xref: /openbmc/linux/arch/s390/kernel/processor.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
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 
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  * print_cpu_info - print basic information about a cpu
39  */
40 void __cpuinit print_cpu_info(void)
41 {
42 	struct cpuid *id = &per_cpu(cpu_id, smp_processor_id());
43 
44 	pr_info("Processor %d started, address %d, identification %06X\n",
45 		S390_lowcore.cpu_nr, stap(), id->ident);
46 }
47 
48 /*
49  * show_cpuinfo - Get information on one CPU for use by procfs.
50  */
51 static int show_cpuinfo(struct seq_file *m, void *v)
52 {
53 	static const char *hwcap_str[10] = {
54 		"esan3", "zarch", "stfle", "msa", "ldisp", "eimm", "dfp",
55 		"edat", "etf3eh", "highgprs"
56 	};
57 	unsigned long n = (unsigned long) v - 1;
58 	int i;
59 
60 	s390_adjust_jiffies();
61 	preempt_disable();
62 	if (!n) {
63 		seq_printf(m, "vendor_id       : IBM/S390\n"
64 			   "# processors    : %i\n"
65 			   "bogomips per cpu: %lu.%02lu\n",
66 			   num_online_cpus(), loops_per_jiffy/(500000/HZ),
67 			   (loops_per_jiffy/(5000/HZ))%100);
68 		seq_puts(m, "features\t: ");
69 		for (i = 0; i < 10; i++)
70 			if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
71 				seq_printf(m, "%s ", hwcap_str[i]);
72 		seq_puts(m, "\n");
73 	}
74 
75 	if (cpu_online(n)) {
76 		struct cpuid *id = &per_cpu(cpu_id, n);
77 		seq_printf(m, "processor %li: "
78 			   "version = %02X,  "
79 			   "identification = %06X,  "
80 			   "machine = %04X\n",
81 			   n, id->version, id->ident, id->machine);
82 	}
83 	preempt_enable();
84 	return 0;
85 }
86 
87 static void *c_start(struct seq_file *m, loff_t *pos)
88 {
89 	return *pos < NR_CPUS ? (void *)((unsigned long) *pos + 1) : NULL;
90 }
91 
92 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
93 {
94 	++*pos;
95 	return c_start(m, pos);
96 }
97 
98 static void c_stop(struct seq_file *m, void *v)
99 {
100 }
101 
102 const struct seq_operations cpuinfo_op = {
103 	.start	= c_start,
104 	.next	= c_next,
105 	.stop	= c_stop,
106 	.show	= show_cpuinfo,
107 };
108 
109