Re: [PATCH v3 0/5] clocksource: sun5i: Support parent clock rate changes

From: Daniel Lezcano
Date: Fri Mar 20 2015 - 10:04:37 EST


On 03/19/2015 11:53 PM, Maxime Ripard wrote:
Hi Daniel,

On Thu, Mar 05, 2015 at 11:20:51AM +0100, Maxime Ripard wrote:
Hi,

The Allwinner HS timers have the AHB clock as their parent
clock. Since this clock is shared with other devices, we could very
well have another driver requesting a rate change of that clock,
making our timer change frequency at the same time.

This is especially true on the A31, where the DMA controller needs to
do such a rate change, making the HS timer unreliable at the time on
the A31.

This serie makes some cleanups and implements clock notifiers to be
able to reflect such rate changes and make sure that the timer is
always working.

Maxime

Changes from v2:
- Rebased on top of v4.0-rc1
- Removed the local_irq_save/restore around clockevents_update_freq

Changes from v1:
- Changed the interrupt name to its previous value

Maxime Ripard (5):
clocksource: sun5i: Switch to request_irq
clocksource: sun5i: Use of_io_request_and_map
clocksource: sun5i: Remove sched_clock
clocksource: sun5i: Refactor the current code
clocksource: sun5i: Add clock notifiers

Have these patches been merged?

If not, it woulde be great if the third one ("clocksource: sun5i:
Remove sched_clock") was merged for 4.0.

The sched_clock we use on some system is this timer's, and since we
started using cpufreq, the cpu clock (that is one of the timer's clock
indirect parent) now changes, along with the actual sched_clock rate.

We can safely remove the sched_clock on those systems, since we have
other reliable sched_clock in the system.

Ok, I applied the patch for v4.0-rc5 but I had to fix a conflict and change the changelog.

Mind to test it works ?

git.linaro.org/people/daniel.lezcano/linux.git clockevents/v4.0-rc4

Thanks
-- Daniel

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