Fix preempt-rt on AT91

[Alexandre Belloni]

On 18/01/2016 at 21:30:13 +0100, Sebastian Andrzej Siewior wrote :
> Well, if it works properly and does not lead to any new bugs or
> anything else then nobody will mind I guess.
> 

Yeah, the DT guys were not happy about the patch set, I'll try to work
around using DT ;)

> >> All in all, care to forwarded the working pieces from -RT patch set
> >> upstream? I problem I have here is mostly that I can't the patches on
> >> actual hardware. Disabling the PIT and running on the other clocksource
> >> isn't that -RT specific after all :)
> > 
> > I'd say that the only remaining part is the IRQ freeing/requesting but
> > as I said, this can't land in mainline as is. I still plan to work on
> > that later.
> > I'd say that most people running linux on at91 are already using the tcb
> > as the clocksource, this is already available in the mainline and is the
> > default unless the TCBs are used for something else.
> 
> Wasn't there one of the patches to increase the frequency of the TCB
> clocksource from the default to something higher?
> 

Indeed, it may be worth mainlining that one.

-- 
Alexandre Belloni, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com