arm64: arch_timer: Implement support for interrupt-names

This allows the devicetree to correctly represent the available set of
timers, which varies from device to device, without the need for fake
dummy interrupts for unavailable slots.

Also add the hyp-virt timer/PPI, which is not currently used, but worth
representing.
Reviewed-by: Tony Lindgren <tony@atomide.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Reviewed-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Hector Martin <marcan@marcan.st>

drivers/clocksource/arm_arch_timer.c

@@ -63,6 +63,14 @@ struct arch_timer {
 static u32 arch_timer_rate;
 static int arch_timer_ppi[ARCH_TIMER_MAX_TIMER_PPI];
 
+static const char *arch_timer_ppi_names[ARCH_TIMER_MAX_TIMER_PPI] = {
+	[ARCH_TIMER_PHYS_SECURE_PPI]	= "sec-phys",
+	[ARCH_TIMER_PHYS_NONSECURE_PPI]	= "phys",
+	[ARCH_TIMER_VIRT_PPI]		= "virt",
+	[ARCH_TIMER_HYP_PPI]		= "hyp-phys",
+	[ARCH_TIMER_HYP_VIRT_PPI]	= "hyp-virt",
+};
+
 static struct clock_event_device __percpu *arch_timer_evt;
 
 static enum arch_timer_ppi_nr arch_timer_uses_ppi = ARCH_TIMER_VIRT_PPI;
@@ -1280,8 +1288,9 @@ static void __init arch_timer_populate_kvm_info(void)
 
 static int __init arch_timer_of_init(struct device_node *np)
 {
-	int i, ret;
+	int i, irq, ret;
 	u32 rate;
+	bool has_names;
 
 	if (arch_timers_present & ARCH_TIMER_TYPE_CP15) {
 		pr_warn("multiple nodes in dt, skipping\n");
@@ -1289,8 +1298,17 @@ static int __init arch_timer_of_init(struct device_node *np)
 	}
 
 	arch_timers_present |= ARCH_TIMER_TYPE_CP15;
-	for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++)
-		arch_timer_ppi[i] = irq_of_parse_and_map(np, i);
+
+	has_names = of_property_read_bool(np, "interrupt-names");
+
+	for (i = ARCH_TIMER_PHYS_SECURE_PPI; i < ARCH_TIMER_MAX_TIMER_PPI; i++) {
+		if (has_names)
+			irq = of_irq_get_byname(np, arch_timer_ppi_names[i]);
+		else
+			irq = of_irq_get(np, i);
+		if (irq > 0)
+			arch_timer_ppi[i] = irq;
+	}
 
 	arch_timer_populate_kvm_info();
 

include/clocksource/arm_arch_timer.h

@@ -32,6 +32,7 @@ enum arch_timer_ppi_nr {
 	ARCH_TIMER_PHYS_NONSECURE_PPI,
 	ARCH_TIMER_VIRT_PPI,
 	ARCH_TIMER_HYP_PPI,
+	ARCH_TIMER_HYP_VIRT_PPI,
 	ARCH_TIMER_MAX_TIMER_PPI
 };