From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AG47ELv9qnTEP6ja2DLscqQdOOx5/TCWczj7PBmyNe9/VwYm+iNcseI+CFtoEU8JtZlohDNIM1Zc ARC-Seal: i=1; a=rsa-sha256; t=1519855648; cv=none; d=google.com; s=arc-20160816; b=tFq4f1YjV1UpZok4WcfrZdCjKCbxSq/kRcH+fhqOrrQgGBob7DLjigWwI3y4cJVO3W zbtLOEFD3ZOnUbFxYRjjqJ4wVQWIBTVzR+BLmEHQ7ky8R4N7O1qGzsnDxgvpPd56BXAU Yn9Ozg7ogCdHQ33+eqfO9n5Z0LrBEBDuAqH0fwZ4wWXsJ8rEcKPpMf5mP2AAibnUc7Sp ++5FZibeaxnt3HEPSobdmTte1OKli2cyThpxjHeMe0Ep/Hhy4js5hvvXuM8yZJsQfUgj HetBnAXA8P6IudUgFnr3LslroLV32LX9iI5uksxAZwEgEfjfQOYeaLmu+a4GX1PBM8Tp hrqA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=references:in-reply-to:message-id:date:subject:cc:to:from :arc-authentication-results; bh=QJLztZ2g/MRSiA6xzxg+u6RJFe94U/bV8XHyRQyuNd0=; b=khzmbhAzMtr7SNQ/37kE7HQl4c5cEBrk7FJp+pfjfYlegGB62VJEzusHPPDWVTgxNl TN5SPdX5j9fYIU5/izO0vnY3KQr1u1cXwqrWgtpw8mwZqeSKsth5BdPpFi1Fg1JT3U3J fDpvNeoIpvG3KyrQnHL/ImeGtdzCrrl/9RBgn2iT0cB3I528gX2sPqqc5A3WVsixUGX/ dmzpiqbghLtK6tgp+TgpCMpQ/dp+VU/Fr+DX5bgfydPGXI9cjSyducgzIaDhmDWyynVS XHIdlPvhe5zER733ZFkQlPH+NHC/cJuG/rqf+T08rX/q8MpCXfI0CT1I9rypBeCootd/ Cklw== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: domain of jeremy.linton@arm.com designates 217.140.101.70 as permitted sender) smtp.mailfrom=jeremy.linton@arm.com Authentication-Results: mx.google.com; spf=pass (google.com: domain of jeremy.linton@arm.com designates 217.140.101.70 as permitted sender) smtp.mailfrom=jeremy.linton@arm.com From: Jeremy Linton To: linux-acpi@vger.kernel.org Cc: linux-arm-kernel@lists.infradead.org, sudeep.holla@arm.com, lorenzo.pieralisi@arm.com, hanjun.guo@linaro.org, rjw@rjwysocki.net, will.deacon@arm.com, catalin.marinas@arm.com, gregkh@linuxfoundation.org, mark.rutland@arm.com, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, wangxiongfeng2@huawei.com, vkilari@codeaurora.org, ahs3@redhat.com, dietmar.eggemann@arm.com, morten.rasmussen@arm.com, palmer@sifive.com, lenb@kernel.org, john.garry@huawei.com, austinwc@codeaurora.org, tnowicki@caviumnetworks.com, Jeremy Linton Subject: [PATCH v7 09/13] ACPI/PPTT: Add topology parsing code Date: Wed, 28 Feb 2018 16:06:15 -0600 Message-Id: <20180228220619.6992-10-jeremy.linton@arm.com> X-Mailer: git-send-email 2.13.6 In-Reply-To: <20180228220619.6992-1-jeremy.linton@arm.com> References: <20180228220619.6992-1-jeremy.linton@arm.com> X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-THRID: =?utf-8?q?1593684156400334198?= X-GMAIL-MSGID: =?utf-8?q?1593684156400334198?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 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 | 153 +++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/acpi.h | 4 ++ 2 files changed, 157 insertions(+) diff --git a/drivers/acpi/pptt.c b/drivers/acpi/pptt.c index c98f94ebd272..d66342c2eb29 100644 --- a/drivers/acpi/pptt.c +++ b/drivers/acpi/pptt.c @@ -424,6 +424,79 @@ 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 an 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 ACPI_PTR_DIFF(cpu_node, 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 @@ -487,3 +560,83 @@ 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_cache_topology() - Determine a unique cache topology value + * @cpu: Kernel logical cpu number + * @level: The cache level for which we would like a unique ID + * + * Determine a unique ID for each unified cache in the system + * + * 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_cache_topology(unsigned int cpu, int level) +{ + struct acpi_table_header *table; + struct acpi_pptt_cache *found_cache; + acpi_status status; + u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); + struct acpi_pptt_processor *cpu_node = NULL; + int ret = -1; + + status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); + if (ACPI_FAILURE(status)) { + pr_err_once("No PPTT table found, topology may be inaccurate\n"); + return -ENOENT; + } + + found_cache = acpi_find_cache_node(table, acpi_cpu_id, + CACHE_TYPE_UNIFIED, + level, + &cpu_node); + if (found_cache) + ret = ACPI_PTR_DIFF(cpu_node, table); + + acpi_put_table(table); + + return ret; +} + + +/** + * 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); +} diff --git a/include/linux/acpi.h b/include/linux/acpi.h index 968173ec2726..2c9b6a000ea7 100644 --- a/include/linux/acpi.h +++ b/include/linux/acpi.h @@ -1290,4 +1290,8 @@ static inline int lpit_read_residency_count_address(u64 *address) } #endif +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); + #endif /*_LINUX_ACPI_H*/ -- 2.13.6