irqchip: gic: Simplify gic_configure_irq by using IRQCHIP_SET_TYPE_MASKED

GIC requires to disable the interrupt before changing the trigger type.
irqchip core provides IRQCHIP_SET_TYPE_MASKED flag and ensures that the
interrupt is masked before calling chip.irq_set_type() if the irqchip
sets the flag.

This patch adds IRQCHIP_SET_TYPE_MASKED to GIC irqchip so that the core
can manage disabling the interrupt while changing the trigger type.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Jason Cooper <jason@lakedaemon.net>
Link: http://lkml.kernel.org/r/1433501997-19205-1-git-send-email-sudeep.holla@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

drivers/irqchip/irq-gic-common.c

@@ -24,11 +24,8 @@
 int gic_configure_irq(unsigned int irq, unsigned int type,
 		       void __iomem *base, void (*sync_access)(void))
 {
-	u32 enablemask = 1 << (irq % 32);
-	u32 enableoff = (irq / 32) * 4;
 	u32 confmask = 0x2 << ((irq % 16) * 2);
 	u32 confoff = (irq / 16) * 4;
-	bool enabled = false;
 	u32 val, oldval;
 	int ret = 0;
 
@@ -42,17 +39,6 @@ int gic_configure_irq(unsigned int irq, unsigned int type,
 	else if (type & IRQ_TYPE_EDGE_BOTH)
 		val |= confmask;
 
-	/*
-	 * As recommended by the spec, disable the interrupt before changing
-	 * the configuration
-	 */
-	if (readl_relaxed(base + GIC_DIST_ENABLE_SET + enableoff) & enablemask) {
-		writel_relaxed(enablemask, base + GIC_DIST_ENABLE_CLEAR + enableoff);
-		if (sync_access)
-			sync_access();
-		enabled = true;
-	}
-
 	/*
 	 * Write back the new configuration, and possibly re-enable
 	 * the interrupt. If we tried to write a new configuration and failed,
@@ -62,9 +48,6 @@ int gic_configure_irq(unsigned int irq, unsigned int type,
 	if (readl_relaxed(base + GIC_DIST_CONFIG + confoff) != val && val != oldval)
 		ret = -EINVAL;
 
-	if (enabled)
-		writel_relaxed(enablemask, base + GIC_DIST_ENABLE_SET + enableoff);
-
 	if (sync_access)
 		sync_access();
 

drivers/irqchip/irq-gic-v3.c

@@ -658,6 +658,7 @@ static struct irq_chip gic_chip = {
 	.irq_set_affinity	= gic_set_affinity,
 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
+	.flags			= IRQCHIP_SET_TYPE_MASKED,
 };
 
 #define GIC_ID_NR		(1U << gic_data.rdists.id_bits)

drivers/irqchip/irq-gic.c

@@ -324,6 +324,7 @@ static struct irq_chip gic_chip = {
 #endif
 	.irq_get_irqchip_state	= gic_irq_get_irqchip_state,
 	.irq_set_irqchip_state	= gic_irq_set_irqchip_state,
+	.flags			= IRQCHIP_SET_TYPE_MASKED,
 };
 
 void __init gic_cascade_irq(unsigned int gic_nr, unsigned int irq)

drivers/irqchip/irq-hip04.c

@@ -202,6 +202,7 @@ static struct irq_chip hip04_irq_chip = {
 #ifdef CONFIG_SMP
 	.irq_set_affinity	= hip04_irq_set_affinity,
 #endif
+	.flags			= IRQCHIP_SET_TYPE_MASKED,
 };
 
 static u16 hip04_get_cpumask(struct hip04_irq_data *intc)