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 #endif /* CONFIG_PPC_PSERIES */
 117
 118         /* Only need to enable them once */
 119         if (__get_cpu_var(pmcs_enabled))
 120                 return;
 121
 122         __get_cpu_var(pmcs_enabled) = 1;
 123
 124         switch (systemcfg->platform) {
 125         case PLATFORM_PSERIES:
 126         case PLATFORM_POWERMAC:
 127                 hid0 = mfspr(HID0);
 128                 hid0 |= 1UL << (63 - 20);
 129
 130                 /* POWER4 requires the following sequence */
 131                 asm volatile(
 132                              "sync\n"
 133                              "mtspr     %1, %0\n"
 134                              "mfspr     %0, %1\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                              "isync" : "=&r" (hid0) : "i" (HID0), "0" (hid0):
 141                              "memory");
 142                 break;
 143
 144 #ifdef CONFIG_PPC_PSERIES
 145         case PLATFORM_PSERIES_LPAR:
 146                 set = 1UL << 63;
 147                 reset = 0;
 148                 ret = plpar_hcall_norets(H_PERFMON, set, reset);
 149                 if (ret)
 150                         printk(KERN_ERR "H_PERFMON call on cpu %u "
 151                                "returned %d\n",
 152                                smp_processor_id(), ret);
 153                 break;
 154 #endif /* CONFIG_PPC_PSERIES */
 155
 156         default:
 157                 break;
 158         }
 159
 160 #ifdef CONFIG_PPC_PSERIES
 161         /* instruct hypervisor to maintain PMCs */
 162         if (cur_cpu_spec->firmware_features & FW_FEATURE_SPLPAR)
 163                 get_paca()->lppaca.pmcregs_in_use = 1;
 164
 165         /*
 166          * On SMT machines we have to set the run latch in the ctrl register
 167          * in order to make PMC6 spin.
 168          */
 169         if (cpu_has_feature(CPU_FTR_SMT))
 170                 ppc64_runlatch_on();
 171 #endif /* CONFIG_PPC_PSERIES */
 172 }
 173
 174 #else
 175
 176 /* PMC stuff */
 177 void ppc64_enable_pmcs(void)
 178 {
 179         /* XXX Implement for iseries */
 180 }
 181 #endif /* CONFIG_PPC_MULTIPLATFORM */
 182
 183 EXPORT_SYMBOL(ppc64_enable_pmcs);
 184
 185 /* XXX convert to rusty's on_one_cpu */
 186 static unsigned long run_on_cpu(unsigned long cpu,
 187                                 unsigned long (*func)(unsigned long),
 188                                 unsigned long arg)
 189 {
 190         cpumask_t old_affinity = current->cpus_allowed;
 191         unsigned long ret;
 192
 193         /* should return -EINVAL to userspace */
 194         if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
 195                 return 0;
 196
 197         ret = func(arg);
 198
 199         set_cpus_allowed(current, old_affinity);
 200
 201         return ret;
 202 }
 203
 204 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
 205 static unsigned long read_##NAME(unsigned long junk) \
 206 { \
 207         return mfspr(ADDRESS); \
 208 } \
 209 static unsigned long write_##NAME(unsigned long val) \
 210 { \
 211         ppc64_enable_pmcs(); \
 212         mtspr(ADDRESS, val); \
 213         return 0; \
 214 } \
 215 static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
 216 { \
 217         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 218         unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
 219         return sprintf(buf, "%lx\n", val); \
 220 } \
 221 static ssize_t __attribute_used__ \
 222         store_##NAME(struct sys_device *dev, const char *buf, size_t count) \
 223 { \
 224         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 225         unsigned long val; \
 226         int ret = sscanf(buf, "%lx", &val); \
 227         if (ret != 1) \
 228                 return -EINVAL; \
 229         run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
 230         return count; \
 231 }
 232
 233 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 234 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 235 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 236 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 237 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 238 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 239 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 240 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 241 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 242 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 243 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 244 SYSFS_PMCSETUP(purr, SPRN_PURR);
 245
 246 static SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0);
 247 static SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1);
 248 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 249 static SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1);
 250 static SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2);
 251 static SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3);
 252 static SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4);
 253 static SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5);
 254 static SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6);
 255 static SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7);
 256 static SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8);
 257 static SYSDEV_ATTR(purr, 0600, show_purr, NULL);
 258
 259 static void register_cpu_online(unsigned int cpu)
 260 {
 261         struct cpu *c = &per_cpu(cpu_devices, cpu);
 262         struct sys_device *s = &c->sysdev;
 263
 264 #ifndef CONFIG_PPC_ISERIES
 265         if (cpu_has_feature(CPU_FTR_SMT))
 266                 sysdev_create_file(s, &attr_smt_snooze_delay);
 267 #endif
 268
 269         /* PMC stuff */
 270
 271         sysdev_create_file(s, &attr_mmcr0);
 272         sysdev_create_file(s, &attr_mmcr1);
 273
 274         if (cpu_has_feature(CPU_FTR_MMCRA))
 275                 sysdev_create_file(s, &attr_mmcra);
 276
 277         sysdev_create_file(s, &attr_pmc1);
 278         sysdev_create_file(s, &attr_pmc2);
 279         sysdev_create_file(s, &attr_pmc3);
 280         sysdev_create_file(s, &attr_pmc4);
 281         sysdev_create_file(s, &attr_pmc5);
 282         sysdev_create_file(s, &attr_pmc6);
 283
 284         if (cpu_has_feature(CPU_FTR_PMC8)) {
 285                 sysdev_create_file(s, &attr_pmc7);
 286                 sysdev_create_file(s, &attr_pmc8);
 287         }
 288
 289         if (cpu_has_feature(CPU_FTR_SMT))
 290                 sysdev_create_file(s, &attr_purr);
 291 }
 292
 293 #ifdef CONFIG_HOTPLUG_CPU
 294 static void unregister_cpu_online(unsigned int cpu)
 295 {
 296         struct cpu *c = &per_cpu(cpu_devices, cpu);
 297         struct sys_device *s = &c->sysdev;
 298
 299         BUG_ON(c->no_control);
 300
 301 #ifndef CONFIG_PPC_ISERIES
 302         if (cpu_has_feature(CPU_FTR_SMT))
 303                 sysdev_remove_file(s, &attr_smt_snooze_delay);
 304 #endif
 305
 306         /* PMC stuff */
 307
 308         sysdev_remove_file(s, &attr_mmcr0);
 309         sysdev_remove_file(s, &attr_mmcr1);
 310
 311         if (cpu_has_feature(CPU_FTR_MMCRA))
 312                 sysdev_remove_file(s, &attr_mmcra);
 313
 314         sysdev_remove_file(s, &attr_pmc1);
 315         sysdev_remove_file(s, &attr_pmc2);
 316         sysdev_remove_file(s, &attr_pmc3);
 317         sysdev_remove_file(s, &attr_pmc4);
 318         sysdev_remove_file(s, &attr_pmc5);
 319         sysdev_remove_file(s, &attr_pmc6);
 320
 321         if (cpu_has_feature(CPU_FTR_PMC8)) {
 322                 sysdev_remove_file(s, &attr_pmc7);
 323                 sysdev_remove_file(s, &attr_pmc8);
 324         }
 325
 326         if (cpu_has_feature(CPU_FTR_SMT))
 327                 sysdev_remove_file(s, &attr_purr);
 328 }
 329 #endif /* CONFIG_HOTPLUG_CPU */
 330
 331 static int __devinit sysfs_cpu_notify(struct notifier_block *self,
 332                                       unsigned long action, void *hcpu)
 333 {
 334         unsigned int cpu = (unsigned int)(long)hcpu;
 335
 336         switch (action) {
 337         case CPU_ONLINE:
 338                 register_cpu_online(cpu);
 339                 break;
 340 #ifdef CONFIG_HOTPLUG_CPU
 341         case CPU_DEAD:
 342                 unregister_cpu_online(cpu);
 343                 break;
 344 #endif
 345         }
 346         return NOTIFY_OK;
 347 }
 348
 349 static struct notifier_block __devinitdata sysfs_cpu_nb = {
 350         .notifier_call  = sysfs_cpu_notify,
 351 };
 352
 353 /* NUMA stuff */
 354
 355 #ifdef CONFIG_NUMA
 356 static struct node node_devices[MAX_NUMNODES];
 357
 358 static void register_nodes(void)
 359 {
 360         int i;
 361
 362         for (i = 0; i < MAX_NUMNODES; i++) {
 363                 if (node_online(i)) {
 364                         int p_node = parent_node(i);
 365                         struct node *parent = NULL;
 366
 367                         if (p_node != i)
 368                                 parent = &node_devices[p_node];
 369
 370                         register_node(&node_devices[i], i, parent);
 371                 }
 372         }
 373 }
 374 #else
 375 static void register_nodes(void)
 376 {
 377         return;
 378 }
 379 #endif
 380
 381 /* Only valid if CPU is present. */
 382 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 383 {
 384         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 385
 386         return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
 387 }
 388 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 389
 390 static int __init topology_init(void)
 391 {
 392         int cpu;
 393         struct node *parent = NULL;
 394
 395         register_nodes();
 396
 397         register_cpu_notifier(&sysfs_cpu_nb);
 398
 399         for_each_cpu(cpu) {
 400                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 401
 402 #ifdef CONFIG_NUMA
 403                 /* The node to which a cpu belongs can't be known
 404                  * until the cpu is made present.
 405                  */
 406                 parent = NULL;
 407                 if (cpu_present(cpu))
 408                         parent = &node_devices[cpu_to_node(cpu)];
 409 #endif
 410                 /*
 411                  * For now, we just see if the system supports making
 412                  * the RTAS calls for CPU hotplug.  But, there may be a
 413                  * more comprehensive way to do this for an individual
 414                  * CPU.  For instance, the boot cpu might never be valid
 415                  * for hotplugging.
 416                  */
 417                 if (!ppc_md.cpu_die)
 418                         c->no_control = 1;
 419
 420                 if (cpu_online(cpu) || (c->no_control == 0)) {
 421                         register_cpu(c, cpu, parent);
 422
 423                         sysdev_create_file(&c->sysdev, &attr_physical_id);
 424                 }
 425
 426                 if (cpu_online(cpu))
 427                         register_cpu_online(cpu);
 428         }
 429
 430         return 0;
 431 }
 432 __initcall(topology_init);