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=-6.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT 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 EA119C433ED for ; Mon, 3 May 2021 18:08:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C53106135F for ; Mon, 3 May 2021 18:08:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231955AbhECSJo (ORCPT ); Mon, 3 May 2021 14:09:44 -0400 Received: from srv6.fidu.org ([159.69.62.71]:56098 "EHLO srv6.fidu.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232064AbhECSJZ (ORCPT ); Mon, 3 May 2021 14:09:25 -0400 Received: from localhost (localhost.localdomain [127.0.0.1]) by srv6.fidu.org (Postfix) with ESMTP id 3E51CC800D0; Mon, 3 May 2021 20:08:29 +0200 (CEST) X-Virus-Scanned: Debian amavisd-new at srv6.fidu.org Received: from srv6.fidu.org ([127.0.0.1]) by localhost (srv6.fidu.org [127.0.0.1]) (amavisd-new, port 10026) with LMTP id lYnKtLw43Eeq; Mon, 3 May 2021 20:08:29 +0200 (CEST) Received: from wsembach-tuxedo.fritz.box (p200300e37F3986001a8b79e0b24Cb29D.dip0.t-ipconnect.de [IPv6:2003:e3:7f39:8600:1a8b:79e0:b24c:b29d]) (Authenticated sender: wse@tuxedocomputers.com) by srv6.fidu.org (Postfix) with ESMTPA id C8427C800CE; Mon, 3 May 2021 20:08:28 +0200 (CEST) From: Werner Sembach To: wse@tuxedocomputers.com, ville.syrjala@linux.intel.com, airlied@linux.ie, daniel@ffwll.ch, intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: [PATCH 0/4] drm/i915/display Try YCbCr420 color when RGB fails Date: Mon, 3 May 2021 20:08:07 +0200 Message-Id: <20210503180810.851302-1-wse@tuxedocomputers.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org When encoder validation of a display mode fails, retry with less bandwidth heavy YCbCr420 color mode, if available. This enables some HDMI 1.4 setups to support 4k60Hz output, which previously failed silently. AMDGPU had nearly the exact same issue. This problem description is therefore copied from my commit message of the AMDGPU patch. On some setups, while the monitor and the gpu support display modes with pixel clocks of up to 600MHz, the link encoder might not. This prevents YCbCr444 and RGB encoding for 4k60Hz, but YCbCr420 encoding might still be possible. However, which color mode is used is decided before the link encoder capabilities are checked. This patch fixes the problem by retrying to find a display mode with YCbCr420 enforced and using it, if it is valid. This patchset is revision 2, now split up in multiple parts with some minor restructuring added für a cleaner implementation.