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         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 = (unsigned int *)get_property(options, "ibm,smt-snooze-delay",
  74                                            NULL);
  75         if (!smt_snooze_cmdline && val) {
  76                 for_each_possible_cpu(cpu)
  77                         per_cpu(smt_snooze_delay, cpu) = *val;
  78         }
  79
  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 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 174 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 175 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 176 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 177 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 178 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 179 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 180 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 181 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 182 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 183 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 184 SYSFS_PMCSETUP(purr, SPRN_PURR);
 185
 186 static SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0);
 187 static SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1);
 188 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 189 static SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1);
 190 static SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2);
 191 static SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3);
 192 static SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4);
 193 static SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5);
 194 static SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6);
 195 static SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7);
 196 static SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8);
 197 static SYSDEV_ATTR(purr, 0600, show_purr, NULL);
 198
 199 static void register_cpu_online(unsigned int cpu)
 200 {
 201         struct cpu *c = &per_cpu(cpu_devices, cpu);
 202         struct sys_device *s = &c->sysdev;
 203
 204 #ifndef CONFIG_PPC_ISERIES
 205         if (cpu_has_feature(CPU_FTR_SMT))
 206                 sysdev_create_file(s, &attr_smt_snooze_delay);
 207 #endif
 208
 209         /* PMC stuff */
 210
 211         sysdev_create_file(s, &attr_mmcr0);
 212         sysdev_create_file(s, &attr_mmcr1);
 213
 214         if (cpu_has_feature(CPU_FTR_MMCRA))
 215                 sysdev_create_file(s, &attr_mmcra);
 216
 217         if (cur_cpu_spec->num_pmcs >= 1)
 218                 sysdev_create_file(s, &attr_pmc1);
 219         if (cur_cpu_spec->num_pmcs >= 2)
 220                 sysdev_create_file(s, &attr_pmc2);
 221         if (cur_cpu_spec->num_pmcs >= 3)
 222                 sysdev_create_file(s, &attr_pmc3);
 223         if (cur_cpu_spec->num_pmcs >= 4)
 224                 sysdev_create_file(s, &attr_pmc4);
 225         if (cur_cpu_spec->num_pmcs >= 5)
 226                 sysdev_create_file(s, &attr_pmc5);
 227         if (cur_cpu_spec->num_pmcs >= 6)
 228                 sysdev_create_file(s, &attr_pmc6);
 229         if (cur_cpu_spec->num_pmcs >= 7)
 230                 sysdev_create_file(s, &attr_pmc7);
 231         if (cur_cpu_spec->num_pmcs >= 8)
 232                 sysdev_create_file(s, &attr_pmc8);
 233
 234         if (cpu_has_feature(CPU_FTR_SMT))
 235                 sysdev_create_file(s, &attr_purr);
 236 }
 237
 238 #ifdef CONFIG_HOTPLUG_CPU
 239 static void unregister_cpu_online(unsigned int cpu)
 240 {
 241         struct cpu *c = &per_cpu(cpu_devices, cpu);
 242         struct sys_device *s = &c->sysdev;
 243
 244         BUG_ON(c->no_control);
 245
 246 #ifndef CONFIG_PPC_ISERIES
 247         if (cpu_has_feature(CPU_FTR_SMT))
 248                 sysdev_remove_file(s, &attr_smt_snooze_delay);
 249 #endif
 250
 251         /* PMC stuff */
 252
 253         sysdev_remove_file(s, &attr_mmcr0);
 254         sysdev_remove_file(s, &attr_mmcr1);
 255
 256         if (cpu_has_feature(CPU_FTR_MMCRA))
 257                 sysdev_remove_file(s, &attr_mmcra);
 258
 259         if (cur_cpu_spec->num_pmcs >= 1)
 260                 sysdev_remove_file(s, &attr_pmc1);
 261         if (cur_cpu_spec->num_pmcs >= 2)
 262                 sysdev_remove_file(s, &attr_pmc2);
 263         if (cur_cpu_spec->num_pmcs >= 3)
 264                 sysdev_remove_file(s, &attr_pmc3);
 265         if (cur_cpu_spec->num_pmcs >= 4)
 266                 sysdev_remove_file(s, &attr_pmc4);
 267         if (cur_cpu_spec->num_pmcs >= 5)
 268                 sysdev_remove_file(s, &attr_pmc5);
 269         if (cur_cpu_spec->num_pmcs >= 6)
 270                 sysdev_remove_file(s, &attr_pmc6);
 271         if (cur_cpu_spec->num_pmcs >= 7)
 272                 sysdev_remove_file(s, &attr_pmc7);
 273         if (cur_cpu_spec->num_pmcs >= 8)
 274                 sysdev_remove_file(s, &attr_pmc8);
 275
 276         if (cpu_has_feature(CPU_FTR_SMT))
 277                 sysdev_remove_file(s, &attr_purr);
 278 }
 279 #endif /* CONFIG_HOTPLUG_CPU */
 280
 281 static int __cpuinit sysfs_cpu_notify(struct notifier_block *self,
 282                                       unsigned long action, void *hcpu)
 283 {
 284         unsigned int cpu = (unsigned int)(long)hcpu;
 285
 286         switch (action) {
 287         case CPU_ONLINE:
 288                 register_cpu_online(cpu);
 289                 break;
 290 #ifdef CONFIG_HOTPLUG_CPU
 291         case CPU_DEAD:
 292                 unregister_cpu_online(cpu);
 293                 break;
 294 #endif
 295         }
 296         return NOTIFY_OK;
 297 }
 298
 299 static struct notifier_block __cpuinitdata sysfs_cpu_nb = {
 300         .notifier_call  = sysfs_cpu_notify,
 301 };
 302
 303 /* NUMA stuff */
 304
 305 #ifdef CONFIG_NUMA
 306 static void register_nodes(void)
 307 {
 308         int i;
 309
 310         for (i = 0; i < MAX_NUMNODES; i++)
 311                 register_one_node(i);
 312 }
 313
 314 int sysfs_add_device_to_node(struct sys_device *dev, int nid)
 315 {
 316         struct node *node = &node_devices[nid];
 317         return sysfs_create_link(&node->sysdev.kobj, &dev->kobj,
 318                         kobject_name(&dev->kobj));
 319 }
 320
 321 void sysfs_remove_device_from_node(struct sys_device *dev, int nid)
 322 {
 323         struct node *node = &node_devices[nid];
 324         sysfs_remove_link(&node->sysdev.kobj, kobject_name(&dev->kobj));
 325 }
 326
 327 #else
 328 static void register_nodes(void)
 329 {
 330         return;
 331 }
 332
 333 #endif
 334
 335 EXPORT_SYMBOL_GPL(sysfs_add_device_to_node);
 336 EXPORT_SYMBOL_GPL(sysfs_remove_device_from_node);
 337
 338 /* Only valid if CPU is present. */
 339 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 340 {
 341         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 342
 343         return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
 344 }
 345 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 346
 347 static int __init topology_init(void)
 348 {
 349         int cpu;
 350
 351         register_nodes();
 352         register_cpu_notifier(&sysfs_cpu_nb);
 353
 354         for_each_possible_cpu(cpu) {
 355                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 356
 357                 /*
 358                  * For now, we just see if the system supports making
 359                  * the RTAS calls for CPU hotplug.  But, there may be a
 360                  * more comprehensive way to do this for an individual
 361                  * CPU.  For instance, the boot cpu might never be valid
 362                  * for hotplugging.
 363                  */
 364                 if (!ppc_md.cpu_die)
 365                         c->no_control = 1;
 366
 367                 if (cpu_online(cpu) || (c->no_control == 0)) {
 368                         register_cpu(c, cpu);
 369
 370                         sysdev_create_file(&c->sysdev, &attr_physical_id);
 371                 }
 372
 373                 if (cpu_online(cpu))
 374                         register_cpu_online(cpu);
 375         }
 376
 377         return 0;
 378 }
 379 __initcall(topology_init);