[PATCH] ARM: automatically select OMAP3_PMU if we try to use perf on OMAP3

Will Deacon will.deacon at arm.com
Thu Jun 30 17:51:09 EDT 2011


On Thu, Jun 30, 2011 at 02:27:02PM +0100, Arnd Bergmann wrote:
> On Thursday 30 June 2011, Bryan Wu wrote:
> > On Tue, Jun 28, 2011 at 9:57 PM, Will Deacon <will.deacon at arm.com> wrote:
> 
> > >
> > > This issue has been discussed on the list in the past and I still think that
> > > it would be better for your config to select OMAP3_EMU explicitly. If we do
> > > that here unconditionally then we end up also bringing in OC_ETM which isn't
> > > something that sounds like a good idea (may have implications for power
> > > consumption in production hardware?).
> > >
> > I quite understand your concern. How about this one?
> > ----
> > diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
> > index 2fd0911..e53f9e4 100644
> > --- a/arch/arm/Kconfig
> > +++ b/arch/arm/Kconfig
> > @@ -1084,10 +1084,10 @@ config XSCALE_PMU
> >         default y
> > 
> >  config CPU_HAS_PMU
> > -       depends on (CPU_V6 || CPU_V6K || CPU_V7 || XSCALE_PMU) && \
> > -                  (!ARCH_OMAP3 || OMAP3_EMU)
> > +       depends on CPU_V6 || CPU_V6K || CPU_V7 || XSCALE_PMU
> >         default y
> >         bool
> > +       select OMAP3_EMU if (PERF_EVENTS && ARCH_OMAP3)
> > 
> >  config MULTI_IRQ_HANDLER
> >         bool
> > 
> 
> As far as I can tell, it still has the same issue. I think the existing
> code is better. If you want to support HW_PERF_EVENTS on OMAP3, just
> turn on OMAP3_EMU. Where's the problem with that?

Yup. Although the new patch does address my previous technical concerns, I'm
still not happy with it. Just select OMAP3_EMU!

> [1] http://en.wikipedia.org/wiki/COMEFROM

Ha, that really is horrible!

Will



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