clocksource: Add generic dummy timer driver
Several architectures have a dummy timer driver tightly coupled with
their broadcast code to support machines without cpu-local timers (or
where there is a lack of driver support).
Since 12ad100046: "clockevents: Add generic timer broadcast function"
it's been possible to write broadcast-capable timer drivers decoupled
from the broadcast mechanism. We can use this functionality to implement
a generic dummy timer driver that can be shared by all architectures
with generic tick broadcast (ARCH_HAS_TICK_BROADCAST).
This patch implements a generic dummy timer using this facility.
[sboyd: Make percpu data static, use __this_cpu_ptr(), move to
early_initcall to properly register on each CPU, only
register if more than one CPU possible]
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>,
Cc: John Stultz <john.stultz@linaro.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1370291642-13259-3-git-send-email-sboyd@codeaurora.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile
index 4853ea0..9ba8b4d 100644
--- a/drivers/clocksource/Makefile
+++ b/drivers/clocksource/Makefile
@@ -31,3 +31,4 @@
obj-$(CONFIG_ARM_ARCH_TIMER) += arm_arch_timer.o
obj-$(CONFIG_CLKSRC_METAG_GENERIC) += metag_generic.o
+obj-$(CONFIG_ARCH_HAS_TICK_BROADCAST) += dummy_timer.o