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Date:   Fri, 21 Aug 2020 09:07:25 +0100
From:   Will Deacon <will@kernel.org>
To:     Robin Murphy <robin.murphy@arm.com>
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Subject: Re: [PATCH 07/18] iommu/arm-smmu: Remove arch/arm workaround
Message-ID: <20200821080724.GA20060@willie-the-truck>
References: <cover.1597931875.git.robin.murphy@arm.com>
 <ef39be82b98d2471c9e99c82d0eeda37ba30e4fa.1597931876.git.robin.murphy@arm.com>
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On Thu, Aug 20, 2020 at 04:08:26PM +0100, Robin Murphy wrote:
> Now that arch/arm is wired up for default domains and iommu-dma, remove
> the add_device workaround.
> 
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>  drivers/iommu/arm/arm-smmu/arm-smmu.c | 10 ----------
>  1 file changed, 10 deletions(-)
> 
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> index 09c42af9f31e..4e52d8cb67dd 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> @@ -1164,17 +1164,7 @@ static int arm_smmu_attach_dev(struct iommu_domain *domain, struct device *dev)
>  		return -ENXIO;
>  	}
>  
> -	/*
> -	 * FIXME: The arch/arm DMA API code tries to attach devices to its own
> -	 * domains between of_xlate() and probe_device() - we have no way to cope
> -	 * with that, so until ARM gets converted to rely on groups and default
> -	 * domains, just say no (but more politely than by dereferencing NULL).
> -	 * This should be at least a WARN_ON once that's sorted.
> -	 */
>  	cfg = dev_iommu_priv_get(dev);
> -	if (!cfg)
> -		return -ENODEV;
> -
>  	smmu = cfg->smmu;
>  
>  	ret = arm_smmu_rpm_get(smmu);

Acked-by: Will Deacon <will@kernel.org>

Will