Date: Thu, 17 Aug 2017 15:45:39 +0200
From: Joerg Roedel <jroedel@suse.de>
To: Lucas Stach <l.stach@pengutronix.de>
Cc: Joerg Roedel <joro@8bytes.org>, iommu@lists.linux-foundation.org,
        linux-kernel@vger.kernel.org,
        Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>,
        Russell King <linux+etnaviv@armlinux.org.uk>,
        Christian Gmeiner <christian.gmeiner@gmail.com>,
        David Airlie <airlied@linux.ie>, etnaviv@lists.freedesktop.org,
        dri-devel@lists.freedesktop.org
Subject: Re: [PATCH 06/13] drm/etnaviv: Use sychronized interface of the
 IOMMU-API
Message-ID: <20170817134539.GJ2853@suse.de>
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 <1502976758.19806.25.camel@pengutronix.de>
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Hi Lucas,

On Thu, Aug 17, 2017 at 03:32:38PM +0200, Lucas Stach wrote:
> I don't think this is necessary. Etnaviv has managed and batched up TLB
> flushes from day 1, as they don't happen through the MMU MMIO interface,
> but through the GPU command stream.
> 
> So if my understanding of this series is correct, Etnaviv is just fine
> with the changed semantics of the unsynchronized map/unmap calls.

This is not about any TLB on the GPU that could be flushed through the
GPU command stream, but about the TLB in the IOMMU device. Or is this
actually the same on this hardware? Which IOMMU-driver is use there?


Regards,

	Joerg