clocksource: add DBX500 PRCMU Timer support

This patch adds the DBX500 PRCMU Timer driver as a clocksource
and as sched_clock.

Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Mattias Wallin <mattias.wallin@stericsson.com>
Signed-off-by: Jonas Aaberg <jonas.aberg@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index 34e9c4f..999d6a0 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -15,3 +15,18 @@
 
 config DW_APB_TIMER
 	bool
+
+config CLKSRC_DBX500_PRCMU
+	bool "Clocksource PRCMU Timer"
+	depends on UX500_SOC_DB5500 || UX500_SOC_DB8500
+	default y
+	help
+	  Use the always on PRCMU Timer as clocksource
+
+config CLKSRC_DBX500_PRCMU_SCHED_CLOCK
+	bool "Clocksource PRCMU Timer sched_clock"
+	depends on (CLKSRC_DBX500_PRCMU && !NOMADIK_MTU_SCHED_CLOCK)
+	select HAVE_SCHED_CLOCK
+	default y
+	help
+	  Use the always on PRCMU Timer as sched_clock