s390/kernel/processor.c

   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/stop_machine.h>
  11 #include <linux/bitops.h>
  12 #include <linux/kernel.h>
  13 #include <linux/random.h>
  14 #include <linux/sched/mm.h>
  15 #include <linux/init.h>
  16 #include <linux/seq_file.h>
  17 #include <linux/mm_types.h>
  18 #include <linux/delay.h>
  19 #include <linux/cpu.h>
  20
  21 #include <asm/diag.h>
  22 #include <asm/facility.h>
  23 #include <asm/elf.h>
  24 #include <asm/lowcore.h>
  25 #include <asm/param.h>
  26 #include <asm/sclp.h>
  27 #include <asm/smp.h>
  28
  29 unsigned long __read_mostly elf_hwcap;
  30 char elf_platform[ELF_PLATFORM_SIZE];
  31
  32 struct cpu_info {
  33         unsigned int cpu_mhz_dynamic;
  34         unsigned int cpu_mhz_static;
  35         struct cpuid cpu_id;
  36 };
  37
  38 static DEFINE_PER_CPU(struct cpu_info, cpu_info);
  39 static DEFINE_PER_CPU(int, cpu_relax_retry);
  40
  41 static bool machine_has_cpu_mhz;
  42
  43 void __init cpu_detect_mhz_feature(void)
  44 {
  45         if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL)
  46                 machine_has_cpu_mhz = true;
  47 }
  48
  49 static void update_cpu_mhz(void *arg)
  50 {
  51         unsigned long mhz;
  52         struct cpu_info *c;
  53
  54         mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0);
  55         c = this_cpu_ptr(&cpu_info);
  56         c->cpu_mhz_dynamic = mhz >> 32;
  57         c->cpu_mhz_static = mhz & 0xffffffff;
  58 }
  59
  60 void s390_update_cpu_mhz(void)
  61 {
  62         s390_adjust_jiffies();
  63         if (machine_has_cpu_mhz)
  64                 on_each_cpu(update_cpu_mhz, NULL, 0);
  65 }
  66
  67 void notrace stop_machine_yield(const struct cpumask *cpumask)
  68 {
  69         int cpu, this_cpu;
  70
  71         this_cpu = smp_processor_id();
  72         if (__this_cpu_inc_return(cpu_relax_retry) >= spin_retry) {
  73                 __this_cpu_write(cpu_relax_retry, 0);
  74                 cpu = cpumask_next_wrap(this_cpu, cpumask, this_cpu, false);
  75                 if (cpu >= nr_cpu_ids)
  76                         return;
  77                 if (arch_vcpu_is_preempted(cpu))
  78                         smp_yield_cpu(cpu);
  79         }
  80 }
  81
  82 /*
  83  * cpu_init - initializes state that is per-CPU.
  84  */
  85 void cpu_init(void)
  86 {
  87         struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id);
  88
  89         get_cpu_id(id);
  90         if (machine_has_cpu_mhz)
  91                 update_cpu_mhz(NULL);
  92         mmgrab(&init_mm);
  93         current->active_mm = &init_mm;
  94         BUG_ON(current->mm);
  95         enter_lazy_tlb(&init_mm, current);
  96 }
  97
  98 static void show_facilities(struct seq_file *m)
  99 {
 100         unsigned int bit;
 101
 102         seq_puts(m, "facilities      :");
 103         for_each_set_bit_inv(bit, (long *)&stfle_fac_list, 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                 [HWCAP_NR_ESAN3]        = "esan3",
 112                 [HWCAP_NR_ZARCH]        = "zarch",
 113                 [HWCAP_NR_STFLE]        = "stfle",
 114                 [HWCAP_NR_MSA]          = "msa",
 115                 [HWCAP_NR_LDISP]        = "ldisp",
 116                 [HWCAP_NR_EIMM]         = "eimm",
 117                 [HWCAP_NR_DFP]          = "dfp",
 118                 [HWCAP_NR_HPAGE]        = "edat",
 119                 [HWCAP_NR_ETF3EH]       = "etf3eh",
 120                 [HWCAP_NR_HIGH_GPRS]    = "highgprs",
 121                 [HWCAP_NR_TE]           = "te",
 122                 [HWCAP_NR_VXRS]         = "vx",
 123                 [HWCAP_NR_VXRS_BCD]     = "vxd",
 124                 [HWCAP_NR_VXRS_EXT]     = "vxe",
 125                 [HWCAP_NR_GS]           = "gs",
 126                 [HWCAP_NR_VXRS_EXT2]    = "vxe2",
 127                 [HWCAP_NR_VXRS_PDE]     = "vxp",
 128                 [HWCAP_NR_SORT]         = "sort",
 129                 [HWCAP_NR_DFLT]         = "dflt",
 130                 [HWCAP_NR_VXRS_PDE2]    = "vxp2",
 131                 [HWCAP_NR_NNPA]         = "nnpa",
 132                 [HWCAP_NR_PCI_MIO]      = "pcimio",
 133                 [HWCAP_NR_SIE]          = "sie",
 134         };
 135         int i, cpu;
 136
 137         BUILD_BUG_ON(ARRAY_SIZE(hwcap_str) != HWCAP_NR_MAX);
 138         seq_printf(m, "vendor_id       : IBM/S390\n"
 139                    "# processors    : %i\n"
 140                    "bogomips per cpu: %lu.%02lu\n",
 141                    num_online_cpus(), loops_per_jiffy/(500000/HZ),
 142                    (loops_per_jiffy/(5000/HZ))%100);
 143         seq_printf(m, "max thread id   : %d\n", smp_cpu_mtid);
 144         seq_puts(m, "features\t: ");
 145         for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
 146                 if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
 147                         seq_printf(m, "%s ", hwcap_str[i]);
 148         seq_puts(m, "\n");
 149         show_facilities(m);
 150         show_cacheinfo(m);
 151         for_each_online_cpu(cpu) {
 152                 struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu);
 153
 154                 seq_printf(m, "processor %d: "
 155                            "version = %02X,  "
 156                            "identification = %06X,  "
 157                            "machine = %04X\n",
 158                            cpu, id->version, id->ident, id->machine);
 159         }
 160 }
 161
 162 static int __init setup_hwcaps(void)
 163 {
 164         /* instructions named N3, "backported" to esa-mode */
 165         elf_hwcap |= HWCAP_ESAN3;
 166
 167         /* z/Architecture mode active */
 168         elf_hwcap |= HWCAP_ZARCH;
 169
 170         /* store-facility-list-extended */
 171         if (test_facility(7))
 172                 elf_hwcap |= HWCAP_STFLE;
 173
 174         /* message-security assist */
 175         if (test_facility(17))
 176                 elf_hwcap |= HWCAP_MSA;
 177
 178         /* long-displacement */
 179         if (test_facility(19))
 180                 elf_hwcap |= HWCAP_LDISP;
 181
 182         /* extended-immediate */
 183         elf_hwcap |= HWCAP_EIMM;
 184
 185         /* extended-translation facility 3 enhancement */
 186         if (test_facility(22) && test_facility(30))
 187                 elf_hwcap |= HWCAP_ETF3EH;
 188
 189         /* decimal floating point & perform floating point operation */
 190         if (test_facility(42) && test_facility(44))
 191                 elf_hwcap |= HWCAP_DFP;
 192
 193         /* huge page support */
 194         if (MACHINE_HAS_EDAT1)
 195                 elf_hwcap |= HWCAP_HPAGE;
 196
 197         /* 64-bit register support for 31-bit processes */
 198         elf_hwcap |= HWCAP_HIGH_GPRS;
 199
 200         /* transactional execution */
 201         if (MACHINE_HAS_TE)
 202                 elf_hwcap |= HWCAP_TE;
 203
 204         /*
 205          * Vector extension can be disabled with the "novx" parameter.
 206          * Use MACHINE_HAS_VX instead of facility bit 129.
 207          */
 208         if (MACHINE_HAS_VX) {
 209                 elf_hwcap |= HWCAP_VXRS;
 210                 if (test_facility(134))
 211                         elf_hwcap |= HWCAP_VXRS_BCD;
 212                 if (test_facility(135))
 213                         elf_hwcap |= HWCAP_VXRS_EXT;
 214                 if (test_facility(148))
 215                         elf_hwcap |= HWCAP_VXRS_EXT2;
 216                 if (test_facility(152))
 217                         elf_hwcap |= HWCAP_VXRS_PDE;
 218                 if (test_facility(192))
 219                         elf_hwcap |= HWCAP_VXRS_PDE2;
 220         }
 221
 222         if (test_facility(150))
 223                 elf_hwcap |= HWCAP_SORT;
 224
 225         if (test_facility(151))
 226                 elf_hwcap |= HWCAP_DFLT;
 227
 228         if (test_facility(165))
 229                 elf_hwcap |= HWCAP_NNPA;
 230
 231         /* guarded storage */
 232         if (MACHINE_HAS_GS)
 233                 elf_hwcap |= HWCAP_GS;
 234
 235         if (MACHINE_HAS_PCI_MIO)
 236                 elf_hwcap |= HWCAP_PCI_MIO;
 237
 238         /* virtualization support */
 239         if (sclp.has_sief2)
 240                 elf_hwcap |= HWCAP_SIE;
 241
 242         return 0;
 243 }
 244 arch_initcall(setup_hwcaps);
 245
 246 static int __init setup_elf_platform(void)
 247 {
 248         struct cpuid cpu_id;
 249
 250         get_cpu_id(&cpu_id);
 251         add_device_randomness(&cpu_id, sizeof(cpu_id));
 252         switch (cpu_id.machine) {
 253         default:        /* Use "z10" as default. */
 254                 strcpy(elf_platform, "z10");
 255                 break;
 256         case 0x2817:
 257         case 0x2818:
 258                 strcpy(elf_platform, "z196");
 259                 break;
 260         case 0x2827:
 261         case 0x2828:
 262                 strcpy(elf_platform, "zEC12");
 263                 break;
 264         case 0x2964:
 265         case 0x2965:
 266                 strcpy(elf_platform, "z13");
 267                 break;
 268         case 0x3906:
 269         case 0x3907:
 270                 strcpy(elf_platform, "z14");
 271                 break;
 272         case 0x8561:
 273         case 0x8562:
 274                 strcpy(elf_platform, "z15");
 275                 break;
 276         case 0x3931:
 277         case 0x3932:
 278                 strcpy(elf_platform, "z16");
 279                 break;
 280         }
 281         return 0;
 282 }
 283 arch_initcall(setup_elf_platform);
 284
 285 static void show_cpu_topology(struct seq_file *m, unsigned long n)
 286 {
 287 #ifdef CONFIG_SCHED_TOPOLOGY
 288         seq_printf(m, "physical id     : %d\n", topology_physical_package_id(n));
 289         seq_printf(m, "core id         : %d\n", topology_core_id(n));
 290         seq_printf(m, "book id         : %d\n", topology_book_id(n));
 291         seq_printf(m, "drawer id       : %d\n", topology_drawer_id(n));
 292         seq_printf(m, "dedicated       : %d\n", topology_cpu_dedicated(n));
 293         seq_printf(m, "address         : %d\n", smp_cpu_get_cpu_address(n));
 294         seq_printf(m, "siblings        : %d\n", cpumask_weight(topology_core_cpumask(n)));
 295         seq_printf(m, "cpu cores       : %d\n", topology_booted_cores(n));
 296 #endif /* CONFIG_SCHED_TOPOLOGY */
 297 }
 298
 299 static void show_cpu_ids(struct seq_file *m, unsigned long n)
 300 {
 301         struct cpuid *id = &per_cpu(cpu_info.cpu_id, n);
 302
 303         seq_printf(m, "version         : %02X\n", id->version);
 304         seq_printf(m, "identification  : %06X\n", id->ident);
 305         seq_printf(m, "machine         : %04X\n", id->machine);
 306 }
 307
 308 static void show_cpu_mhz(struct seq_file *m, unsigned long n)
 309 {
 310         struct cpu_info *c = per_cpu_ptr(&cpu_info, n);
 311
 312         if (!machine_has_cpu_mhz)
 313                 return;
 314         seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic);
 315         seq_printf(m, "cpu MHz static  : %d\n", c->cpu_mhz_static);
 316 }
 317
 318 /*
 319  * show_cpuinfo - Get information on one CPU for use by procfs.
 320  */
 321 static int show_cpuinfo(struct seq_file *m, void *v)
 322 {
 323         unsigned long n = (unsigned long) v - 1;
 324         unsigned long first = cpumask_first(cpu_online_mask);
 325
 326         if (n == first)
 327                 show_cpu_summary(m, v);
 328         seq_printf(m, "\ncpu number      : %ld\n", n);
 329         show_cpu_topology(m, n);
 330         show_cpu_ids(m, n);
 331         show_cpu_mhz(m, n);
 332         return 0;
 333 }
 334
 335 static inline void *c_update(loff_t *pos)
 336 {
 337         if (*pos)
 338                 *pos = cpumask_next(*pos - 1, cpu_online_mask);
 339         else
 340                 *pos = cpumask_first(cpu_online_mask);
 341         return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
 342 }
 343
 344 static void *c_start(struct seq_file *m, loff_t *pos)
 345 {
 346         cpus_read_lock();
 347         return c_update(pos);
 348 }
 349
 350 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 351 {
 352         ++*pos;
 353         return c_update(pos);
 354 }
 355
 356 static void c_stop(struct seq_file *m, void *v)
 357 {
 358         cpus_read_unlock();
 359 }
 360
 361 const struct seq_operations cpuinfo_op = {
 362         .start  = c_start,
 363         .next   = c_next,
 364         .stop   = c_stop,
 365         .show   = show_cpuinfo,
 366 };
 367
 368 int s390_isolate_bp(void)
 369 {
 370         if (!test_facility(82))
 371                 return -EOPNOTSUPP;
 372         set_thread_flag(TIF_ISOLATE_BP);
 373         return 0;
 374 }
 375 EXPORT_SYMBOL(s390_isolate_bp);
 376
 377 int s390_isolate_bp_guest(void)
 378 {
 379         if (!test_facility(82))
 380                 return -EOPNOTSUPP;
 381         set_thread_flag(TIF_ISOLATE_BP_GUEST);
 382         return 0;
 383 }
 384 EXPORT_SYMBOL(s390_isolate_bp_guest);