irqchip/apple-aic: Drop support for custom PMU irq partitions

Similarly to what has been done for GICv3, drop the irq partitioning
support from the AIC driver, effectively merging the two per-cpu interrupts
for the PMU.

Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Will Deacon <will@kernel.org>
Reviewed-by: Sven Peter <sven@kernel.org>
Link: https://patch.msgid.link/20251020122944.3074811-23-maz@kernel.org

Author: Marc Zyngier

drivers/irqchip/irq-apple-aic.c

@@ -578,16 +578,9 @@ static void __exception_irq_entry aic_handle_fiq(struct pt_regs *regs)
 	}
 
 	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))
-			irq = AIC_CPU_PMU_P;
-		else
-			irq = AIC_CPU_PMU_E;
+			(FIELD_PREP(PMCR0_IMODE, PMCR0_IMODE_FIQ) | PMCR0_IACT))
 		generic_handle_domain_irq(aic_irqc->hw_domain,
-					  AIC_FIQ_HWIRQ(irq));
-	}
+					  AIC_FIQ_HWIRQ(AIC_CPU_PMU_P));
 
 	if (static_branch_likely(&use_fast_ipi) &&
 	    (FIELD_GET(UPMCR0_IMODE, read_sysreg_s(SYS_IMP_APL_UPMCR0_EL1)) == UPMCR0_IMODE_FIQ) &&
@@ -632,18 +625,7 @@ static int aic_irq_domain_map(struct irq_domain *id, unsigned int irq,
 				    handle_fasteoi_irq, NULL, NULL);
 		irqd_set_single_target(irq_desc_get_irq_data(irq_to_desc(irq)));
 	} else {
-		int fiq = FIELD_GET(AIC_EVENT_NUM, hw);
-
-		switch (fiq) {
-		case AIC_CPU_PMU_P:
-		case AIC_CPU_PMU_E:
-			irq_set_percpu_devid_partition(irq, &ic->fiq_aff[fiq]->aff);
-			break;
-		default:
-			irq_set_percpu_devid(irq);
-			break;
-		}
-
+		irq_set_percpu_devid(irq);
 		irq_domain_set_info(id, irq, hw, &fiq_chip, id->host_data,
 				    handle_percpu_devid_irq, NULL, NULL);
 	}
@@ -732,6 +714,10 @@ static int aic_irq_domain_translate(struct irq_domain *id,
 				break;
 			}
 		}
+
+		/* Merge the two PMUs on a single interrupt */
+		if (*hwirq == AIC_CPU_PMU_E)
+			*hwirq = AIC_CPU_PMU_P;
 		break;
 	default:
 		return -EINVAL;