schedule_timeout sleeps too long after dividing CPU frequency
slash.tmp at free.fr
Wed May 20 09:21:45 PDT 2015
Thanks for your detailed answer.
On 18/05/2015 13:54, Russell King - ARM Linux wrote:
> For a SoC where WFI is not programmed to cause anything other than
> the architecture specified dormant behaviour, WFI will not cause the
> TWD to stop.
According to the hardware engineers, my SoC does not support any
But I didn't see the "clean" way to make the kernel aware of this.
Is this an acceptable patch? (I have my doubts.)
diff --git a/arch/arm/kernel/smp_twd.c b/arch/arm/kernel/smp_twd.c
index 6591e26..300f13a 100644
@@ -295,6 +295,10 @@ static void twd_timer_setup(void)
clk->name = "local_timer";
clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
+ /*** Tango does not implement low power modes ***/
+ clk->features &= ~CLOCK_EVT_FEAT_C3STOP;
clk->rating = 350;
clk->set_mode = twd_set_mode;
clk->set_next_event = twd_set_next_event;
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