[RFCv2 PATCH 26/36] iommu/arm-smmu-v3: Add support for Hardware Translation Table Update

[Yisheng Xie]

Hi Jean,

On 2017/10/6 21:31, Jean-Philippe Brucker wrote:
> If the SMMU supports it and the kernel was built with HTTU support, enable
> +	if (IS_ENABLED(CONFIG_ARM64_HW_AFDBM) && (reg & (IDR0_HA | IDR0_HD))) {
> +		smmu->features |= ARM_SMMU_FEAT_HA;
> +		if (reg & IDR0_HD)
> +			smmu->features |= ARM_SMMU_FEAT_HD;
> +	}

What is relationship of armv8.1 HW_AFDBM and SMMUv3 HTTU? I mean why we need
IS_ENABLED(CONFIG_ARM64_HW_AFDBM) ?

If CONFIG_ARM64_HW_AFDBM=y but the process do not support ARMv8.1, should it also
enable related feature for SMMUv3?

Thanks
Yisheng Xie
> +
>  	/*
>  	 * If the CPU is using VHE, but the SMMU doesn't support it, the SMMU
>  	 * will create TLB entries for NH-EL1 world and will miss the
>