ARM: perf_event: allow platform-specific interrupt handler

Allow a platform-specific IRQ handler to be specified via platform data.
This will be used to implement the single-irq workaround for the DB8500.

Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

2 files changed, 30 insertions, 1 deletions

diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h
index 8ccea012722c..7544ce6b481a 100644
--- a/arch/arm/include/asm/pmu.h
+++ b/arch/arm/include/asm/pmu.h
@@ -12,11 +12,25 @@
 #ifndef __ARM_PMU_H__
 #define __ARM_PMU_H__
 
+#include <linux/interrupt.h>
+
 enum arm_pmu_type {
         ARM_PMU_DEVICE_CPU      = 0,
         ARM_NUM_PMU_DEVICES,
 };
 
+/*
+ * struct arm_pmu_platdata - ARM PMU platform data
+ *
+ * @handle_irq: an optional handler which will be called from the interrupt and
+ * passed the address of the low level handler, and can be used to implement
+ * any platform specific handling before or after calling it.
+ */
+struct arm_pmu_platdata {
+        irqreturn_t (*handle_irq)(int irq, void *dev,
+                                  irq_handler_t pmu_handler);
+};
+
 #ifdef CONFIG_CPU_HAS_PMU
 
 /**
diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c
index 5efa2647a2fb..323951191283 100644
--- a/arch/arm/kernel/perf_event.c
+++ b/arch/arm/kernel/perf_event.c
@@ -377,9 +377,18 @@ validate_group(struct perf_event *event)
         return 0;
 }
 
+static irqreturn_t armpmu_platform_irq(int irq, void *dev)
+{
+        struct arm_pmu_platdata *plat = dev_get_platdata(&pmu_device->dev);
+
+        return plat->handle_irq(irq, dev, armpmu->handle_irq);
+}
+
 static int
 armpmu_reserve_hardware(void)
 {
+        struct arm_pmu_platdata *plat;
+        irq_handler_t handle_irq;
         int i, err = -ENODEV, irq;
 
         pmu_device = reserve_pmu(ARM_PMU_DEVICE_CPU);
@@ -390,6 +399,12 @@ armpmu_reserve_hardware(void)
 
         init_pmu(ARM_PMU_DEVICE_CPU);
 
+        plat = dev_get_platdata(&pmu_device->dev);
+        if (plat && plat->handle_irq)
+                handle_irq = armpmu_platform_irq;
+        else
+                handle_irq = armpmu->handle_irq;
+
         if (pmu_device->num_resources < 1) {
                 pr_err("no irqs for PMUs defined\n");
                 return -ENODEV;
@@ -400,7 +415,7 @@ armpmu_reserve_hardware(void)
                 if (irq < 0)
                         continue;
 
-                err = request_irq(irq, armpmu->handle_irq,
+                err = request_irq(irq, handle_irq,
                                   IRQF_DISABLED | IRQF_NOBALANCING,
                                   "armpmu", NULL);
                 if (err) {