![Suzuki K Poulose](/assets/img/avatar_default.png)
Make use of the new generic helper to convert an of_node of a CPU to the logical CPU id in parsing the topology. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Will Deacon <will.deacon@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
310 lines
6.7 KiB
C
310 lines
6.7 KiB
C
/*
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* arch/arm64/kernel/topology.c
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*
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* Copyright (C) 2011,2013,2014 Linaro Limited.
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*
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* Based on the arm32 version written by Vincent Guittot in turn based on
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* arch/sh/kernel/topology.c
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*/
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#include <linux/arch_topology.h>
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#include <linux/cpu.h>
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#include <linux/cpumask.h>
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#include <linux/init.h>
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#include <linux/percpu.h>
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#include <linux/node.h>
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#include <linux/nodemask.h>
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#include <linux/of.h>
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#include <linux/sched.h>
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#include <linux/sched/topology.h>
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#include <linux/slab.h>
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#include <linux/string.h>
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#include <asm/cpu.h>
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#include <asm/cputype.h>
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#include <asm/topology.h>
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static int __init get_cpu_for_node(struct device_node *node)
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{
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struct device_node *cpu_node;
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int cpu;
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cpu_node = of_parse_phandle(node, "cpu", 0);
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if (!cpu_node)
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return -1;
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cpu = of_cpu_node_to_id(cpu_node);
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if (cpu >= 0)
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topology_parse_cpu_capacity(cpu_node, cpu);
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else
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pr_crit("Unable to find CPU node for %pOF\n", cpu_node);
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of_node_put(cpu_node);
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return cpu;
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}
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static int __init parse_core(struct device_node *core, int cluster_id,
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int core_id)
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{
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char name[10];
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bool leaf = true;
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int i = 0;
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int cpu;
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struct device_node *t;
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do {
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snprintf(name, sizeof(name), "thread%d", i);
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t = of_get_child_by_name(core, name);
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if (t) {
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leaf = false;
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cpu = get_cpu_for_node(t);
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if (cpu >= 0) {
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cpu_topology[cpu].cluster_id = cluster_id;
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cpu_topology[cpu].core_id = core_id;
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cpu_topology[cpu].thread_id = i;
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} else {
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pr_err("%pOF: Can't get CPU for thread\n",
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t);
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of_node_put(t);
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return -EINVAL;
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}
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of_node_put(t);
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}
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i++;
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} while (t);
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cpu = get_cpu_for_node(core);
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if (cpu >= 0) {
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if (!leaf) {
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pr_err("%pOF: Core has both threads and CPU\n",
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core);
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return -EINVAL;
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}
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cpu_topology[cpu].cluster_id = cluster_id;
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cpu_topology[cpu].core_id = core_id;
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} else if (leaf) {
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pr_err("%pOF: Can't get CPU for leaf core\n", core);
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return -EINVAL;
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}
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return 0;
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}
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static int __init parse_cluster(struct device_node *cluster, int depth)
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{
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char name[10];
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bool leaf = true;
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bool has_cores = false;
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struct device_node *c;
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static int cluster_id __initdata;
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int core_id = 0;
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int i, ret;
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/*
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* First check for child clusters; we currently ignore any
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* information about the nesting of clusters and present the
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* scheduler with a flat list of them.
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*/
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i = 0;
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do {
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snprintf(name, sizeof(name), "cluster%d", i);
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c = of_get_child_by_name(cluster, name);
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if (c) {
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leaf = false;
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ret = parse_cluster(c, depth + 1);
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of_node_put(c);
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if (ret != 0)
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return ret;
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}
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i++;
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} while (c);
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/* Now check for cores */
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i = 0;
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do {
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snprintf(name, sizeof(name), "core%d", i);
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c = of_get_child_by_name(cluster, name);
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if (c) {
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has_cores = true;
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if (depth == 0) {
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pr_err("%pOF: cpu-map children should be clusters\n",
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c);
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of_node_put(c);
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return -EINVAL;
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}
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if (leaf) {
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ret = parse_core(c, cluster_id, core_id++);
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} else {
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pr_err("%pOF: Non-leaf cluster with core %s\n",
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cluster, name);
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ret = -EINVAL;
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}
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of_node_put(c);
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if (ret != 0)
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return ret;
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}
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i++;
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} while (c);
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if (leaf && !has_cores)
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pr_warn("%pOF: empty cluster\n", cluster);
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if (leaf)
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cluster_id++;
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return 0;
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}
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static int __init parse_dt_topology(void)
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{
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struct device_node *cn, *map;
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int ret = 0;
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int cpu;
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cn = of_find_node_by_path("/cpus");
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if (!cn) {
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pr_err("No CPU information found in DT\n");
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return 0;
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}
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/*
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* When topology is provided cpu-map is essentially a root
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* cluster with restricted subnodes.
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*/
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map = of_get_child_by_name(cn, "cpu-map");
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if (!map)
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goto out;
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ret = parse_cluster(map, 0);
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if (ret != 0)
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goto out_map;
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topology_normalize_cpu_scale();
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/*
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* Check that all cores are in the topology; the SMP code will
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* only mark cores described in the DT as possible.
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*/
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for_each_possible_cpu(cpu)
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if (cpu_topology[cpu].cluster_id == -1)
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ret = -EINVAL;
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out_map:
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of_node_put(map);
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out:
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of_node_put(cn);
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return ret;
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}
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/*
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* cpu topology table
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*/
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struct cpu_topology cpu_topology[NR_CPUS];
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EXPORT_SYMBOL_GPL(cpu_topology);
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const struct cpumask *cpu_coregroup_mask(int cpu)
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{
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return &cpu_topology[cpu].core_sibling;
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}
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static void update_siblings_masks(unsigned int cpuid)
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{
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struct cpu_topology *cpu_topo, *cpuid_topo = &cpu_topology[cpuid];
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int cpu;
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/* update core and thread sibling masks */
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for_each_possible_cpu(cpu) {
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cpu_topo = &cpu_topology[cpu];
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if (cpuid_topo->cluster_id != cpu_topo->cluster_id)
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continue;
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cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
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if (cpu != cpuid)
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cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
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if (cpuid_topo->core_id != cpu_topo->core_id)
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continue;
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cpumask_set_cpu(cpuid, &cpu_topo->thread_sibling);
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if (cpu != cpuid)
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cpumask_set_cpu(cpu, &cpuid_topo->thread_sibling);
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}
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}
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void store_cpu_topology(unsigned int cpuid)
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{
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struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
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u64 mpidr;
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if (cpuid_topo->cluster_id != -1)
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goto topology_populated;
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mpidr = read_cpuid_mpidr();
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/* Uniprocessor systems can rely on default topology values */
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if (mpidr & MPIDR_UP_BITMASK)
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return;
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/* Create cpu topology mapping based on MPIDR. */
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if (mpidr & MPIDR_MT_BITMASK) {
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/* Multiprocessor system : Multi-threads per core */
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cpuid_topo->thread_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
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cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 1);
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cpuid_topo->cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 2) |
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MPIDR_AFFINITY_LEVEL(mpidr, 3) << 8;
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} else {
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/* Multiprocessor system : Single-thread per core */
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cpuid_topo->thread_id = -1;
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cpuid_topo->core_id = MPIDR_AFFINITY_LEVEL(mpidr, 0);
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cpuid_topo->cluster_id = MPIDR_AFFINITY_LEVEL(mpidr, 1) |
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MPIDR_AFFINITY_LEVEL(mpidr, 2) << 8 |
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MPIDR_AFFINITY_LEVEL(mpidr, 3) << 16;
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}
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pr_debug("CPU%u: cluster %d core %d thread %d mpidr %#016llx\n",
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cpuid, cpuid_topo->cluster_id, cpuid_topo->core_id,
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cpuid_topo->thread_id, mpidr);
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topology_populated:
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update_siblings_masks(cpuid);
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}
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static void __init reset_cpu_topology(void)
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{
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unsigned int cpu;
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for_each_possible_cpu(cpu) {
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struct cpu_topology *cpu_topo = &cpu_topology[cpu];
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cpu_topo->thread_id = -1;
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cpu_topo->core_id = 0;
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cpu_topo->cluster_id = -1;
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cpumask_clear(&cpu_topo->core_sibling);
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cpumask_set_cpu(cpu, &cpu_topo->core_sibling);
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cpumask_clear(&cpu_topo->thread_sibling);
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cpumask_set_cpu(cpu, &cpu_topo->thread_sibling);
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}
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}
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void __init init_cpu_topology(void)
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{
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reset_cpu_topology();
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/*
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* Discard anything that was parsed if we hit an error so we
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* don't use partial information.
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*/
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if (of_have_populated_dt() && parse_dt_topology())
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reset_cpu_topology();
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}
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