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         for_each_present_cpu(i) {
  50                 struct cpu *c = &per_cpu(cpu_devices, i);
  51
  52                 c->hotpluggable = 1;
  53
  54                 ret = register_cpu(c, i);
  55                 if (unlikely(ret))
  56                         printk(KERN_WARNING "%s: register_cpu %d failed (%d)\n",
  57                                __func__, i, ret);
  58         }
  59
  60 #if defined(CONFIG_NUMA) && !defined(CONFIG_SMP)
  61         /*
  62          * In the UP case, make sure the CPU association is still
  63          * registered under each node. Without this, sysfs fails
  64          * to make the connection between nodes other than node0
  65          * and cpu0.
  66          */
  67         for_each_online_node(i)
  68                 if (i != numa_node_id())
  69                         register_cpu_under_node(raw_smp_processor_id(), i);
  70 #endif
  71
  72         return 0;
  73 }
  74 subsys_initcall(topology_init);