From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lucas Stach Subject: Re: [PATCH 06/13] drm/etnaviv: Use sychronized interface of the IOMMU-API Date: Thu, 17 Aug 2017 16:03:54 +0200 Message-ID: <1502978634.19806.27.camel@pengutronix.de> References: <1502974596-23835-1-git-send-email-joro@8bytes.org> <1502974596-23835-7-git-send-email-joro@8bytes.org> <1502976758.19806.25.camel@pengutronix.de> <20170817134539.GJ2853@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20170817134539.GJ2853@suse.de> Sender: linux-kernel-owner@vger.kernel.org To: Joerg Roedel Cc: Joerg Roedel , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Suravee Suthikulpanit , Russell King , Christian Gmeiner , David Airlie , etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org List-Id: dri-devel@lists.freedesktop.org Am Donnerstag, den 17.08.2017, 15:45 +0200 schrieb Joerg Roedel: > 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? There is no IOMMU driver in use. Etnaviv just uses part of the IOMMU API to manage the GPU internal MMU, see drivers/gpu/drm/etnaviv/etnaviv_iommu.c Regards, Lucas