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 CCB4DC4345F for ; Tue, 16 Apr 2024 08:00:37 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 1636510F0E5; Tue, 16 Apr 2024 08:00:37 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="Tznqvtzm"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.12]) by gabe.freedesktop.org (Postfix) with ESMTPS id D767A10FFB3 for ; Tue, 16 Apr 2024 08:00:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1713254422; x=1744790422; h=from:to:cc:subject:in-reply-to:references:date: message-id:mime-version:content-transfer-encoding; bh=A0UhEo5CtF09GvzOkw7zbAoV5m2oDHhNGJgV61WOf2U=; b=TznqvtzmO3+KOmFeTH4F/cMhYgTAND431DSeC3xIzEqHhIUb+crq/PCY C6TEh3/QaH5TtebbyOCWzl7vIpVSrgeT9A8BESke9XbUWcvrDSrxLZ3x0 pcoisomKaleIeWn/8ddBXtTLMgRe6Nrwa5uMna0+TadiHpR3Bj2yWFrHJ KZPezJh/zfd0bWZOzfQxkvVqj819n0zz+DHCfxclkEv3BsWEoLQNv9mY3 CodQFBL5D8+9d6JsDN2FB2Rqlvtm1ciwpkd9IfusTsB0IE0xVTt42cC7o F1mrEzZhJ/wg9lc4X6ieWeG/r4128wjFRjirbDqnpvjB51M2yj9gWLctu A==; X-CSE-ConnectionGUID: eUNmxakcSC+aTAY6pgOmHA== X-CSE-MsgGUID: tswoI9NeTdW6V6gYR8jVvA== X-IronPort-AV: E=McAfee;i="6600,9927,11045"; a="12454241" X-IronPort-AV: E=Sophos;i="6.07,205,1708416000"; d="scan'208";a="12454241" Received: from orviesa010.jf.intel.com ([10.64.159.150]) by fmvoesa106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Apr 2024 01:00:16 -0700 X-CSE-ConnectionGUID: 9IuNJDEISWSvmZfPuQCU1g== X-CSE-MsgGUID: SUR9e7yIRD2yz6AAHl0MOQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.07,205,1708416000"; d="scan'208";a="22075952" Received: from martakit-mobl.ger.corp.intel.com (HELO localhost) ([10.252.44.100]) by orviesa010-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Apr 2024 01:00:15 -0700 From: Jani Nikula To: =?utf-8?Q?Jos=C3=A9?= Relvas , intel-gfx@lists.freedesktop.org Cc: "Shankar, Uma" Subject: Re: [REQUEST] Add support for Intel DPST (Display Power Saving Technology) In-Reply-To: Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo References: Date: Tue, 16 Apr 2024 11:00:12 +0300 Message-ID: <87sezlzqib.fsf@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Fri, 05 Apr 2024, Jos=C3=A9 Relvas wrote: > The best approach here would probably be to expose a similar attribute to= amdgpu's=20 > "panel_power_savings", with a scale that controls the feature's aggressiv= eness, > then update userspace tools, including power-profiles-daemon, to set the = value > based on the intended energy scheme. I don't really know what panel_power_savings does or how it works, but clearly it's not how this particular thing works on Intel hardware. There isn't a trivial knob you could adjust. Basically the goal is to reduce display brightness (and thus power consumption) based on display content with the high level idea of: reduced brightness, image enhancement params =3D fn(brightness, histogram) Where you have to add an API for reading the image histogram, add an API to set the image enhancement parameters, and how that function works is userspace policy that needs to be implemented in userspace. BR, Jani. --=20 Jani Nikula, Intel