[PATCH 2/6] arm64: Allow mismatched 32-bit EL0 support

Catalin Marinas catalin.marinas at arm.com
Wed Oct 28 07:12:04 EDT 2020


On Tue, Oct 27, 2020 at 09:51:14PM +0000, Will Deacon wrote:
> +static bool has_32bit_el0(const struct arm64_cpu_capabilities *entry, int scope)
> +{
> +	return has_cpuid_feature(entry, scope) || __allow_mismatched_32bit_el0;
> +}
> +
>  static bool has_useable_gicv3_cpuif(const struct arm64_cpu_capabilities *entry, int scope)
>  {
>  	bool has_sre;
> @@ -1803,7 +1851,7 @@ static const struct arm64_cpu_capabilities arm64_features[] = {
>  		.desc = "32-bit EL0 Support",
>  		.capability = ARM64_HAS_32BIT_EL0,
>  		.type = ARM64_CPUCAP_SYSTEM_FEATURE,
> -		.matches = has_cpuid_feature,
> +		.matches = has_32bit_el0,

Ah, so this one reports 32-bit EL0 support even if no CPU actually
supports 32-bit (passing the command line option on TX2 would come up
with 32-bit EL0 in dmesg). I'd rather hide the .desc above and print the
information elsewhere when have at least one CPU supporting this.

-- 
Catalin



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