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 717F0EB64DA for ; Wed, 5 Jul 2023 10:00:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229901AbjGEKAS (ORCPT ); Wed, 5 Jul 2023 06:00:18 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36348 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231482AbjGEKAR (ORCPT ); Wed, 5 Jul 2023 06:00:17 -0400 Received: from mout-p-101.mailbox.org (mout-p-101.mailbox.org [80.241.56.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 98462E41 for ; Wed, 5 Jul 2023 03:00:15 -0700 (PDT) Received: from smtp1.mailbox.org (smtp1.mailbox.org [IPv6:2001:67c:2050:b231:465::1]) (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-101.mailbox.org (Postfix) with ESMTPS id 4QwwBf62Pcz9st7; Wed, 5 Jul 2023 12:00:10 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mailbox.org; s=mail20150812; t=1688551210; 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=RQq2nzlBvqs3LR1ATp7LlQkGuwAdsoU/HQzWWBGdLIw=; b=bXVa/v8QQNAnFngBbvUcsMVuH+/SPoQAZfblpknVcvwO6MGo/8NvOLZUIKyxmIU6hd31dL h10otONCenoNL9X/8ZhxH5tbqT2jTxS7DuRQ3tfqJiiHcPuF6x1AsUqfr8p1kxqgJ+Csbk OCl56xkrYxHXbdV6KFuYrE8IP14+W8TTwMNAF85xYtDBW1R5Eg2bHp9F1LEi08wO3tMBVU 5iatrMHZvgyRNfQrbnbQZsNzkbt0Fa7eNE3/C5IBGJyA2slAQVttxnF31KiF15Yb+U4Nh9 nyFHA1xUmekdto9eR1l/5JaAOkdVsD0SRyNXbgKZOmNRkj0x/2N8bPKNpJtLAw== Message-ID: Date: Wed, 5 Jul 2023 12:00:07 +0200 MIME-Version: 1.0 Subject: Re: [PATCH v4 1/6] drm: allow DRM_MODE_PAGE_FLIP_ASYNC for atomic commits Content-Language: de-CH-frami, en-CA To: Sebastian Wick , =?UTF-8?Q?Andr=c3=a9_Almeida?= Cc: pierre-eric.pelloux-prayer@amd.com, =?UTF-8?B?TWFyZWsgT2zFocOhaw==?= , Italo Nicola , Randy Dunlap , linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, wayland-devel@lists.freedesktop.org, Pekka Paalanen , dri-devel@lists.freedesktop.org, kernel-dev@igalia.com, alexander.deucher@amd.com, hwentlan@amd.com, christian.koenig@amd.com, joshua@froggi.es References: <20230701020917.143394-1-andrealmeid@igalia.com> <20230701020917.143394-2-andrealmeid@igalia.com> From: =?UTF-8?Q?Michel_D=c3=a4nzer?= In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-MBO-RS-ID: 42841dc9c0b77bbe99d X-MBO-RS-META: x149rw5ddd5djf7m5nw57pee9poq3fos Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 7/4/23 19:06, Sebastian Wick wrote: > On Sat, Jul 1, 2023 at 4:09 AM André Almeida wrote: >> >> @@ -949,6 +949,15 @@ struct hdr_output_metadata { >> * Request that the page-flip is performed as soon as possible, ie. with no >> * delay due to waiting for vblank. This may cause tearing to be visible on >> * the screen. >> + * >> + * When used with atomic uAPI, the driver will return an error if the hardware >> + * doesn't support performing an asynchronous page-flip for this update. >> + * User-space should handle this, e.g. by falling back to a regular page-flip. >> + * >> + * Note, some hardware might need to perform one last synchronous page-flip >> + * before being able to switch to asynchronous page-flips. As an exception, >> + * the driver will return success even though that first page-flip is not >> + * asynchronous. > > What would happen if one commits another async KMS update before the > first page flip? Does one receive EAGAIN, does it amend the previous > commit? Should be the former. DRM_MODE_PAGE_FLIP_ASYNC just means the flip may complete outside of vertical blank, it doesn't change anything else. -- Earthling Michel Dänzer | https://redhat.com Libre software enthusiast | Mesa and Xwayland developer