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 = of_find_node_by_path("/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         of_node_put(options);
  80         return 0;
  81 }
  82 __initcall(smt_setup);
  83
  84 static int __init setup_smt_snooze_delay(char *str)
  85 {
  86         unsigned int cpu;
  87         int snooze;
  88
  89         if (!cpu_has_feature(CPU_FTR_SMT))
  90                 return 1;
  91
  92         smt_snooze_cmdline = 1;
  93
  94         if (get_option(&str, &snooze)) {
  95                 for_each_possible_cpu(cpu)
  96                         per_cpu(smt_snooze_delay, cpu) = snooze;
  97         }
  98
  99         return 1;
 100 }
 101 __setup("smt-snooze-delay=", setup_smt_snooze_delay);
 102
 103 #endif /* CONFIG_PPC_MULTIPLATFORM */
 104
 105 /*
 106  * Enabling PMCs will slow partition context switch times so we only do
 107  * it the first time we write to the PMCs.
 108  */
 109
 110 static DEFINE_PER_CPU(char, pmcs_enabled);
 111
 112 void ppc64_enable_pmcs(void)
 113 {
 114         /* Only need to enable them once */
 115         if (__get_cpu_var(pmcs_enabled))
 116                 return;
 117
 118         __get_cpu_var(pmcs_enabled) = 1;
 119
 120         if (ppc_md.enable_pmcs)
 121                 ppc_md.enable_pmcs();
 122 }
 123 EXPORT_SYMBOL(ppc64_enable_pmcs);
 124
 125 /* XXX convert to rusty's on_one_cpu */
 126 static unsigned long run_on_cpu(unsigned long cpu,
 127                                 unsigned long (*func)(unsigned long),
 128                                 unsigned long arg)
 129 {
 130         cpumask_t old_affinity = current->cpus_allowed;
 131         unsigned long ret;
 132
 133         /* should return -EINVAL to userspace */
 134         if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
 135                 return 0;
 136
 137         ret = func(arg);
 138
 139         set_cpus_allowed(current, old_affinity);
 140
 141         return ret;
 142 }
 143
 144 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
 145 static unsigned long read_##NAME(unsigned long junk) \
 146 { \
 147         return mfspr(ADDRESS); \
 148 } \
 149 static unsigned long write_##NAME(unsigned long val) \
 150 { \
 151         ppc64_enable_pmcs(); \
 152         mtspr(ADDRESS, val); \
 153         return 0; \
 154 } \
 155 static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
 156 { \
 157         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 158         unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
 159         return sprintf(buf, "%lx\n", val); \
 160 } \
 161 static ssize_t __attribute_used__ \
 162         store_##NAME(struct sys_device *dev, const char *buf, size_t count) \
 163 { \
 164         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 165         unsigned long val; \
 166         int ret = sscanf(buf, "%lx", &val); \
 167         if (ret != 1) \
 168                 return -EINVAL; \
 169         run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
 170         return count; \
 171 }
 172
 173
 174 /* Let's define all possible registers, we'll only hook up the ones
 175  * that are implemented on the current processor
 176  */
 177
 178 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 179 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 180 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 181 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 182 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 183 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 184 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 185 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 186 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 187 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 188 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 189 SYSFS_PMCSETUP(purr, SPRN_PURR);
 190 SYSFS_PMCSETUP(spurr, SPRN_SPURR);
 191 SYSFS_PMCSETUP(dscr, SPRN_DSCR);
 192
 193 SYSFS_PMCSETUP(pa6t_pmc0, SPRN_PA6T_PMC0);
 194 SYSFS_PMCSETUP(pa6t_pmc1, SPRN_PA6T_PMC1);
 195 SYSFS_PMCSETUP(pa6t_pmc2, SPRN_PA6T_PMC2);
 196 SYSFS_PMCSETUP(pa6t_pmc3, SPRN_PA6T_PMC3);
 197 SYSFS_PMCSETUP(pa6t_pmc4, SPRN_PA6T_PMC4);
 198 SYSFS_PMCSETUP(pa6t_pmc5, SPRN_PA6T_PMC5);
 199
 200
 201 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 202 static SYSDEV_ATTR(spurr, 0600, show_spurr, NULL);
 203 static SYSDEV_ATTR(dscr, 0600, show_dscr, store_dscr);
 204 static SYSDEV_ATTR(purr, 0600, show_purr, store_purr);
 205
 206 static struct sysdev_attribute ibm_common_attrs[] = {
 207         _SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
 208         _SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
 209 };
 210
 211 static struct sysdev_attribute ibm_pmc_attrs[] = {
 212         _SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1),
 213         _SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2),
 214         _SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3),
 215         _SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4),
 216         _SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5),
 217         _SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6),
 218         _SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7),
 219         _SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8),
 220 };
 221
 222 static struct sysdev_attribute pa6t_attrs[] = {
 223         _SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0),
 224         _SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1),
 225         _SYSDEV_ATTR(pmc0, 0600, show_pa6t_pmc0, store_pa6t_pmc0),
 226         _SYSDEV_ATTR(pmc1, 0600, show_pa6t_pmc1, store_pa6t_pmc1),
 227         _SYSDEV_ATTR(pmc2, 0600, show_pa6t_pmc2, store_pa6t_pmc2),
 228         _SYSDEV_ATTR(pmc3, 0600, show_pa6t_pmc3, store_pa6t_pmc3),
 229         _SYSDEV_ATTR(pmc4, 0600, show_pa6t_pmc4, store_pa6t_pmc4),
 230         _SYSDEV_ATTR(pmc5, 0600, show_pa6t_pmc5, store_pa6t_pmc5),
 231 };
 232
 233
 234 static void register_cpu_online(unsigned int cpu)
 235 {
 236         struct cpu *c = &per_cpu(cpu_devices, cpu);
 237         struct sys_device *s = &c->sysdev;
 238         struct sysdev_attribute *attrs, *pmc_attrs;
 239         int i, nattrs;
 240
 241         if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
 242                         cpu_has_feature(CPU_FTR_SMT))
 243                 sysdev_create_file(s, &attr_smt_snooze_delay);
 244
 245         /* PMC stuff */
 246         switch (cur_cpu_spec->pmc_type) {
 247         case PPC_PMC_IBM:
 248                 attrs = ibm_common_attrs;
 249                 nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
 250                 pmc_attrs = ibm_pmc_attrs;
 251                 break;
 252         case PPC_PMC_PA6T:
 253                 /* PA Semi starts counting at PMC0 */
 254                 attrs = pa6t_attrs;
 255                 nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
 256                 pmc_attrs = NULL;
 257                 break;
 258         default:
 259                 attrs = NULL;
 260                 nattrs = 0;
 261                 pmc_attrs = NULL;
 262         }
 263
 264         for (i = 0; i < nattrs; i++)
 265                 sysdev_create_file(s, &attrs[i]);
 266
 267         if (pmc_attrs)
 268                 for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
 269                         sysdev_create_file(s, &pmc_attrs[i]);
 270
 271         if (cpu_has_feature(CPU_FTR_MMCRA))
 272                 sysdev_create_file(s, &attr_mmcra);
 273
 274         if (cpu_has_feature(CPU_FTR_PURR))
 275                 sysdev_create_file(s, &attr_purr);
 276
 277         if (cpu_has_feature(CPU_FTR_SPURR))
 278                 sysdev_create_file(s, &attr_spurr);
 279
 280         if (cpu_has_feature(CPU_FTR_DSCR))
 281                 sysdev_create_file(s, &attr_dscr);
 282 }
 283
 284 #ifdef CONFIG_HOTPLUG_CPU
 285 static void unregister_cpu_online(unsigned int cpu)
 286 {
 287         struct cpu *c = &per_cpu(cpu_devices, cpu);
 288         struct sys_device *s = &c->sysdev;
 289         struct sysdev_attribute *attrs, *pmc_attrs;
 290         int i, nattrs;
 291
 292         BUG_ON(!c->hotpluggable);
 293
 294         if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
 295                         cpu_has_feature(CPU_FTR_SMT))
 296                 sysdev_remove_file(s, &attr_smt_snooze_delay);
 297
 298         /* PMC stuff */
 299         switch (cur_cpu_spec->pmc_type) {
 300         case PPC_PMC_IBM:
 301                 attrs = ibm_common_attrs;
 302                 nattrs = sizeof(ibm_common_attrs) / sizeof(struct sysdev_attribute);
 303                 pmc_attrs = ibm_pmc_attrs;
 304                 break;
 305         case PPC_PMC_PA6T:
 306                 /* PA Semi starts counting at PMC0 */
 307                 attrs = pa6t_attrs;
 308                 nattrs = sizeof(pa6t_attrs) / sizeof(struct sysdev_attribute);
 309                 pmc_attrs = NULL;
 310                 break;
 311         default:
 312                 attrs = NULL;
 313                 nattrs = 0;
 314                 pmc_attrs = NULL;
 315         }
 316
 317         for (i = 0; i < nattrs; i++)
 318                 sysdev_remove_file(s, &attrs[i]);
 319
 320         if (pmc_attrs)
 321                 for (i = 0; i < cur_cpu_spec->num_pmcs; i++)
 322                         sysdev_remove_file(s, &pmc_attrs[i]);
 323
 324         if (cpu_has_feature(CPU_FTR_MMCRA))
 325                 sysdev_remove_file(s, &attr_mmcra);
 326
 327         if (cpu_has_feature(CPU_FTR_PURR))
 328                 sysdev_remove_file(s, &attr_purr);
 329
 330         if (cpu_has_feature(CPU_FTR_SPURR))
 331                 sysdev_remove_file(s, &attr_spurr);
 332
 333         if (cpu_has_feature(CPU_FTR_DSCR))
 334                 sysdev_remove_file(s, &attr_dscr);
 335 }
 336 #endif /* CONFIG_HOTPLUG_CPU */
 337
 338 static int __cpuinit sysfs_cpu_notify(struct notifier_block *self,
 339                                       unsigned long action, void *hcpu)
 340 {
 341         unsigned int cpu = (unsigned int)(long)hcpu;
 342
 343         switch (action) {
 344         case CPU_ONLINE:
 345         case CPU_ONLINE_FROZEN:
 346                 register_cpu_online(cpu);
 347                 break;
 348 #ifdef CONFIG_HOTPLUG_CPU
 349         case CPU_DEAD:
 350         case CPU_DEAD_FROZEN:
 351                 unregister_cpu_online(cpu);
 352                 break;
 353 #endif
 354         }
 355         return NOTIFY_OK;
 356 }
 357
 358 static struct notifier_block __cpuinitdata sysfs_cpu_nb = {
 359         .notifier_call  = sysfs_cpu_notify,
 360 };
 361
 362 static DEFINE_MUTEX(cpu_mutex);
 363
 364 int cpu_add_sysdev_attr(struct sysdev_attribute *attr)
 365 {
 366         int cpu;
 367
 368         mutex_lock(&cpu_mutex);
 369
 370         for_each_possible_cpu(cpu) {
 371                 sysdev_create_file(get_cpu_sysdev(cpu), attr);
 372         }
 373
 374         mutex_unlock(&cpu_mutex);
 375         return 0;
 376 }
 377 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr);
 378
 379 int cpu_add_sysdev_attr_group(struct attribute_group *attrs)
 380 {
 381         int cpu;
 382         struct sys_device *sysdev;
 383
 384         mutex_lock(&cpu_mutex);
 385
 386         for_each_possible_cpu(cpu) {
 387                 sysdev = get_cpu_sysdev(cpu);
 388                 sysfs_create_group(&sysdev->kobj, attrs);
 389         }
 390
 391         mutex_unlock(&cpu_mutex);
 392         return 0;
 393 }
 394 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr_group);
 395
 396
 397 void cpu_remove_sysdev_attr(struct sysdev_attribute *attr)
 398 {
 399         int cpu;
 400
 401         mutex_lock(&cpu_mutex);
 402
 403         for_each_possible_cpu(cpu) {
 404                 sysdev_remove_file(get_cpu_sysdev(cpu), attr);
 405         }
 406
 407         mutex_unlock(&cpu_mutex);
 408 }
 409 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr);
 410
 411 void cpu_remove_sysdev_attr_group(struct attribute_group *attrs)
 412 {
 413         int cpu;
 414         struct sys_device *sysdev;
 415
 416         mutex_lock(&cpu_mutex);
 417
 418         for_each_possible_cpu(cpu) {
 419                 sysdev = get_cpu_sysdev(cpu);
 420                 sysfs_remove_group(&sysdev->kobj, attrs);
 421         }
 422
 423         mutex_unlock(&cpu_mutex);
 424 }
 425 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr_group);
 426
 427
 428 /* NUMA stuff */
 429
 430 #ifdef CONFIG_NUMA
 431 static void register_nodes(void)
 432 {
 433         int i;
 434
 435         for (i = 0; i < MAX_NUMNODES; i++)
 436                 register_one_node(i);
 437 }
 438
 439 int sysfs_add_device_to_node(struct sys_device *dev, int nid)
 440 {
 441         struct node *node = &node_devices[nid];
 442         return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
 443                         kobject_name(&dev->kobj));
 444 }
 445 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
 446
 447 void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
 448 {
 449         struct node *node = &node_devices[nid];
 450         sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
 451 }
 452 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
 453
 454 #else
 455 static void register_nodes(void)
 456 {
 457         return;
 458 }
 459
 460 #endif
 461
 462 /* Only valid if CPU is present. */
 463 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 464 {
 465         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 466
 467         return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
 468 }
 469 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 470
 471 static int __init topology_init(void)
 472 {
 473         int cpu;
 474
 475         register_nodes();
 476         register_cpu_notifier(&sysfs_cpu_nb);
 477
 478         for_each_possible_cpu(cpu) {
 479                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 480
 481                 /*
 482                  * For now, we just see if the system supports making
 483                  * the RTAS calls for CPU hotplug.  But, there may be a
 484                  * more comprehensive way to do this for an individual
 485                  * CPU.  For instance, the boot cpu might never be valid
 486                  * for hotplugging.
 487                  */
 488                 if (ppc_md.cpu_die)
 489                         c->hotpluggable = 1;
 490
 491                 if (cpu_online(cpu) || c->hotpluggable) {
 492                         register_cpu(c, cpu);
 493
 494                         sysdev_create_file(&c->sysdev, &attr_physical_id);
 495                 }
 496
 497                 if (cpu_online(cpu))
 498                         register_cpu_online(cpu);
 499         }
 500
 501         return 0;
 502 }
 503 subsys_initcall(topology_init);