From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dave Airlie Subject: Re: [RFC v2 8/8] drm: tegra: Add gr2d device Date: Tue, 27 Nov 2012 17:33:59 +1000 Message-ID: References: <1353935954-13763-1-git-send-email-tbergstrom@nvidia.com> <1353935954-13763-9-git-send-email-tbergstrom@nvidia.com> <50B46336.8030605@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Return-path: In-Reply-To: <50B46336.8030605-DDmLM1+adcrQT0dZR+AlfA@public.gmane.org> Sender: linux-tegra-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: =?ISO-8859-1?Q?Terje_Bergstr=F6m?= Cc: "thierry.reding-RM9K5IK7kjKj5M59NBduVrNAH6kLmebB@public.gmane.org" , "linux-tegra-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "dri-devel-PD4FTy7X32lNgt0PjOBp9y5qC8QIuHrW@public.gmane.org" , "linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , Arto Merilainen List-Id: dri-devel@lists.freedesktop.org > > Third would be having a firewall in 2D driver checking the stream and > ensuring all registers that accept addresses are written by values > derived from dmabufs. I haven't tried implementing this, but it'd > involve a lookup table in kernel and CPU reading through the command > stream. Offsets and sizes would also need to be validated. There would > be a performance hit. This is the standard mechanism, and what exynos does as well. The per process VM method is also used as an extension to this on some hw. Dave.