ARM: 6064/1: pmu: register IRQs at runtime

The current PMU infrastructure for ARM requires that the IRQs for the PMU
device are fixed at compile time and are selected based on the ARCH_ or MACH_ flags. This has the disadvantage of tying the Kernel down to a
particular board as far as profiling is concerned.

This patch replaces the compile-time IRQ registration with a runtime mechanism which allows the IRQs to be registered with the framework as
a platform_device.

A further advantage of this change is that there is scope for registering
different types of performance counters in the future by changing the id
of the platform_device and attaching different resources to it.

Acked-by: Jamie Iles <jamie.iles@picochip.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 12 insertions, 15 deletions

diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h
index 44bec1f..8ccea01 100644
--- a/arch/arm/include/asm/pmu.h
+++ b/arch/arm/include/asm/pmu.h
@@ -19,31 +19,26 @@ enum arm_pmu_type {
 
 #ifdef CONFIG_CPU_HAS_PMU
 
-struct pmu_irqs {
-	const int   *irqs;
-	int	    num_irqs;
-};
-
 /**
  * reserve_pmu() - reserve the hardware performance counters
  *
  * Reserve the hardware performance counters in the system for exclusive use.
- * The 'struct pmu_irqs' for the system is returned on success, ERR_PTR()
+ * The platform_device for the system is returned on success, ERR_PTR()
  * encoded error on failure.
  */
-extern const struct pmu_irqs *
-reserve_pmu(void);
+extern struct platform_device *
+reserve_pmu(enum arm_pmu_type device);
 
 /**
  * release_pmu() - Relinquish control of the performance counters
  *
  * Release the performance counters and allow someone else to use them.
  * Callers must have disabled the counters and released IRQs before calling
- * this. The 'struct pmu_irqs' returned from reserve_pmu() must be passed as
+ * this. The platform_device returned from reserve_pmu() must be passed as
  * a cookie.
  */
 extern int
-release_pmu(const struct pmu_irqs *irqs);
+release_pmu(struct platform_device *pdev);
 
 /**
  * init_pmu() - Initialise the PMU.
@@ -53,24 +48,26 @@ release_pmu(const struct pmu_irqs *irqs);
  * the actual hardware initialisation.
  */
 extern int
-init_pmu(void);
+init_pmu(enum arm_pmu_type device);
 
 #else /* CONFIG_CPU_HAS_PMU */
 
-static inline const struct pmu_irqs *
-reserve_pmu(void)
+#include <linux/err.h>
+
+static inline struct platform_device *
+reserve_pmu(enum arm_pmu_type device)
 {
 	return ERR_PTR(-ENODEV);
 }
 
 static inline int
-release_pmu(const struct pmu_irqs *irqs)
+release_pmu(struct platform_device *pdev)
 {
 	return -ENODEV;
 }
 
 static inline int
-init_pmu(void)
+init_pmu(enum arm_pmu_type device)
 {
 	return -ENODEV;
 }