From patchwork Thu Nov 9 21:03:08 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeremy Linton X-Patchwork-Id: 10051913 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 999CC60631 for ; Thu, 9 Nov 2017 21:04:56 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8DC7F2AC77 for ; Thu, 9 Nov 2017 21:04:56 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 829632AD64; Thu, 9 Nov 2017 21:04:56 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0FFBE2AC77 for ; Thu, 9 Nov 2017 21:04:56 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753917AbdKIVEj (ORCPT ); Thu, 9 Nov 2017 16:04:39 -0500 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:51742 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754728AbdKIVDj (ORCPT ); Thu, 9 Nov 2017 16:03:39 -0500 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 4879D1684; Thu, 9 Nov 2017 13:03:39 -0800 (PST) Received: from beelzebub.austin.arm.com (beelzebub.austin.arm.com [10.118.12.119]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 4819A3F3DF; Thu, 9 Nov 2017 13:03:38 -0800 (PST) From: Jeremy Linton To: linux-acpi@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, sudeep.holla@arm.com, hanjun.guo@linaro.org, lorenzo.pieralisi@arm.com, rjw@rjwysocki.net, will.deacon@arm.com, catalin.marinas@arm.com, gregkh@linuxfoundation.org, viresh.kumar@linaro.org, mark.rutland@arm.com, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, jhugo@codeaurora.org, wangxiongfeng2@huawei.com, Jonathan.Zhang@cavium.com, ahs3@redhat.com, Jayachandran.Nair@cavium.com, austinwc@codeaurora.org, lenb@kernel.org, robert.moore@intel.com, lv.zheng@intel.com, devel@acpica.org, Jeremy Linton Subject: [PATCH v4 6/9] ACPI/PPTT: Add topology parsing code Date: Thu, 9 Nov 2017 15:03:08 -0600 Message-Id: <20171109210311.25655-7-jeremy.linton@arm.com> X-Mailer: git-send-email 2.13.5 In-Reply-To: <20171109210311.25655-1-jeremy.linton@arm.com> References: <20171109210311.25655-1-jeremy.linton@arm.com> Sender: linux-pm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The PPTT can be used to determine the groupings of CPU's at given levels in the system. Lets add a few routines to the PPTT parsing code to return a unique id for each unique level in the processor hierarchy. This can then be matched to build thread/core/cluster/die/package/etc mappings for each processing element in the system. Signed-off-by: Jeremy Linton --- drivers/acpi/pptt.c | 117 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 117 insertions(+) diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index aa259502c4eb..b629d0b9a3a0 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -388,6 +388,81 @@ static void cache_setup_acpi_cpu(struct acpi_table_header *table, } } +/* + * Passing level values greater than this will result in search termination + */ +#define PPTT_ABORT_PACKAGE 0xFF + +/* + * Given a acpi_pptt_processor node, walk up until we identify the + * package that the node is associated with, or we run out of levels + * to request or the search is terminated with a flag match + * The level parameter also serves to limit possible loops within the tree. + */ +static struct acpi_pptt_processor *acpi_find_processor_package_id( + struct acpi_table_header *table_hdr, + struct acpi_pptt_processor *cpu, + int level, int flag) +{ + struct acpi_pptt_processor *prev_node; + + while (cpu && level) { + if (cpu->flags & flag) + break; + pr_debug("level %d\n", level); + prev_node = fetch_pptt_node(table_hdr, cpu->parent); + if (prev_node == NULL) + break; + cpu = prev_node; + level--; + } + return cpu; +} + +/* + * Get a unique value given a cpu, and a topology level, that can be + * matched to determine which cpus share common topological features + * at that level. + */ +static int topology_get_acpi_cpu_tag(struct acpi_table_header *table, + unsigned int cpu, int level, int flag) +{ + struct acpi_pptt_processor *cpu_node; + u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); + + cpu_node = acpi_find_processor_node(table, acpi_cpu_id); + if (cpu_node) { + cpu_node = acpi_find_processor_package_id(table, cpu_node, + level, flag); + /* Only the first level has a guaranteed id */ + if (level == 0) + return cpu_node->acpi_processor_id; + return (int)((u8 *)cpu_node - (u8 *)table); + } + pr_err_once("PPTT table found, but unable to locate core for %d\n", + cpu); + return -ENOENT; +} + +static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag) +{ + struct acpi_table_header *table; + acpi_status status; + int retval; + + status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); + if (ACPI_FAILURE(status)) { + pr_err_once("No PPTT table found, cpu topology may be inaccurate\n"); + return -ENOENT; + } + retval = topology_get_acpi_cpu_tag(table, cpu, level, flag); + pr_debug("Topology Setup ACPI cpu %d, level %d ret = %d\n", + cpu, level, retval); + acpi_put_table(table); + + return retval; +} + /** * acpi_find_last_cache_level() - Determines the number of cache levels for a PE * @cpu: Kernel logical cpu number @@ -451,3 +526,45 @@ int cache_setup_acpi(unsigned int cpu) return status; } + +/** + * find_acpi_cpu_topology() - Determine a unique topology value for a given cpu + * @cpu: Kernel logical cpu number + * @level: The topological level for which we would like a unique ID + * + * Determine a topology unique ID for each thread/core/cluster/mc_grouping + * /socket/etc. This ID can then be used to group peers, which will have + * matching ids. + * + * The search terminates when either the requested level is found or + * we reach a root node. Levels beyond the termination point will return the + * same unique ID. The unique id for level 0 is the acpi processor id. All + * other levels beyond this use a generated value to uniquely identify + * a topological feature. + * + * Return: -ENOENT if the PPTT doesn't exist, or the cpu cannot be found. + * Otherwise returns a value which represents a unique topological feature. + */ +int find_acpi_cpu_topology(unsigned int cpu, int level) +{ + return find_acpi_cpu_topology_tag(cpu, level, 0); +} + +/** + * find_acpi_cpu_topology_package() - Determine a unique cpu package value + * @cpu: Kernel logical cpu number + * + * Determine a topology unique package ID for the given cpu. + * This ID can then be used to group peers, which will have matching ids. + * + * The search terminates when either a level is found with the PHYSICAL_PACKAGE + * 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 the package for this cpu. + */ +int find_acpi_cpu_topology_package(unsigned int cpu) +{ + return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE, + ACPI_PPTT_PHYSICAL_PACKAGE); +}