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 2B54CC41535 for ; Tue, 19 Dec 2023 10:05:30 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 9F95C10E44A; Tue, 19 Dec 2023 10:05:29 +0000 (UTC) Received: from mgamail.intel.com (mgamail.intel.com [192.55.52.115]) by gabe.freedesktop.org (Postfix) with ESMTPS id 506B210E44A for ; Tue, 19 Dec 2023 10:05:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1702980328; x=1734516328; h=from:to:subject:in-reply-to:references:date:message-id: mime-version; bh=GYh2QAC0fStEzODabV1bQJMw123SDu7m97yVaq82oLY=; b=h2qmnm3EyZhY8zLqKkAjHFnw3nTGjv5yYDnV5HvQMW1Xx7RFQm/1Gcu3 WJoUvDr9VXIp5XEWedNn4xGxzzpxM60ZRRui3GzTpbvo7BnePc97F4Qsj vGkaR2fC5Bn4oPRrb93yDJ1t7dQDgGNApRbLJn3xhrp+8mTeYLgyqLkc7 T7ErXRGfQEm4ccHpz1gmjSPb66dZs46smoeq579ORcFBnOSgp95Zd3gIL Zj+7d2vNBKji7rzWE/+cAIHGly9gz+ky1SpVR20uquDz62eHh1xkB6yRq ig096f3OZo/zD59rtAbN4vlKhnhIDBX5CUqM/CotIL60vC2/ex0kIqyd4 w==; X-IronPort-AV: E=McAfee;i="6600,9927,10928"; a="395366632" X-IronPort-AV: E=Sophos;i="6.04,287,1695711600"; d="scan'208";a="395366632" Received: from orviesa001.jf.intel.com ([10.64.159.141]) by fmsmga103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Dec 2023 02:05:27 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.04,287,1695711600"; d="scan'208";a="24131363" Received: from alexeyze-mobl.ger.corp.intel.com (HELO localhost) ([10.252.34.118]) by smtpauth.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 19 Dec 2023 02:05:25 -0800 From: Jani Nikula To: Thomas , dri-devel@lists.freedesktop.org Subject: Re: enforce the Display Stream Compression In-Reply-To: <494cba52-2a19-e2dd-8a88-bc304f729889@web.de> Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: <494cba52-2a19-e2dd-8a88-bc304f729889@web.de> Date: Tue, 19 Dec 2023 12:05:22 +0200 Message-ID: <87sf3ytsm5.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, 18 Dec 2023, Thomas wrote: > I want to enforce the Display Stream Compression (DSC) of the Intel i915 > driver in Linux Ubuntu 22.04 to test it. While inspecting the source > code, I came across a query called "force_dsc_output_format" that seems > useful to me. My question is more general and pertains to the procedure > for setting such queries/switches. How can I set this query to True to > force DSC? Do I need to modify the kernel parameter line, and if so, > how? Or is there another method? There are connector debugfs files named i915_dsc_* for controlling this. They are for debug and test purposes only. See the relevant igt tests for how they're used in testing [1]. BR, Jani. [1] https://gitlab.freedesktop.org/drm/igt-gpu-tools -- Jani Nikula, Intel