[PATCH v2 3/3] ARM: vf610: Add ARM Global Timer clocksource option

Stefan Agner stefan at agner.ch
Wed Sep 24 09:20:10 PDT 2014


Add the ARM Global Timer as clocksource/scheduler clock option and
use it as default scheduler clock. This leaves the PIT timer for
other users e.g. the secondary Cortex-M4 core. Also, the Global Timer
has double the precission (running at pheripheral clock compared to
IPG clock) and a 64-bit incrementing counter register. We still keep
the PIT timer as an secondary option in case the ARM Global Timer is
not available.

Signed-off-by: Stefan Agner <stefan at agner.ch>
---
 arch/arm/mach-imx/Kconfig | 19 ++++++++++++++++++-
 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/arch/arm/mach-imx/Kconfig b/arch/arm/mach-imx/Kconfig
index 11b2957..9482f58 100644
--- a/arch/arm/mach-imx/Kconfig
+++ b/arch/arm/mach-imx/Kconfig
@@ -633,12 +633,29 @@ config SOC_VF610
 	bool "Vybrid Family VF610 support"
 	select ARM_GIC
 	select PINCTRL_VF610
-	select VF_PIT_TIMER
 	select PL310_ERRATA_769419 if CACHE_L2X0
 
 	help
 	  This enable support for Freescale Vybrid VF610 processor.
 
+choice
+	prompt "Clocksource for scheduler clock"
+	depends on SOC_VF610
+	default ARM_GLOBAL_TIMER
+
+	config ARM_GLOBAL_TIMER
+		bool "Use ARM Global Timer"
+		select CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
+		help
+		  Use the ARM Global Timer as clocksource
+
+	config VF_PIT_TIMER
+		bool "Use PIT timer"
+		help
+		  Use SoC Periodic Interrupt Timer (PIT) as clocksource
+
+endchoice
+
 endif
 
 source "arch/arm/mach-imx/devices/Kconfig"
-- 
2.1.0




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