From patchwork Tue May 17 22:24:28 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Chang S. Bae" X-Patchwork-Id: 573609 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 E75D6C433F5 for ; Tue, 17 May 2022 22:33:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231243AbiEQWdU (ORCPT ); Tue, 17 May 2022 18:33:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44356 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230494AbiEQWdU (ORCPT ); Tue, 17 May 2022 18:33:20 -0400 Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 170443EABA; Tue, 17 May 2022 15:33:19 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1652826799; x=1684362799; h=from:to:cc:subject:date:message-id; bh=ktE04coO5bw2iUMOgThFEuycIpP9WgRpewz8e7wF3Ys=; b=dfFpUQCmdF+GPbwA+qeu7CA4BJ00tDcbpZRk9McNav+96Js1WM9JVnfT TpxVtjn4cV0iLEuqp2BT+nDijmh1GNva/EF0jfGLBSAz9RGIACFddb5Ld 9ohNFqRvxT9japi5phaJLa9Tb0zJcHwrmoOaZ7TKI2JAuJmkFx4DnI3Nd VjoN8IV/MkieWvfONYogISW63T3Uo4gVuQ1MvZtK2doB6FMDK7fB4slFf 2GqTL7LCiPMv5IljxhkCmMLc/KCT4tCfDQORkbHEBPSZmd7dxJaEz5f6J fJ6YmjQIqdG8Ri+0ePJYDf7VZnhUK52Fuq3GHYrjGXiyaPdNPRpl9roKA w==; X-IronPort-AV: E=McAfee;i="6400,9594,10350"; a="268945486" X-IronPort-AV: E=Sophos;i="5.91,233,1647327600"; d="scan'208";a="268945486" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 May 2022 15:33:18 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.91,233,1647327600"; d="scan'208";a="555993791" Received: from chang-linux-3.sc.intel.com ([172.25.66.173]) by orsmga002.jf.intel.com with ESMTP; 17 May 2022 15:33:18 -0700 From: "Chang S. Bae" To: linux-kernel@vger.kernel.org, x86@kernel.org, linux-pm@vger.kernel.org Cc: tglx@linutronix.de, dave.hansen@linux.intel.com, peterz@infradead.org, bp@alien8.de, rafael@kernel.org, ravi.v.shankar@intel.com, chang.seok.bae@intel.com Subject: [PATCH v4 0/2] x86/fpu: Make AMX state ready for CPU idle Date: Tue, 17 May 2022 15:24:28 -0700 Message-Id: <20220517222430.24524-1-chang.seok.bae@intel.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org Hi, First of all, my apologies for the long delay with my vacation. Changes from v3 [1]: * Call out AMX state only needs to be initialized for CPU idle (Thomas). * Drop the XCR0 accessor changes as not relevant (Dave). The series is available here: git://github.com/intel/amx-linux.git tilerelease === Original Cover Letter === AMX state is a large state (at least 8KB or more). Entering CPU idle with this non-initialized large state may result in shallow states while a deeper low-power state is available. We can confirm this behavior is implementation-specific. Section 3.3 in [2] will be updated to clarify this. Thanks, Chang [1]: https://lore.kernel.org/lkml/20220325022219.829-1-chang.seok.bae@intel.com/ [2]: Intel Architecture Instruction Set Extension Programming Reference May 2021, https://software.intel.com/content/dam/develop/external/us/en/documents-tps/architecture-instruction-set-extensions-programming-reference.pdf Chang S. Bae (2): x86/fpu: Add a helper to prepare AMX state for low-power CPU idle intel_idle: Add a new flag to initialize the AMX state arch/x86/include/asm/fpu/api.h | 2 ++ arch/x86/include/asm/special_insns.h | 9 +++++++++ arch/x86/kernel/fpu/core.c | 13 +++++++++++++ drivers/idle/intel_idle.c | 18 ++++++++++++++++-- 4 files changed, 40 insertions(+), 2 deletions(-) base-commit: 42226c989789d8da4af1de0c31070c96726d990c