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 <asm/current.h>
   9 #include <asm/processor.h>
  10 #include <asm/cputable.h>
  11 #include <asm/hvcall.h>
  12 #include <asm/prom.h>
  13
  14
  15 /* SMT stuff */
  16
  17 #ifndef CONFIG_PPC_ISERIES
  18
  19 /* default to snooze disabled */
  20 DEFINE_PER_CPU(unsigned long, smt_snooze_delay);
  21
  22 static ssize_t store_smt_snooze_delay(struct sys_device *dev, const char *buf,
  23                                       size_t count)
  24 {
  25         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
  26         ssize_t ret;
  27         unsigned long snooze;
  28
  29         ret = sscanf(buf, "%lu", &snooze);
  30         if (ret != 1)
  31                 return -EINVAL;
  32
  33         per_cpu(smt_snooze_delay, cpu->sysdev.id) = snooze;
  34
  35         return count;
  36 }
  37
  38 static ssize_t show_smt_snooze_delay(struct sys_device *dev, char *buf)
  39 {
  40         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
  41
  42         return sprintf(buf, "%lu\n", per_cpu(smt_snooze_delay, cpu->sysdev.id));
  43 }
  44
  45 static SYSDEV_ATTR(smt_snooze_delay, 0644, show_smt_snooze_delay,
  46                    store_smt_snooze_delay);
  47
  48 /* Only parse OF options if the matching cmdline option was not specified */
  49 static int smt_snooze_cmdline;
  50
  51 static int __init smt_setup(void)
  52 {
  53         struct device_node *options;
  54         unsigned int *val;
  55         unsigned int cpu;
  56
  57         if (!cur_cpu_spec->cpu_features & CPU_FTR_SMT)
  58                 return 1;
  59
  60         options = find_path_device("/options");
  61         if (!options)
  62                 return 1;
  63
  64         val = (unsigned int *)get_property(options, "ibm,smt-snooze-delay",
  65                                            NULL);
  66         if (!smt_snooze_cmdline && val) {
  67                 for_each_cpu(cpu)
  68                         per_cpu(smt_snooze_delay, cpu) = *val;
  69         }
  70
  71         return 1;
  72 }
  73 __initcall(smt_setup);
  74
  75 static int __init setup_smt_snooze_delay(char *str)
  76 {
  77         unsigned int cpu;
  78         int snooze;
  79
  80         if (!cur_cpu_spec->cpu_features & CPU_FTR_SMT)
  81                 return 1;
  82
  83         smt_snooze_cmdline = 1;
  84
  85         if (get_option(&str, &snooze)) {
  86                 for_each_cpu(cpu)
  87                         per_cpu(smt_snooze_delay, cpu) = snooze;
  88         }
  89
  90         return 1;
  91 }
  92 __setup("smt-snooze-delay=", setup_smt_snooze_delay);
  93
  94 #endif
  95
  96
  97 /* PMC stuff */
  98
  99 /*
 100  * Enabling PMCs will slow partition context switch times so we only do
 101  * it the first time we write to the PMCs.
 102  */
 103
 104 static DEFINE_PER_CPU(char, pmcs_enabled);
 105
 106 #ifdef CONFIG_PPC_ISERIES
 107 void ppc64_enable_pmcs(void)
 108 {
 109         /* XXX Implement for iseries */
 110 }
 111 #else
 112 void ppc64_enable_pmcs(void)
 113 {
 114         unsigned long hid0;
 115         unsigned long set, reset;
 116         int ret;
 117         unsigned int ctrl;
 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                         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                 case PLATFORM_PSERIES_LPAR:
 145                         set = 1UL << 63;
 146                         reset = 0;
 147                         ret = plpar_hcall_norets(H_PERFMON, set, reset);
 148                         if (ret)
 149                                 printk(KERN_ERR "H_PERFMON call returned %d",
 150                                        ret);
 151                         break;
 152
 153                 default:
 154                         break;
 155         }
 156
 157         /* instruct hypervisor to maintain PMCs */
 158         if (cur_cpu_spec->firmware_features & FW_FEATURE_SPLPAR) {
 159                 char *ptr = (char *)&paca[smp_processor_id()].xLpPaca;
 160                 ptr[0xBB] = 1;
 161         }
 162
 163         /*
 164          * On SMT machines we have to set the run latch in the ctrl register
 165          * in order to make PMC6 spin.
 166          */
 167         if (cur_cpu_spec->cpu_features & CPU_FTR_SMT) {
 168                 ctrl = mfspr(CTRLF);
 169                 ctrl |= RUNLATCH;
 170                 mtspr(CTRLT, ctrl);
 171         }
 172 }
 173 #endif
 174
 175 /* XXX convert to rusty's on_one_cpu */
 176 static unsigned long run_on_cpu(unsigned long cpu,
 177                                 unsigned long (*func)(unsigned long),
 178                                 unsigned long arg)
 179 {
 180         cpumask_t old_affinity = current->cpus_allowed;
 181         unsigned long ret;
 182
 183         /* should return -EINVAL to userspace */
 184         if (set_cpus_allowed(current, cpumask_of_cpu(cpu)))
 185                 return 0;
 186
 187         ret = func(arg);
 188
 189         set_cpus_allowed(current, old_affinity);
 190
 191         return ret;
 192 }
 193
 194 #define SYSFS_PMCSETUP(NAME, ADDRESS) \
 195 static unsigned long read_##NAME(unsigned long junk) \
 196 { \
 197         return mfspr(ADDRESS); \
 198 } \
 199 static unsigned long write_##NAME(unsigned long val) \
 200 { \
 201         ppc64_enable_pmcs(); \
 202         mtspr(ADDRESS, val); \
 203         return 0; \
 204 } \
 205 static ssize_t show_##NAME(struct sys_device *dev, char *buf) \
 206 { \
 207         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 208         unsigned long val = run_on_cpu(cpu->sysdev.id, read_##NAME, 0); \
 209         return sprintf(buf, "%lx\n", val); \
 210 } \
 211 static ssize_t store_##NAME(struct sys_device *dev, const char *buf, \
 212                             size_t count) \
 213 { \
 214         struct cpu *cpu = container_of(dev, struct cpu, sysdev); \
 215         unsigned long val; \
 216         int ret = sscanf(buf, "%lx", &val); \
 217         if (ret != 1) \
 218                 return -EINVAL; \
 219         run_on_cpu(cpu->sysdev.id, write_##NAME, val); \
 220         return count; \
 221 }
 222
 223 SYSFS_PMCSETUP(mmcr0, SPRN_MMCR0);
 224 SYSFS_PMCSETUP(mmcr1, SPRN_MMCR1);
 225 SYSFS_PMCSETUP(mmcra, SPRN_MMCRA);
 226 SYSFS_PMCSETUP(pmc1, SPRN_PMC1);
 227 SYSFS_PMCSETUP(pmc2, SPRN_PMC2);
 228 SYSFS_PMCSETUP(pmc3, SPRN_PMC3);
 229 SYSFS_PMCSETUP(pmc4, SPRN_PMC4);
 230 SYSFS_PMCSETUP(pmc5, SPRN_PMC5);
 231 SYSFS_PMCSETUP(pmc6, SPRN_PMC6);
 232 SYSFS_PMCSETUP(pmc7, SPRN_PMC7);
 233 SYSFS_PMCSETUP(pmc8, SPRN_PMC8);
 234 SYSFS_PMCSETUP(purr, SPRN_PURR);
 235
 236 static SYSDEV_ATTR(mmcr0, 0600, show_mmcr0, store_mmcr0);
 237 static SYSDEV_ATTR(mmcr1, 0600, show_mmcr1, store_mmcr1);
 238 static SYSDEV_ATTR(mmcra, 0600, show_mmcra, store_mmcra);
 239 static SYSDEV_ATTR(pmc1, 0600, show_pmc1, store_pmc1);
 240 static SYSDEV_ATTR(pmc2, 0600, show_pmc2, store_pmc2);
 241 static SYSDEV_ATTR(pmc3, 0600, show_pmc3, store_pmc3);
 242 static SYSDEV_ATTR(pmc4, 0600, show_pmc4, store_pmc4);
 243 static SYSDEV_ATTR(pmc5, 0600, show_pmc5, store_pmc5);
 244 static SYSDEV_ATTR(pmc6, 0600, show_pmc6, store_pmc6);
 245 static SYSDEV_ATTR(pmc7, 0600, show_pmc7, store_pmc7);
 246 static SYSDEV_ATTR(pmc8, 0600, show_pmc8, store_pmc8);
 247 static SYSDEV_ATTR(purr, 0600, show_purr, NULL);
 248
 249 static void __init register_cpu_pmc(struct sys_device *s)
 250 {
 251         sysdev_create_file(s, &attr_mmcr0);
 252         sysdev_create_file(s, &attr_mmcr1);
 253
 254         if (cur_cpu_spec->cpu_features & CPU_FTR_MMCRA)
 255                 sysdev_create_file(s, &attr_mmcra);
 256
 257         sysdev_create_file(s, &attr_pmc1);
 258         sysdev_create_file(s, &attr_pmc2);
 259         sysdev_create_file(s, &attr_pmc3);
 260         sysdev_create_file(s, &attr_pmc4);
 261         sysdev_create_file(s, &attr_pmc5);
 262         sysdev_create_file(s, &attr_pmc6);
 263
 264         if (cur_cpu_spec->cpu_features & CPU_FTR_PMC8) {
 265                 sysdev_create_file(s, &attr_pmc7);
 266                 sysdev_create_file(s, &attr_pmc8);
 267         }
 268
 269         if (cur_cpu_spec->cpu_features & CPU_FTR_SMT)
 270                 sysdev_create_file(s, &attr_purr);
 271 }
 272
 273
 274 /* NUMA stuff */
 275
 276 #ifdef CONFIG_NUMA
 277 static struct node node_devices[MAX_NUMNODES];
 278
 279 static void register_nodes(void)
 280 {
 281         int i;
 282
 283         for (i = 0; i < MAX_NUMNODES; i++) {
 284                 if (node_online(i)) {
 285                         int p_node = parent_node(i);
 286                         struct node *parent = NULL;
 287
 288                         if (p_node != i)
 289                                 parent = &node_devices[p_node];
 290
 291                         register_node(&node_devices[i], i, parent);
 292                 }
 293         }
 294 }
 295 #else
 296 static void register_nodes(void)
 297 {
 298         return;
 299 }
 300 #endif
 301
 302
 303 /* Only valid if CPU is online. */
 304 static ssize_t show_physical_id(struct sys_device *dev, char *buf)
 305 {
 306         struct cpu *cpu = container_of(dev, struct cpu, sysdev);
 307
 308         return sprintf(buf, "%u\n", get_hard_smp_processor_id(cpu->sysdev.id));
 309 }
 310 static SYSDEV_ATTR(physical_id, 0444, show_physical_id, NULL);
 311
 312
 313 static DEFINE_PER_CPU(struct cpu, cpu_devices);
 314
 315 static int __init topology_init(void)
 316 {
 317         int cpu;
 318         struct node *parent = NULL;
 319
 320         register_nodes();
 321
 322         for_each_cpu(cpu) {
 323                 struct cpu *c = &per_cpu(cpu_devices, cpu);
 324
 325 #ifdef CONFIG_NUMA
 326                 parent = &node_devices[cpu_to_node(cpu)];
 327 #endif
 328                 register_cpu(c, cpu, parent);
 329
 330                 register_cpu_pmc(&c->sysdev);
 331
 332                 sysdev_create_file(&c->sysdev, &attr_physical_id);
 333
 334 #ifndef CONFIG_PPC_ISERIES
 335                 if (cur_cpu_spec->cpu_features & CPU_FTR_SMT)
 336                         sysdev_create_file(&c->sysdev, &attr_smt_snooze_delay);
 337 #endif
 338         }
 339
 340         return 0;
 341 }
 342 __initcall(topology_init);