1/*
2 *  Copyright IBM Corp. 2008
3 *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
4 */
5
6#define KMSG_COMPONENT "cpu"
7#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
8
9#include <linux/kernel.h>
10#include <linux/init.h>
11#include <linux/seq_file.h>
12#include <linux/delay.h>
13#include <linux/cpu.h>
14#include <asm/diag.h>
15#include <asm/elf.h>
16#include <asm/lowcore.h>
17#include <asm/param.h>
18#include <asm/smp.h>
19
20static DEFINE_PER_CPU(struct cpuid, cpu_id);
21
22void notrace cpu_relax(void)
23{
24	if (!smp_cpu_mtid && MACHINE_HAS_DIAG44) {
25		diag_stat_inc(DIAG_STAT_X044);
26		asm volatile("diag 0,0,0x44");
27	}
28	barrier();
29}
30EXPORT_SYMBOL(cpu_relax);
31
32/*
33 * cpu_init - initializes state that is per-CPU.
34 */
35void cpu_init(void)
36{
37	struct cpuid *id = this_cpu_ptr(&cpu_id);
38
39	get_cpu_id(id);
40	atomic_inc(&init_mm.mm_count);
41	current->active_mm = &init_mm;
42	BUG_ON(current->mm);
43	enter_lazy_tlb(&init_mm, current);
44}
45
46/*
47 * cpu_have_feature - Test CPU features on module initialization
48 */
49int cpu_have_feature(unsigned int num)
50{
51	return elf_hwcap & (1UL << num);
52}
53EXPORT_SYMBOL(cpu_have_feature);
54
55/*
56 * show_cpuinfo - Get information on one CPU for use by procfs.
57 */
58static int show_cpuinfo(struct seq_file *m, void *v)
59{
60	static const char *hwcap_str[] = {
61		"esan3", "zarch", "stfle", "msa", "ldisp", "eimm", "dfp",
62		"edat", "etf3eh", "highgprs", "te", "vx"
63	};
64	unsigned long n = (unsigned long) v - 1;
65	int i;
66
67	if (!n) {
68		s390_adjust_jiffies();
69		seq_printf(m, "vendor_id       : IBM/S390\n"
70			   "# processors    : %i\n"
71			   "bogomips per cpu: %lu.%02lu\n",
72			   num_online_cpus(), loops_per_jiffy/(500000/HZ),
73			   (loops_per_jiffy/(5000/HZ))%100);
74		seq_puts(m, "features\t: ");
75		for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
76			if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
77				seq_printf(m, "%s ", hwcap_str[i]);
78		seq_puts(m, "\n");
79		show_cacheinfo(m);
80	}
81	get_online_cpus();
82	if (cpu_online(n)) {
83		struct cpuid *id = &per_cpu(cpu_id, n);
84		seq_printf(m, "processor %li: "
85			   "version = %02X,  "
86			   "identification = %06X,  "
87			   "machine = %04X\n",
88			   n, id->version, id->ident, id->machine);
89	}
90	put_online_cpus();
91	return 0;
92}
93
94static void *c_start(struct seq_file *m, loff_t *pos)
95{
96	return *pos < nr_cpu_ids ? (void *)((unsigned long) *pos + 1) : NULL;
97}
98
99static void *c_next(struct seq_file *m, void *v, loff_t *pos)
100{
101	++*pos;
102	return c_start(m, pos);
103}
104
105static void c_stop(struct seq_file *m, void *v)
106{
107}
108
109const struct seq_operations cpuinfo_op = {
110	.start	= c_start,
111	.next	= c_next,
112	.stop	= c_stop,
113	.show	= show_cpuinfo,
114};
115
116