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Date:   Mon, 28 Sep 2020 22:36:45 -0700
From:   Nicolin Chen <nicoleotsuka@gmail.com>
To:     Dmitry Osipenko <digetx@gmail.com>
Cc:     Thierry Reding <thierry.reding@gmail.com>,
        linux-kernel@vger.kernel.org, krzk@kernel.org,
        jonathanh@nvidia.com, iommu@lists.linux-foundation.org,
        linux-tegra@vger.kernel.org
Subject: Re: [PATCH 3/5] iommu/tegra-smmu: Use iommu_fwspec in
 .probe_/.attach_device()
Message-ID: <20200929053645.GA16611@Asurada-Nvidia>
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On Tue, Sep 29, 2020 at 07:06:37AM +0300, Dmitry Osipenko wrote:
> ...
> >> As I mentioned in another reply, I think tegra_smmu_find() should be all
> >> you need in this case.
> > 
> > This function is used by .probe_device() where its dev pointer is
> > an SMMU client. IIUC, tegra_smmu_find() needs np pointer of "mc".
> > For a PCI device that doesn't have a DT node with iommus property,
> > not sure how we can use tegra_smmu_find().
> 
> Perhaps you could get np from struct pci_dev.bus?

Possibly yes...but I was hoping the solution would be potentially
reused by other devices that don't have DT nodes, USB for example,
though I haven't tested with current version.