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 /* default to snooze disabled */
  29 DEFINE_PER_CPU(unsigned long, smt_snooze_delay);
  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
 185 static SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0);
 186 static SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1);
 187 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 188 static SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1);
 189 static SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2);
 190 static SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3);
 191 static SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4);
 192 static SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5);
 193 static SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6);
 194 static SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7);
 195 static SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8);
 196 static SYSDEV_ATTR(purr, 0600, show_purr, NULL);
 197
 198 static void register_cpu_online(unsigned int cpu)
 199 {
 200         struct cpu *c = &per_cpu(cpu_devices, cpu);
 201         struct sys_device *s = &c->sysdev;
 202
 203 #ifndef CONFIG_PPC_ISERIES
 204         if (cpu_has_feature(CPU_FTR_SMT))
 205                 sysdev_create_file(s, &attr_smt_snooze_delay);
 206 #endif
 207
 208         /* PMC stuff */
 209
 210         sysdev_create_file(s, &attr_mmcr0);
 211         sysdev_create_file(s, &attr_mmcr1);
 212
 213         if (cpu_has_feature(CPU_FTR_MMCRA))
 214                 sysdev_create_file(s, &attr_mmcra);
 215
 216         if (cur_cpu_spec->num_pmcs >= 1)
 217                 sysdev_create_file(s, &attr_pmc1);
 218         if (cur_cpu_spec->num_pmcs >= 2)
 219                 sysdev_create_file(s, &attr_pmc2);
 220         if (cur_cpu_spec->num_pmcs >= 3)
 221                 sysdev_create_file(s, &attr_pmc3);
 222         if (cur_cpu_spec->num_pmcs >= 4)
 223                 sysdev_create_file(s, &attr_pmc4);
 224         if (cur_cpu_spec->num_pmcs >= 5)
 225                 sysdev_create_file(s, &attr_pmc5);
 226         if (cur_cpu_spec->num_pmcs >= 6)
 227                 sysdev_create_file(s, &attr_pmc6);
 228         if (cur_cpu_spec->num_pmcs >= 7)
 229                 sysdev_create_file(s, &attr_pmc7);
 230         if (cur_cpu_spec->num_pmcs >= 8)
 231                 sysdev_create_file(s, &attr_pmc8);
 232
 233         if (cpu_has_feature(CPU_FTR_PURR))
 234                 sysdev_create_file(s, &attr_purr);
 235 }
 236
 237 #ifdef CONFIG_HOTPLUG_CPU
 238 static void unregister_cpu_online(unsigned int cpu)
 239 {
 240         struct cpu *c = &per_cpu(cpu_devices, cpu);
 241         struct sys_device *s = &c->sysdev;
 242
 243         BUG_ON(c->no_control);
 244
 245 #ifndef CONFIG_PPC_ISERIES
 246         if (cpu_has_feature(CPU_FTR_SMT))
 247                 sysdev_remove_file(s, &attr_smt_snooze_delay);
 248 #endif
 249
 250         /* PMC stuff */
 251
 252         sysdev_remove_file(s, &attr_mmcr0);
 253         sysdev_remove_file(s, &attr_mmcr1);
 254
 255         if (cpu_has_feature(CPU_FTR_MMCRA))
 256                 sysdev_remove_file(s, &attr_mmcra);
 257
 258         if (cur_cpu_spec->num_pmcs >= 1)
 259                 sysdev_remove_file(s, &attr_pmc1);
 260         if (cur_cpu_spec->num_pmcs >= 2)
 261                 sysdev_remove_file(s, &attr_pmc2);
 262         if (cur_cpu_spec->num_pmcs >= 3)
 263                 sysdev_remove_file(s, &attr_pmc3);
 264         if (cur_cpu_spec->num_pmcs >= 4)
 265                 sysdev_remove_file(s, &attr_pmc4);
 266         if (cur_cpu_spec->num_pmcs >= 5)
 267                 sysdev_remove_file(s, &attr_pmc5);
 268         if (cur_cpu_spec->num_pmcs >= 6)
 269                 sysdev_remove_file(s, &attr_pmc6);
 270         if (cur_cpu_spec->num_pmcs >= 7)
 271                 sysdev_remove_file(s, &attr_pmc7);
 272         if (cur_cpu_spec->num_pmcs >= 8)
 273                 sysdev_remove_file(s, &attr_pmc8);
 274
 275         if (cpu_has_feature(CPU_FTR_PURR))
 276                 sysdev_remove_file(s, &attr_purr);
 277 }
 278 #endif /* CONFIG_HOTPLUG_CPU */
 279
 280 static int __cpuinit sysfs_cpu_notify(struct notifier_block *self,
 281                                       unsigned long action, void *hcpu)
 282 {
 283         unsigned int cpu = (unsigned int)(long)hcpu;
 284
 285         switch (action) {
 286         case CPU_ONLINE:
 287                 register_cpu_online(cpu);
 288                 break;
 289 #ifdef CONFIG_HOTPLUG_CPU
 290         case CPU_DEAD:
 291                 unregister_cpu_online(cpu);
 292                 break;
 293 #endif
 294         }
 295         return NOTIFY_OK;
 296 }
 297
 298 static struct notifier_block __cpuinitdata sysfs_cpu_nb = {
 299         .notifier_call  = sysfs_cpu_notify,
 300 };
 301
 302 /* NUMA stuff */
 303
 304 #ifdef CONFIG_NUMA
 305 static void register_nodes(void)
 306 {
 307         int i;
 308
 309         for (i = 0; i < MAX_NUMNODES; i++)
 310                 register_one_node(i);
 311 }
 312
 313 int sysfs_add_device_to_node(struct sys_device *dev, int nid)
 314 {
 315         struct node *node = &node_devices[nid];
 316         return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
 317                         kobject_name(&dev->kobj));
 318 }
 319
 320 void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
 321 {
 322         struct node *node = &node_devices[nid];
 323         sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
 324 }
 325
 326 #else
 327 static void register_nodes(void)
 328 {
 329         return;
 330 }
 331
 332 #endif
 333
 334 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
 335 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
 336
 337 /* Only valid if CPU is present. */
 338 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 339 {
 340         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 341
 342         return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
 343 }
 344 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 345
 346 static int __init topology_init(void)
 347 {
 348         int cpu;
 349
 350         register_nodes();
 351         register_cpu_notifier(&sysfs_cpu_nb);
 352
 353         for_each_possible_cpu(cpu) {
 354                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 355
 356                 /*
 357                  * For now, we just see if the system supports making
 358                  * the RTAS calls for CPU hotplug.  But, there may be a
 359                  * more comprehensive way to do this for an individual
 360                  * CPU.  For instance, the boot cpu might never be valid
 361                  * for hotplugging.
 362                  */
 363                 if (!ppc_md.cpu_die)
 364                         c->no_control = 1;
 365
 366                 if (cpu_online(cpu) || (c->no_control == 0)) {
 367                         register_cpu(c, cpu);
 368
 369                         sysdev_create_file(&c->sysdev, &attr_physical_id);
 370                 }
 371
 372                 if (cpu_online(cpu))
 373                         register_cpu_online(cpu);
 374         }
 375
 376         return 0;
 377 }
 378 __initcall(topology_init);