xref: /linux/arch/s390/kernel/processor.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  *  arch/s390/kernel/processor.c
3  *
4  *  Copyright IBM Corp. 2008
5  *  Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
6  */
7 
8 #define KMSG_COMPONENT "cpu"
9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
10 
11 #include <linux/kernel.h>
12 #include <linux/init.h>
13 #include <linux/smp.h>
14 #include <linux/seq_file.h>
15 #include <linux/delay.h>
16 #include <linux/cpu.h>
17 #include <asm/elf.h>
18 #include <asm/lowcore.h>
19 #include <asm/param.h>
20 
21 static DEFINE_PER_CPU(struct cpuid, cpu_id);
22 
23 /*
24  * cpu_init - initializes state that is per-CPU.
25  */
26 void __cpuinit cpu_init(void)
27 {
28 	struct cpuid *id = &per_cpu(cpu_id, smp_processor_id());
29 
30 	get_cpu_id(id);
31 	atomic_inc(&init_mm.mm_count);
32 	current->active_mm = &init_mm;
33 	BUG_ON(current->mm);
34 	enter_lazy_tlb(&init_mm, current);
35 }
36 
37 /*
38  * show_cpuinfo - Get information on one CPU for use by procfs.
39  */
40 static int show_cpuinfo(struct seq_file *m, void *v)
41 {
42 	static const char *hwcap_str[10] = {
43 		"esan3", "zarch", "stfle", "msa", "ldisp", "eimm", "dfp",
44 		"edat", "etf3eh", "highgprs"
45 	};
46 	unsigned long n = (unsigned long) v - 1;
47 	int i;
48 
49 	if (!n) {
50 		s390_adjust_jiffies();
51 		seq_printf(m, "vendor_id       : IBM/S390\n"
52 			   "# processors    : %i\n"
53 			   "bogomips per cpu: %lu.%02lu\n",
54 			   num_online_cpus(), loops_per_jiffy/(500000/HZ),
55 			   (loops_per_jiffy/(5000/HZ))%100);
56 		seq_puts(m, "features\t: ");
57 		for (i = 0; i < 10; i++)
58 			if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
59 				seq_printf(m, "%s ", hwcap_str[i]);
60 		seq_puts(m, "\n");
61 	}
62 	get_online_cpus();
63 	if (cpu_online(n)) {
64 		struct cpuid *id = &per_cpu(cpu_id, n);
65 		seq_printf(m, "processor %li: "
66 			   "version = %02X,  "
67 			   "identification = %06X,  "
68 			   "machine = %04X\n",
69 			   n, id->version, id->ident, id->machine);
70 	}
71 	put_online_cpus();
72 	return 0;
73 }
74 
75 static void *c_start(struct seq_file *m, loff_t *pos)
76 {
77 	return *pos < nr_cpu_ids ? (void *)((unsigned long) *pos + 1) : NULL;
78 }
79 
80 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
81 {
82 	++*pos;
83 	return c_start(m, pos);
84 }
85 
86 static void c_stop(struct seq_file *m, void *v)
87 {
88 }
89 
90 const struct seq_operations cpuinfo_op = {
91 	.start	= c_start,
92 	.next	= c_next,
93 	.stop	= c_stop,
94 	.show	= show_cpuinfo,
95 };
96 
97