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 = 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 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 173 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 174 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 175 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 176 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 177 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 178 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 179 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 180 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 181 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 182 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 183 SYSFS_PMCSETUP(purr, SPRN_PURR);
 184 SYSFS_PMCSETUP(spurr, SPRN_SPURR);
 185 SYSFS_PMCSETUP(dscr, SPRN_DSCR);
 186
 187 static SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0);
 188 static SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1);
 189 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 190 static SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1);
 191 static SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2);
 192 static SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3);
 193 static SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4);
 194 static SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5);
 195 static SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6);
 196 static SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7);
 197 static SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8);
 198 static SYSDEV_ATTR(purr, 0600, show_purr, NULL);
 199 static SYSDEV_ATTR(spurr, 0600, show_spurr, NULL);
 200 static SYSDEV_ATTR(dscr, 0600, show_dscr, store_dscr);
 201
 202 static void register_cpu_online(unsigned int cpu)
 203 {
 204         struct cpu *c = &per_cpu(cpu_devices, cpu);
 205         struct sys_device *s = &c->sysdev;
 206
 207         if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
 208                         cpu_has_feature(CPU_FTR_SMT))
 209                 sysdev_create_file(s, &attr_smt_snooze_delay);
 210
 211         /* PMC stuff */
 212
 213         sysdev_create_file(s, &attr_mmcr0);
 214         sysdev_create_file(s, &attr_mmcr1);
 215
 216         if (cpu_has_feature(CPU_FTR_MMCRA))
 217                 sysdev_create_file(s, &attr_mmcra);
 218
 219         if (cur_cpu_spec->num_pmcs >= 1)
 220                 sysdev_create_file(s, &attr_pmc1);
 221         if (cur_cpu_spec->num_pmcs >= 2)
 222                 sysdev_create_file(s, &attr_pmc2);
 223         if (cur_cpu_spec->num_pmcs >= 3)
 224                 sysdev_create_file(s, &attr_pmc3);
 225         if (cur_cpu_spec->num_pmcs >= 4)
 226                 sysdev_create_file(s, &attr_pmc4);
 227         if (cur_cpu_spec->num_pmcs >= 5)
 228                 sysdev_create_file(s, &attr_pmc5);
 229         if (cur_cpu_spec->num_pmcs >= 6)
 230                 sysdev_create_file(s, &attr_pmc6);
 231         if (cur_cpu_spec->num_pmcs >= 7)
 232                 sysdev_create_file(s, &attr_pmc7);
 233         if (cur_cpu_spec->num_pmcs >= 8)
 234                 sysdev_create_file(s, &attr_pmc8);
 235
 236         if (cpu_has_feature(CPU_FTR_PURR))
 237                 sysdev_create_file(s, &attr_purr);
 238
 239         if (cpu_has_feature(CPU_FTR_SPURR))
 240                 sysdev_create_file(s, &attr_spurr);
 241
 242         if (cpu_has_feature(CPU_FTR_DSCR))
 243                 sysdev_create_file(s, &attr_dscr);
 244 }
 245
 246 #ifdef CONFIG_HOTPLUG_CPU
 247 static void unregister_cpu_online(unsigned int cpu)
 248 {
 249         struct cpu *c = &per_cpu(cpu_devices, cpu);
 250         struct sys_device *s = &c->sysdev;
 251
 252         BUG_ON(!c->hotpluggable);
 253
 254         if (!firmware_has_feature(FW_FEATURE_ISERIES) &&
 255                         cpu_has_feature(CPU_FTR_SMT))
 256                 sysdev_remove_file(s, &attr_smt_snooze_delay);
 257
 258         /* PMC stuff */
 259
 260         sysdev_remove_file(s, &attr_mmcr0);
 261         sysdev_remove_file(s, &attr_mmcr1);
 262
 263         if (cpu_has_feature(CPU_FTR_MMCRA))
 264                 sysdev_remove_file(s, &attr_mmcra);
 265
 266         if (cur_cpu_spec->num_pmcs >= 1)
 267                 sysdev_remove_file(s, &attr_pmc1);
 268         if (cur_cpu_spec->num_pmcs >= 2)
 269                 sysdev_remove_file(s, &attr_pmc2);
 270         if (cur_cpu_spec->num_pmcs >= 3)
 271                 sysdev_remove_file(s, &attr_pmc3);
 272         if (cur_cpu_spec->num_pmcs >= 4)
 273                 sysdev_remove_file(s, &attr_pmc4);
 274         if (cur_cpu_spec->num_pmcs >= 5)
 275                 sysdev_remove_file(s, &attr_pmc5);
 276         if (cur_cpu_spec->num_pmcs >= 6)
 277                 sysdev_remove_file(s, &attr_pmc6);
 278         if (cur_cpu_spec->num_pmcs >= 7)
 279                 sysdev_remove_file(s, &attr_pmc7);
 280         if (cur_cpu_spec->num_pmcs >= 8)
 281                 sysdev_remove_file(s, &attr_pmc8);
 282
 283         if (cpu_has_feature(CPU_FTR_PURR))
 284                 sysdev_remove_file(s, &attr_purr);
 285
 286         if (cpu_has_feature(CPU_FTR_SPURR))
 287                 sysdev_remove_file(s, &attr_spurr);
 288
 289         if (cpu_has_feature(CPU_FTR_DSCR))
 290                 sysdev_remove_file(s, &attr_dscr);
 291 }
 292 #endif /* CONFIG_HOTPLUG_CPU */
 293
 294 static int __cpuinit sysfs_cpu_notify(struct notifier_block *self,
 295                                       unsigned long action, void *hcpu)
 296 {
 297         unsigned int cpu = (unsigned int)(long)hcpu;
 298
 299         switch (action) {
 300         case CPU_ONLINE:
 301                 register_cpu_online(cpu);
 302                 break;
 303 #ifdef CONFIG_HOTPLUG_CPU
 304         case CPU_DEAD:
 305                 unregister_cpu_online(cpu);
 306                 break;
 307 #endif
 308         }
 309         return NOTIFY_OK;
 310 }
 311
 312 static struct notifier_block __cpuinitdata sysfs_cpu_nb = {
 313         .notifier_call  = sysfs_cpu_notify,
 314 };
 315
 316 static DEFINE_MUTEX(cpu_mutex);
 317
 318 int cpu_add_sysdev_attr(struct sysdev_attribute *attr)
 319 {
 320         int cpu;
 321
 322         mutex_lock(&cpu_mutex);
 323
 324         for_each_possible_cpu(cpu) {
 325                 sysdev_create_file(get_cpu_sysdev(cpu), attr);
 326         }
 327
 328         mutex_unlock(&cpu_mutex);
 329         return 0;
 330 }
 331 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr);
 332
 333 int cpu_add_sysdev_attr_group(struct attribute_group *attrs)
 334 {
 335         int cpu;
 336         struct sys_device *sysdev;
 337
 338         mutex_lock(&cpu_mutex);
 339
 340         for_each_possible_cpu(cpu) {
 341                 sysdev = get_cpu_sysdev(cpu);
 342                 sysfs_create_group(&sysdev->kobj, attrs);
 343         }
 344
 345         mutex_unlock(&cpu_mutex);
 346         return 0;
 347 }
 348 EXPORT_SYMBOL_GPL(cpu_add_sysdev_attr_group);
 349
 350
 351 void cpu_remove_sysdev_attr(struct sysdev_attribute *attr)
 352 {
 353         int cpu;
 354
 355         mutex_lock(&cpu_mutex);
 356
 357         for_each_possible_cpu(cpu) {
 358                 sysdev_remove_file(get_cpu_sysdev(cpu), attr);
 359         }
 360
 361         mutex_unlock(&cpu_mutex);
 362 }
 363 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr);
 364
 365 void cpu_remove_sysdev_attr_group(struct attribute_group *attrs)
 366 {
 367         int cpu;
 368         struct sys_device *sysdev;
 369
 370         mutex_lock(&cpu_mutex);
 371
 372         for_each_possible_cpu(cpu) {
 373                 sysdev = get_cpu_sysdev(cpu);
 374                 sysfs_remove_group(&sysdev->kobj, attrs);
 375         }
 376
 377         mutex_unlock(&cpu_mutex);
 378 }
 379 EXPORT_SYMBOL_GPL(cpu_remove_sysdev_attr_group);
 380
 381
 382 /* NUMA stuff */
 383
 384 #ifdef CONFIG_NUMA
 385 static void register_nodes(void)
 386 {
 387         int i;
 388
 389         for (i = 0; i < MAX_NUMNODES; i++)
 390                 register_one_node(i);
 391 }
 392
 393 int sysfs_add_device_to_node(struct sys_device *dev, int nid)
 394 {
 395         struct node *node = &node_devices[nid];
 396         return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
 397                         kobject_name(&dev->kobj));
 398 }
 399
 400 void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
 401 {
 402         struct node *node = &node_devices[nid];
 403         sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
 404 }
 405
 406 #else
 407 static void register_nodes(void)
 408 {
 409         return;
 410 }
 411
 412 #endif
 413
 414 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
 415 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
 416
 417 /* Only valid if CPU is present. */
 418 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 419 {
 420         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 421
 422         return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
 423 }
 424 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 425
 426 static int __init topology_init(void)
 427 {
 428         int cpu;
 429
 430         register_nodes();
 431         register_cpu_notifier(&sysfs_cpu_nb);
 432
 433         for_each_possible_cpu(cpu) {
 434                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 435
 436                 /*
 437                  * For now, we just see if the system supports making
 438                  * the RTAS calls for CPU hotplug.  But, there may be a
 439                  * more comprehensive way to do this for an individual
 440                  * CPU.  For instance, the boot cpu might never be valid
 441                  * for hotplugging.
 442                  */
 443                 if (ppc_md.cpu_die)
 444                         c->hotpluggable = 1;
 445
 446                 if (cpu_online(cpu) || c->hotpluggable) {
 447                         register_cpu(c, cpu);
 448
 449                         sysdev_create_file(&c->sysdev, &attr_physical_id);
 450                 }
 451
 452                 if (cpu_online(cpu))
 453                         register_cpu_online(cpu);
 454         }
 455
 456         return 0;
 457 }
 458 __initcall(topology_init);