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 "vxe2", "vxp", "sort", "dflt" 114 }; 115 static const char * const int_hwcap_str[] = { 116 "sie" 117 }; 118 int i, cpu; 119 120 seq_printf(m, "vendor_id : IBM/S390\n" 121 "# processors : %i\n" 122 "bogomips per cpu: %lu.%02lu\n", 123 num_online_cpus(), loops_per_jiffy/(500000/HZ), 124 (loops_per_jiffy/(5000/HZ))%100); 125 seq_printf(m, "max thread id : %d\n", smp_cpu_mtid); 126 seq_puts(m, "features\t: "); 127 for (i = 0; i < ARRAY_SIZE(hwcap_str); i++) 128 if (hwcap_str[i] && (elf_hwcap & (1UL << i))) 129 seq_printf(m, "%s ", hwcap_str[i]); 130 for (i = 0; i < ARRAY_SIZE(int_hwcap_str); i++) 131 if (int_hwcap_str[i] && (int_hwcap & (1UL << i))) 132 seq_printf(m, "%s ", int_hwcap_str[i]); 133 seq_puts(m, "\n"); 134 show_facilities(m); 135 show_cacheinfo(m); 136 for_each_online_cpu(cpu) { 137 struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu); 138 139 seq_printf(m, "processor %d: " 140 "version = %02X, " 141 "identification = %06X, " 142 "machine = %04X\n", 143 cpu, id->version, id->ident, id->machine); 144 } 145 } 146 147 static void show_cpu_mhz(struct seq_file *m, unsigned long n) 148 { 149 struct cpu_info *c = per_cpu_ptr(&cpu_info, n); 150 151 seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic); 152 seq_printf(m, "cpu MHz static : %d\n", c->cpu_mhz_static); 153 } 154 155 /* 156 * show_cpuinfo - Get information on one CPU for use by procfs. 157 */ 158 static int show_cpuinfo(struct seq_file *m, void *v) 159 { 160 unsigned long n = (unsigned long) v - 1; 161 162 if (!n) 163 show_cpu_summary(m, v); 164 if (!machine_has_cpu_mhz) 165 return 0; 166 seq_printf(m, "\ncpu number : %ld\n", n); 167 show_cpu_mhz(m, n); 168 return 0; 169 } 170 171 static inline void *c_update(loff_t *pos) 172 { 173 if (*pos) 174 *pos = cpumask_next(*pos - 1, cpu_online_mask); 175 return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL; 176 } 177 178 static void *c_start(struct seq_file *m, loff_t *pos) 179 { 180 get_online_cpus(); 181 return c_update(pos); 182 } 183 184 static void *c_next(struct seq_file *m, void *v, loff_t *pos) 185 { 186 ++*pos; 187 return c_update(pos); 188 } 189 190 static void c_stop(struct seq_file *m, void *v) 191 { 192 put_online_cpus(); 193 } 194 195 const struct seq_operations cpuinfo_op = { 196 .start = c_start, 197 .next = c_next, 198 .stop = c_stop, 199 .show = show_cpuinfo, 200 }; 201 202 int s390_isolate_bp(void) 203 { 204 if (!test_facility(82)) 205 return -EOPNOTSUPP; 206 set_thread_flag(TIF_ISOLATE_BP); 207 return 0; 208 } 209 EXPORT_SYMBOL(s390_isolate_bp); 210 211 int s390_isolate_bp_guest(void) 212 { 213 if (!test_facility(82)) 214 return -EOPNOTSUPP; 215 set_thread_flag(TIF_ISOLATE_BP_GUEST); 216 return 0; 217 } 218 EXPORT_SYMBOL(s390_isolate_bp_guest); 219