[GIT PULL] Renesas ARM Based SoC Init Delay Updates For v3.18

Simon Horman horms at verge.net.au
Mon Sep 8 19:02:18 PDT 2014

On Fri, Sep 05, 2014 at 05:27:18PM +0200, Arnd Bergmann wrote:
> On Monday 25 August 2014, Simon Horman wrote:
> > Hi Olof, Hi Kevin, Hi Arnd,
> > 
> > Please consider these Renesas ARM based SoC init delay updates for v3.18.
> > 
> While looking at your branches, I noticed that you go to great lengths
> to compute the correct lpj value and avoid the calibration.
> However, I believe the "modern" way to do this is to call
> register_current_timer_delay() in order to base the delay loop
> on the hardware timer instead of looping in the CPU. This is
> more accurate and more robust against CPU frequency scaling.

I may be wrong but my understanding is that Renesas SoCs may be
booted without a timer.

> I'm applying the patches now, but it's something you may want
> to look at in the future. On a related topic, your clocksource
> drivers could be simplified for the DT-only case by using
> CLOCKSOURCE_OF_DECLARE() instead of early_platform_init(), but
> I don't know what the impact would be for the arch/sh and legacy
> mach-shmobile cases.

Thanks, I will have that looked into.

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