Re: [PATCH v4 0/7] Clocksource changes for Pistachio CPUFreq.

[Ralf Baechle <ralf@linux-mips.org>]

Daniel,

On Mon, Jul 27, 2015 at 03:00:11PM +0100, Govindraj Raja wrote:

> From: Ezequiel Garcia <ezequiel.garcia@imgtec.com>
> 
> The purpose of this patchset is to support CPUFreq on Pistachio SoC.
> However, given Pistachio uses the MIPS GIC clocksource and clockevent drivers
> (clocked from the CPU), adding CPUFreq support needs some work.
> 
> This patchset changes the MIPS GIC clockevent driver to update the frequency of
> the per-cpu clockevents using a clock notifier.
> 
> Then, we add a clocksource driver for IMG Pistachio SoC, based on the 
> general purpose timers. The SoC only provides four timers, so we can't
> use them to implement the four clockevents and the clocksource.
> 
> However, we can use one of these timers to provide a clocksource and a
> sched clock. Given the general purpose timers are clocked from the peripheral
> system clock tree, they are not affected by CPU rate changes.
> 
> Patches 1 to 3 are just style cleaning and preparation work.
> Patch 4 adds the clockevent frequency update.
> Patches 5 and 6 add the new clocksource driver.
> Patch 7 introduces an option to enable the timer based clocksource on Pistachio.

if you're happy with this series feel free to add my ack to patch 7/7
which is the only one that touches arch/mips.

Alternatively I can carry this in the MIPS tree which would have tbe
benefit of better testing.

  Ralf