From patchwork Mon May 23 17:27:57 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: srinivas pandruvada X-Patchwork-Id: 575665 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 6D789C433EF for ; Mon, 23 May 2022 17:44:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241129AbiEWRoM (ORCPT ); Mon, 23 May 2022 13:44:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42306 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S242218AbiEWRhZ (ORCPT ); Mon, 23 May 2022 13:37:25 -0400 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 7BD4823150; Mon, 23 May 2022 10:31:10 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1653327070; x=1684863070; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=yEKxJVGCY27SHm5dP9lIMOmKkOGFlFMyVfaXYrGEgOA=; b=RKG5vLCn4NHSN0ULoje8CgbeSIYdoL1KJoT0CBSMYytoRuxF0YmwR+H6 D1bVmLCifpdthshBIGNMT2ohbycx+63KftIKeBdDeJ8pWcsb2kli88Ogc JV90jFUf2cYNhTxBq1LBq/BQOYj3e9K3mhExiGNtzphmkRdmubewzLtQ/ 5UdiilF60BqYdryKmob08gamuGFkxsx8/Km1NtJ1ibSa6gLWuoacUUwWf BWcPeZ2Z95xG6edF4JgctdxfGM1ZpyjbKASUjmOpZGTpyWarbYVFe52lt yfYpjrr/BYfY1OH13Llew0OMr5z2FiR3HAVocaEjX24ltLnE4mXr59rxG g==; X-IronPort-AV: E=McAfee;i="6400,9594,10356"; a="273290493" X-IronPort-AV: E=Sophos;i="5.91,246,1647327600"; d="scan'208";a="273290493" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 23 May 2022 10:28:24 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.91,246,1647327600"; d="scan'208";a="577510072" Received: from spandruv-desk.jf.intel.com ([10.54.75.8]) by fmsmga007.fm.intel.com with ESMTP; 23 May 2022 10:28:23 -0700 From: Srinivas Pandruvada To: rafael@kernel.org, corbet@lwn.net, hdegoede@redhat.com, markgross@kernel.org Cc: lenb@kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-doc@vger.kernel.org, platform-driver-x86@vger.kernel.org, prarit@redhat.com, Srinivas Pandruvada Subject: [PATCH] Documentation: admin-guide: pm: Add Out of Band mode Date: Mon, 23 May 2022 10:27:57 -0700 Message-Id: <20220523172757.2351052-1-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 Update documentation for using the tool to support performance level change via OOB (Out of Band) interface. Signed-off-by: Srinivas Pandruvada --- .../admin-guide/pm/intel-speed-select.rst | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/Documentation/admin-guide/pm/intel-speed-select.rst b/Documentation/admin-guide/pm/intel-speed-select.rst index 0a1fbdb54bfe..4146a2da35ea 100644 --- a/Documentation/admin-guide/pm/intel-speed-select.rst +++ b/Documentation/admin-guide/pm/intel-speed-select.rst @@ -262,6 +262,25 @@ Which shows that the base frequency now increased from 2600 MHz at performance level 0 to 2800 MHz at performance level 4. As a result, any workload, which can use fewer CPUs, can see a boost of 200 MHz compared to performance level 0. +Changing performance level via BMC Interface +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + +It is possible to change SST-PP level using out of band (OOB) agent (Via some +remote management console, through BMC "Baseboard Management Controller" +interface). This mode is supported from the Sapphire Rapids processor +generation. The kernel and tool change to support this mode is added to Linux +kernel version 5.18. To enable this feature, kernel config +"CONFIG_INTEL_HFI_THERMAL" is required. The minimum version of the tool +is "v1.12" to support this feature, which is part of Linux kernel version 5.18. + +To support such configuration, this tool can be used as a daemon. Add +a command line option --oob:: + +# intel-speed-select --oob + +In this mode the tool will online/offline CPUs based on the new performance +level. + Check presence of other Intel(R) SST features ---------------------------------------------