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Date:   Tue, 28 May 2019 23:16:26 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Lu Baolu <baolu.lu@linux.intel.com>
Cc:     David Woodhouse <dwmw2@infradead.org>,
        Joerg Roedel <joro@8bytes.org>, kevin.tian@intel.com,
        ashok.raj@intel.com, dima@arista.com, tmurphy@arista.com,
        linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org,
        jacob.jun.pan@intel.com
Subject: Re: [PATCH v4 10/15] iommu/vt-d: Probe DMA-capable ACPI name space
 devices
Message-ID: <20190529061626.GA26055@infradead.org>
References: <20190525054136.27810-1-baolu.lu@linux.intel.com>
 <20190525054136.27810-11-baolu.lu@linux.intel.com>
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On Sat, May 25, 2019 at 01:41:31PM +0800, Lu Baolu wrote:
> Some platforms may support ACPI name-space enumerated devices
> that are capable of generating DMA requests. Platforms which
> support DMA remapping explicitly declares any such DMA-capable
> ACPI name-space devices in the platform through ACPI Name-space
> Device Declaration (ANDD) structure and enumerate them through
> the Device Scope of the appropriate remapping hardware unit.
> 
> Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>

Isn't this something that should be handled through the IOMMU API so
that it covers other IOMMU types as well?

How does this scheme compare to the one implemented in
drivers/acpi/arm64/iort.c?