arch/sh/kernel/topology.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * arch/sh/kernel/topology.c
   4  *
   5  *  Copyright (C) 2007  Paul Mundt
   6  */
   7 #include <linux/cpu.h>
   8 #include <linux/cpumask.h>
   9 #include <linux/init.h>
  10 #include <linux/percpu.h>
  11 #include <linux/topology.h>
  12 #include <linux/node.h>
  13 #include <linux/nodemask.h>
  14 #include <linux/export.h>
  15
  16 static DEFINE_PER_CPU(struct cpu, cpu_devices);
  17
  18 cpumask_t cpu_core_map[NR_CPUS];
  19 EXPORT_SYMBOL(cpu_core_map);
  20
  21 static cpumask_t cpu_coregroup_map(int cpu)
  22 {
  23         /*
  24          * Presently all SH-X3 SMP cores are multi-cores, so just keep it
  25          * simple until we have a method for determining topology..
  26          */
  27         return *cpu_possible_mask;
  28 }
  29
  30 const struct cpumask *cpu_coregroup_mask(int cpu)
  31 {
  32         return &cpu_core_map[cpu];
  33 }
  34
  35 int arch_update_cpu_topology(void)
  36 {
  37         unsigned int cpu;
  38
  39         for_each_possible_cpu(cpu)
  40                 cpu_core_map[cpu] = cpu_coregroup_map(cpu);
  41
  42         return 0;
  43 }
  44
  45 static int __init topology_init(void)
  46 {
  47         int i, ret;
  48
  49 #ifdef CONFIG_NEED_MULTIPLE_NODES
  50         for_each_online_node(i)
  51                 register_one_node(i);
  52 #endif
  53
  54         for_each_present_cpu(i) {
  55                 struct cpu *c = &per_cpu(cpu_devices, i);
  56
  57                 c->hotpluggable = 1;
  58
  59                 ret = register_cpu(c, i);
  60                 if (unlikely(ret))
  61                         printk(KERN_WARNING "%s: register_cpu %d failed (%d)\n",
  62                                __func__, i, ret);
  63         }
  64
  65 #if defined(CONFIG_NUMA) && !defined(CONFIG_SMP)
  66         /*
  67          * In the UP case, make sure the CPU association is still
  68          * registered under each node. Without this, sysfs fails
  69          * to make the connection between nodes other than node0
  70          * and cpu0.
  71          */
  72         for_each_online_node(i)
  73                 if (i != numa_node_id())
  74                         register_cpu_under_node(raw_smp_processor_id(), i);
  75 #endif
  76
  77         return 0;
  78 }
  79 subsys_initcall(topology_init);