From patchwork Fri Jun 28 18:14:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeremy Linton X-Patchwork-Id: 11023001 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id DBE511922 for ; Fri, 28 Jun 2019 18:20:29 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D270F28B7C for ; Fri, 28 Jun 2019 18:15:06 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C54AB28B80; Fri, 28 Jun 2019 18:15:06 +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=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham 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 5478F28B7C for ; Fri, 28 Jun 2019 18:15:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726672AbfF1SPG (ORCPT ); Fri, 28 Jun 2019 14:15:06 -0400 Received: from foss.arm.com ([217.140.110.172]:53260 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726667AbfF1SPF (ORCPT ); Fri, 28 Jun 2019 14:15:05 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5D7812B; Fri, 28 Jun 2019 11:15:05 -0700 (PDT) Received: from mammon-tx2.austin.arm.com (mammon-tx2.austin.arm.com [10.118.30.49]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 556403F718; Fri, 28 Jun 2019 11:15:05 -0700 (PDT) From: Jeremy Linton To: linux-arm-kernel@lists.infradead.org Cc: linux-acpi@vger.kernel.org, catalin.marinas@arm.com, will.deacon@arm.com, rjw@rjwysocki.net, lenb@kernel.org, lorenzo.pieralisi@arm.com, sudeep.holla@arm.com, Jeremy Linton Subject: [PATCH v3 1/2] ACPI/PPTT: Add support for ACPI 6.3 thread flag Date: Fri, 28 Jun 2019 13:14:56 -0500 Message-Id: <20190628181457.6609-2-jeremy.linton@arm.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190628181457.6609-1-jeremy.linton@arm.com> References: <20190628181457.6609-1-jeremy.linton@arm.com> MIME-Version: 1.0 Sender: linux-acpi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-acpi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP ACPI 6.3 adds a flag to the CPU node to indicate whether the given PE is a thread. Add a function to return that information for a given linux logical CPU. Signed-off-by: Jeremy Linton --- drivers/acpi/pptt.c | 62 +++++++++++++++++++++++++++++++++++++++++++- include/linux/acpi.h | 5 ++++ 2 files changed, 66 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index b72e6afaa8fb..bb6196422fad 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -517,6 +517,52 @@ static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag) return retval; } +/** + * check_acpi_cpu_flag() - Determine if CPU node has a flag set + * @cpu: Kernel logical CPU number + * @rev: The PPTT revision defining the flag + * @flag: The flag itself + * + * Check the node representing a CPU for a given flag. + * + * Return: -ENOENT if the PPTT doesn't exist, the CPU cannot be found or + * the table revision isn't new enough. + * 1, any passed flag set + * 0, flag unset + */ +static int check_acpi_cpu_flag(unsigned int cpu, int rev, u32 flag) +{ + struct acpi_table_header *table; + acpi_status status; + u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); + struct acpi_pptt_processor *cpu_node = NULL; + int ret = -ENOENT; + static int saved_pptt_rev = -1; + + /* Cache the PPTT revision to avoid repeat table get/put on failure */ + if (saved_pptt_rev > -1 && saved_pptt_rev < rev) + return -ENOENT; + + status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); + if (ACPI_FAILURE(status)) { + saved_pptt_rev = 0; + acpi_pptt_warn_missing(); + return ret; + } + + saved_pptt_rev = table->revision; + + if (saved_pptt_rev >= rev) + cpu_node = acpi_find_processor_node(table, acpi_cpu_id); + + if (cpu_node) + ret = (cpu_node->flags & flag) != 0; + + acpi_put_table(table); + + return ret; +} + /** * acpi_find_last_cache_level() - Determines the number of cache levels for a PE * @cpu: Kernel logical CPU number @@ -581,6 +627,21 @@ int cache_setup_acpi(unsigned int cpu) return status; } +/** + * acpi_pptt_cpu_is_thread() - Determine if CPU is a thread + * @cpu: Kernel logical CPU number + * + * + * Return: 1, a thread + * 0, not a thread + * -ENOENT ,if the PPTT doesn't exist, the CPU cannot be found or + * the table revision isn't new enough. + */ +int acpi_pptt_cpu_is_thread(unsigned int cpu) +{ + return check_acpi_cpu_flag(cpu, 2, ACPI_PPTT_ACPI_PROCESSOR_IS_THREAD); +} + /** * find_acpi_cpu_topology() - Determine a unique topology value for a given CPU * @cpu: Kernel logical CPU number @@ -641,7 +702,6 @@ int find_acpi_cpu_cache_topology(unsigned int cpu, int level) return ret; } - /** * find_acpi_cpu_topology_package() - Determine a unique CPU package value * @cpu: Kernel logical CPU number diff --git a/include/linux/acpi.h b/include/linux/acpi.h index d315d86844e4..3e339375e213 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1301,10 +1301,15 @@ static inline int lpit_read_residency_count_address(u64 *address) #endif #ifdef CONFIG_ACPI_PPTT +int acpi_pptt_cpu_is_thread(unsigned int cpu); int find_acpi_cpu_topology(unsigned int cpu, int level); int find_acpi_cpu_topology_package(unsigned int cpu); int find_acpi_cpu_cache_topology(unsigned int cpu, int level); #else +static inline int acpi_pptt_cpu_is_thread(unsigned int cpu) +{ + return -EINVAL; +} static inline int find_acpi_cpu_topology(unsigned int cpu, int level) { return -EINVAL;