ARM: 5902/4: arm/perfevents: implement perf event support for ARMv6

This patch implements support for ARMv6 performance counters in the
Linux performance events subsystem. ARMv6 architectures that have the
performance counters should enable HW_PERF_EVENTS to get hardware
performance events support in addition to the software events.

Note: only ARM Ltd ARM cores are supported.

This implementation also provides an ARM PMU abstraction layer to allow
ARMv7 and others to be supported in the future by adding new a
'struct arm_pmu'.

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

1 files changed, 8 insertions, 0 deletions

diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index 74d1e767f0b7..9fb91ce106bc 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -1174,6 +1174,14 @@ config HIGHPTE
         depends on HIGHMEM
         depends on !OUTER_CACHE
 
+config HW_PERF_EVENTS
+        bool "Enable hardware performance counter support for perf events"
+        depends on PERF_EVENTS && CPU_HAS_PMU && CPU_V6
+        default y
+        help
+          Enable hardware performance counter support for perf events. If
+          disabled, perf events will use software events only.
+
 source "mm/Kconfig"
 
 config LEDS