summaryrefslogtreecommitdiffstats
path: root/arch/s390/kernel/processor.c
blob: 675d4be0c2b77f18e53865bc57c05d9244fc3137 (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
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
// SPDX-License-Identifier: GPL-2.0
/*
 *  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/cpufeature.h>
#include <linux/bitops.h>
#include <linux/kernel.h>
#include <linux/sched/mm.h>
#include <linux/init.h>
#include <linux/seq_file.h>
#include <linux/mm_types.h>
#include <linux/delay.h>
#include <linux/cpu.h>

#include <asm/diag.h>
#include <asm/facility.h>
#include <asm/elf.h>
#include <asm/lowcore.h>
#include <asm/param.h>
#include <asm/smp.h>

struct cpu_info {
	unsigned int cpu_mhz_dynamic;
	unsigned int cpu_mhz_static;
	struct cpuid cpu_id;
};

static DEFINE_PER_CPU(struct cpu_info, cpu_info);

static bool machine_has_cpu_mhz;

void __init cpu_detect_mhz_feature(void)
{
	if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL)
		machine_has_cpu_mhz = true;
}

static void update_cpu_mhz(void *arg)
{
	unsigned long mhz;
	struct cpu_info *c;

	mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0);
	c = this_cpu_ptr(&cpu_info);
	c->cpu_mhz_dynamic = mhz >> 32;
	c->cpu_mhz_static = mhz & 0xffffffff;
}

void s390_update_cpu_mhz(void)
{
	s390_adjust_jiffies();
	if (machine_has_cpu_mhz)
		on_each_cpu(update_cpu_mhz, NULL, 0);
}

void notrace cpu_relax_yield(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_yield);

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

	get_cpu_id(id);
	if (machine_has_cpu_mhz)
		update_cpu_mhz(NULL);
	mmgrab(&init_mm);
	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);

static void show_facilities(struct seq_file *m)
{
	unsigned int bit;
	long *facilities;

	facilities = (long *)&S390_lowcore.stfle_fac_list;
	seq_puts(m, "facilities      :");
	for_each_set_bit_inv(bit, facilities, MAX_FACILITY_BIT)
		seq_printf(m, " %d", bit);
	seq_putc(m, '\n');
}

static void show_cpu_summary(struct seq_file *m, void *v)
{
	static const char *hwcap_str[] = {
		"esan3", "zarch", "stfle", "msa", "ldisp", "eimm", "dfp",
		"edat", "etf3eh", "highgprs", "te", "vx", "vxd", "vxe", "gs"
	};
	static const char * const int_hwcap_str[] = {
		"sie"
	};
	int i, cpu;

	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_printf(m, "max thread id   : %d\n", smp_cpu_mtid);
	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]);
	for (i = 0; i < ARRAY_SIZE(int_hwcap_str); i++)
		if (int_hwcap_str[i] && (int_hwcap & (1UL << i)))
			seq_printf(m, "%s ", int_hwcap_str[i]);
	seq_puts(m, "\n");
	show_facilities(m);
	show_cacheinfo(m);
	for_each_online_cpu(cpu) {
		struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu);

		seq_printf(m, "processor %d: "
			   "version = %02X,  "
			   "identification = %06X,  "
			   "machine = %04X\n",
			   cpu, id->version, id->ident, id->machine);
	}
}

static void show_cpu_mhz(struct seq_file *m, unsigned long n)
{
	struct cpu_info *c = per_cpu_ptr(&cpu_info, n);

	seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic);
	seq_printf(m, "cpu MHz static  : %d\n", c->cpu_mhz_static);
}

/*
 * show_cpuinfo - Get information on one CPU for use by procfs.
 */
static int show_cpuinfo(struct seq_file *m, void *v)
{
	unsigned long n = (unsigned long) v - 1;
	unsigned long first = cpumask_first(cpu_online_mask);

	if (n == first)
		show_cpu_summary(m, v);
	if (!machine_has_cpu_mhz)
		return 0;
	seq_printf(m, "\ncpu number      : %ld\n", n);
	show_cpu_mhz(m, n);
	return 0;
}

static inline void *c_update(loff_t *pos)
{
	if (*pos)
		*pos = cpumask_next(*pos - 1, cpu_online_mask);
	else
		*pos = cpumask_first(cpu_online_mask);
	return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
}

static void *c_start(struct seq_file *m, loff_t *pos)
{
	get_online_cpus();
	return c_update(pos);
}

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

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

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);