irqchip/bcm2836: Convert to hotplug state machine

Install the callbacks via the state machine.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Acked-by: Jason Cooper <jason@lakedaemon.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Marc Zyngier <marc.zyngier@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153333.416260485@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>

drivers/irqchip/irq-bcm2836.c

@@ -202,26 +202,19 @@ static void bcm2836_arm_irqchip_send_ipi(const struct cpumask *mask,
 	}
 }
 
-/* Unmasks the IPI on the CPU when it's online. */
-static int bcm2836_arm_irqchip_cpu_notify(struct notifier_block *nfb,
-					  unsigned long action, void *hcpu)
+static int bcm2836_cpu_starting(unsigned int cpu)
 {
-	unsigned int cpu = (unsigned long)hcpu;
-	unsigned int int_reg = LOCAL_MAILBOX_INT_CONTROL0;
-	unsigned int mailbox = 0;
-
-	if (action == CPU_STARTING || action == CPU_STARTING_FROZEN)
-		bcm2836_arm_irqchip_unmask_per_cpu_irq(int_reg, mailbox, cpu);
-	else if (action == CPU_DYING)
-		bcm2836_arm_irqchip_mask_per_cpu_irq(int_reg, mailbox, cpu);
-
-	return NOTIFY_OK;
+	bcm2836_arm_irqchip_unmask_per_cpu_irq(LOCAL_MAILBOX_INT_CONTROL0, 0,
+					       cpu);
+	return 0;
 }
 
-static struct notifier_block bcm2836_arm_irqchip_cpu_notifier = {
-	.notifier_call = bcm2836_arm_irqchip_cpu_notify,
-	.priority = 100,
-};
+static int bcm2836_cpu_dying(unsigned int cpu)
+{
+	bcm2836_arm_irqchip_mask_per_cpu_irq(LOCAL_MAILBOX_INT_CONTROL0, 0,
+					     cpu);
+	return 0;
+}
 
 #ifdef CONFIG_ARM
 int __init bcm2836_smp_boot_secondary(unsigned int cpu,
@@ -251,10 +244,9 @@ bcm2836_arm_irqchip_smp_init(void)
 {
 #ifdef CONFIG_SMP
 	/* Unmask IPIs to the boot CPU. */
-	bcm2836_arm_irqchip_cpu_notify(&bcm2836_arm_irqchip_cpu_notifier,
-				       CPU_STARTING,
-				       (void *)(uintptr_t)smp_processor_id());
-	register_cpu_notifier(&bcm2836_arm_irqchip_cpu_notifier);
+	cpuhp_setup_state(CPUHP_AP_IRQ_BCM2836_STARTING,
+			  "AP_IRQ_BCM2836_STARTING", bcm2836_cpu_starting,
+			  bcm2836_cpu_dying);
 
 	set_smp_cross_call(bcm2836_arm_irqchip_send_ipi);
 

include/linux/cpuhotplug.h

@@ -14,6 +14,7 @@ enum cpuhp_state {
 	CPUHP_AP_IRQ_HIP04_STARTING,
 	CPUHP_AP_IRQ_ARMADA_XP_STARTING,
 	CPUHP_AP_IRQ_ARMADA_CASC_STARTING,
+	CPUHP_AP_IRQ_BCM2836_STARTING,
 	CPUHP_AP_NOTIFY_STARTING,
 	CPUHP_AP_ONLINE,
 	CPUHP_TEARDOWN_CPU,