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 #endif /* CONFIG_PPC_PSERIES */
 116
 117         /* Only need to enable them once */
 118         if (__get_cpu_var(pmcs_enabled))
 119                 return;
 120
 121         __get_cpu_var(pmcs_enabled) = 1;
 122
 123         switch (systemcfg->platform) {
 124         case PLATFORM_PSERIES:
 125         case PLATFORM_POWERMAC:
 126                 hid0 = mfspr(HID0);
 127                 hid0 |= 1UL << (63 - 20);
 128
 129                 /* POWER4 requires the following sequence */
 130                 asm volatile(
 131                              "sync\n"
 132                              "mtspr     %1, %0\n"
 133                              "mfspr     %0, %1\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                              "isync" : "=&r" (hid0) : "i" (HID0), "0" (hid0):
 140                              "memory");
 141                 break;
 142
 143 #ifdef CONFIG_PPC_PSERIES
 144         case PLATFORM_PSERIES_LPAR:
 145                 set = 1UL << 63;
 146                 reset = 0;
 147                 plpar_hcall_norets(H_PERFMON, set, reset);
 148                 break;
 149 #endif /* CONFIG_PPC_PSERIES */
 150
 151         default:
 152                 break;
 153         }
 154
 155 #ifdef CONFIG_PPC_PSERIES
 156         /* instruct hypervisor to maintain PMCs */
 157         if (ppc64_firmware_features & FW_FEATURE_SPLPAR)
 158                 get_paca()->lppaca.pmcregs_in_use = 1;
 159 #endif /* CONFIG_PPC_PSERIES */
 160 }
 161
 162 #else
 163
 164 /* PMC stuff */
 165 void ppc64_enable_pmcs(void)
 166 {
 167         /* XXX Implement for iseries */
 168 }
 169 #endif /* CONFIG_PPC_MULTIPLATFORM */
 170
 171 EXPORT_SYMBOL(ppc64_enable_pmcs);
 172
 173 /* XXX convert to rusty's on_one_cpu */
 174 static unsigned long run_on_cpu(unsigned long cpu,
 175                                 unsigned long (*func)(unsigned long),
 176                                 unsigned long arg)
 177 {
 178         cpumask_t old_affinity = current->cpus_allowed;
 179         unsigned long ret;
 180
 181         /* should return -EINVAL to userspace */
 182         if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
 183                 return 0;
 184
 185         ret = func(arg);
 186
 187         set_cpus_allowed(current, old_affinity);
 188
 189         return ret;
 190 }
 191
 192 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
 193 static unsigned long read_##NAME(unsigned long junk) \
 194 { \
 195         return mfspr(ADDRESS); \
 196 } \
 197 static unsigned long write_##NAME(unsigned long val) \
 198 { \
 199         ppc64_enable_pmcs(); \
 200         mtspr(ADDRESS, val); \
 201         return 0; \
 202 } \
 203 static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
 204 { \
 205         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 206         unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
 207         return sprintf(buf, "%lx\n", val); \
 208 } \
 209 static ssize_t __attribute_used__ \
 210         store_##NAME(struct sys_device *dev, const char *buf, size_t count) \
 211 { \
 212         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 213         unsigned long val; \
 214         int ret = sscanf(buf, "%lx", &val); \
 215         if (ret != 1) \
 216                 return -EINVAL; \
 217         run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
 218         return count; \
 219 }
 220
 221 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 222 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 223 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 224 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 225 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 226 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 227 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 228 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 229 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 230 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 231 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 232 SYSFS_PMCSETUP(purr, SPRN_PURR);
 233
 234 static SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0);
 235 static SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1);
 236 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 237 static SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1);
 238 static SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2);
 239 static SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3);
 240 static SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4);
 241 static SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5);
 242 static SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6);
 243 static SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7);
 244 static SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8);
 245 static SYSDEV_ATTR(purr, 0600, show_purr, NULL);
 246
 247 static void register_cpu_online(unsigned int cpu)
 248 {
 249         struct cpu *c = &per_cpu(cpu_devices, cpu);
 250         struct sys_device *s = &c->sysdev;
 251
 252 #ifndef CONFIG_PPC_ISERIES
 253         if (cpu_has_feature(CPU_FTR_SMT))
 254                 sysdev_create_file(s, &attr_smt_snooze_delay);
 255 #endif
 256
 257         /* PMC stuff */
 258
 259         sysdev_create_file(s, &attr_mmcr0);
 260         sysdev_create_file(s, &attr_mmcr1);
 261
 262         if (cpu_has_feature(CPU_FTR_MMCRA))
 263                 sysdev_create_file(s, &attr_mmcra);
 264
 265         sysdev_create_file(s, &attr_pmc1);
 266         sysdev_create_file(s, &attr_pmc2);
 267         sysdev_create_file(s, &attr_pmc3);
 268         sysdev_create_file(s, &attr_pmc4);
 269         sysdev_create_file(s, &attr_pmc5);
 270         sysdev_create_file(s, &attr_pmc6);
 271
 272         if (cpu_has_feature(CPU_FTR_PMC8)) {
 273                 sysdev_create_file(s, &attr_pmc7);
 274                 sysdev_create_file(s, &attr_pmc8);
 275         }
 276
 277         if (cpu_has_feature(CPU_FTR_SMT))
 278                 sysdev_create_file(s, &attr_purr);
 279 }
 280
 281 #ifdef CONFIG_HOTPLUG_CPU
 282 static void unregister_cpu_online(unsigned int cpu)
 283 {
 284         struct cpu *c = &per_cpu(cpu_devices, cpu);
 285         struct sys_device *s = &c->sysdev;
 286
 287         BUG_ON(c->no_control);
 288
 289 #ifndef CONFIG_PPC_ISERIES
 290         if (cpu_has_feature(CPU_FTR_SMT))
 291                 sysdev_remove_file(s, &attr_smt_snooze_delay);
 292 #endif
 293
 294         /* PMC stuff */
 295
 296         sysdev_remove_file(s, &attr_mmcr0);
 297         sysdev_remove_file(s, &attr_mmcr1);
 298
 299         if (cpu_has_feature(CPU_FTR_MMCRA))
 300                 sysdev_remove_file(s, &attr_mmcra);
 301
 302         sysdev_remove_file(s, &attr_pmc1);
 303         sysdev_remove_file(s, &attr_pmc2);
 304         sysdev_remove_file(s, &attr_pmc3);
 305         sysdev_remove_file(s, &attr_pmc4);
 306         sysdev_remove_file(s, &attr_pmc5);
 307         sysdev_remove_file(s, &attr_pmc6);
 308
 309         if (cpu_has_feature(CPU_FTR_PMC8)) {
 310                 sysdev_remove_file(s, &attr_pmc7);
 311                 sysdev_remove_file(s, &attr_pmc8);
 312         }
 313
 314         if (cpu_has_feature(CPU_FTR_SMT))
 315                 sysdev_remove_file(s, &attr_purr);
 316 }
 317 #endif /* CONFIG_HOTPLUG_CPU */
 318
 319 static int __devinit sysfs_cpu_notify(struct notifier_block *self,
 320                                       unsigned long action, void *hcpu)
 321 {
 322         unsigned int cpu = (unsigned int)(long)hcpu;
 323
 324         switch (action) {
 325         case CPU_ONLINE:
 326                 register_cpu_online(cpu);
 327                 break;
 328 #ifdef CONFIG_HOTPLUG_CPU
 329         case CPU_DEAD:
 330                 unregister_cpu_online(cpu);
 331                 break;
 332 #endif
 333         }
 334         return NOTIFY_OK;
 335 }
 336
 337 static struct notifier_block __devinitdata sysfs_cpu_nb = {
 338         .notifier_call  = sysfs_cpu_notify,
 339 };
 340
 341 /* NUMA stuff */
 342
 343 #ifdef CONFIG_NUMA
 344 static struct node node_devices[MAX_NUMNODES];
 345
 346 static void register_nodes(void)
 347 {
 348         int i;
 349
 350         for (i = 0; i < MAX_NUMNODES; i++) {
 351                 if (node_online(i)) {
 352                         int p_node = parent_node(i);
 353                         struct node *parent = NULL;
 354
 355                         if (p_node != i)
 356                                 parent = &node_devices[p_node];
 357
 358                         register_node(&node_devices[i], i, parent);
 359                 }
 360         }
 361 }
 362 #else
 363 static void register_nodes(void)
 364 {
 365         return;
 366 }
 367 #endif
 368
 369 /* Only valid if CPU is present. */
 370 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 371 {
 372         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 373
 374         return sprintf(buf, "%d\n", get_hard_smp_processor_id(cpu->sysdev.id));
 375 }
 376 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 377
 378 static int __init topology_init(void)
 379 {
 380         int cpu;
 381         struct node *parent = NULL;
 382
 383         register_nodes();
 384
 385         register_cpu_notifier(&sysfs_cpu_nb);
 386
 387         for_each_cpu(cpu) {
 388                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 389
 390 #ifdef CONFIG_NUMA
 391                 /* The node to which a cpu belongs can't be known
 392                  * until the cpu is made present.
 393                  */
 394                 parent = NULL;
 395                 if (cpu_present(cpu))
 396                         parent = &node_devices[cpu_to_node(cpu)];
 397 #endif
 398                 /*
 399                  * For now, we just see if the system supports making
 400                  * the RTAS calls for CPU hotplug.  But, there may be a
 401                  * more comprehensive way to do this for an individual
 402                  * CPU.  For instance, the boot cpu might never be valid
 403                  * for hotplugging.
 404                  */
 405                 if (!ppc_md.cpu_die)
 406                         c->no_control = 1;
 407
 408                 if (cpu_online(cpu) || (c->no_control == 0)) {
 409                         register_cpu(c, cpu, parent);
 410
 411                         sysdev_create_file(&c->sysdev, &attr_physical_id);
 412                 }
 413
 414                 if (cpu_online(cpu))
 415                         register_cpu_online(cpu);
 416         }
 417
 418         return 0;
 419 }
 420 __initcall(topology_init);