xref: /openbmc/linux/arch/sh/kernel/topology.c (revision f3539c12)
1 /*
2  * arch/sh/kernel/topology.c
3  *
4  *  Copyright (C) 2007  Paul Mundt
5  *
6  * This file is subject to the terms and conditions of the GNU General Public
7  * License.  See the file "COPYING" in the main directory of this archive
8  * for more details.
9  */
10 #include <linux/cpu.h>
11 #include <linux/cpumask.h>
12 #include <linux/init.h>
13 #include <linux/percpu.h>
14 #include <linux/topology.h>
15 #include <linux/node.h>
16 #include <linux/nodemask.h>
17 #include <linux/export.h>
18 
19 static DEFINE_PER_CPU(struct cpu, cpu_devices);
20 
21 cpumask_t cpu_core_map[NR_CPUS];
22 EXPORT_SYMBOL(cpu_core_map);
23 
24 static cpumask_t cpu_coregroup_map(int cpu)
25 {
26 	/*
27 	 * Presently all SH-X3 SMP cores are multi-cores, so just keep it
28 	 * simple until we have a method for determining topology..
29 	 */
30 	return *cpu_possible_mask;
31 }
32 
33 const struct cpumask *cpu_coregroup_mask(int cpu)
34 {
35 	return &cpu_core_map[cpu];
36 }
37 
38 int arch_update_cpu_topology(void)
39 {
40 	unsigned int cpu;
41 
42 	for_each_possible_cpu(cpu)
43 		cpu_core_map[cpu] = cpu_coregroup_map(cpu);
44 
45 	return 0;
46 }
47 
48 static int __init topology_init(void)
49 {
50 	int i, ret;
51 
52 #ifdef CONFIG_NEED_MULTIPLE_NODES
53 	for_each_online_node(i)
54 		register_one_node(i);
55 #endif
56 
57 	for_each_present_cpu(i) {
58 		struct cpu *c = &per_cpu(cpu_devices, i);
59 
60 		c->hotpluggable = 1;
61 
62 		ret = register_cpu(c, i);
63 		if (unlikely(ret))
64 			printk(KERN_WARNING "%s: register_cpu %d failed (%d)\n",
65 			       __func__, i, ret);
66 	}
67 
68 #if defined(CONFIG_NUMA) && !defined(CONFIG_SMP)
69 	/*
70 	 * In the UP case, make sure the CPU association is still
71 	 * registered under each node. Without this, sysfs fails
72 	 * to make the connection between nodes other than node0
73 	 * and cpu0.
74 	 */
75 	for_each_online_node(i)
76 		if (i != numa_node_id())
77 			register_cpu_under_node(raw_smp_processor_id(), i);
78 #endif
79 
80 	return 0;
81 }
82 subsys_initcall(topology_init);
83