xref: /openbmc/linux/arch/sh/kernel/topology.c (revision cf41d18b)
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);
75