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=-6.0 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,T_DKIMWL_WL_HIGH,USER_AGENT_GIT 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 50892C28EBD for ; Sun, 9 Jun 2019 16:46:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 269F920833 for ; Sun, 9 Jun 2019 16:46:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560098782; bh=xZk6V8W47holid3x8sEAl6DZJWT45f42r7gly3AseKY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=q/OvXpgs5n8p6okNOsRNmu0OKzVi4g/a7aFE2Luz2BEdN/Ojt094ZlC/KtAYCtO9s zC7eJW3j4lsaEeSeO08tNGouybo+SGPMik8w8h2lA3vpn+azU55eJB6b3B36b+yyMC jDPOul3Q58cvQJt5XrQ6rqpyUQaIi1qfxgO7quD0= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729410AbfFIQqV (ORCPT ); Sun, 9 Jun 2019 12:46:21 -0400 Received: from mail.kernel.org ([198.145.29.99]:44352 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730337AbfFIQqO (ORCPT ); Sun, 9 Jun 2019 12:46:14 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 730C32081C; Sun, 9 Jun 2019 16:46:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1560098774; bh=xZk6V8W47holid3x8sEAl6DZJWT45f42r7gly3AseKY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GQ18AyBjCnfSORN4gXbYQ8iRohdH0bv+pvNM7o/1asCIyMPNCW0xCFLZDtLkWgfpl Q9xUVTJeG3EVrDW1JKBvttIqS4/EG0xqdFDExH9hrYDc1vX4hYFEuhLiIGv8ieMEFI OJgpqdaahKBsFbgCxZ/bmFU8jrjSxMwUtxkJbgpE= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Daniel Vetter , Nicholas Kazlauskas , Mario Kleiner , Alex Deucher Subject: [PATCH 5.1 56/70] drm: Fix timestamp docs for variable refresh properties. Date: Sun, 9 Jun 2019 18:42:07 +0200 Message-Id: <20190609164132.173948370@linuxfoundation.org> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190609164127.541128197@linuxfoundation.org> References: <20190609164127.541128197@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mario Kleiner commit 0cbd0adc4429930567083d18cc8c0fbc5f635d96 upstream. As discussed with Nicholas and Daniel Vetter (patchwork link to discussion below), the VRR timestamping behaviour produced utterly useless and bogus vblank/pageflip timestamps. We have found a way to fix this and provide sane behaviour. As of Linux 5.2, the amdgpu driver will be able to provide exactly the same vblank / pageflip timestamp semantic in variable refresh rate mode as in standard fixed refresh rate mode. This is achieved by deferring core vblank handling (drm_crtc_handle_vblank()) until the end of front porch, and also defer the sending of pageflip completion events until end of front porch, when we can safely compute correct pageflip/vblank timestamps. The same approach will be possible for other VRR capable kms drivers, so we can actually have sane and useful timestamps in VRR mode. This patch removes the section of the docs that describes the broken timestamp behaviour present in Linux 5.0/5.1. Fixes: ab7a664f7a2d ("drm: Document variable refresh properties") Link: https://patchwork.freedesktop.org/patch/285333/ Acked-by: Daniel Vetter Reviewed-by: Nicholas Kazlauskas Signed-off-by: Mario Kleiner Signed-off-by: Alex Deucher Link: https://patchwork.freedesktop.org/patch/msgid/20190418060157.18968-1-mario.kleiner.de@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/drm_connector.c | 6 ------ 1 file changed, 6 deletions(-) --- a/drivers/gpu/drm/drm_connector.c +++ b/drivers/gpu/drm/drm_connector.c @@ -1385,12 +1385,6 @@ EXPORT_SYMBOL(drm_mode_create_scaling_mo * * The driver may place further restrictions within these minimum * and maximum bounds. - * - * The semantics for the vertical blank timestamp differ when - * variable refresh rate is active. The vertical blank timestamp - * is defined to be an estimate using the current mode's fixed - * refresh rate timings. The semantics for the page-flip event - * timestamp remain the same. */ /**