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Re: [PATCH 2/5] irqchip/gic-v3: Make gic_enable_sre an inline function

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On Fri, Oct 02, 2015 at 05:37:51PM +0100, Marc Zyngier wrote:
> +static inline bool gic_enable_sre(void)
> +{
> +	u64 val;
> +
> +	asm volatile("mrs_s %0, " __stringify(ICC_SRE_EL1) : "=r" (val));
> +	if (val & ICC_SRE_EL1_SRE)
> +		return true;
> +
> +	val |= ICC_SRE_EL1_SRE;
> +	asm volatile("msr_s " __stringify(ICC_SRE_EL1) ", %0" : : "r" (val));
> +	isb();
> +	asm volatile("mrs_s %0, " __stringify(ICC_SRE_EL1) : "=r" (val));
> +
> +	return !!(val & ICC_SRE_EL1_SRE);
> +}

I don't think !! is needed ;). Apparently, from ISO C99: "When any
scalar value is converted to _Bool, the result is 0 if the value
compares equal to 0; otherwise, the result is 1."

-- 
Catalin
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Re: [PATCH 2/5] irqchip/gic-v3: Make gic_enable_sre an inline  function Catalin Marinas <catalin.marinas@arm.com> - 2015-10-08 18:00 +0200
  Re: [PATCH 2/5] irqchip/gic-v3: Make gic_enable_sre an inline function Marc Zyngier <marc.zyngier@arm.com> - 2015-10-08 18:10 +0200

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