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=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no 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 D1C68C433E1 for ; Mon, 29 Mar 2021 15:40:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8E7106196E for ; Mon, 29 Mar 2021 15:40:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230366AbhC2Pjb convert rfc822-to-8bit (ORCPT ); Mon, 29 Mar 2021 11:39:31 -0400 Received: from aposti.net ([89.234.176.197]:58228 "EHLO aposti.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230167AbhC2PjQ (ORCPT ); Mon, 29 Mar 2021 11:39:16 -0400 Date: Mon, 29 Mar 2021 16:39:02 +0100 From: Paul Cercueil Subject: Re: [PATCH] drm: DON'T require each CRTC to have a unique primary plane To: Maxime Ripard Cc: Maarten Lankhorst , Thomas Zimmermann , David Airlie , Daniel Vetter , Simon Ser , od@zcrc.me, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org Message-Id: <25MQQQ.YYKN0GE2YPZN1@crapouillou.net> In-Reply-To: <20210329153541.a3yil2aqsrtf2nlj@gilmour> References: <20210327112214.10252-1-paul@crapouillou.net> <20210329140731.tvkfxic4fu47v3rz@gilmour> <20210329153541.a3yil2aqsrtf2nlj@gilmour> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8BIT Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Le lun. 29 mars 2021 à 17:35, Maxime Ripard a écrit : > On Mon, Mar 29, 2021 at 04:15:28PM +0100, Paul Cercueil wrote: >> Hi Maxime, >> >> Le lun. 29 mars 2021 à 16:07, Maxime Ripard a >> écrit : >> > On Sat, Mar 27, 2021 at 11:22:14AM +0000, Paul Cercueil wrote: >> > > The ingenic-drm driver has two mutually exclusive primary >> planes >> > > already; so the fact that a CRTC must have one and only one >> primary >> > > plane is an invalid assumption. >> > >> > I mean, no? It's been documented for a while that a CRTC should >> only >> > have a single primary, so I'd say that the invalid assumption was >> that >> > it was possible to have multiple primary planes for a CRTC. >> >> Documented where? >> >> I did read the doc of "enum drm_plane_type" in , >> and the >> DRM_PLANE_TYPE_PRIMARY describes my two planes, so I went with that. > > At least since 4.9, this was in the documentation generated for DRM: > https://elixir.bootlin.com/linux/v4.9.263/source/drivers/gpu/drm/drm_plane.c#L43 Ok, I read that as "all drivers should provide AT LEAST one primary plane per CRTC", and not as "all drivers should provide ONE AND ONLY ONE primary plane per CRTC". My bad. -Paul