From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-0.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED,URIBL_RHS_DOB autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4827AC10F0E for ; Thu, 18 Apr 2019 09:14:06 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 219552183F for ; Thu, 18 Apr 2019 09:14:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388404AbfDRJOF (ORCPT ); Thu, 18 Apr 2019 05:14:05 -0400 Received: from relay9-d.mail.gandi.net ([217.70.183.199]:43915 "EHLO relay9-d.mail.gandi.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388346AbfDRJOE (ORCPT ); Thu, 18 Apr 2019 05:14:04 -0400 X-Originating-IP: 90.88.160.238 Received: from aptenodytes (aaubervilliers-681-1-42-238.w90-88.abo.wanadoo.fr [90.88.160.238]) (Authenticated sender: paul.kocialkowski@bootlin.com) by relay9-d.mail.gandi.net (Postfix) with ESMTPSA id 2ADDEFF813; Thu, 18 Apr 2019 09:13:58 +0000 (UTC) Message-ID: <03187f79f37fdb45f3a774e200e21a29167776a8.camel@bootlin.com> Subject: Re: Support for 2D engines/blitters in V4L2 and DRM From: Paul Kocialkowski To: Tomasz Figa Cc: Daniel Vetter , Nicolas Dufresne , Linux Kernel Mailing List , Alexandre Courbot , Maxime Ripard , Hans Verkuil , Mauro Carvalho Chehab , Linux Media Mailing List , dri-devel , Thomas Petazzoni , Eric Anholt , Rob Clark , Dave Airlie , Maarten Lankhorst Date: Thu, 18 Apr 2019 11:13:57 +0200 In-Reply-To: References: <0df3d4b5178d8a37b67b275e0771741c6c268de3.camel@bootlin.com> <20190418081816.GO13337@phenom.ffwll.local> <522d6a7734a29df47fe11f5f6311b49e14dabae0.camel@bootlin.com> Organization: Bootlin Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.32.1 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Thu, 2019-04-18 at 18:09 +0900, Tomasz Figa wrote: > On Thu, Apr 18, 2019 at 5:55 PM Paul Kocialkowski > wrote: > > Hi Daniel, > > > > On Thu, 2019-04-18 at 10:18 +0200, Daniel Vetter wrote: > > > On Wed, Apr 17, 2019 at 08:10:15PM +0200, Paul Kocialkowski wrote: > > > > Hi Nicolas, > > > > > > > > I'm detaching this thread from our V4L2 stateless decoding spec since > > > > it has drifted off and would certainly be interesting to DRM folks as > > > > well! > > > > > > > > For context: I was initially talking about writing up support for the > > > > Allwinner 2D engine as a DRM render driver, where I'd like to be able > > > > to batch jobs that affect the same destination buffer to only signal > > > > the out fence once when the batch is done. We have a similar issue in > > > > v4l2 where we'd like the destination buffer for a set of requests (each > > > > covering one H264 slice) to be marked as done once the set was decoded. > > > > > > Out of curiosity, what area did you find a 2D blitter useful for? The initial motivation is to bring up a DDX with that for platforms that have 2D engines but no free software GPU drivers yet. I also have a personal project in the works where I'd like to implement accelerated UI rendering in 2D. The idea is to avoid using GL entirely. That last point is in part because I have a GPU-less device that I want to get going with mainline: http://linux-sunxi.org/F60_Action_Camera Cheers, Paul -- Paul Kocialkowski, Bootlin Embedded Linux and kernel engineering https://bootlin.com