[U-Boot] [PATCH 1/2] ARM: add wfi assembly macro

[Marek Vasut]

Dear Rob Herring,

> On 12/02/2012 10:58 PM, Marek Vasut wrote:
> > Dear Rob Herring,
> > 
> >> From: Rob Herring <rob.herring at calxeda.com>
> >> 
> >> Since wfi instruction is only available on ARMv7, add a conditional
> >> macro for it.
> >> 
> >> Signed-off-by: Rob Herring <rob.herring at calxeda.com>
> >> ---
> >> 
> >>  arch/arm/include/asm/system.h |    6 ++++++
> >>  1 file changed, 6 insertions(+)
> >> 
> >> diff --git a/arch/arm/include/asm/system.h
> >> b/arch/arm/include/asm/system.h index 2b28a26..2f6aecd 100644
> >> --- a/arch/arm/include/asm/system.h
> >> +++ b/arch/arm/include/asm/system.h
> >> @@ -61,6 +61,12 @@
> >> 
> >>  #define nop() __asm__ __volatile__("mov\tr0,r0\t@ nop\n\t");
> >> 
> >> +#ifdef __ARM_ARCH_7A__
> >> +#define wfi() __asm__ __volatile__ ("wfi" : : : "memory")
> >> +#else
> >> +#define wfi()
> >> +#endif
> > 
> > Won't this break other (non-arm) systems? Moreover, maybe you can make
> > this an (inline) function instead?
> 
> How? It is in an ARM specific header and empty on anything but ARMv7
> enabled compiler. This follows the kernel implementation and the nop above.

Ok, I missed the arch/arm. It's ok then, sorry for the noise.
[...]

Best regards,
Marek Vasut