regs)
 						  AIC_FIQ_HWIRQ(AIC_TMR_EL02_VIRT));
 	}
 
-	if (read_sysreg_s(SYS_IMP_APL_PMCR0_EL1) & PMCR0_IACT) {
+	if ((read_sysreg_s(SYS_IMP_APL_PMCR0_EL1) & (PMCR0_IMODE | PMCR0_IACT)) ==
+			(FIELD_PREP(PMCR0_IMODE, PMCR0_IMODE_FIQ) | PMCR0_IACT)) {
 		int irq;
 		if (cpumask_test_cpu(smp_processor_id(),
 				     &aic_irqc->fiq_aff[AIC_CPU_PMU_P]->aff))

base-commit: 40384c840ea1944d7c5a392e8975ed088ecf0b37
-- 
2.48.1