LXR linux/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
  22
  23static DEFINE_PER_CPU(struct cpu, cpu_devices);
  24
  25/* SMT stuff */
  26
  27#ifdef CONFIG_PPC_MULTIPLATFORM
  28/* default to snooze disabled */
  29DEFINE_PER_CPU(unsigned long, smt_snooze_delay);
  30
  31static 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
  47static 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
  54static 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 */
  58static int smt_snooze_cmdline;
  59
  60static int __init smt_setup(void)
  61{
  62        struct device_node *options;
  63        unsigned int *val;
  64        unsigned int cpu;
  65
  66        if (!cur_cpu_spec->cpu_features & 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
  84static int __init setup_smt_snooze_delay(char *str)
  85{
  86        unsigned int cpu;
  87        int snooze;
  88
  89        if (!cur_cpu_spec->cpu_features & 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
 108static DEFINE_PER_CPU(char, pmcs_enabled);
 109
 110void 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 (cur_cpu_spec->cpu_features & 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 */
 181void ppc64_enable_pmcs(void)
 182{
 183        /* XXX Implement for iseries */
 184}
 185#endif /* CONFIG_PPC_MULTIPLATFORM */
 186
 187EXPORT_SYMBOL(ppc64_enable_pmcs);
 188
 189/* XXX convert to rusty's on_one_cpu */
 190static 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) \
 209static unsigned long read_##NAME(unsigned long junk) \
 210{ \
 211        return mfspr(ADDRESS); \
 212} \
 213static unsigned long write_##NAME(unsigned long val) \
 214{ \
 215        ppc64_enable_pmcs(); \
 216        mtspr(ADDRESS, val); \
 217        return 0; \
 218} \
 219static 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} \
 225static 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
 237SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 238SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 239SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 240SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 241SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 242SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 243SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 244SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 245SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 246SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 247SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 248SYSFS_PMCSETUP(purr, SPRN_PURR);
 249
 250static SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0);
 251static SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1);
 252static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 253static SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1);
 254static SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2);
 255static SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3);
 256static SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4);
 257static SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5);
 258static SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6);
 259static SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7);
 260static SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8);
 261static SYSDEV_ATTR(purr, 0600, show_purr, NULL);
 262
 263static 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 (cur_cpu_spec->cpu_features & 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 (cur_cpu_spec->cpu_features & 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 (cur_cpu_spec->cpu_features & CPU_FTR_PMC8) {
 289                sysdev_create_file(s, &attr_pmc7);
 290                sysdev_create_file(s, &attr_pmc8);
 291        }
 292
 293        if (cur_cpu_spec->cpu_features & CPU_FTR_SMT)
 294                sysdev_create_file(s, &attr_purr);
 295}
 296
 297#ifdef CONFIG_HOTPLUG_CPU
 298static 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 (cur_cpu_spec->cpu_features & 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 (cur_cpu_spec->cpu_features & 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 (cur_cpu_spec->cpu_features & CPU_FTR_PMC8) {
 326                sysdev_remove_file(s, &attr_pmc7);
 327                sysdev_remove_file(s, &attr_pmc8);
 328        }
 329
 330        if (cur_cpu_spec->cpu_features & CPU_FTR_SMT)
 331                sysdev_remove_file(s, &attr_purr);
 332}
 333#endif /* CONFIG_HOTPLUG_CPU */
 334
 335static 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
 353static struct notifier_block __devinitdata sysfs_cpu_nb = {
 354        .notifier_call  = sysfs_cpu_notify,
 355};
 356
 357/* NUMA stuff */
 358
 359#ifdef CONFIG_NUMA
 360static struct node node_devices[MAX_NUMNODES];
 361
 362static 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
 379static void register_nodes(void)
 380{
 381        return;
 382}
 383#endif
 384
 385/* Only valid if CPU is present. */
 386static 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}
 392static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 393
 394static 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#ifdef CONFIG_HOTPLUG_CPU
 417                if (systemcfg->platform != PLATFORM_PSERIES_LPAR)
 418#endif
 419                        c->no_control = 1;
 420
 421                if (cpu_online(cpu) || (c->no_control == 0)) {
 422                        register_cpu(c, cpu, parent);
 423
 424                        sysdev_create_file(&c->sysdev, &attr_physical_id);
 425                }
 426
 427                if (cpu_online(cpu))
 428                        register_cpu_online(cpu);
 429        }
 430
 431        return 0;
 432}
 433__initcall(topology_init);
 434