bus: ARM CCN PMU driver

Driver providing perf backend for ARM Cache Coherent Network
interconnect. Supports counting all hardware events and crosspoint
watchpoints.

Currently works with CCN-504 only, although there should be
no changes required for CCN-508 (just impossible to test it now).

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/drivers/bus/Kconfig b/drivers/bus/Kconfig
index 1f37d98..5c0c276 100644
--- a/drivers/bus/Kconfig
+++ b/drivers/bus/Kconfig
@@ -50,6 +50,13 @@
 	  Driver supporting the CCI cache coherent interconnect for ARM
 	  platforms.
 
+config ARM_CCN
+	bool "ARM CCN driver support"
+	depends on ARM || ARM64
+	help
+	  PMU (perf) driver supporting the ARM CCN (Cache Coherent Network)
+	  interconnect.
+
 config VEXPRESS_CONFIG
 	bool "Versatile Express configuration bus"
 	default y if ARCH_VEXPRESS