1/*
 2 * arch/parisc/kernel/topology.c - Populate sysfs with topology information
 3 *
 4 * This program is free software; you can redistribute it and/or modify
 5 * it under the terms of the GNU General Public License as published by
 6 * the Free Software Foundation; either version 2 of the License, or
 7 * (at your option) any later version.
 8 *
 9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
12 * NON INFRINGEMENT.  See the GNU General Public License for more
13 * details.
14 *
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
18 */
19
20#include <linux/init.h>
21#include <linux/smp.h>
 
22#include <linux/cpu.h>
23#include <linux/cache.h>
 
 
24
25static DEFINE_PER_CPU(struct cpu, cpu_devices);
26
27static int __init topology_init(void)
 
 
 
 
 
28{
29	int num;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
30
31	for_each_present_cpu(num) {
32		register_cpu(&per_cpu(cpu_devices, num), num);
 
 
 
 
 
 
 
 
 
33	}
34	return 0;
 
 
 
 
 
 
 
 
 
35}
36
37subsys_initcall(topology_init);
 
 
 
 
 
 
 

 1/*
 2 * arch/parisc/kernel/topology.c
 3 *
 4 * Copyright (C) 2017 Helge Deller <deller@gmx.de>
 
 
 
 5 *
 6 * based on arch/arm/kernel/topology.c
 
 
 
 
 7 *
 8 * This file is subject to the terms and conditions of the GNU General Public
 9 * License.  See the file "COPYING" in the main directory of this archive
10 * for more details.
11 */
12
13#include <linux/percpu.h>
14#include <linux/sched.h>
15#include <linux/sched/topology.h>
16#include <linux/cpu.h>
17
18#include <asm/topology.h>
19#include <asm/sections.h>
20
21static DEFINE_PER_CPU(struct cpu, cpu_devices);
22
23/*
24 * store_cpu_topology is called at boot when only one cpu is running
25 * and with the mutex cpu_hotplug.lock locked, when several cpus have booted,
26 * which prevents simultaneous write access to cpu_topology array
27 */
28void store_cpu_topology(unsigned int cpuid)
29{
30	struct cpu_topology *cpuid_topo = &cpu_topology[cpuid];
31	struct cpuinfo_parisc *p;
32	int max_socket = -1;
33	unsigned long cpu;
34
35	/* If the cpu topology has been already set, just return */
36	if (cpuid_topo->core_id != -1)
37		return;
38
39#ifdef CONFIG_HOTPLUG_CPU
40	per_cpu(cpu_devices, cpuid).hotpluggable = 1;
41#endif
42	if (register_cpu(&per_cpu(cpu_devices, cpuid), cpuid))
43		pr_warn("Failed to register CPU%d device", cpuid);
44
45	/* create cpu topology mapping */
46	cpuid_topo->thread_id = -1;
47	cpuid_topo->core_id = 0;
48
49	p = &per_cpu(cpu_data, cpuid);
50	for_each_online_cpu(cpu) {
51		const struct cpuinfo_parisc *cpuinfo = &per_cpu(cpu_data, cpu);
52
53		if (cpu == cpuid) /* ignore current cpu */
54			continue;
55
56		if (cpuinfo->cpu_loc == p->cpu_loc) {
57			cpuid_topo->core_id = cpu_topology[cpu].core_id;
58			if (p->cpu_loc) {
59				cpuid_topo->core_id++;
60				cpuid_topo->package_id = cpu_topology[cpu].package_id;
61				continue;
62			}
63		}
64
65		if (cpuid_topo->package_id == -1)
66			max_socket = max(max_socket, cpu_topology[cpu].package_id);
67	}
68
69	if (cpuid_topo->package_id == -1)
70		cpuid_topo->package_id = max_socket + 1;
71
72	update_siblings_masks(cpuid);
73
74	pr_info("CPU%u: cpu core %d of socket %d\n",
75		cpuid,
76		cpu_topology[cpuid].core_id,
77		cpu_topology[cpuid].package_id);
78}
79
80/*
81 * init_cpu_topology is called at boot when only one cpu is running
82 * which prevent simultaneous write access to cpu_topology array
83 */
84void __init init_cpu_topology(void)
85{
86	reset_cpu_topology();
87}