2 * Copyright IBM Corp. 2008
3 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
6 #define KMSG_COMPONENT "cpu"
7 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9 #include <linux/cpufeature.h>
10 #include <linux/kernel.h>
11 #include <linux/sched/mm.h>
12 #include <linux/init.h>
13 #include <linux/seq_file.h>
14 #include <linux/mm_types.h>
15 #include <linux/delay.h>
16 #include <linux/cpu.h>
19 #include <asm/facility.h>
21 #include <asm/lowcore.h>
22 #include <asm/param.h>
26 unsigned int cpu_mhz_dynamic;
27 unsigned int cpu_mhz_static;
31 static DEFINE_PER_CPU(struct cpu_info, cpu_info);
33 static bool machine_has_cpu_mhz;
35 void __init cpu_detect_mhz_feature(void)
37 if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL)
38 machine_has_cpu_mhz = true;
41 static void update_cpu_mhz(void *arg)
46 mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0);
47 c = this_cpu_ptr(&cpu_info);
48 c->cpu_mhz_dynamic = mhz >> 32;
49 c->cpu_mhz_static = mhz & 0xffffffff;
52 void s390_update_cpu_mhz(void)
54 s390_adjust_jiffies();
55 if (machine_has_cpu_mhz)
56 on_each_cpu(update_cpu_mhz, NULL, 0);
59 void notrace cpu_relax_yield(void)
61 if (!smp_cpu_mtid && MACHINE_HAS_DIAG44) {
62 diag_stat_inc(DIAG_STAT_X044);
63 asm volatile("diag 0,0,0x44");
67 EXPORT_SYMBOL(cpu_relax_yield);
70 * cpu_init - initializes state that is per-CPU.
74 struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id);
77 if (machine_has_cpu_mhz)
80 current->active_mm = &init_mm;
82 enter_lazy_tlb(&init_mm, current);
86 * cpu_have_feature - Test CPU features on module initialization
88 int cpu_have_feature(unsigned int num)
90 return elf_hwcap & (1UL << num);
92 EXPORT_SYMBOL(cpu_have_feature);
94 static void show_cpu_summary(struct seq_file *m, void *v)
96 static const char *hwcap_str[] = {
97 "esan3", "zarch", "stfle", "msa", "ldisp", "eimm", "dfp",
98 "edat", "etf3eh", "highgprs", "te", "vx", "vxd", "vxe"
100 static const char * const int_hwcap_str[] = {
105 seq_printf(m, "vendor_id : IBM/S390\n"
106 "# processors : %i\n"
107 "bogomips per cpu: %lu.%02lu\n",
108 num_online_cpus(), loops_per_jiffy/(500000/HZ),
109 (loops_per_jiffy/(5000/HZ))%100);
110 seq_printf(m, "max thread id : %d\n", smp_cpu_mtid);
111 seq_puts(m, "features\t: ");
112 for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
113 if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
114 seq_printf(m, "%s ", hwcap_str[i]);
115 for (i = 0; i < ARRAY_SIZE(int_hwcap_str); i++)
116 if (int_hwcap_str[i] && (int_hwcap & (1UL << i)))
117 seq_printf(m, "%s ", int_hwcap_str[i]);
120 for_each_online_cpu(cpu) {
121 struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu);
123 seq_printf(m, "processor %d: "
125 "identification = %06X, "
127 cpu, id->version, id->ident, id->machine);
131 static void show_cpu_mhz(struct seq_file *m, unsigned long n)
133 struct cpu_info *c = per_cpu_ptr(&cpu_info, n);
135 seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic);
136 seq_printf(m, "cpu MHz static : %d\n", c->cpu_mhz_static);
140 * show_cpuinfo - Get information on one CPU for use by procfs.
142 static int show_cpuinfo(struct seq_file *m, void *v)
144 unsigned long n = (unsigned long) v - 1;
147 show_cpu_summary(m, v);
148 if (!machine_has_cpu_mhz)
150 seq_printf(m, "\ncpu number : %ld\n", n);
155 static inline void *c_update(loff_t *pos)
158 *pos = cpumask_next(*pos - 1, cpu_online_mask);
159 return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
162 static void *c_start(struct seq_file *m, loff_t *pos)
165 return c_update(pos);
168 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
171 return c_update(pos);
174 static void c_stop(struct seq_file *m, void *v)
179 const struct seq_operations cpuinfo_op = {
183 .show = show_cpuinfo,