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=-8.7 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 439D9C43613 for ; Thu, 20 Jun 2019 01:43:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 22FC9214AF for ; Thu, 20 Jun 2019 01:43:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731263AbfFTBnz (ORCPT ); Wed, 19 Jun 2019 21:43:55 -0400 Received: from mga01.intel.com ([192.55.52.88]:60110 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731198AbfFTBnv (ORCPT ); Wed, 19 Jun 2019 21:43:51 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga101.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 19 Jun 2019 18:43:50 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.63,394,1557212400"; d="scan'208";a="243484933" Received: from romley-ivt3.sc.intel.com ([172.25.110.60]) by orsmga001.jf.intel.com with ESMTP; 19 Jun 2019 18:43:50 -0700 From: Fenghua Yu To: "Thomas Gleixner" , "Ingo Molnar" , "Borislav Petkov" , "H Peter Anvin" , "Andy Lutomirski" , "Peter Zijlstra" , "Ashok Raj" , "Tony Luck" , "Ravi V Shankar" Cc: "linux-kernel" , "x86" , Fenghua Yu Subject: [PATCH v5 5/5] x86/umwait: Document umwait control sysfs interfaces Date: Wed, 19 Jun 2019 18:33:58 -0700 Message-Id: <1560994438-235698-6-git-send-email-fenghua.yu@intel.com> X-Mailer: git-send-email 2.5.0 In-Reply-To: <1560994438-235698-1-git-send-email-fenghua.yu@intel.com> References: <1560994438-235698-1-git-send-email-fenghua.yu@intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Since two new sysfs interface files are created for umwait control, add an ABI document entry for the files: /sys/devices/system/cpu/umwait_control/enable_c02 /sys/devices/system/cpu/umwait_control/max_time Signed-off-by: Fenghua Yu Reviewed-by: Ashok Raj --- .../ABI/testing/sysfs-devices-system-cpu | 21 +++++++++++++++++++ 1 file changed, 21 insertions(+) diff --git a/Documentation/ABI/testing/sysfs-devices-system-cpu b/Documentation/ABI/testing/sysfs-devices-system-cpu index 1528239f69b2..d22cdadd3161 100644 --- a/Documentation/ABI/testing/sysfs-devices-system-cpu +++ b/Documentation/ABI/testing/sysfs-devices-system-cpu @@ -538,3 +538,24 @@ Description: Intel Energy and Performance Bias Hint (EPB) This attribute is present for all online CPUs supporting the Intel EPB feature. + +What: /sys/devices/system/cpu/umwait_control + /sys/devices/system/cpu/umwait_control/enable_c02 + /sys/devices/system/cpu/umwait_control/max_time +Date: May 2019 +Contact: Linux kernel mailing list +Description: Umwait control + + enable_c02: Read/write interface to control umwait C0.2 state + Read returns C0.2 state status: + 0: C0.2 is disabled + 1: C0.2 is enabled + + Write 'Yy1' or [oO][nN] for on to enable C0.2 state. + Write 'Nn0' or [oO][fF] for off to disable C0.2 state. + + max_time: Read/write interface to control umwait maximum time + in TSC-quanta that the CPU can reside in either C0.1 + or C0.2 state. The time is an unsigned 32-bit number. + Note that a value of zero means there is no limit. + Low order two bits must be zero. -- 2.19.1