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SubjectRe: [PATCH v2 2/2] ARM: at91: pm: switch to the PIE infrastructure
On 29/06/2016 at 08:12:21 +0200, Alexander Stein wrote :
> > +#if defined(CONFIG_CPU_V7)
> > + dsb();
> > + wfi();
> > +#else
> > + asm volatile ("mcr p15, 0, %0, c7, c0, 4" \
> > + : : "r" (0) : "memory");
> > +#endif
>
> Why not defining wfi() for __LINUX_ARM_ARCH__ < 7 as it is done for dsb() and
> friends in arch/arm/include/asm/barrier.h? So you can get rid of that #if
> completly.

Well, Russell said it was not useful because "there's no architected WFI
instruction which doesn't have CPU specific issues (hence why we have
cpu_do_idle() to abstract that)"

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

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