1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright IBM Corp. 2008 4 * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) 5 */ 6 7 #define KMSG_COMPONENT "cpu" 8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 9 10 #include <linux/cpufeature.h> 11 #include <linux/bitops.h> 12 #include <linux/kernel.h> 13 #include <linux/sched/mm.h> 14 #include <linux/init.h> 15 #include <linux/seq_file.h> 16 #include <linux/mm_types.h> 17 #include <linux/delay.h> 18 #include <linux/cpu.h> 19 20 #include <asm/diag.h> 21 #include <asm/facility.h> 22 #include <asm/elf.h> 23 #include <asm/lowcore.h> 24 #include <asm/param.h> 25 #include <asm/smp.h> 26 27 struct cpu_info { 28 unsigned int cpu_mhz_dynamic; 29 unsigned int cpu_mhz_static; 30 struct cpuid cpu_id; 31 }; 32 33 static DEFINE_PER_CPU(struct cpu_info, cpu_info); 34 35 static bool machine_has_cpu_mhz; 36 37 void __init cpu_detect_mhz_feature(void) 38 { 39 if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL) 40 machine_has_cpu_mhz = true; 41 } 42 43 static void update_cpu_mhz(void *arg) 44 { 45 unsigned long mhz; 46 struct cpu_info *c; 47 48 mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0); 49 c = this_cpu_ptr(&cpu_info); 50 c->cpu_mhz_dynamic = mhz >> 32; 51 c->cpu_mhz_static = mhz & 0xffffffff; 52 } 53 54 void s390_update_cpu_mhz(void) 55 { 56 s390_adjust_jiffies(); 57 if (machine_has_cpu_mhz) 58 on_each_cpu(update_cpu_mhz, NULL, 0); 59 } 60 61 void notrace cpu_relax_yield(void) 62 { 63 if (!smp_cpu_mtid && MACHINE_HAS_DIAG44) { 64 diag_stat_inc(DIAG_STAT_X044); 65 asm volatile("diag 0,0,0x44"); 66 } 67 barrier(); 68 } 69 EXPORT_SYMBOL(cpu_relax_yield); 70 71 /* 72 * cpu_init - initializes state that is per-CPU. 73 */ 74 void cpu_init(void) 75 { 76 struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id); 77 78 get_cpu_id(id); 79 if (machine_has_cpu_mhz) 80 update_cpu_mhz(NULL); 81 mmgrab(&init_mm); 82 current->active_mm = &init_mm; 83 BUG_ON(current->mm); 84 enter_lazy_tlb(&init_mm, current); 85 } 86 87 /* 88 * cpu_have_feature - Test CPU features on module initialization 89 */ 90 int cpu_have_feature(unsigned int num) 91 { 92 return elf_hwcap & (1UL << num); 93 } 94 EXPORT_SYMBOL(cpu_have_feature); 95 96 static void show_facilities(struct seq_file *m) 97 { 98 unsigned int bit; 99 long *facilities; 100 101 facilities = (long *)&S390_lowcore.stfle_fac_list; 102 seq_puts(m, "facilities :"); 103 for_each_set_bit_inv(bit, facilities, MAX_FACILITY_BIT) 104 seq_printf(m, " %d", bit); 105 seq_putc(m, '\n'); 106 } 107 108 static void show_cpu_summary(struct seq_file *m, void *v) 109 { 110 static const char *hwcap_str[] = { 111 "esan3", "zarch", "stfle", "msa", "ldisp", "eimm", "dfp", 112 "edat", "etf3eh", "highgprs", "te", "vx", "vxd", "vxe", "gs" 113 }; 114 static const char * const int_hwcap_str[] = { 115 "sie" 116 }; 117 int i, cpu; 118 119 seq_printf(m, "vendor_id : IBM/S390\n" 120 "# processors : %i\n" 121 "bogomips per cpu: %lu.%02lu\n", 122 num_online_cpus(), loops_per_jiffy/(500000/HZ), 123 (loops_per_jiffy/(5000/HZ))%100); 124 seq_printf(m, "max thread id : %d\n", smp_cpu_mtid); 125 seq_puts(m, "features\t: "); 126 for (i = 0; i < ARRAY_SIZE(hwcap_str); i++) 127 if (hwcap_str[i] && (elf_hwcap & (1UL << i))) 128 seq_printf(m, "%s ", hwcap_str[i]); 129 for (i = 0; i < ARRAY_SIZE(int_hwcap_str); i++) 130 if (int_hwcap_str[i] && (int_hwcap & (1UL << i))) 131 seq_printf(m, "%s ", int_hwcap_str[i]); 132 seq_puts(m, "\n"); 133 show_facilities(m); 134 show_cacheinfo(m); 135 for_each_online_cpu(cpu) { 136 struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu); 137 138 seq_printf(m, "processor %d: " 139 "version = %02X, " 140 "identification = %06X, " 141 "machine = %04X\n", 142 cpu, id->version, id->ident, id->machine); 143 } 144 } 145 146 static void show_cpu_mhz(struct seq_file *m, unsigned long n) 147 { 148 struct cpu_info *c = per_cpu_ptr(&cpu_info, n); 149 150 seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic); 151 seq_printf(m, "cpu MHz static : %d\n", c->cpu_mhz_static); 152 } 153 154 /* 155 * show_cpuinfo - Get information on one CPU for use by procfs. 156 */ 157 static int show_cpuinfo(struct seq_file *m, void *v) 158 { 159 unsigned long n = (unsigned long) v - 1; 160 161 if (!n) 162 show_cpu_summary(m, v); 163 if (!machine_has_cpu_mhz) 164 return 0; 165 seq_printf(m, "\ncpu number : %ld\n", n); 166 show_cpu_mhz(m, n); 167 return 0; 168 } 169 170 static inline void *c_update(loff_t *pos) 171 { 172 if (*pos) 173 *pos = cpumask_next(*pos - 1, cpu_online_mask); 174 return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL; 175 } 176 177 static void *c_start(struct seq_file *m, loff_t *pos) 178 { 179 get_online_cpus(); 180 return c_update(pos); 181 } 182 183 static void *c_next(struct seq_file *m, void *v, loff_t *pos) 184 { 185 ++*pos; 186 return c_update(pos); 187 } 188 189 static void c_stop(struct seq_file *m, void *v) 190 { 191 put_online_cpus(); 192 } 193 194 const struct seq_operations cpuinfo_op = { 195 .start = c_start, 196 .next = c_next, 197 .stop = c_stop, 198 .show = show_cpuinfo, 199 }; 200 201 int s390_isolate_bp(void) 202 { 203 if (!test_facility(82)) 204 return -EOPNOTSUPP; 205 set_thread_flag(TIF_ISOLATE_BP); 206 return 0; 207 } 208 EXPORT_SYMBOL(s390_isolate_bp); 209 210 int s390_isolate_bp_guest(void) 211 { 212 if (!test_facility(82)) 213 return -EOPNOTSUPP; 214 set_thread_flag(TIF_ISOLATE_BP_GUEST); 215 return 0; 216 } 217 EXPORT_SYMBOL(s390_isolate_bp_guest); 218