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Date:   Wed, 24 Jul 2019 19:55:51 +0200
From:   Christoph Hellwig <hch@lst.de>
To:     Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Cc:     Christoph Hellwig <hch@lst.de>,
        Russell King - ARM Linux admin <linux@armlinux.org.uk>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org,
        linux-arm-kernel@lists.infradead.org, Roger Quadros <rogerq@ti.com>
Subject: Re: [PATCH 2/2] arm: use swiotlb for bounce buffer on LPAE configs
Message-ID: <20190724175551.GA13073@lst.de>
References: <20190709142011.24984-1-hch@lst.de> <20190709142011.24984-3-hch@lst.de> <a447eae1bb46fe753f7a62fb8932e680b79b1635.camel@suse.de>
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On Wed, Jul 24, 2019 at 07:23:50PM +0200, Nicolas Saenz Julienne wrote:
> Out of curiosity, what is the reason stopping us from using dma-direct/swiotlb
> instead of arm_dma_ops altogether?

Nothing fundamental.  We just need to do a very careful piecemeal
migration as the arm code handles a ot of interesting corner case and
we need to ensure we don't break that.  I have various WIP patches
for the easier bits and we can work from there.