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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED 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 A1E91ECE560 for ; Mon, 17 Sep 2018 22:59:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 633042146F for ; Mon, 17 Sep 2018 22:59:29 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 633042146F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729783AbeIRE2x (ORCPT ); Tue, 18 Sep 2018 00:28:53 -0400 Received: from foss.arm.com ([217.140.101.70]:36866 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729026AbeIRE2x (ORCPT ); Tue, 18 Sep 2018 00:28:53 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 0C8EE7A9; Mon, 17 Sep 2018 15:59:26 -0700 (PDT) Received: from [192.168.100.242] (usa-sjc-mx-foss1.foss.arm.com [217.140.101.70]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 73E2A3F5C0; Mon, 17 Sep 2018 15:59:25 -0700 (PDT) Subject: Re: [PATCH v2 2/2] ACPI/PPTT: Handle architecturally unknown cache types To: Jeffrey Hugo , Sudeep Holla , gregkh@linuxfoundation.org, rjw@rjwysocki.net, linux-acpi@vger.kernel.org Cc: linux-kernel@vger.kernel.org, vkilari@codeaurora.org References: <1536942489-4018-1-git-send-email-jhugo@codeaurora.org> <1536942489-4018-3-git-send-email-jhugo@codeaurora.org> <71208e0e-fba9-ad6c-7578-a53fd1aa3f40@arm.com> <0a40d4e5-8b5b-dc6c-17e3-d6f02e396b2d@codeaurora.org> From: Jeremy Linton Message-ID: <4b50b3e9-55d7-67c7-dbaf-8bd7d7fb23a5@arm.com> Date: Mon, 17 Sep 2018 17:59:19 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.7.0 MIME-Version: 1.0 In-Reply-To: <0a40d4e5-8b5b-dc6c-17e3-d6f02e396b2d@codeaurora.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 09/17/2018 05:46 PM, Jeffrey Hugo wrote: > On 9/17/2018 10:17 AM, Sudeep Holla wrote: >> >> >> On 14/09/18 17:28, Jeffrey Hugo wrote: >>> The type of a cache might not be specified by architectural >>> mechanisms (ie >>> system registers), but its type might be specified in the PPTT.  In this >>> case, we should populate the type of the cache, rather than leave it >>> undefined. >>> >>> This fixes the issue where the cacheinfo driver will not populate sysfs >>> for such caches, resulting in the information missing from utilities >>> like >>> lstopo and lscpu, thus degrading the user experience. >>> >>> Fixes: 2bd00bcd73e5 (ACPI/PPTT: Add Processor Properties Topology >>> Table parsing) >>> Reported-by: Vijaya Kumar K >>> Signed-off-by: Jeffrey Hugo >>> --- >>>   drivers/acpi/pptt.c | 15 +++++++++++---- >>>   1 file changed, 11 insertions(+), 4 deletions(-) >>> >>> diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c >>> index d1e26cb..bb00ed9 100644 >>> --- a/drivers/acpi/pptt.c >>> +++ b/drivers/acpi/pptt.c >>> @@ -402,11 +402,18 @@ static void update_cache_properties(struct >>> cacheinfo *this_leaf, >>>           } >>>       } >>>       /* >>> -     * If the above flags are valid, and the cache type is NOCACHE >>> -     * update the cache type as well. >>> +     * If cache type is NOCACHE, then the cache hasn't been specified >>> +     * via other mechanisms.  Update the type if either the cache has >>> +     * been fully specified in PPTT, or a cache type has been provided. >>> +     * >>> +     * Note, we assume such caches are unified based on conventional >>> system >>> +     * design and known examples.  Significant work is required >>> elsewhere to >>> +     * fully support data/instruction only type caches which are only >>> +     * specified in PPTT. >>>        */ >>> -    if (this_leaf->type == CACHE_TYPE_NOCACHE && >>> -        valid_flags == PPTT_CHECKED_ATTRIBUTES) >>> +    if ((this_leaf->type == CACHE_TYPE_NOCACHE) && >>> +        (valid_flags == PPTT_CHECKED_ATTRIBUTES || >>> +         found_cache->flags & ACPI_PPTT_CACHE_TYPE_VALID)) >>>           this_leaf->type = CACHE_TYPE_UNIFIED; >> >> I thought I did mention that we can drop the valid_flags altogether >> unless Jeremy has reasons not to. >> > > You suggested that perhaps that could be the case.  It seemed like an > open question to me.  I'm at Linaro Connect without access to the device > this week, so I guess someone has roughly a week to chime in that the > valid flags should be kept, otherwise I'll try a v3 with them removed. > The point of the valid_flags/CHECKED_ATTRIBUTE was to help assure that a minimum set of attributes were being provided by the firmware. If we are going to reset the CACHE_TYPE, then we might as well remove the valid_flag/CHECKED_ATTRIBUTE counts as it can be easily bypassed. So, yes please, remove the valid_flags with this change. Thanks,