[PATCH v4 4/6] ARM: at91: Implement clocksource selection

Alexandre Belloni alexandre.belloni at bootlin.com
Wed Apr 18 03:51:41 PDT 2018


Allow selecting and unselecting the PIT clocksource driver so it doesn't
have to be compile when unused.

Tested-by: Alexander Dahl <ada at thorsis.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni at bootlin.com>
---
 arch/arm/mach-at91/Kconfig | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 1254bf9d91b4..64f18cd220b9 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -106,6 +106,31 @@ config SOC_AT91SAM9
 	    AT91SAM9X35
 	    AT91SAM9XE
 
+comment "Clocksource driver selection"
+
+config ATMEL_CLOCKSOURCE_PIT
+	bool "Periodic Interval Timer (PIT) support"
+	depends on SOC_AT91SAM9 || SOC_SAMA5
+	default SOC_AT91SAM9 || SOC_SAMA5
+	select ATMEL_PIT
+	help
+	  Select this to get a clocksource based on the Atmel Periodic Interval
+	  Timer. It has a relatively low resolution and the TC Block clocksource
+	  should be preferred.
+
+config ATMEL_CLOCKSOURCE_TCB
+	bool "Timer Counter Blocks (TCB) support"
+	depends on SOC_AT91RM9200 || SOC_AT91SAM9 || SOC_SAMA5 || COMPILE_TEST
+	default SOC_AT91RM9200 || SOC_AT91SAM9 || SOC_SAMA5
+	depends on !ATMEL_TCLIB
+	select ATMEL_ARM_TCB_CLKSRC
+	help
+	  Select this to get a high precision clocksource based on a
+	  TC block with a 5+ MHz base clock rate.
+	  On platforms with 16-bit counters, two timer channels are combined
+	  to make a single 32-bit timer.
+	  It can also be used as a clock event device supporting oneshot mode.
+
 config HAVE_AT91_UTMI
 	bool
 
-- 
2.17.0




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