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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 6029EC2FC18 for ; Thu, 17 Aug 2023 10:38:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1349978AbjHQKiO (ORCPT ); Thu, 17 Aug 2023 06:38:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38158 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1349903AbjHQKh7 (ORCPT ); Thu, 17 Aug 2023 06:37:59 -0400 Received: from mout-p-102.mailbox.org (mout-p-102.mailbox.org [80.241.56.152]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 60DB02D54 for ; Thu, 17 Aug 2023 03:37:57 -0700 (PDT) Received: from smtp2.mailbox.org (smtp2.mailbox.org [10.196.197.2]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-384) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by mout-p-102.mailbox.org (Postfix) with ESMTPS id 4RRM0J5vynz9sTy; Thu, 17 Aug 2023 12:37:52 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mailbox.org; s=mail20150812; t=1692268672; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lWR+OTy0bw/7gHQyaHmIFXg9eXwe63Tk14rDVr8H2HA=; b=O/p3hcyzbaQGOKsoyt2Eg4Za8zUYXNQnGbaphodEBOKp7SxF7dfYGeQ4cfKHwI0ZTACYn6 iLoR3jmcefj0Ggm/WY6dHUJHxPK9V+WpZFCnJeCf2+l+LgEmBUrDg+H1FfudChN+UhMdgM J6fNmMruz2N/hu5/6rweqQJDsUP5Elzl2sZLFP9EmwD2oosL0p9KfIXjScjgnUFGkwd9Hu 0g3Xo0SMUW5OBIN9pp48UOYOl+irz6E9K4knC5AgFhs+7Qt9Jkt9cyS1C6MwVYI/CG6I7y DU/1ONnkFZrRDrEtRPfK8u1gXAqhhbvUp4D2LiJ2ijo7Bp8uyySiRqU2RzY6+w== Message-ID: <1b23576d-1649-ff5c-6273-b54729ea46d8@mailbox.org> Date: Thu, 17 Aug 2023 12:37:49 +0200 MIME-Version: 1.0 Subject: Re: [PATCH v6 6/6] drm/doc: Define KMS atomic state set Content-Language: de-CH-frami, en-CA To: =?UTF-8?Q?Andr=c3=a9_Almeida?= , dri-devel@lists.freedesktop.org, amd-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org, wayland-devel@lists.freedesktop.org Cc: pierre-eric.pelloux-prayer@amd.com, Pekka Paalanen , Daniel Vetter , =?UTF-8?B?J01hcmVrIE9sxaHDoWsn?= , Randy Dunlap , Pekka Paalanen , Daniel Stone , hwentlan@amd.com, Rob Clark , ville.syrjala@linux.intel.com, kernel-dev@igalia.com, alexander.deucher@amd.com, Dave Airlie , christian.koenig@amd.com, joshua@froggi.es References: <20230815185710.159779-1-andrealmeid@igalia.com> <20230815185710.159779-7-andrealmeid@igalia.com> From: =?UTF-8?Q?Michel_D=c3=a4nzer?= In-Reply-To: <20230815185710.159779-7-andrealmeid@igalia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-MBO-RS-ID: f9a431e141f714a5fd0 X-MBO-RS-META: pbseorajysen1cko9xh3sm3of47nd13r Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/15/23 20:57, André Almeida wrote: > From: Pekka Paalanen > > Specify how the atomic state is maintained between userspace and > kernel, plus the special case for async flips. > > Signed-off-by: Pekka Paalanen > Signed-off-by: André Almeida [...] > +An atomic commit with the flag DRM_MODE_PAGE_FLIP_ASYNC is allowed to > +effectively change only the FB_ID property on any planes. No-operation changes > +are ignored as always. [...] During the hackfest in Brno, it was mentioned that a commit which re-sets the same FB_ID could actually have an effect with VRR: It could trigger scanout of the next frame before vertical blank has reached its maximum duration. Some kind of mechanism is required for this in order to allow user space to perform low frame rate compensation. -- Earthling Michel Dänzer | https://redhat.com Libre software enthusiast | Mesa and Xwayland developer