arch/powerpc/kernel/sysfs.c

   1 #include <linux/sysdev.h>
   2 #include <linux/cpu.h>
   3 #include <linux/smp.h>
   4 #include <linux/percpu.h>
   5 #include <linux/init.h>
   6 #include <linux/sched.h>
   7 #include <linux/module.h>
   8 #include <linux/nodemask.h>
   9 #include <linux/cpumask.h>
  10 #include <linux/notifier.h>
  11
  12 #include <asm/current.h>
  13 #include <asm/processor.h>
  14 #include <asm/cputable.h>
  15 #include <asm/firmware.h>
  16 #include <asm/hvcall.h>
  17 #include <asm/prom.h>
  18 #include <asm/paca.h>
  19 #include <asm/lppaca.h>
  20 #include <asm/machdep.h>
  21 #include <asm/smp.h>
  22
  23 static DEFINE_PER_CPU(struct cpu, cpu_devices);
  24
  25 /* SMT stuff */
  26
  27 #ifdef CONFIG_PPC_MULTIPLATFORM
  28 /* Time in microseconds we delay before sleeping in the idle loop */
  29 DEFINE_PER_CPU(unsigned long, smt_snooze_delay) = { 100 };
  30
  31 static ssize_t store_smt_snooze_delay(struct sys_device *dev, const char *buf,
  32                                       size_t count)
  33 {
  34         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
  35         ssize_t ret;
  36         unsigned long snooze;
  37
  38         ret = sscanf(buf, "%lu", &snooze);
  39         if (ret != 1)
  40                 return -EINVAL;
  41
  42         per_cpu(smt_snooze_delay, cpu->sysdev.id) = snooze;
  43
  44         return count;
  45 }
  46
  47 static ssize_t show_smt_snooze_delay(struct sys_device *dev, char *buf)
  48 {
  49         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
  50
  51         return sprintf(buf, "%lu\n", per_cpu(smt_snooze_delay, cpu->sysdev.id));
  52 }
  53
  54 static SYSDEV_ATTR(smt_snooze_delay, 0644, show_smt_snooze_delay,
  55                    store_smt_snooze_delay);
  56
  57 /* Only parse OF options if the matching cmdline option was not specified */
  58 static int smt_snooze_cmdline;
  59
  60 static int __init smt_setup(void)
  61 {
  62         struct device_node *options;
  63         const unsigned int *val;
  64         unsigned int cpu;
  65
  66         if (!cpu_has_feature(CPU_FTR_SMT))
  67                 return -ENODEV;
  68
  69         options = find_path_device("/options");
  70         if (!options)
  71                 return -ENODEV;
  72
  73         val = of_get_property(options, "ibm,smt-snooze-delay", NULL);
  74         if (!smt_snooze_cmdline && val) {
  75                 for_each_possible_cpu(cpu)
  76                         per_cpu(smt_snooze_delay, cpu) = *val;
  77         }
  78
  79         return 0;
  80 }
  81 __initcall(smt_setup);
  82
  83 static int __init setup_smt_snooze_delay(char *str)
  84 {
  85         unsigned int cpu;
  86         int snooze;
  87
  88         if (!cpu_has_feature(CPU_FTR_SMT))
  89                 return 1;
  90
  91         smt_snooze_cmdline = 1;
  92
  93         if (get_option(&str, &snooze)) {
  94                 for_each_possible_cpu(cpu)
  95                         per_cpu(smt_snooze_delay, cpu) = snooze;
  96         }
  97
  98         return 1;
  99 }
 100 __setup("smt-snooze-delay=", setup_smt_snooze_delay);
 101
 102 #endif /* CONFIG_PPC_MULTIPLATFORM */
 103
 104 /*
 105  * Enabling PMCs will slow partition context switch times so we only do
 106  * it the first time we write to the PMCs.
 107  */
 108
 109 static DEFINE_PER_CPU(char, pmcs_enabled);
 110
 111 void ppc64_enable_pmcs(void)
 112 {
 113         /* Only need to enable them once */
 114         if (__get_cpu_var(pmcs_enabled))
 115                 return;
 116
 117         __get_cpu_var(pmcs_enabled) = 1;
 118
 119         if (ppc_md.enable_pmcs)
 120                 ppc_md.enable_pmcs();
 121 }
 122 EXPORT_SYMBOL(ppc64_enable_pmcs);
 123
 124 /* XXX convert to rusty's on_one_cpu */
 125 static unsigned long run_on_cpu(unsigned long cpu,
 126                                 unsigned long (*func)(unsigned long),
 127                                 unsigned long arg)
 128 {
 129         cpumask_t old_affinity = current->cpus_allowed;
 130         unsigned long ret;
 131
 132         /* should return -EINVAL to userspace */
 133         if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
 134                 return 0;
 135
 136         ret = func(arg);
 137
 138         set_cpus_allowed(current, old_affinity);
 139
 140         return ret;
 141 }
 142
 143 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
 144 static unsigned long read_##NAME(unsigned long junk) \
 145 { \
 146         return mfspr(ADDRESS); \
 147 } \
 148 static unsigned long write_##NAME(unsigned long val) \
 149 { \
 150         ppc64_enable_pmcs(); \
 151         mtspr(ADDRESS, val); \
 152         return 0; \
 153 } \
 154 static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
 155 { \
 156         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 157         unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
 158         return sprintf(buf, "%lx\n", val); \
 159 } \
 160 static ssize_t __attribute_used__ \
 161         store_##NAME(struct sys_device *dev, const char *buf, size_t count) \
 162 { \
 163         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 164         unsigned long val; \
 165         int ret = sscanf(buf, "%lx", &val); \
 166         if (ret != 1) \
 167                 return -EINVAL; \
 168         run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
 169         return count; \
 170 }
 171
 172
 173 /* Let's define all possible registers, we'll only hook up the ones
 174  * that are implemented on the current processor
 175  */
 176
 177 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 178 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 179 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 180 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 181 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 182 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 183 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 184 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 185 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 186 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 187 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 188 SYSFS_PMCSETUP(purr, SPRN_PURR);
 189 SYSFS_PMCSETUP(spurr, SPRN_SPURR);
 190 SYSFS_PMCSETUP(dscr, SPRN_DSCR);
 191
 192 SYSFS_PMCSETUP(pa6t_pmc0, PA6T_SPRN_PMC0);
 193 SYSFS_PMCSETUP(pa6t_pmc1, PA6T_SPRN_PMC1);
 194 SYSFS_PMCSETUP(pa6t_pmc2, PA6T_SPRN_PMC2);
 195 SYSFS_PMCSETUP(pa6t_pmc3, PA6T_SPRN_PMC3);
 196 SYSFS_PMCSETUP(pa6t_pmc4, PA6T_SPRN_PMC4);
 197 SYSFS_PMCSETUP(pa6t_pmc5, PA6T_SPRN_PMC5);
 198
 199
 200 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 201 static SYSDEV_ATTR(spurr, 0600, show_spurr, NULL);
 202 static SYSDEV_ATTR(dscr, 0600, show_dscr, store_dscr);
 203 static SYSDEV_ATTR(purr, 0600, show_purr, store_purr);
 204
 205 static struct sysdev_attribute ibm_common_attrs[] = {
 206         _SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
 207         _SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
 208 };
 209
 210 static struct sysdev_attribute ibm_pmc_attrs[] = {
 211         _SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1),
 212         _SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2),
 213         _SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3),
 214         _SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4),
 215         _SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5),
 216         _SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6),
 217         _SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7),
 218         _SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8),
 219 };
 220
 221 static struct sysdev_attribute pa6t_attrs[] = {
 222         _SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
 223         _SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
 224         _SYSDEV_ATTR(pmc0, 0600, show_pa6t_pmc0, store_pa6t_pmc0),
 225         _SYSDEV_ATTR(pmc1, 0600, show_pa6t_pmc1, store_pa6t_pmc1),
 226         _SYSDEV_ATTR(pmc2, 0600, show_pa6t_pmc2, store_pa6t_pmc2),
 227         _SYSDEV_ATTR(pmc3, 0600, show_pa6t_pmc3, store_pa6t_pmc3),
 228         _SYSDEV_ATTR(pmc4, 0600, show_pa6t_pmc4, store_pa6t_pmc4),
 229         _SYSDEV_ATTR(pmc5, 0600, show_pa6t_pmc5, store_pa6t_pmc5),
 230 };
 231
 232
 233 static void register_cpu_online(unsigned int cpu)
 234 {
 235         struct cpu *c = &per_cpu(cpu_devices, cpu);
 236         struct sys_device *s = &c->sysdev;
 237         struct sysdev_attribute *attrs, *pmc_attrs;
 238         int i, nattrs;
 239
 240         if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
 241                         cpu_has_feature(CPU_FTR_SMT))
 242                 sysdev_create_file(s, &attr_smt_snooze_delay);
 243
 244         /* PMC stuff */
 245         switch (cur_cpu_spec->pmc_type) {
 246         case PPC_PMC_IBM:
 247                 attrs = ibm_common_attrs;
 248                 nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
 249                 pmc_attrs = ibm_pmc_attrs;
 250                 break;
 251         case PPC_PMC_PA6T:
 252                 /* PA Semi starts counting at PMC0 */
 253                 attrs = pa6t_attrs;
 254                 nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
 255                 pmc_attrs = NULL;
 256                 break;
 257         default:
 258                 attrs = NULL;
 259                 nattrs = 0;
 260                 pmc_attrs = NULL;
 261         }
 262
 263         for (i = 0; i < nattrs; i++)
 264                 sysdev_create_file(s, &attrs[i]);
 265
 266         if (pmc_attrs)
 267                 for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
 268                         sysdev_create_file(s, &pmc_attrs[i]);
 269
 270         if (cpu_has_feature(CPU_FTR_MMCRA))
 271                 sysdev_create_file(s, &attr_mmcra);
 272
 273         if (cpu_has_feature(CPU_FTR_PURR))
 274                 sysdev_create_file(s, &attr_purr);
 275
 276         if (cpu_has_feature(CPU_FTR_SPURR))
 277                 sysdev_create_file(s, &attr_spurr);
 278
 279         if (cpu_has_feature(CPU_FTR_DSCR))
 280                 sysdev_create_file(s, &attr_dscr);
 281 }
 282
 283 #ifdef CONFIG_HOTPLUG_CPU
 284 static void unregister_cpu_online(unsigned int cpu)
 285 {
 286         struct cpu *c = &per_cpu(cpu_devices, cpu);
 287         struct sys_device *s = &c->sysdev;
 288         struct sysdev_attribute *attrs, *pmc_attrs;
 289         int i, nattrs;
 290
 291         BUG_ON(!c->hotpluggable);
 292
 293         if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
 294                         cpu_has_feature(CPU_FTR_SMT))
 295                 sysdev_remove_file(s, &attr_smt_snooze_delay);
 296
 297         /* PMC stuff */
 298         switch (cur_cpu_spec->pmc_type) {
 299         case PPC_PMC_IBM:
 300                 attrs = ibm_common_attrs;
 301                 nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
 302                 pmc_attrs = ibm_pmc_attrs;
 303                 break;
 304         case PPC_PMC_PA6T:
 305                 /* PA Semi starts counting at PMC0 */
 306                 attrs = pa6t_attrs;
 307                 nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
 308                 pmc_attrs = NULL;
 309                 break;
 310         default:
 311                 attrs = NULL;
 312                 nattrs = 0;
 313                 pmc_attrs = NULL;
 314         }
 315
 316         for (i = 0; i < nattrs; i++)
 317                 sysdev_remove_file(s, &attrs[i]);
 318
 319         if (pmc_attrs)
 320                 for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
 321                         sysdev_remove_file(s, &pmc_attrs[i]);
 322
 323         if (cpu_has_feature(CPU_FTR_MMCRA))
 324                 sysdev_remove_file(s, &attr_mmcra);
 325
 326         if (cpu_has_feature(CPU_FTR_PURR))
 327                 sysdev_remove_file(s, &attr_purr);
 328
 329         if (cpu_has_feature(CPU_FTR_SPURR))
 330                 sysdev_remove_file(s, &attr_spurr);
 331
 332         if (cpu_has_feature(CPU_FTR_DSCR))
 333                 sysdev_remove_file(s, &attr_dscr);
 334 }
 335 #endif /* CONFIG_HOTPLUG_CPU */
 336
 337 static int __cpuinit sysfs_cpu_notify(struct notifier_block *self,
 338                                       unsigned long action, void *hcpu)
 339 {
 340         unsigned int cpu = (unsigned int)(long)hcpu;
 341
 342         switch (action) {
 343         case CPU_ONLINE:
 344                 register_cpu_online(cpu);
 345                 break;
 346 #ifdef CONFIG_HOTPLUG_CPU
 347         case CPU_DEAD:
 348                 unregister_cpu_online(cpu);
 349                 break;
 350 #endif
 351         }
 352         return NOTIFY_OK;
 353 }
 354
 355 static struct notifier_block __cpuinitdata sysfs_cpu_nb = {
 356         .notifier_call  = sysfs_cpu_notify,
 357 };
 358
 359 static DEFINE_MUTEX(cpu_mutex);
 360
 361 int cpu_add_sysdev_attr(struct sysdev_attribute *attr)
 362 {
 363         int cpu;
 364
 365         mutex_lock(&cpu_mutex);
 366
 367         for_each_possible_cpu(cpu) {
 368                 sysdev_create_file(get_cpu_sysdev(cpu), attr);
 369         }
 370
 371         mutex_unlock(&cpu_mutex);
 372         return 0;
 373 }
 374 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr);
 375
 376 int cpu_add_sysdev_attr_group(struct attribute_group *attrs)
 377 {
 378         int cpu;
 379         struct sys_device *sysdev;
 380
 381         mutex_lock(&cpu_mutex);
 382
 383         for_each_possible_cpu(cpu) {
 384                 sysdev = get_cpu_sysdev(cpu);
 385                 sysfs_create_group(&sysdev->kobj, attrs);
 386         }
 387
 388         mutex_unlock(&cpu_mutex);
 389         return 0;
 390 }
 391 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr_group);
 392
 393
 394 void cpu_remove_sysdev_attr(struct sysdev_attribute *attr)
 395 {
 396         int cpu;
 397
 398         mutex_lock(&cpu_mutex);
 399
 400         for_each_possible_cpu(cpu) {
 401                 sysdev_remove_file(get_cpu_sysdev(cpu), attr);
 402         }
 403
 404         mutex_unlock(&cpu_mutex);
 405 }
 406 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr);
 407
 408 void cpu_remove_sysdev_attr_group(struct attribute_group *attrs)
 409 {
 410         int cpu;
 411         struct sys_device *sysdev;
 412
 413         mutex_lock(&cpu_mutex);
 414
 415         for_each_possible_cpu(cpu) {
 416                 sysdev = get_cpu_sysdev(cpu);
 417                 sysfs_remove_group(&sysdev->kobj, attrs);
 418         }
 419
 420         mutex_unlock(&cpu_mutex);
 421 }
 422 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr_group);
 423
 424
 425 /* NUMA stuff */
 426
 427 #ifdef CONFIG_NUMA
 428 static void register_nodes(void)
 429 {
 430         int i;
 431
 432         for (i = 0; i < MAX_NUMNODES; i++)
 433                 register_one_node(i);
 434 }
 435
 436 int sysfs_add_device_to_node(struct sys_device *dev, int nid)
 437 {
 438         struct node *node = &node_devices[nid];
 439         return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
 440                         kobject_name(&dev->kobj));
 441 }
 442
 443 void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
 444 {
 445         struct node *node = &node_devices[nid];
 446         sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
 447 }
 448
 449 #else
 450 static void register_nodes(void)
 451 {
 452         return;
 453 }
 454
 455 #endif
 456
 457 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
 458 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
 459
 460 /* Only valid if CPU is present. */
 461 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 462 {
 463         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 464
 465         return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
 466 }
 467 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 468
 469 static int __init topology_init(void)
 470 {
 471         int cpu;
 472
 473         register_nodes();
 474         register_cpu_notifier(&sysfs_cpu_nb);
 475
 476         for_each_possible_cpu(cpu) {
 477                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 478
 479                 /*
 480                  * For now, we just see if the system supports making
 481                  * the RTAS calls for CPU hotplug.  But, there may be a
 482                  * more comprehensive way to do this for an individual
 483                  * CPU.  For instance, the boot cpu might never be valid
 484                  * for hotplugging.
 485                  */
 486                 if (ppc_md.cpu_die)
 487                         c->hotpluggable = 1;
 488
 489                 if (cpu_online(cpu) || c->hotpluggable) {
 490                         register_cpu(c, cpu);
 491
 492                         sysdev_create_file(&c->sysdev, &attr_physical_id);
 493                 }
 494
 495                 if (cpu_online(cpu))
 496                         register_cpu_online(cpu);
 497         }
 498
 499         return 0;
 500 }
 501 __initcall(topology_init);