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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 22819C43381 for ; Mon, 25 Mar 2019 16:04:45 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EEC6620830 for ; Mon, 25 Mar 2019 16:04:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729704AbfCYQEo (ORCPT ); Mon, 25 Mar 2019 12:04:44 -0400 Received: from mga11.intel.com ([192.55.52.93]:30362 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725747AbfCYQEm (ORCPT ); Mon, 25 Mar 2019 12:04:42 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga002.jf.intel.com ([10.7.209.21]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 25 Mar 2019 09:04:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.60,269,1549958400"; d="scan'208";a="145078749" Received: from spandruv-mobl.jf.intel.com ([10.24.11.149]) by orsmga002.jf.intel.com with ESMTP; 25 Mar 2019 09:04:40 -0700 From: Srinivas Pandruvada To: rjw@rjwysocki.net, lenb@kernel.org, viresh.kumar@linaro.org Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, pprakash@codeaurora.org, wangxiongfeng2@huawei.com, srinivas.pandruvada@linux.intel.com Subject: [PATCH v2 1/2] ACPI / CPPC: Fix processing for guaranteed performance Date: Mon, 25 Mar 2019 09:04:39 -0700 Message-Id: <20190325160440.7575-2-srinivas.pandruvada@linux.intel.com> X-Mailer: git-send-email 2.17.2 In-Reply-To: <20190325160440.7575-1-srinivas.pandruvada@linux.intel.com> References: <20190325160440.7575-1-srinivas.pandruvada@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As per ACPI specification "Guaranteed Performance Register" is a "Buffer" field. It can't be "Integer" field. So treat "Integer" type as invalid and ignore "Guaranteed Performance Register". Also save one cpc_read() call, when "Guaranteed Performance Register" is not present, which means register defined as: "Register(SystemMemory, 0, 0, 0, 0)". Fixes: 29523f095397 ("ACPI / CPPC: Add support for guaranteed performance") Suggested-by: Rafael J. Wysocki Signed-off-by: Srinivas Pandruvada Cc: 4.20+ # 4.20+ --- drivers/acpi/cppc_acpi.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/drivers/acpi/cppc_acpi.c b/drivers/acpi/cppc_acpi.c index 1b207fca1420..d4244e7d0e38 100644 --- a/drivers/acpi/cppc_acpi.c +++ b/drivers/acpi/cppc_acpi.c @@ -1150,8 +1150,13 @@ int cppc_get_perf_caps(int cpunum, struct cppc_perf_caps *perf_caps) cpc_read(cpunum, nominal_reg, &nom); perf_caps->nominal_perf = nom; - cpc_read(cpunum, guaranteed_reg, &guaranteed); - perf_caps->guaranteed_perf = guaranteed; + if (guaranteed_reg->type != ACPI_TYPE_BUFFER || + IS_NULL_REG(&guaranteed_reg->cpc_entry.reg)) { + perf_caps->guaranteed_perf = 0; + } else { + cpc_read(cpunum, guaranteed_reg, &guaranteed); + perf_caps->guaranteed_perf = guaranteed; + } cpc_read(cpunum, lowest_non_linear_reg, &min_nonlinear); perf_caps->lowest_nonlinear_perf = min_nonlinear; -- 2.17.2