arch/ppc64/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/hvcall.h>
  17 #include <asm/prom.h>
  18 #include <asm/systemcfg.h>
  19 #include <asm/paca.h>
  20 #include <asm/lppaca.h>
  21 #include <asm/machdep.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 1;
  68
  69         options = find_path_device("/options");
  70         if (!options)
  71                 return 1;
  72
  73         val = (unsigned int *)get_property(options, "ibm,smt-snooze-delay",
  74                                            NULL);
  75         if (!smt_snooze_cmdline && val) {
  76                 for_each_cpu(cpu)
  77                         per_cpu(smt_snooze_delay, cpu) = *val;
  78         }
  79
  80         return 1;
  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_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 /*
 104  * Enabling PMCs will slow partition context switch times so we only do
 105  * it the first time we write to the PMCs.
 106  */
 107
 108 static DEFINE_PER_CPU(char, pmcs_enabled);
 109
 110 void ppc64_enable_pmcs(void)
 111 {
 112         unsigned long hid0;
 113 #ifdef CONFIG_PPC_PSERIES
 114         unsigned long set, reset;
 115         int ret;
 116         unsigned int ctrl;
 117 #endif /* CONFIG_PPC_PSERIES */
 118
 119         /* Only need to enable them once */
 120         if (__get_cpu_var(pmcs_enabled))
 121                 return;
 122
 123         __get_cpu_var(pmcs_enabled) = 1;
 124
 125         switch (systemcfg->platform) {
 126         case PLATFORM_PSERIES:
 127         case PLATFORM_POWERMAC:
 128                 hid0 = mfspr(HID0);
 129                 hid0 |= 1UL << (63 - 20);
 130
 131                 /* POWER4 requires the following sequence */
 132                 asm volatile(
 133                              "sync\n"
 134                              "mtspr     %1, %0\n"
 135                              "mfspr     %0, %1\n"
 136                              "mfspr     %0, %1\n"
 137                              "mfspr     %0, %1\n"
 138                              "mfspr     %0, %1\n"
 139                              "mfspr     %0, %1\n"
 140                              "mfspr     %0, %1\n"
 141                              "isync" : "=&r" (hid0) : "i" (HID0), "0" (hid0):
 142                              "memory");
 143                 break;
 144
 145 #ifdef CONFIG_PPC_PSERIES
 146         case PLATFORM_PSERIES_LPAR:
 147                 set = 1UL << 63;
 148                 reset = 0;
 149                 ret = plpar_hcall_norets(H_PERFMON, set, reset);
 150                 if (ret)
 151                         printk(KERN_ERR "H_PERFMON call on cpu %u "
 152                                "returned %d\n",
 153                                smp_processor_id(), ret);
 154                 break;
 155 #endif /* CONFIG_PPC_PSERIES */
 156
 157         default:
 158                 break;
 159         }
 160
 161 #ifdef CONFIG_PPC_PSERIES
 162         /* instruct hypervisor to maintain PMCs */
 163         if (cur_cpu_spec->firmware_features & FW_FEATURE_SPLPAR)
 164                 get_paca()->lppaca.pmcregs_in_use = 1;
 165
 166         /*
 167          * On SMT machines we have to set the run latch in the ctrl register
 168          * in order to make PMC6 spin.
 169          */
 170         if (cpu_has_feature(CPU_FTR_SMT)) {
 171                 ctrl = mfspr(CTRLF);
 172                 ctrl |= RUNLATCH;
 173                 mtspr(CTRLT, ctrl);
 174         }
 175 #endif /* CONFIG_PPC_PSERIES */
 176 }
 177
 178 #else
 179
 180 /* PMC stuff */
 181 void ppc64_enable_pmcs(void)
 182 {
 183         /* XXX Implement for iseries */
 184 }
 185 #endif /* CONFIG_PPC_MULTIPLATFORM */
 186
 187 EXPORT_SYMBOL(ppc64_enable_pmcs);
 188
 189 /* XXX convert to rusty's on_one_cpu */
 190 static unsigned long run_on_cpu(unsigned long cpu,
 191                                 unsigned long (*func)(unsigned long),
 192                                 unsigned long arg)
 193 {
 194         cpumask_t old_affinity = current->cpus_allowed;
 195         unsigned long ret;
 196
 197         /* should return -EINVAL to userspace */
 198         if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
 199                 return 0;
 200
 201         ret = func(arg);
 202
 203         set_cpus_allowed(current, old_affinity);
 204
 205         return ret;
 206 }
 207
 208 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
 209 static unsigned long read_##NAME(unsigned long junk) \
 210 { \
 211         return mfspr(ADDRESS); \
 212 } \
 213 static unsigned long write_##NAME(unsigned long val) \
 214 { \
 215         ppc64_enable_pmcs(); \
 216         mtspr(ADDRESS, val); \
 217         return 0; \
 218 } \
 219 static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
 220 { \
 221         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 222         unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
 223         return sprintf(buf, "%lx\n", val); \
 224 } \
 225 static ssize_t __attribute_used__ \
 226         store_##NAME(struct sys_device *dev, const char *buf, size_t count) \
 227 { \
 228         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 229         unsigned long val; \
 230         int ret = sscanf(buf, "%lx", &val); \
 231         if (ret != 1) \
 232                 return -EINVAL; \
 233         run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
 234         return count; \
 235 }
 236
 237 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 238 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 239 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 240 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 241 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 242 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 243 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 244 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 245 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 246 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 247 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 248 SYSFS_PMCSETUP(purr, SPRN_PURR);
 249
 250 static SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0);
 251 static SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1);
 252 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 253 static SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1);
 254 static SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2);
 255 static SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3);
 256 static SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4);
 257 static SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5);
 258 static SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6);
 259 static SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7);
 260 static SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8);
 261 static SYSDEV_ATTR(purr, 0600, show_purr, NULL);
 262
 263 static void register_cpu_online(unsigned int cpu)
 264 {
 265         struct cpu *c = &per_cpu(cpu_devices, cpu);
 266         struct sys_device *s = &c->sysdev;
 267
 268 #ifndef CONFIG_PPC_ISERIES
 269         if (cpu_has_feature(CPU_FTR_SMT))
 270                 sysdev_create_file(s, &attr_smt_snooze_delay);
 271 #endif
 272
 273         /* PMC stuff */
 274
 275         sysdev_create_file(s, &attr_mmcr0);
 276         sysdev_create_file(s, &attr_mmcr1);
 277
 278         if (cpu_has_feature(CPU_FTR_MMCRA))
 279                 sysdev_create_file(s, &attr_mmcra);
 280
 281         sysdev_create_file(s, &attr_pmc1);
 282         sysdev_create_file(s, &attr_pmc2);
 283         sysdev_create_file(s, &attr_pmc3);
 284         sysdev_create_file(s, &attr_pmc4);
 285         sysdev_create_file(s, &attr_pmc5);
 286         sysdev_create_file(s, &attr_pmc6);
 287
 288         if (cpu_has_feature(CPU_FTR_PMC8)) {
 289                 sysdev_create_file(s, &attr_pmc7);
 290                 sysdev_create_file(s, &attr_pmc8);
 291         }
 292
 293         if (cpu_has_feature(CPU_FTR_SMT))
 294                 sysdev_create_file(s, &attr_purr);
 295 }
 296
 297 #ifdef CONFIG_HOTPLUG_CPU
 298 static void unregister_cpu_online(unsigned int cpu)
 299 {
 300         struct cpu *c = &per_cpu(cpu_devices, cpu);
 301         struct sys_device *s = &c->sysdev;
 302
 303         BUG_ON(c->no_control);
 304
 305 #ifndef CONFIG_PPC_ISERIES
 306         if (cpu_has_feature(CPU_FTR_SMT))
 307                 sysdev_remove_file(s, &attr_smt_snooze_delay);
 308 #endif
 309
 310         /* PMC stuff */
 311
 312         sysdev_remove_file(s, &attr_mmcr0);
 313         sysdev_remove_file(s, &attr_mmcr1);
 314
 315         if (cpu_has_feature(CPU_FTR_MMCRA))
 316                 sysdev_remove_file(s, &attr_mmcra);
 317
 318         sysdev_remove_file(s, &attr_pmc1);
 319         sysdev_remove_file(s, &attr_pmc2);
 320         sysdev_remove_file(s, &attr_pmc3);
 321         sysdev_remove_file(s, &attr_pmc4);
 322         sysdev_remove_file(s, &attr_pmc5);
 323         sysdev_remove_file(s, &attr_pmc6);
 324
 325         if (cpu_has_feature(CPU_FTR_PMC8)) {
 326                 sysdev_remove_file(s, &attr_pmc7);
 327                 sysdev_remove_file(s, &attr_pmc8);
 328         }
 329
 330         if (cpu_has_feature(CPU_FTR_SMT))
 331                 sysdev_remove_file(s, &attr_purr);
 332 }
 333 #endif /* CONFIG_HOTPLUG_CPU */
 334
 335 static int __devinit sysfs_cpu_notify(struct notifier_block *self,
 336                                       unsigned long action, void *hcpu)
 337 {
 338         unsigned int cpu = (unsigned int)(long)hcpu;
 339
 340         switch (action) {
 341         case CPU_ONLINE:
 342                 register_cpu_online(cpu);
 343                 break;
 344 #ifdef CONFIG_HOTPLUG_CPU
 345         case CPU_DEAD:
 346                 unregister_cpu_online(cpu);
 347                 break;
 348 #endif
 349         }
 350         return NOTIFY_OK;
 351 }
 352
 353 static struct notifier_block __devinitdata sysfs_cpu_nb = {
 354         .notifier_call  = sysfs_cpu_notify,
 355 };
 356
 357 /* NUMA stuff */
 358
 359 #ifdef CONFIG_NUMA
 360 static struct node node_devices[MAX_NUMNODES];
 361
 362 static void register_nodes(void)
 363 {
 364         int i;
 365
 366         for (i = 0; i < MAX_NUMNODES; i++) {
 367                 if (node_online(i)) {
 368                         int p_node = parent_node(i);
 369                         struct node *parent = NULL;
 370
 371                         if (p_node != i)
 372                                 parent = &node_devices[p_node];
 373
 374                         register_node(&node_devices[i], i, parent);
 375                 }
 376         }
 377 }
 378 #else
 379 static void register_nodes(void)
 380 {
 381         return;
 382 }
 383 #endif
 384
 385 /* Only valid if CPU is present. */
 386 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 387 {
 388         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 389
 390         return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
 391 }
 392 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 393
 394 static int __init topology_init(void)
 395 {
 396         int cpu;
 397         struct node *parent = NULL;
 398
 399         register_nodes();
 400
 401         register_cpu_notifier(&sysfs_cpu_nb);
 402
 403         for_each_cpu(cpu) {
 404                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 405
 406 #ifdef CONFIG_NUMA
 407                 parent = &node_devices[cpu_to_node(cpu)];
 408 #endif
 409                 /*
 410                  * For now, we just see if the system supports making
 411                  * the RTAS calls for CPU hotplug.  But, there may be a
 412                  * more comprehensive way to do this for an individual
 413                  * CPU.  For instance, the boot cpu might never be valid
 414                  * for hotplugging.
 415                  */
 416                 if (!ppc_md.cpu_die)
 417                         c->no_control = 1;
 418
 419                 if (cpu_online(cpu) || (c->no_control == 0)) {
 420                         register_cpu(c, cpu, parent);
 421
 422                         sysdev_create_file(&c->sysdev, &attr_physical_id);
 423                 }
 424
 425                 if (cpu_online(cpu))
 426                         register_cpu_online(cpu);
 427         }
 428
 429         return 0;
 430 }
 431 __initcall(topology_init);