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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 637E9C05027 for ; Fri, 3 Feb 2023 14:03:04 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id AE05C10E7A3; Fri, 3 Feb 2023 14:02:59 +0000 (UTC) Received: from mga14.intel.com (mga14.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 5DED510E059; Fri, 3 Feb 2023 14:02:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1675432977; x=1706968977; h=date:from:to:cc:subject:message-id:references: mime-version:content-transfer-encoding:in-reply-to; bh=irv3lGzYjgRrPupsMvPPq8fHSBpnLKmUkKwUr8MxDSE=; b=hjD1qntADYKQ1Us+Y+xLmbLv7ZwN3JkH6okpugshN5IP3UMPEYNpwoou Alw8qD0WF4Tqs3vk6rMQSprhNHBqkIF+VVN2gQ5RzhFcxqHhnxJIYyuM1 ar5o69kA1CShPQ5/6CJRRdA0zFVmiMh1WwrgpGY4PPgg3UAAYmBVmYVZV os3NI1JRLxKLJDuqBfy7MK2HpIRf1U7xDYW8v04gueVGvyxDbFAOtKaNQ nx8ilGa6ukmnzr2e2cteZ2LWHIpyAzB1UUg9+qk59LC2CO+wMUqj+P3BL Zka4mjj6acxQyQ0pZTlY0rabI60DEnslXjR2tCcdBTpVZDD7cMlWZy1J9 g==; X-IronPort-AV: E=McAfee;i="6500,9779,10610"; a="328767145" X-IronPort-AV: E=Sophos;i="5.97,270,1669104000"; d="scan'208";a="328767145" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Feb 2023 06:02:56 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10610"; a="665726345" X-IronPort-AV: E=Sophos;i="5.97,270,1669104000"; d="scan'208";a="665726345" Received: from stinkpipe.fi.intel.com (HELO stinkbox) ([10.237.72.55]) by orsmga002.jf.intel.com with SMTP; 03 Feb 2023 06:02:53 -0800 Received: by stinkbox (sSMTP sendmail emulation); Fri, 03 Feb 2023 16:02:51 +0200 Date: Fri, 3 Feb 2023 16:02:51 +0200 From: Ville =?iso-8859-1?Q?Syrj=E4l=E4?= To: Sebastian Wick Subject: Re: [PATCH 3/3] drm/connector: Deprecate split for BT.2020 in drm_colorspace enum Message-ID: References: <20230203020744.30745-1-joshua@froggi.es> <20230203020744.30745-3-joshua@froggi.es> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-Patchwork-Hint: comment X-BeenThere: amd-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Discussion list for AMD gfx List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: amd-gfx@lists.freedesktop.org, Pekka Paalanen , Uma Shankar , dri-devel@lists.freedesktop.org, Joshua Ashton , Vitaly.Prosyak@amd.com Errors-To: amd-gfx-bounces@lists.freedesktop.org Sender: "amd-gfx" On Fri, Feb 03, 2023 at 02:52:50PM +0100, Sebastian Wick wrote: > On Fri, Feb 3, 2023 at 2:35 PM Ville Syrjälä > wrote: > > > > On Fri, Feb 03, 2023 at 01:59:07PM +0100, Sebastian Wick wrote: > > > On Fri, Feb 3, 2023 at 11:40 AM Ville Syrjälä > > > wrote: > > > > > > > > On Fri, Feb 03, 2023 at 02:07:44AM +0000, Joshua Ashton wrote: > > > > > Userspace has no way of controlling or knowing the pixel encoding > > > > > currently, so there is no way for it to ever get the right values here. > > > > > > > > That applies to a lot of the other values as well (they are > > > > explicitly RGB or YCC). The idea was that this property sets the > > > > infoframe/MSA/SDP value exactly, and other properties should be > > > > added to for use userspace to control the pixel encoding/colorspace > > > > conversion(if desired, or userspace just makes sure to > > > > directly feed in correct kind of data). > > > > > > I'm all for getting userspace control over pixel encoding but even > > > then the kernel always knows which pixel encoding is selected and > > > which InfoFrame has to be sent. Is there a reason why userspace would > > > want to control the variant explicitly to the wrong value? > > > > What do you mean wrong value? Userspace sets it based on what > > kind of data it has generated (or asked the display hardware > > to generate if/when we get explicit control over that part). > > Wrong in the sense of sending the YCC variant when the pixel encoding > is RGB for example. > > Maybe I'm missing something here but my assumption is that the kernel > always has to know the pixel encoding anyway. The color pipeline also > assumes that the pixel values are RGB. User space might be able to > generate YCC content but for subsampling etc the pixel encoding still > has to be explicitly set. The kernel doesn't really know much atm. In theory you can just configure the thing to do a straight passthough and put anything you want into your pixels. > > So with the kernel always knowing exactly what pixel encoding is sent, > why do we need those variants? I just don't see why this is necessary. > > > > > -- > > Ville Syrjälä > > Intel > > -- Ville Syrjälä Intel