1 /* 2 * Copyright IBM Corp. 2008 3 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) 4 */ 5 6 #define KMSG_COMPONENT "cpu" 7 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 8 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> 17 18 #include <asm/diag.h> 19 #include <asm/facility.h> 20 #include <asm/elf.h> 21 #include <asm/lowcore.h> 22 #include <asm/param.h> 23 #include <asm/smp.h> 24 25 struct cpu_info { 26 unsigned int cpu_mhz_dynamic; 27 unsigned int cpu_mhz_static; 28 struct cpuid cpu_id; 29 }; 30 31 static DEFINE_PER_CPU(struct cpu_info, cpu_info); 32 33 static bool machine_has_cpu_mhz; 34 35 void __init cpu_detect_mhz_feature(void) 36 { 37 if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL) 38 machine_has_cpu_mhz = true; 39 } 40 41 static void update_cpu_mhz(void *arg) 42 { 43 unsigned long mhz; 44 struct cpu_info *c; 45 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; 50 } 51 52 void s390_update_cpu_mhz(void) 53 { 54 s390_adjust_jiffies(); 55 if (machine_has_cpu_mhz) 56 on_each_cpu(update_cpu_mhz, NULL, 0); 57 } 58 59 void notrace cpu_relax_yield(void) 60 { 61 if (!smp_cpu_mtid && MACHINE_HAS_DIAG44) { 62 diag_stat_inc(DIAG_STAT_X044); 63 asm volatile("diag 0,0,0x44"); 64 } 65 barrier(); 66 } 67 EXPORT_SYMBOL(cpu_relax_yield); 68 69 /* 70 * cpu_init - initializes state that is per-CPU. 71 */ 72 void cpu_init(void) 73 { 74 struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id); 75 76 get_cpu_id(id); 77 if (machine_has_cpu_mhz) 78 update_cpu_mhz(NULL); 79 mmgrab(&init_mm); 80 current->active_mm = &init_mm; 81 BUG_ON(current->mm); 82 enter_lazy_tlb(&init_mm, current); 83 } 84 85 /* 86 * cpu_have_feature - Test CPU features on module initialization 87 */ 88 int cpu_have_feature(unsigned int num) 89 { 90 return elf_hwcap & (1UL << num); 91 } 92 EXPORT_SYMBOL(cpu_have_feature); 93 94 static void show_cpu_summary(struct seq_file *m, void *v) 95 { 96 static const char *hwcap_str[] = { 97 "esan3", "zarch", "stfle", "msa", "ldisp", "eimm", "dfp", 98 "edat", "etf3eh", "highgprs", "te", "vx", "vxd", "vxe" 99 }; 100 static const char * const int_hwcap_str[] = { 101 "sie" 102 }; 103 int i, cpu; 104 105 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]); 118 seq_puts(m, "\n"); 119 show_cacheinfo(m); 120 for_each_online_cpu(cpu) { 121 struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu); 122 123 seq_printf(m, "processor %d: " 124 "version = %02X, " 125 "identification = %06X, " 126 "machine = %04X\n", 127 cpu, id->version, id->ident, id->machine); 128 } 129 } 130 131 static void show_cpu_mhz(struct seq_file *m, unsigned long n) 132 { 133 struct cpu_info *c = per_cpu_ptr(&cpu_info, n); 134 135 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); 137 } 138 139 /* 140 * show_cpuinfo - Get information on one CPU for use by procfs. 141 */ 142 static int show_cpuinfo(struct seq_file *m, void *v) 143 { 144 unsigned long n = (unsigned long) v - 1; 145 146 if (!n) 147 show_cpu_summary(m, v); 148 if (!machine_has_cpu_mhz) 149 return 0; 150 seq_printf(m, "\ncpu number : %ld\n", n); 151 show_cpu_mhz(m, n); 152 return 0; 153 } 154 155 static inline void *c_update(loff_t *pos) 156 { 157 if (*pos) 158 *pos = cpumask_next(*pos - 1, cpu_online_mask); 159 return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL; 160 } 161 162 static void *c_start(struct seq_file *m, loff_t *pos) 163 { 164 get_online_cpus(); 165 return c_update(pos); 166 } 167 168 static void *c_next(struct seq_file *m, void *v, loff_t *pos) 169 { 170 ++*pos; 171 return c_update(pos); 172 } 173 174 static void c_stop(struct seq_file *m, void *v) 175 { 176 put_online_cpus(); 177 } 178 179 const struct seq_operations cpuinfo_op = { 180 .start = c_start, 181 .next = c_next, 182 .stop = c_stop, 183 .show = show_cpuinfo, 184 }; 185