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authorStephen Boyd <sboyd@codeaurora.org>2013-07-18 16:21:18 -0700
committerJohn Stultz <john.stultz@linaro.org>2013-10-09 16:54:10 -0700
commit65cd4f6c99c1170bd0114dbd71b978012ea44d28 (patch)
treefbde89149eb5032b49875cddf728d598ffd349ad /drivers/clocksource
parent07783397c6e3757de805bda5e1139a9e47aa7d74 (diff)
downloadblackbird-op-linux-65cd4f6c99c1170bd0114dbd71b978012ea44d28.tar.gz
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arch_timer: Move to generic sched_clock framework
Register with the generic sched_clock framework now that it supports 64 bits. This fixes two problems with the current sched_clock support for machines using the architected timers. First off, we don't subtract the start value from subsequent sched_clock calls so we can potentially start off with sched_clock returning gigantic numbers. Second, there is no support for suspend/resume handling so problems such as discussed in 6a4dae5 (ARM: 7565/1: sched: stop sched_clock() during suspend, 2012-10-23) can happen without this patch. Finally, it allows us to move the sched_clock setup into drivers clocksource out of the arch ports. Cc: Christopher Covington <cov@codeaurora.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Signed-off-by: John Stultz <john.stultz@linaro.org>
Diffstat (limited to 'drivers/clocksource')
-rw-r--r--drivers/clocksource/arm_arch_timer.c10
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/clocksource/arm_arch_timer.c b/drivers/clocksource/arm_arch_timer.c
index fbd9ccd5e114..5d527895c74d 100644
--- a/drivers/clocksource/arm_arch_timer.c
+++ b/drivers/clocksource/arm_arch_timer.c
@@ -19,6 +19,7 @@
#include <linux/of_address.h>
#include <linux/io.h>
#include <linux/slab.h>
+#include <linux/sched_clock.h>
#include <asm/arch_timer.h>
#include <asm/virt.h>
@@ -471,6 +472,15 @@ static int __init arch_timer_register(void)
goto out;
}
+ clocksource_register_hz(&clocksource_counter, arch_timer_rate);
+ cyclecounter.mult = clocksource_counter.mult;
+ cyclecounter.shift = clocksource_counter.shift;
+ timecounter_init(&timecounter, &cyclecounter,
+ arch_counter_get_cntvct());
+
+ /* 56 bits minimum, so we assume worst case rollover */
+ sched_clock_register(arch_timer_read_counter, 56, arch_timer_rate);
+
if (arch_timer_use_virtual) {
ppi = arch_timer_ppi[VIRT_PPI];
err = request_percpu_irq(ppi, arch_timer_handler_virt,
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