On Tue, Jan 24, 2017 at 03:16:39PM +0300, Alexander Kochetkov wrote:

clocksource and shed_clock provided by arm-global-timer is quite
unstable, because their rate depends on cpu frequency.
So disable arm-global-timer and use clocksource and sched_clock
from rockchip_timer.
It is impossible get stable clocksource having rockchip_timer and
arm-global-timer enabled at the same time. Because arm-global-timer
looks like a better candidate for the kernel: it has higher
frequency and rating.

Disabling arm-global-timer doesn't leave kernel without
clockevents as there is another clockevent provider (smp-twd).

Hi Alexander,

sorry, I will rewrite the description because of the grammatical errors. I
don't want to give you the feeling I'm lecturing you, my English is not perfect
but it will be simpler to give the full descr with the typos fixed.

"
The clocksource and the sched_clock provided by the arm_global_timer are quite
unstable because their rates depend on the cpu frequency.

On the other side, the arm_global_timer has a higher rating than the
rockchip_timer, it will be selected by default by the time framework while
we want to use the stable rockchip clocksource.

Let's disable the arm_global_timer in order to have the rockchip clocksource
selected by default.
"

This patch should go at the end of the patchset when the clocksource is
implemented in the rockchip_timer.

-- 

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