arch/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/cpufeature.h>
  12 #include <linux/bitops.h>
  13 #include <linux/kernel.h>
  14 #include <linux/random.h>
  15 #include <linux/sched/mm.h>
  16 #include <linux/init.h>
  17 #include <linux/seq_file.h>
  18 #include <linux/mm_types.h>
  19 #include <linux/delay.h>
  20 #include <linux/cpu.h>
  21 #include <linux/smp.h>
  22 #include <asm/text-patching.h>
  23 #include <asm/machine.h>
  24 #include <asm/diag.h>
  25 #include <asm/facility.h>
  26 #include <asm/elf.h>
  27 #include <asm/lowcore.h>
  28 #include <asm/param.h>
  29 #include <asm/sclp.h>
  30 #include <asm/smp.h>
  31
  32 unsigned long __read_mostly elf_hwcap;
  33 char elf_platform[ELF_PLATFORM_SIZE];
  34
  35 struct cpu_info {
  36         unsigned int cpu_mhz_dynamic;
  37         unsigned int cpu_mhz_static;
  38         struct cpuid cpu_id;
  39 };
  40
  41 static DEFINE_PER_CPU(struct cpu_info, cpu_info);
  42 static DEFINE_PER_CPU(int, cpu_relax_retry);
  43
  44 static bool machine_has_cpu_mhz;
  45
  46 void __init cpu_detect_mhz_feature(void)
  47 {
  48         if (test_facility(34) && __ecag(ECAG_CPU_ATTRIBUTE, 0) != -1UL)
  49                 machine_has_cpu_mhz = true;
  50 }
  51
  52 static void update_cpu_mhz(void *arg)
  53 {
  54         unsigned long mhz;
  55         struct cpu_info *c;
  56
  57         mhz = __ecag(ECAG_CPU_ATTRIBUTE, 0);
  58         c = this_cpu_ptr(&cpu_info);
  59         c->cpu_mhz_dynamic = mhz >> 32;
  60         c->cpu_mhz_static = mhz & 0xffffffff;
  61 }
  62
  63 void s390_update_cpu_mhz(void)
  64 {
  65         s390_adjust_jiffies();
  66         if (machine_has_cpu_mhz)
  67                 on_each_cpu(update_cpu_mhz, NULL, 0);
  68 }
  69
  70 void notrace stop_machine_yield(const struct cpumask *cpumask)
  71 {
  72         int cpu, this_cpu;
  73
  74         this_cpu = smp_processor_id();
  75         if (__this_cpu_inc_return(cpu_relax_retry) >= spin_retry) {
  76                 __this_cpu_write(cpu_relax_retry, 0);
  77                 cpu = cpumask_next_wrap(this_cpu, cpumask);
  78                 if (cpu >= nr_cpu_ids)
  79                         return;
  80                 if (arch_vcpu_is_preempted(cpu))
  81                         smp_yield_cpu(cpu);
  82         }
  83 }
  84
  85 static void do_sync_core(void *info)
  86 {
  87         sync_core();
  88 }
  89
  90 void text_poke_sync(void)
  91 {
  92         on_each_cpu(do_sync_core, NULL, 1);
  93 }
  94
  95 void text_poke_sync_lock(void)
  96 {
  97         cpus_read_lock();
  98         text_poke_sync();
  99         cpus_read_unlock();
 100 }
 101
 102 /*
 103  * cpu_init - initializes state that is per-CPU.
 104  */
 105 void cpu_init(void)
 106 {
 107         struct cpuid *id = this_cpu_ptr(&cpu_info.cpu_id);
 108
 109         get_cpu_id(id);
 110         if (machine_has_cpu_mhz)
 111                 update_cpu_mhz(NULL);
 112         mmgrab(&init_mm);
 113         current->active_mm = &init_mm;
 114         BUG_ON(current->mm);
 115         enter_lazy_tlb(&init_mm, current);
 116 }
 117
 118 static void show_facilities(struct seq_file *m)
 119 {
 120         unsigned int bit;
 121
 122         seq_puts(m, "facilities      :");
 123         for_each_set_bit_inv(bit, (long *)&stfle_fac_list, MAX_FACILITY_BIT)
 124                 seq_printf(m, " %d", bit);
 125         seq_putc(m, '\n');
 126 }
 127
 128 static void show_cpu_summary(struct seq_file *m, void *v)
 129 {
 130         static const char *hwcap_str[] = {
 131                 [HWCAP_NR_ESAN3]        = "esan3",
 132                 [HWCAP_NR_ZARCH]        = "zarch",
 133                 [HWCAP_NR_STFLE]        = "stfle",
 134                 [HWCAP_NR_MSA]          = "msa",
 135                 [HWCAP_NR_LDISP]        = "ldisp",
 136                 [HWCAP_NR_EIMM]         = "eimm",
 137                 [HWCAP_NR_DFP]          = "dfp",
 138                 [HWCAP_NR_HPAGE]        = "edat",
 139                 [HWCAP_NR_ETF3EH]       = "etf3eh",
 140                 [HWCAP_NR_HIGH_GPRS]    = "highgprs",
 141                 [HWCAP_NR_TE]           = "te",
 142                 [HWCAP_NR_VXRS]         = "vx",
 143                 [HWCAP_NR_VXRS_BCD]     = "vxd",
 144                 [HWCAP_NR_VXRS_EXT]     = "vxe",
 145                 [HWCAP_NR_GS]           = "gs",
 146                 [HWCAP_NR_VXRS_EXT2]    = "vxe2",
 147                 [HWCAP_NR_VXRS_PDE]     = "vxp",
 148                 [HWCAP_NR_SORT]         = "sort",
 149                 [HWCAP_NR_DFLT]         = "dflt",
 150                 [HWCAP_NR_VXRS_PDE2]    = "vxp2",
 151                 [HWCAP_NR_NNPA]         = "nnpa",
 152                 [HWCAP_NR_PCI_MIO]      = "pcimio",
 153                 [HWCAP_NR_SIE]          = "sie",
 154         };
 155         int i, cpu;
 156
 157         BUILD_BUG_ON(ARRAY_SIZE(hwcap_str) != HWCAP_NR_MAX);
 158         seq_printf(m, "vendor_id       : IBM/S390\n"
 159                    "# processors    : %i\n"
 160                    "bogomips per cpu: %lu.%02lu\n",
 161                    num_online_cpus(), loops_per_jiffy/(500000/HZ),
 162                    (loops_per_jiffy/(5000/HZ))%100);
 163         seq_printf(m, "max thread id   : %d\n", smp_cpu_mtid);
 164         seq_puts(m, "features\t: ");
 165         for (i = 0; i < ARRAY_SIZE(hwcap_str); i++)
 166                 if (hwcap_str[i] && (elf_hwcap & (1UL << i)))
 167                         seq_printf(m, "%s ", hwcap_str[i]);
 168         seq_puts(m, "\n");
 169         show_facilities(m);
 170         show_cacheinfo(m);
 171         for_each_online_cpu(cpu) {
 172                 struct cpuid *id = &per_cpu(cpu_info.cpu_id, cpu);
 173
 174                 seq_printf(m, "processor %d: "
 175                            "version = %02X,  "
 176                            "identification = %06X,  "
 177                            "machine = %04X\n",
 178                            cpu, id->version, id->ident, id->machine);
 179         }
 180 }
 181
 182 static int __init setup_hwcaps(void)
 183 {
 184         /* instructions named N3, "backported" to esa-mode */
 185         elf_hwcap |= HWCAP_ESAN3;
 186
 187         /* z/Architecture mode active */
 188         elf_hwcap |= HWCAP_ZARCH;
 189
 190         /* store-facility-list-extended */
 191         if (test_facility(7))
 192                 elf_hwcap |= HWCAP_STFLE;
 193
 194         /* message-security assist */
 195         if (test_facility(17))
 196                 elf_hwcap |= HWCAP_MSA;
 197
 198         /* long-displacement */
 199         if (test_facility(19))
 200                 elf_hwcap |= HWCAP_LDISP;
 201
 202         /* extended-immediate */
 203         elf_hwcap |= HWCAP_EIMM;
 204
 205         /* extended-translation facility 3 enhancement */
 206         if (test_facility(22) && test_facility(30))
 207                 elf_hwcap |= HWCAP_ETF3EH;
 208
 209         /* decimal floating point & perform floating point operation */
 210         if (test_facility(42) && test_facility(44))
 211                 elf_hwcap |= HWCAP_DFP;
 212
 213         /* huge page support */
 214         if (cpu_has_edat1())
 215                 elf_hwcap |= HWCAP_HPAGE;
 216
 217         /* 64-bit register support for 31-bit processes */
 218         elf_hwcap |= HWCAP_HIGH_GPRS;
 219
 220         /* transactional execution */
 221         if (machine_has_tx())
 222                 elf_hwcap |= HWCAP_TE;
 223
 224         /* vector */
 225         if (test_facility(129)) {
 226                 elf_hwcap |= HWCAP_VXRS;
 227                 if (test_facility(134))
 228                         elf_hwcap |= HWCAP_VXRS_BCD;
 229                 if (test_facility(135))
 230                         elf_hwcap |= HWCAP_VXRS_EXT;
 231                 if (test_facility(148))
 232                         elf_hwcap |= HWCAP_VXRS_EXT2;
 233                 if (test_facility(152))
 234                         elf_hwcap |= HWCAP_VXRS_PDE;
 235                 if (test_facility(192))
 236                         elf_hwcap |= HWCAP_VXRS_PDE2;
 237         }
 238
 239         if (test_facility(150))
 240                 elf_hwcap |= HWCAP_SORT;
 241
 242         if (test_facility(151))
 243                 elf_hwcap |= HWCAP_DFLT;
 244
 245         if (test_facility(165))
 246                 elf_hwcap |= HWCAP_NNPA;
 247
 248         /* guarded storage */
 249         if (cpu_has_gs())
 250                 elf_hwcap |= HWCAP_GS;
 251
 252         if (test_machine_feature(MFEATURE_PCI_MIO))
 253                 elf_hwcap |= HWCAP_PCI_MIO;
 254
 255         /* virtualization support */
 256         if (sclp.has_sief2)
 257                 elf_hwcap |= HWCAP_SIE;
 258
 259         return 0;
 260 }
 261 arch_initcall(setup_hwcaps);
 262
 263 static int __init setup_elf_platform(void)
 264 {
 265         struct cpuid cpu_id;
 266
 267         get_cpu_id(&cpu_id);
 268         add_device_randomness(&cpu_id, sizeof(cpu_id));
 269         switch (cpu_id.machine) {
 270         default:        /* Use "z10" as default. */
 271                 strscpy(elf_platform, "z10");
 272                 break;
 273         case 0x2817:
 274         case 0x2818:
 275                 strscpy(elf_platform, "z196");
 276                 break;
 277         case 0x2827:
 278         case 0x2828:
 279                 strscpy(elf_platform, "zEC12");
 280                 break;
 281         case 0x2964:
 282         case 0x2965:
 283                 strscpy(elf_platform, "z13");
 284                 break;
 285         case 0x3906:
 286         case 0x3907:
 287                 strscpy(elf_platform, "z14");
 288                 break;
 289         case 0x8561:
 290         case 0x8562:
 291                 strscpy(elf_platform, "z15");
 292                 break;
 293         case 0x3931:
 294         case 0x3932:
 295                 strscpy(elf_platform, "z16");
 296                 break;
 297         case 0x9175:
 298         case 0x9176:
 299                 strscpy(elf_platform, "z17");
 300                 break;
 301         }
 302         return 0;
 303 }
 304 arch_initcall(setup_elf_platform);
 305
 306 static void show_cpu_topology(struct seq_file *m, unsigned long n)
 307 {
 308 #ifdef CONFIG_SCHED_TOPOLOGY
 309         seq_printf(m, "physical id     : %d\n", topology_physical_package_id(n));
 310         seq_printf(m, "core id         : %d\n", topology_core_id(n));
 311         seq_printf(m, "book id         : %d\n", topology_book_id(n));
 312         seq_printf(m, "drawer id       : %d\n", topology_drawer_id(n));
 313         seq_printf(m, "dedicated       : %d\n", topology_cpu_dedicated(n));
 314         seq_printf(m, "address         : %d\n", smp_cpu_get_cpu_address(n));
 315         seq_printf(m, "siblings        : %d\n", cpumask_weight(topology_core_cpumask(n)));
 316         seq_printf(m, "cpu cores       : %d\n", topology_booted_cores(n));
 317 #endif /* CONFIG_SCHED_TOPOLOGY */
 318 }
 319
 320 static void show_cpu_ids(struct seq_file *m, unsigned long n)
 321 {
 322         struct cpuid *id = &per_cpu(cpu_info.cpu_id, n);
 323
 324         seq_printf(m, "version         : %02X\n", id->version);
 325         seq_printf(m, "identification  : %06X\n", id->ident);
 326         seq_printf(m, "machine         : %04X\n", id->machine);
 327 }
 328
 329 static void show_cpu_mhz(struct seq_file *m, unsigned long n)
 330 {
 331         struct cpu_info *c = per_cpu_ptr(&cpu_info, n);
 332
 333         if (!machine_has_cpu_mhz)
 334                 return;
 335         seq_printf(m, "cpu MHz dynamic : %d\n", c->cpu_mhz_dynamic);
 336         seq_printf(m, "cpu MHz static  : %d\n", c->cpu_mhz_static);
 337 }
 338
 339 /*
 340  * show_cpuinfo - Get information on one CPU for use by procfs.
 341  */
 342 static int show_cpuinfo(struct seq_file *m, void *v)
 343 {
 344         unsigned long n = (unsigned long) v - 1;
 345         unsigned long first = cpumask_first(cpu_online_mask);
 346
 347         if (n == first)
 348                 show_cpu_summary(m, v);
 349         seq_printf(m, "\ncpu number      : %ld\n", n);
 350         show_cpu_topology(m, n);
 351         show_cpu_ids(m, n);
 352         show_cpu_mhz(m, n);
 353         return 0;
 354 }
 355
 356 static inline void *c_update(loff_t *pos)
 357 {
 358         if (*pos)
 359                 *pos = cpumask_next(*pos - 1, cpu_online_mask);
 360         else
 361                 *pos = cpumask_first(cpu_online_mask);
 362         return *pos < nr_cpu_ids ? (void *)*pos + 1 : NULL;
 363 }
 364
 365 static void *c_start(struct seq_file *m, loff_t *pos)
 366 {
 367         cpus_read_lock();
 368         return c_update(pos);
 369 }
 370
 371 static void *c_next(struct seq_file *m, void *v, loff_t *pos)
 372 {
 373         ++*pos;
 374         return c_update(pos);
 375 }
 376
 377 static void c_stop(struct seq_file *m, void *v)
 378 {
 379         cpus_read_unlock();
 380 }
 381
 382 const struct seq_operations cpuinfo_op = {
 383         .start  = c_start,
 384         .next   = c_next,
 385         .stop   = c_stop,
 386         .show   = show_cpuinfo,
 387 };