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 DC5B2C43381 for ; Tue, 26 Mar 2019 22:39:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B391A2087C for ; Tue, 26 Mar 2019 22:39:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731868AbfCZWj4 (ORCPT ); Tue, 26 Mar 2019 18:39:56 -0400 Received: from foss.arm.com ([217.140.101.70]:44482 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726782AbfCZWjy (ORCPT ); Tue, 26 Mar 2019 18:39:54 -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 852C71596; Tue, 26 Mar 2019 15:39:54 -0700 (PDT) Received: from mammon-tx2.austin.arm.com (mammon-tx2.austin.arm.com [10.118.29.246]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E6DC03F614; Tue, 26 Mar 2019 15:39:53 -0700 (PDT) From: Jeremy Linton To: linux-arm-kernel@lists.infradead.org Cc: linux-acpi@vger.kernel.org, linux-kernel@vger.kernel.org, catalin.marinas@arm.com, will.deacon@arm.com, rjw@rjwysocki.net, lenb@kernel.org, mark.rutland@arm.com, sudeep.holla@arm.com, james.morse@arm.com, lorenzo.pieralisi@arm.com, linuxarm@huawei.com, Jeremy Linton Subject: [PATCH 1/4] ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens Date: Tue, 26 Mar 2019 17:39:35 -0500 Message-Id: <20190326223938.5365-2-jeremy.linton@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190326223938.5365-1-jeremy.linton@arm.com> References: <20190326223938.5365-1-jeremy.linton@arm.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org ACPI 6.3 adds a flag to indicate that child nodes are all identical cores. This is useful to authoritatively determine if a set of (possibly offline) cores are identical or not. Since the flag doesn't give us a unique id we can generate one and use it to create bitmaps of sibling nodes, or simply in a loop to determine if a subset of cores are identical. Signed-off-by: Jeremy Linton --- drivers/acpi/pptt.c | 26 ++++++++++++++++++++++++++ include/linux/acpi.h | 5 +++++ 2 files changed, 31 insertions(+) diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index 065c4fc245d1..472c95ec816b 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -660,3 +660,29 @@ int find_acpi_cpu_topology_package(unsigned int cpu) return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE, ACPI_PPTT_PHYSICAL_PACKAGE); } + +/** + * find_acpi_cpu_topology_hetero_id() - Determine a unique implementation + * @cpu: Kernel logical cpu number + * + * Determine a unique heterogeneous ID for the given CPU. CPUs with the same + * implementation should have matching IDs. Since this is a tree we can only + * detect implementations where the heterogeneous flag is the parent to all + * matching cores. AKA if a two socket machine has two different core types + * in each socket this will end up being represented as four unique core types + * rather than two. + * + * The returned ID can be used to group peers with identical implementation. + * + * The search terminates when a level is found with the identical implementation + * flag set or we reach a root node. + * + * Return: -ENOENT if the PPTT doesn't exist, or the cpu cannot be found. + * Otherwise returns a value which represents a group of identical cores + * similar to this cpu. + */ +int find_acpi_cpu_topology_hetero_id(unsigned int cpu) +{ + return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE, + ACPI_PPTT_ACPI_IDENTICAL); +} diff --git a/include/linux/acpi.h b/include/linux/acpi.h index d5dcebd7aad3..1444fb042898 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1309,6 +1309,7 @@ static inline int lpit_read_residency_count_address(u64 *address) #ifdef CONFIG_ACPI_PPTT int find_acpi_cpu_topology(unsigned int cpu, int level); int find_acpi_cpu_topology_package(unsigned int cpu); +int find_acpi_cpu_topology_hetero_id(unsigned int cpu); int find_acpi_cpu_cache_topology(unsigned int cpu, int level); #else static inline int find_acpi_cpu_topology(unsigned int cpu, int level) @@ -1319,6 +1320,10 @@ static inline int find_acpi_cpu_topology_package(unsigned int cpu) { return -EINVAL; } +static int find_acpi_cpu_topology_hetero_id(unsigned int cpu) +{ + return -EINVAL; +} static inline int find_acpi_cpu_cache_topology(unsigned int cpu, int level) { return -EINVAL; -- 2.20.1