arch/powerpc/kernel/sysfs.c

   1 #include <linux/config.h>
   2 #include <linux/sysdev.h>
   3 #include <linux/cpu.h>
   4 #include <linux/smp.h>
   5 #include <linux/percpu.h>
   6 #include <linux/init.h>
   7 #include <linux/sched.h>
   8 #include <linux/module.h>
   9 #include <linux/nodemask.h>
  10 #include <linux/cpumask.h>
  11 #include <linux/notifier.h>
  12
  13 #include <asm/current.h>
  14 #include <asm/processor.h>
  15 #include <asm/cputable.h>
  16 #include <asm/firmware.h>
  17 #include <asm/hvcall.h>
  18 #include <asm/prom.h>
  19 #include <asm/paca.h>
  20 #include <asm/lppaca.h>
  21 #include <asm/machdep.h>
  22 #include <asm/smp.h>
  23
  24 static DEFINE_PER_CPU(struct cpu, cpu_devices);
  25
  26 /* SMT stuff */
  27
  28 #ifdef CONFIG_PPC_MULTIPLATFORM
  29 /* default to snooze disabled */
  30 DEFINE_PER_CPU(unsigned long, smt_snooze_delay);
  31
  32 static ssize_t store_smt_snooze_delay(struct sys_device *dev, const char *buf,
  33                                       size_t count)
  34 {
  35         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
  36         ssize_t ret;
  37         unsigned long snooze;
  38
  39         ret = sscanf(buf, "%lu", &snooze);
  40         if (ret != 1)
  41                 return -EINVAL;
  42
  43         per_cpu(smt_snooze_delay, cpu->sysdev.id) = snooze;
  44
  45         return count;
  46 }
  47
  48 static ssize_t show_smt_snooze_delay(struct sys_device *dev, char *buf)
  49 {
  50         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
  51
  52         return sprintf(buf, "%lu\n", per_cpu(smt_snooze_delay, cpu->sysdev.id));
  53 }
  54
  55 static SYSDEV_ATTR(smt_snooze_delay, 0644, show_smt_snooze_delay,
  56                    store_smt_snooze_delay);
  57
  58 /* Only parse OF options if the matching cmdline option was not specified */
  59 static int smt_snooze_cmdline;
  60
  61 static int __init smt_setup(void)
  62 {
  63         struct device_node *options;
  64         unsigned int *val;
  65         unsigned int cpu;
  66
  67         if (!cpu_has_feature(CPU_FTR_SMT))
  68                 return -ENODEV;
  69
  70         options = find_path_device("/options");
  71         if (!options)
  72                 return -ENODEV;
  73
  74         val = (unsigned int *)get_property(options, "ibm,smt-snooze-delay",
  75                                            NULL);
  76         if (!smt_snooze_cmdline && val) {
  77                 for_each_possible_cpu(cpu)
  78                         per_cpu(smt_snooze_delay, cpu) = *val;
  79         }
  80
  81         return 0;
  82 }
  83 __initcall(smt_setup);
  84
  85 static int __init setup_smt_snooze_delay(char *str)
  86 {
  87         unsigned int cpu;
  88         int snooze;
  89
  90         if (!cpu_has_feature(CPU_FTR_SMT))
  91                 return 1;
  92
  93         smt_snooze_cmdline = 1;
  94
  95         if (get_option(&str, &snooze)) {
  96                 for_each_possible_cpu(cpu)
  97                         per_cpu(smt_snooze_delay, cpu) = snooze;
  98         }
  99
 100         return 1;
 101 }
 102 __setup("smt-snooze-delay=", setup_smt_snooze_delay);
 103
 104 #endif /* CONFIG_PPC_MULTIPLATFORM */
 105
 106 /*
 107  * Enabling PMCs will slow partition context switch times so we only do
 108  * it the first time we write to the PMCs.
 109  */
 110
 111 static DEFINE_PER_CPU(char, pmcs_enabled);
 112
 113 void ppc64_enable_pmcs(void)
 114 {
 115         /* Only need to enable them once */
 116         if (__get_cpu_var(pmcs_enabled))
 117                 return;
 118
 119         __get_cpu_var(pmcs_enabled) = 1;
 120
 121         if (ppc_md.enable_pmcs)
 122                 ppc_md.enable_pmcs();
 123 }
 124 EXPORT_SYMBOL(ppc64_enable_pmcs);
 125
 126 /* XXX convert to rusty's on_one_cpu */
 127 static unsigned long run_on_cpu(unsigned long cpu,
 128                                 unsigned long (*func)(unsigned long),
 129                                 unsigned long arg)
 130 {
 131         cpumask_t old_affinity = current->cpus_allowed;
 132         unsigned long ret;
 133
 134         /* should return -EINVAL to userspace */
 135         if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
 136                 return 0;
 137
 138         ret = func(arg);
 139
 140         set_cpus_allowed(current, old_affinity);
 141
 142         return ret;
 143 }
 144
 145 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
 146 static unsigned long read_##NAME(unsigned long junk) \
 147 { \
 148         return mfspr(ADDRESS); \
 149 } \
 150 static unsigned long write_##NAME(unsigned long val) \
 151 { \
 152         ppc64_enable_pmcs(); \
 153         mtspr(ADDRESS, val); \
 154         return 0; \
 155 } \
 156 static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
 157 { \
 158         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 159         unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
 160         return sprintf(buf, "%lx\n", val); \
 161 } \
 162 static ssize_t __attribute_used__ \
 163         store_##NAME(struct sys_device *dev, const char *buf, size_t count) \
 164 { \
 165         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 166         unsigned long val; \
 167         int ret = sscanf(buf, "%lx", &val); \
 168         if (ret != 1) \
 169                 return -EINVAL; \
 170         run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
 171         return count; \
 172 }
 173
 174 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 175 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 176 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 177 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 178 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 179 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 180 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 181 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 182 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 183 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 184 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 185 SYSFS_PMCSETUP(purr, SPRN_PURR);
 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
 200 static void register_cpu_online(unsigned int cpu)
 201 {
 202         struct cpu *c = &per_cpu(cpu_devices, cpu);
 203         struct sys_device *s = &c->sysdev;
 204
 205 #ifndef CONFIG_PPC_ISERIES
 206         if (cpu_has_feature(CPU_FTR_SMT))
 207                 sysdev_create_file(s, &attr_smt_snooze_delay);
 208 #endif
 209
 210         /* PMC stuff */
 211
 212         sysdev_create_file(s, &attr_mmcr0);
 213         sysdev_create_file(s, &attr_mmcr1);
 214
 215         if (cpu_has_feature(CPU_FTR_MMCRA))
 216                 sysdev_create_file(s, &attr_mmcra);
 217
 218         if (cur_cpu_spec->num_pmcs >= 1)
 219                 sysdev_create_file(s, &attr_pmc1);
 220         if (cur_cpu_spec->num_pmcs >= 2)
 221                 sysdev_create_file(s, &attr_pmc2);
 222         if (cur_cpu_spec->num_pmcs >= 3)
 223                 sysdev_create_file(s, &attr_pmc3);
 224         if (cur_cpu_spec->num_pmcs >= 4)
 225                 sysdev_create_file(s, &attr_pmc4);
 226         if (cur_cpu_spec->num_pmcs >= 5)
 227                 sysdev_create_file(s, &attr_pmc5);
 228         if (cur_cpu_spec->num_pmcs >= 6)
 229                 sysdev_create_file(s, &attr_pmc6);
 230         if (cur_cpu_spec->num_pmcs >= 7)
 231                 sysdev_create_file(s, &attr_pmc7);
 232         if (cur_cpu_spec->num_pmcs >= 8)
 233                 sysdev_create_file(s, &attr_pmc8);
 234
 235         if (cpu_has_feature(CPU_FTR_SMT))
 236                 sysdev_create_file(s, &attr_purr);
 237 }
 238
 239 #ifdef CONFIG_HOTPLUG_CPU
 240 static void unregister_cpu_online(unsigned int cpu)
 241 {
 242         struct cpu *c = &per_cpu(cpu_devices, cpu);
 243         struct sys_device *s = &c->sysdev;
 244
 245         BUG_ON(c->no_control);
 246
 247 #ifndef CONFIG_PPC_ISERIES
 248         if (cpu_has_feature(CPU_FTR_SMT))
 249                 sysdev_remove_file(s, &attr_smt_snooze_delay);
 250 #endif
 251
 252         /* PMC stuff */
 253
 254         sysdev_remove_file(s, &attr_mmcr0);
 255         sysdev_remove_file(s, &attr_mmcr1);
 256
 257         if (cpu_has_feature(CPU_FTR_MMCRA))
 258                 sysdev_remove_file(s, &attr_mmcra);
 259
 260         if (cur_cpu_spec->num_pmcs >= 1)
 261                 sysdev_remove_file(s, &attr_pmc1);
 262         if (cur_cpu_spec->num_pmcs >= 2)
 263                 sysdev_remove_file(s, &attr_pmc2);
 264         if (cur_cpu_spec->num_pmcs >= 3)
 265                 sysdev_remove_file(s, &attr_pmc3);
 266         if (cur_cpu_spec->num_pmcs >= 4)
 267                 sysdev_remove_file(s, &attr_pmc4);
 268         if (cur_cpu_spec->num_pmcs >= 5)
 269                 sysdev_remove_file(s, &attr_pmc5);
 270         if (cur_cpu_spec->num_pmcs >= 6)
 271                 sysdev_remove_file(s, &attr_pmc6);
 272         if (cur_cpu_spec->num_pmcs >= 7)
 273                 sysdev_remove_file(s, &attr_pmc7);
 274         if (cur_cpu_spec->num_pmcs >= 8)
 275                 sysdev_remove_file(s, &attr_pmc8);
 276
 277         if (cpu_has_feature(CPU_FTR_SMT))
 278                 sysdev_remove_file(s, &attr_purr);
 279 }
 280 #endif /* CONFIG_HOTPLUG_CPU */
 281
 282 static int sysfs_cpu_notify(struct notifier_block *self,
 283                                       unsigned long action, void *hcpu)
 284 {
 285         unsigned int cpu = (unsigned int)(long)hcpu;
 286
 287         switch (action) {
 288         case CPU_ONLINE:
 289                 register_cpu_online(cpu);
 290                 break;
 291 #ifdef CONFIG_HOTPLUG_CPU
 292         case CPU_DEAD:
 293                 unregister_cpu_online(cpu);
 294                 break;
 295 #endif
 296         }
 297         return NOTIFY_OK;
 298 }
 299
 300 static struct notifier_block sysfs_cpu_nb = {
 301         .notifier_call  = sysfs_cpu_notify,
 302 };
 303
 304 /* NUMA stuff */
 305
 306 #ifdef CONFIG_NUMA
 307 static struct node node_devices[MAX_NUMNODES];
 308
 309 static void register_nodes(void)
 310 {
 311         int i;
 312
 313         for (i = 0; i < MAX_NUMNODES; i++) {
 314                 if (node_online(i)) {
 315                         int p_node = parent_node(i);
 316                         struct node *parent = NULL;
 317
 318                         if (p_node != i)
 319                                 parent = &node_devices[p_node];
 320
 321                         register_node(&node_devices[i], i, parent);
 322                 }
 323         }
 324 }
 325
 326 int sysfs_add_device_to_node(struct sys_device *dev, int nid)
 327 {
 328         struct node *node = &node_devices[nid];
 329         return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
 330                         kobject_name(&dev->kobj));
 331 }
 332
 333 void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
 334 {
 335         struct node *node = &node_devices[nid];
 336         sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
 337 }
 338
 339 #else
 340 static void register_nodes(void)
 341 {
 342         return;
 343 }
 344
 345 #endif
 346
 347 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
 348 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
 349
 350 /* Only valid if CPU is present. */
 351 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 352 {
 353         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 354
 355         return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
 356 }
 357 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 358
 359 static int __init topology_init(void)
 360 {
 361         int cpu;
 362         struct node *parent = NULL;
 363
 364         register_nodes();
 365
 366         register_cpu_notifier(&sysfs_cpu_nb);
 367
 368         for_each_possible_cpu(cpu) {
 369                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 370
 371 #ifdef CONFIG_NUMA
 372                 /* The node to which a cpu belongs can't be known
 373                  * until the cpu is made present.
 374                  */
 375                 parent = NULL;
 376                 if (cpu_present(cpu))
 377                         parent = &node_devices[cpu_to_node(cpu)];
 378 #endif
 379                 /*
 380                  * For now, we just see if the system supports making
 381                  * the RTAS calls for CPU hotplug.  But, there may be a
 382                  * more comprehensive way to do this for an individual
 383                  * CPU.  For instance, the boot cpu might never be valid
 384                  * for hotplugging.
 385                  */
 386                 if (!ppc_md.cpu_die)
 387                         c->no_control = 1;
 388
 389                 if (cpu_online(cpu) || (c->no_control == 0)) {
 390                         register_cpu(c, cpu, parent);
 391
 392                         sysdev_create_file(&c->sysdev, &attr_physical_id);
 393                 }
 394
 395                 if (cpu_online(cpu))
 396                         register_cpu_online(cpu);
 397         }
 398
 399         return 0;
 400 }
 401 __initcall(topology_init);