summaryrefslogtreecommitdiff
path: root/arch/s390/kernel/processor.c
blob: ab236bd970bb332d9237c232909e39c5610d548f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
/*
 *  Copyright IBM Corp. 2008
 *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
 */

#define KMSG_COMPONENT "cpu"
#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/seq_file.h>
#include <linux/delay.h>
#include <linux/cpu.h>
#include <asm/diag.h>
#include <asm/elf.h>
#include <asm/facility.h>
#include <asm/lowcore.h>
#include <asm/param.h>
#include <asm/smp.h>

static DEFINE_PER_CPU(struct cpuid, cpu_id);

void notrace cpu_relax(void)
{
	if (!smp_cpu_mtid && MACHINE_HAS_DIAG44) {
		diag_stat_inc(DIAG_STAT_X044);
		asm volatile("diag 0,0,0x44");
	}
	barrier();
}
EXPORT_SYMBOL(cpu_relax);

/*
 * cpu_init - initializes state that is per-CPU.
 */
void cpu_init(void)
{
	struct cpuid *id = this_cpu_ptr(&cpu_id);

	get_cpu_id(id);
	atomic_inc(&init_mm.mm_count);
	current->active_mm = &init_mm;
	BUG_ON(current->mm);
	enter_lazy_tlb(&init_mm, current);
}

/*
 * cpu_have_feature - Test CPU features on module initialization
 */
int cpu_have_feature(unsigned int num)
{
	return elf_hwcap & (1UL << num);
}
EXPORT_SYMBOL(cpu_have_feature);

/*
 * show_cpuinfo - Get information on one CPU for use by procfs.
 */
static int show_cpuinfo(struct seq_file *m, void *v)
{
	static const char *hwcap_str[] = {
		"esan3", "zarch", "stfle", "msa", "ldisp", "eimm", "dfp",
		"edat", "etf3eh", "highgprs", "te", "vx"
	};
	unsigned long n = (unsigned long) v - 1;
	int i;

	if (!n) {
		s390_adjust_jiffies();
		seq_printf(m, "vendor_id       : IBM/S390\n"
			   "# processors    : %i\n"
			   "bogomips per cpu: %lu.%02lu\n",
			   num_online_cpus(), loops_per_jiffy/(500000/HZ),
			   (loops_per_jiffy/(5000/HZ))%100);
		seq_puts(m, "features\t: ");
		for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
			if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
				seq_printf(m, "%s ", hwcap_str[i]);
		seq_puts(m, "\n");
		show_cacheinfo(m);
	}
	get_online_cpus();
	if (cpu_online(n)) {
		struct cpuid *id = &per_cpu(cpu_id, n);
		seq_printf(m, "processor %li: "
			   "version = %02X,  "
			   "identification = %06X,  "
			   "machine = %04X\n",
			   n, id->version, id->ident, id->machine);
	}
	put_online_cpus();
	return 0;
}

static void *c_start(struct seq_file *m, loff_t *pos)
{
	return *pos < nr_cpu_ids ? (void *)((unsigned long) *pos + 1) : NULL;
}

static void *c_next(struct seq_file *m, void *v, loff_t *pos)
{
	++*pos;
	return c_start(m, pos);
}

static void c_stop(struct seq_file *m, void *v)
{
}

const struct seq_operations cpuinfo_op = {
	.start	= c_start,
	.next	= c_next,
	.stop	= c_stop,
	.show	= show_cpuinfo,
};

int s390_isolate_bp(void)
{
	if (!test_facility(82))
		return -EOPNOTSUPP;
	set_thread_flag(TIF_ISOLATE_BP);
	return 0;
}
EXPORT_SYMBOL(s390_isolate_bp);

int s390_isolate_bp_guest(void)
{
	if (!test_facility(82))
		return -EOPNOTSUPP;
	set_thread_flag(TIF_ISOLATE_BP_GUEST);
	return 0;
}
EXPORT_SYMBOL(s390_isolate_bp_guest);