From patchwork Thu Oct 27 22:00:56 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Srinivas Pandruvada X-Patchwork-Id: 619437 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 86706ECAAA1 for ; Thu, 27 Oct 2022 22:01:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234802AbiJ0WBp (ORCPT ); Thu, 27 Oct 2022 18:01:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54470 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234800AbiJ0WBX (ORCPT ); Thu, 27 Oct 2022 18:01:23 -0400 Received: from mga05.intel.com (mga05.intel.com [192.55.52.43]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BBAF49E688; Thu, 27 Oct 2022 15:00:59 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1666908060; x=1698444060; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=fujCfldGBPIDZRrZhsgY+3RvDLnevLWFmVpeF8wnuOo=; b=aFT3EVIWxlGtAs6snjxocbyCOqULwuuxpkcWu9D8j2dXtQecjvO9bkG6 BURWLTRRjLKB1MZ9hxzy/GqtRSOKYcvDmm+F+hyHaCgMORkKetI25wyoV jfg6IthJAwW5x3HnNWgx1cw+DVKusfdAurgGI1oTcszDOhNIoATbZjMqg aROsSb/rcdME6XK1ePLPKRrRJdbboWI1KBclAaByExvX0WbGewMVBI5Io XYygRXrLh1TH8KwHBDPqgtVkqSVCVwNno3LHKWOkdNTyl4VyhnYWkLR1+ deAukGLztTWzmKKfHzCroux8W4XzRewft9KVShpRpgz6qOBydFWNtKRkP A==; X-IronPort-AV: E=McAfee;i="6500,9779,10513"; a="394665997" X-IronPort-AV: E=Sophos;i="5.95,219,1661842800"; d="scan'208";a="394665997" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Oct 2022 15:00:58 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10513"; a="635071032" X-IronPort-AV: E=Sophos;i="5.95,219,1661842800"; d="scan'208";a="635071032" Received: from spandruv-desk.jf.intel.com ([10.54.75.8]) by fmsmga007.fm.intel.com with ESMTP; 27 Oct 2022 15:00:58 -0700 From: Srinivas Pandruvada To: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, hpa@zytor.com, rafael@kernel.org, len.brown@intel.com Cc: peterz@infradead.org, x86@kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, Srinivas Pandruvada Subject: [PATCH] x86: intel_epb: Set Alder Lake N and Raptor Lake P normal EPB Date: Thu, 27 Oct 2022 15:00:56 -0700 Message-Id: <20221027220056.1534264-1-srinivas.pandruvada@linux.intel.com> X-Mailer: git-send-email 2.31.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Intel processors support additional software hint called EPB ("Energy Performance Bias") to guide the hardware heuristic of power management features to favor increasing dynamic performance or conserve energy consumption. Since this EPB hint is processor specific, the same value of hint can result in different behavior across generations of processors. commit 4ecc933b7d1f ("x86: intel_epb: Allow model specific normal EPB value")' introduced capability to update the default power up EPB based on the CPU model and updated the default EPB to 7 for Alder Lake mobile CPUs. The same change is required for other Alder Lake-N and Raptor Lake-P mobile CPUs as the current default of 6 results in higher uncore power consumption. This increase in power is related to memory clock frequency setting based on the EPB value. Depending on the EPB the minimum memory frequency is set by the firmware. At EPB = 7, the minimum memory frequency is 1/4th compared to EPB = 6. This results in significant power saving for idle and semi-idle workload on a Chrome platform. For example Change in power and performance from EPB change from 6 to 7 on Alder Lake-N: Workload Performance diff (%) power diff ---------------------------------------------------- VP9 FHD30 0 (FPS) -218 mw Google meet 0 (FPS) -385 mw This 200+ mw power saving is very significant for mobile platform for battery life and thermal reasons. But as the workload demands more memory bandwidth, the memory frequency will be increased very fast. There is no power savings for such busy workloads. For example: Workload Performance diff (%) from EPB 6 to 7 ------------------------------------------------------- Speedometer 2.0 -0.8 WebGL Aquarium 10K Fish -0.5 Unity 3D 2018 0.2 WebXPRT3 -0.5 There are run to run variations for performance scores for such busy workloads. So the difference is not significant. Add a new define ENERGY_PERF_BIAS_NORMAL_POWERSAVE for EPB 7 and use it for Alder Lake-N and Raptor Lake-P mobile CPUs. This modification is done originally by Jeremy Compostella . Signed-off-by: Srinivas Pandruvada Reviewed-by: Rafael J. Wysocki --- arch/x86/include/asm/msr-index.h | 1 + arch/x86/kernel/cpu/intel_epb.c | 7 ++++++- 2 files changed, 7 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/msr-index.h b/arch/x86/include/asm/msr-index.h index 10ac52705892..a3eb4d3e70b8 100644 --- a/arch/x86/include/asm/msr-index.h +++ b/arch/x86/include/asm/msr-index.h @@ -796,6 +796,7 @@ #define ENERGY_PERF_BIAS_PERFORMANCE 0 #define ENERGY_PERF_BIAS_BALANCE_PERFORMANCE 4 #define ENERGY_PERF_BIAS_NORMAL 6 +#define ENERGY_PERF_BIAS_NORMAL_POWERSAVE 7 #define ENERGY_PERF_BIAS_BALANCE_POWERSAVE 8 #define ENERGY_PERF_BIAS_POWERSAVE 15 diff --git a/arch/x86/kernel/cpu/intel_epb.c b/arch/x86/kernel/cpu/intel_epb.c index fbaf12e43f41..3b8476158236 100644 --- a/arch/x86/kernel/cpu/intel_epb.c +++ b/arch/x86/kernel/cpu/intel_epb.c @@ -204,7 +204,12 @@ static int intel_epb_offline(unsigned int cpu) } static const struct x86_cpu_id intel_epb_normal[] = { - X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE_L, 7), + X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE_L, + ENERGY_PERF_BIAS_NORMAL_POWERSAVE), + X86_MATCH_INTEL_FAM6_MODEL(ALDERLAKE_N, + ENERGY_PERF_BIAS_NORMAL_POWERSAVE), + X86_MATCH_INTEL_FAM6_MODEL(RAPTORLAKE_P, + ENERGY_PERF_BIAS_NORMAL_POWERSAVE), {} };