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Date:   Thu, 12 Oct 2023 13:56:09 +0100
From:   Will Deacon <will@kernel.org>
To:     Robin Murphy <robin.murphy@arm.com>
Cc:     joro@8bytes.org, iommu@lists.linux.dev, jgg@nvidia.com,
        baolu.lu@linux.intel.com, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v5 5/7] iommu/arm-smmu: Don't register fwnode for legacy
 binding
Message-ID: <20231012125609.GA12142@willie-the-truck>
References: <cover.1697047261.git.robin.murphy@arm.com>
 <3a5cd62dd21ed58f337bb9a389d301054e503dc3.1697047261.git.robin.murphy@arm.com>
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On Wed, Oct 11, 2023 at 07:14:52PM +0100, Robin Murphy wrote:
> When using the legacy binding we bypass the of_xlate mechanism, so avoid
> registering the instance fwnodes which act as keys for that. This will
> help __iommu_probe_device() to retrieve the registered ops the same way
> as for x86 etc. when no fwspec has previously been set up by of_xlate.
> 
> Reviewed-by: Jason Gunthorpe <jgg@nvidia.com>
> Signed-off-by: Robin Murphy <robin.murphy@arm.com>
> ---
>  drivers/iommu/arm/arm-smmu/arm-smmu.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/arm/arm-smmu/arm-smmu.c b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> index d6d1a2a55cc0..4b83a3adacd6 100644
> --- a/drivers/iommu/arm/arm-smmu/arm-smmu.c
> +++ b/drivers/iommu/arm/arm-smmu/arm-smmu.c
> @@ -2161,7 +2161,8 @@ static int arm_smmu_device_probe(struct platform_device *pdev)
>  		return err;
>  	}
>  
> -	err = iommu_device_register(&smmu->iommu, &arm_smmu_ops, dev);
> +	err = iommu_device_register(&smmu->iommu, &arm_smmu_ops,
> +				    using_legacy_binding ? NULL : dev);
>  	if (err) {
>  		dev_err(dev, "Failed to register iommu\n");
>  		iommu_device_sysfs_remove(&smmu->iommu);
> -- 
> 2.39.2.101.g768bb238c484.dirty

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

Will