1*881730adSHeiko Carstens /* 2*881730adSHeiko Carstens * Extract CPU cache information and expose them via sysfs. 3*881730adSHeiko Carstens * 4*881730adSHeiko Carstens * Copyright IBM Corp. 2012 5*881730adSHeiko Carstens * Author(s): Heiko Carstens <heiko.carstens@de.ibm.com> 6*881730adSHeiko Carstens */ 7*881730adSHeiko Carstens 8*881730adSHeiko Carstens #include <linux/notifier.h> 9*881730adSHeiko Carstens #include <linux/init.h> 10*881730adSHeiko Carstens #include <linux/list.h> 11*881730adSHeiko Carstens #include <linux/slab.h> 12*881730adSHeiko Carstens #include <linux/cpu.h> 13*881730adSHeiko Carstens #include <asm/facility.h> 14*881730adSHeiko Carstens 15*881730adSHeiko Carstens struct cache { 16*881730adSHeiko Carstens unsigned long size; 17*881730adSHeiko Carstens unsigned int line_size; 18*881730adSHeiko Carstens unsigned int associativity; 19*881730adSHeiko Carstens unsigned int nr_sets; 20*881730adSHeiko Carstens int level; 21*881730adSHeiko Carstens int type; 22*881730adSHeiko Carstens struct list_head list; 23*881730adSHeiko Carstens }; 24*881730adSHeiko Carstens 25*881730adSHeiko Carstens struct cache_dir { 26*881730adSHeiko Carstens struct kobject *kobj; 27*881730adSHeiko Carstens struct cache_index_dir *index; 28*881730adSHeiko Carstens }; 29*881730adSHeiko Carstens 30*881730adSHeiko Carstens struct cache_index_dir { 31*881730adSHeiko Carstens struct kobject kobj; 32*881730adSHeiko Carstens int cpu; 33*881730adSHeiko Carstens struct cache *cache; 34*881730adSHeiko Carstens struct cache_index_dir *next; 35*881730adSHeiko Carstens }; 36*881730adSHeiko Carstens 37*881730adSHeiko Carstens enum { 38*881730adSHeiko Carstens CACHE_SCOPE_NOTEXISTS, 39*881730adSHeiko Carstens CACHE_SCOPE_PRIVATE, 40*881730adSHeiko Carstens CACHE_SCOPE_SHARED, 41*881730adSHeiko Carstens CACHE_SCOPE_RESERVED, 42*881730adSHeiko Carstens }; 43*881730adSHeiko Carstens 44*881730adSHeiko Carstens enum { 45*881730adSHeiko Carstens CACHE_TYPE_SEPARATE, 46*881730adSHeiko Carstens CACHE_TYPE_DATA, 47*881730adSHeiko Carstens CACHE_TYPE_INSTRUCTION, 48*881730adSHeiko Carstens CACHE_TYPE_UNIFIED, 49*881730adSHeiko Carstens }; 50*881730adSHeiko Carstens 51*881730adSHeiko Carstens enum { 52*881730adSHeiko Carstens EXTRACT_TOPOLOGY, 53*881730adSHeiko Carstens EXTRACT_LINE_SIZE, 54*881730adSHeiko Carstens EXTRACT_SIZE, 55*881730adSHeiko Carstens EXTRACT_ASSOCIATIVITY, 56*881730adSHeiko Carstens }; 57*881730adSHeiko Carstens 58*881730adSHeiko Carstens enum { 59*881730adSHeiko Carstens CACHE_TI_UNIFIED = 0, 60*881730adSHeiko Carstens CACHE_TI_INSTRUCTION = 0, 61*881730adSHeiko Carstens CACHE_TI_DATA, 62*881730adSHeiko Carstens }; 63*881730adSHeiko Carstens 64*881730adSHeiko Carstens struct cache_info { 65*881730adSHeiko Carstens unsigned char : 4; 66*881730adSHeiko Carstens unsigned char scope : 2; 67*881730adSHeiko Carstens unsigned char type : 2; 68*881730adSHeiko Carstens }; 69*881730adSHeiko Carstens 70*881730adSHeiko Carstens #define CACHE_MAX_LEVEL 8 71*881730adSHeiko Carstens 72*881730adSHeiko Carstens union cache_topology { 73*881730adSHeiko Carstens struct cache_info ci[CACHE_MAX_LEVEL]; 74*881730adSHeiko Carstens unsigned long long raw; 75*881730adSHeiko Carstens }; 76*881730adSHeiko Carstens 77*881730adSHeiko Carstens static const char * const cache_type_string[] = { 78*881730adSHeiko Carstens "Data", 79*881730adSHeiko Carstens "Instruction", 80*881730adSHeiko Carstens "Unified", 81*881730adSHeiko Carstens }; 82*881730adSHeiko Carstens 83*881730adSHeiko Carstens static struct cache_dir *cache_dir_cpu[NR_CPUS]; 84*881730adSHeiko Carstens static LIST_HEAD(cache_list); 85*881730adSHeiko Carstens 86*881730adSHeiko Carstens static inline unsigned long ecag(int ai, int li, int ti) 87*881730adSHeiko Carstens { 88*881730adSHeiko Carstens unsigned long cmd, val; 89*881730adSHeiko Carstens 90*881730adSHeiko Carstens cmd = ai << 4 | li << 1 | ti; 91*881730adSHeiko Carstens asm volatile(".insn rsy,0xeb000000004c,%0,0,0(%1)" /* ecag */ 92*881730adSHeiko Carstens : "=d" (val) : "a" (cmd)); 93*881730adSHeiko Carstens return val; 94*881730adSHeiko Carstens } 95*881730adSHeiko Carstens 96*881730adSHeiko Carstens static int __init cache_add(int level, int type) 97*881730adSHeiko Carstens { 98*881730adSHeiko Carstens struct cache *cache; 99*881730adSHeiko Carstens int ti; 100*881730adSHeiko Carstens 101*881730adSHeiko Carstens cache = kzalloc(sizeof(*cache), GFP_KERNEL); 102*881730adSHeiko Carstens if (!cache) 103*881730adSHeiko Carstens return -ENOMEM; 104*881730adSHeiko Carstens ti = type == CACHE_TYPE_DATA ? CACHE_TI_DATA : CACHE_TI_UNIFIED; 105*881730adSHeiko Carstens cache->size = ecag(EXTRACT_SIZE, level, ti); 106*881730adSHeiko Carstens cache->line_size = ecag(EXTRACT_LINE_SIZE, level, ti); 107*881730adSHeiko Carstens cache->associativity = ecag(EXTRACT_ASSOCIATIVITY, level, ti); 108*881730adSHeiko Carstens cache->nr_sets = cache->size / cache->associativity; 109*881730adSHeiko Carstens cache->nr_sets /= cache->line_size; 110*881730adSHeiko Carstens cache->level = level + 1; 111*881730adSHeiko Carstens cache->type = type; 112*881730adSHeiko Carstens list_add_tail(&cache->list, &cache_list); 113*881730adSHeiko Carstens return 0; 114*881730adSHeiko Carstens } 115*881730adSHeiko Carstens 116*881730adSHeiko Carstens static void __init cache_build_info(void) 117*881730adSHeiko Carstens { 118*881730adSHeiko Carstens struct cache *cache, *next; 119*881730adSHeiko Carstens union cache_topology ct; 120*881730adSHeiko Carstens int level, rc; 121*881730adSHeiko Carstens 122*881730adSHeiko Carstens ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0); 123*881730adSHeiko Carstens for (level = 0; level < CACHE_MAX_LEVEL; level++) { 124*881730adSHeiko Carstens switch (ct.ci[level].scope) { 125*881730adSHeiko Carstens case CACHE_SCOPE_NOTEXISTS: 126*881730adSHeiko Carstens case CACHE_SCOPE_RESERVED: 127*881730adSHeiko Carstens case CACHE_SCOPE_SHARED: 128*881730adSHeiko Carstens return; 129*881730adSHeiko Carstens case CACHE_SCOPE_PRIVATE: 130*881730adSHeiko Carstens break; 131*881730adSHeiko Carstens } 132*881730adSHeiko Carstens if (ct.ci[level].type == CACHE_TYPE_SEPARATE) { 133*881730adSHeiko Carstens rc = cache_add(level, CACHE_TYPE_DATA); 134*881730adSHeiko Carstens rc |= cache_add(level, CACHE_TYPE_INSTRUCTION); 135*881730adSHeiko Carstens } else { 136*881730adSHeiko Carstens rc = cache_add(level, ct.ci[level].type); 137*881730adSHeiko Carstens } 138*881730adSHeiko Carstens if (rc) 139*881730adSHeiko Carstens goto error; 140*881730adSHeiko Carstens } 141*881730adSHeiko Carstens return; 142*881730adSHeiko Carstens error: 143*881730adSHeiko Carstens list_for_each_entry_safe(cache, next, &cache_list, list) { 144*881730adSHeiko Carstens list_del(&cache->list); 145*881730adSHeiko Carstens kfree(cache); 146*881730adSHeiko Carstens } 147*881730adSHeiko Carstens } 148*881730adSHeiko Carstens 149*881730adSHeiko Carstens static struct cache_dir *__cpuinit cache_create_cache_dir(int cpu) 150*881730adSHeiko Carstens { 151*881730adSHeiko Carstens struct cache_dir *cache_dir; 152*881730adSHeiko Carstens struct kobject *kobj = NULL; 153*881730adSHeiko Carstens struct device *dev; 154*881730adSHeiko Carstens 155*881730adSHeiko Carstens dev = get_cpu_device(cpu); 156*881730adSHeiko Carstens if (!dev) 157*881730adSHeiko Carstens goto out; 158*881730adSHeiko Carstens kobj = kobject_create_and_add("cache", &dev->kobj); 159*881730adSHeiko Carstens if (!kobj) 160*881730adSHeiko Carstens goto out; 161*881730adSHeiko Carstens cache_dir = kzalloc(sizeof(*cache_dir), GFP_KERNEL); 162*881730adSHeiko Carstens if (!cache_dir) 163*881730adSHeiko Carstens goto out; 164*881730adSHeiko Carstens cache_dir->kobj = kobj; 165*881730adSHeiko Carstens cache_dir_cpu[cpu] = cache_dir; 166*881730adSHeiko Carstens return cache_dir; 167*881730adSHeiko Carstens out: 168*881730adSHeiko Carstens kobject_put(kobj); 169*881730adSHeiko Carstens return NULL; 170*881730adSHeiko Carstens } 171*881730adSHeiko Carstens 172*881730adSHeiko Carstens static struct cache_index_dir *kobj_to_cache_index_dir(struct kobject *kobj) 173*881730adSHeiko Carstens { 174*881730adSHeiko Carstens return container_of(kobj, struct cache_index_dir, kobj); 175*881730adSHeiko Carstens } 176*881730adSHeiko Carstens 177*881730adSHeiko Carstens static void cache_index_release(struct kobject *kobj) 178*881730adSHeiko Carstens { 179*881730adSHeiko Carstens struct cache_index_dir *index; 180*881730adSHeiko Carstens 181*881730adSHeiko Carstens index = kobj_to_cache_index_dir(kobj); 182*881730adSHeiko Carstens kfree(index); 183*881730adSHeiko Carstens } 184*881730adSHeiko Carstens 185*881730adSHeiko Carstens static ssize_t cache_index_show(struct kobject *kobj, 186*881730adSHeiko Carstens struct attribute *attr, char *buf) 187*881730adSHeiko Carstens { 188*881730adSHeiko Carstens struct kobj_attribute *kobj_attr; 189*881730adSHeiko Carstens 190*881730adSHeiko Carstens kobj_attr = container_of(attr, struct kobj_attribute, attr); 191*881730adSHeiko Carstens return kobj_attr->show(kobj, kobj_attr, buf); 192*881730adSHeiko Carstens } 193*881730adSHeiko Carstens 194*881730adSHeiko Carstens #define DEFINE_CACHE_ATTR(_name, _format, _value) \ 195*881730adSHeiko Carstens static ssize_t cache_##_name##_show(struct kobject *kobj, \ 196*881730adSHeiko Carstens struct kobj_attribute *attr, \ 197*881730adSHeiko Carstens char *buf) \ 198*881730adSHeiko Carstens { \ 199*881730adSHeiko Carstens struct cache_index_dir *index; \ 200*881730adSHeiko Carstens \ 201*881730adSHeiko Carstens index = kobj_to_cache_index_dir(kobj); \ 202*881730adSHeiko Carstens return sprintf(buf, _format, _value); \ 203*881730adSHeiko Carstens } \ 204*881730adSHeiko Carstens static struct kobj_attribute cache_##_name##_attr = \ 205*881730adSHeiko Carstens __ATTR(_name, 0444, cache_##_name##_show, NULL); 206*881730adSHeiko Carstens 207*881730adSHeiko Carstens DEFINE_CACHE_ATTR(size, "%luK\n", index->cache->size >> 10); 208*881730adSHeiko Carstens DEFINE_CACHE_ATTR(coherency_line_size, "%u\n", index->cache->line_size); 209*881730adSHeiko Carstens DEFINE_CACHE_ATTR(number_of_sets, "%u\n", index->cache->nr_sets); 210*881730adSHeiko Carstens DEFINE_CACHE_ATTR(ways_of_associativity, "%u\n", index->cache->associativity); 211*881730adSHeiko Carstens DEFINE_CACHE_ATTR(type, "%s\n", cache_type_string[index->cache->type - 1]); 212*881730adSHeiko Carstens DEFINE_CACHE_ATTR(level, "%d\n", index->cache->level); 213*881730adSHeiko Carstens 214*881730adSHeiko Carstens static ssize_t shared_cpu_map_func(struct kobject *kobj, int type, char *buf) 215*881730adSHeiko Carstens { 216*881730adSHeiko Carstens struct cache_index_dir *index; 217*881730adSHeiko Carstens int len; 218*881730adSHeiko Carstens 219*881730adSHeiko Carstens index = kobj_to_cache_index_dir(kobj); 220*881730adSHeiko Carstens len = type ? 221*881730adSHeiko Carstens cpulist_scnprintf(buf, PAGE_SIZE - 2, cpumask_of(index->cpu)) : 222*881730adSHeiko Carstens cpumask_scnprintf(buf, PAGE_SIZE - 2, cpumask_of(index->cpu)); 223*881730adSHeiko Carstens len += sprintf(&buf[len], "\n"); 224*881730adSHeiko Carstens return len; 225*881730adSHeiko Carstens } 226*881730adSHeiko Carstens 227*881730adSHeiko Carstens static ssize_t shared_cpu_map_show(struct kobject *kobj, 228*881730adSHeiko Carstens struct kobj_attribute *attr, char *buf) 229*881730adSHeiko Carstens { 230*881730adSHeiko Carstens return shared_cpu_map_func(kobj, 0, buf); 231*881730adSHeiko Carstens } 232*881730adSHeiko Carstens static struct kobj_attribute cache_shared_cpu_map_attr = 233*881730adSHeiko Carstens __ATTR(shared_cpu_map, 0444, shared_cpu_map_show, NULL); 234*881730adSHeiko Carstens 235*881730adSHeiko Carstens static ssize_t shared_cpu_list_show(struct kobject *kobj, 236*881730adSHeiko Carstens struct kobj_attribute *attr, char *buf) 237*881730adSHeiko Carstens { 238*881730adSHeiko Carstens return shared_cpu_map_func(kobj, 1, buf); 239*881730adSHeiko Carstens } 240*881730adSHeiko Carstens static struct kobj_attribute cache_shared_cpu_list_attr = 241*881730adSHeiko Carstens __ATTR(shared_cpu_list, 0444, shared_cpu_list_show, NULL); 242*881730adSHeiko Carstens 243*881730adSHeiko Carstens static struct attribute *cache_index_default_attrs[] = { 244*881730adSHeiko Carstens &cache_type_attr.attr, 245*881730adSHeiko Carstens &cache_size_attr.attr, 246*881730adSHeiko Carstens &cache_number_of_sets_attr.attr, 247*881730adSHeiko Carstens &cache_ways_of_associativity_attr.attr, 248*881730adSHeiko Carstens &cache_level_attr.attr, 249*881730adSHeiko Carstens &cache_coherency_line_size_attr.attr, 250*881730adSHeiko Carstens &cache_shared_cpu_map_attr.attr, 251*881730adSHeiko Carstens &cache_shared_cpu_list_attr.attr, 252*881730adSHeiko Carstens NULL, 253*881730adSHeiko Carstens }; 254*881730adSHeiko Carstens 255*881730adSHeiko Carstens static const struct sysfs_ops cache_index_ops = { 256*881730adSHeiko Carstens .show = cache_index_show, 257*881730adSHeiko Carstens }; 258*881730adSHeiko Carstens 259*881730adSHeiko Carstens static struct kobj_type cache_index_type = { 260*881730adSHeiko Carstens .sysfs_ops = &cache_index_ops, 261*881730adSHeiko Carstens .release = cache_index_release, 262*881730adSHeiko Carstens .default_attrs = cache_index_default_attrs, 263*881730adSHeiko Carstens }; 264*881730adSHeiko Carstens 265*881730adSHeiko Carstens static int __cpuinit cache_create_index_dir(struct cache_dir *cache_dir, 266*881730adSHeiko Carstens struct cache *cache, int index, 267*881730adSHeiko Carstens int cpu) 268*881730adSHeiko Carstens { 269*881730adSHeiko Carstens struct cache_index_dir *index_dir; 270*881730adSHeiko Carstens int rc; 271*881730adSHeiko Carstens 272*881730adSHeiko Carstens index_dir = kzalloc(sizeof(*index_dir), GFP_KERNEL); 273*881730adSHeiko Carstens if (!index_dir) 274*881730adSHeiko Carstens return -ENOMEM; 275*881730adSHeiko Carstens index_dir->cache = cache; 276*881730adSHeiko Carstens index_dir->cpu = cpu; 277*881730adSHeiko Carstens rc = kobject_init_and_add(&index_dir->kobj, &cache_index_type, 278*881730adSHeiko Carstens cache_dir->kobj, "index%d", index); 279*881730adSHeiko Carstens if (rc) 280*881730adSHeiko Carstens goto out; 281*881730adSHeiko Carstens index_dir->next = cache_dir->index; 282*881730adSHeiko Carstens cache_dir->index = index_dir; 283*881730adSHeiko Carstens return 0; 284*881730adSHeiko Carstens out: 285*881730adSHeiko Carstens kfree(index_dir); 286*881730adSHeiko Carstens return rc; 287*881730adSHeiko Carstens } 288*881730adSHeiko Carstens 289*881730adSHeiko Carstens static int __cpuinit cache_add_cpu(int cpu) 290*881730adSHeiko Carstens { 291*881730adSHeiko Carstens struct cache_dir *cache_dir; 292*881730adSHeiko Carstens struct cache *cache; 293*881730adSHeiko Carstens int rc, index = 0; 294*881730adSHeiko Carstens 295*881730adSHeiko Carstens if (list_empty(&cache_list)) 296*881730adSHeiko Carstens return 0; 297*881730adSHeiko Carstens cache_dir = cache_create_cache_dir(cpu); 298*881730adSHeiko Carstens if (!cache_dir) 299*881730adSHeiko Carstens return -ENOMEM; 300*881730adSHeiko Carstens list_for_each_entry(cache, &cache_list, list) { 301*881730adSHeiko Carstens rc = cache_create_index_dir(cache_dir, cache, index, cpu); 302*881730adSHeiko Carstens if (rc) 303*881730adSHeiko Carstens return rc; 304*881730adSHeiko Carstens index++; 305*881730adSHeiko Carstens } 306*881730adSHeiko Carstens return 0; 307*881730adSHeiko Carstens } 308*881730adSHeiko Carstens 309*881730adSHeiko Carstens static void __cpuinit cache_remove_cpu(int cpu) 310*881730adSHeiko Carstens { 311*881730adSHeiko Carstens struct cache_index_dir *index, *next; 312*881730adSHeiko Carstens struct cache_dir *cache_dir; 313*881730adSHeiko Carstens 314*881730adSHeiko Carstens cache_dir = cache_dir_cpu[cpu]; 315*881730adSHeiko Carstens if (!cache_dir) 316*881730adSHeiko Carstens return; 317*881730adSHeiko Carstens index = cache_dir->index; 318*881730adSHeiko Carstens while (index) { 319*881730adSHeiko Carstens next = index->next; 320*881730adSHeiko Carstens kobject_put(&index->kobj); 321*881730adSHeiko Carstens index = next; 322*881730adSHeiko Carstens } 323*881730adSHeiko Carstens kobject_put(cache_dir->kobj); 324*881730adSHeiko Carstens kfree(cache_dir); 325*881730adSHeiko Carstens cache_dir_cpu[cpu] = NULL; 326*881730adSHeiko Carstens } 327*881730adSHeiko Carstens 328*881730adSHeiko Carstens static int __cpuinit cache_hotplug(struct notifier_block *nfb, 329*881730adSHeiko Carstens unsigned long action, void *hcpu) 330*881730adSHeiko Carstens { 331*881730adSHeiko Carstens int cpu = (long)hcpu; 332*881730adSHeiko Carstens int rc = 0; 333*881730adSHeiko Carstens 334*881730adSHeiko Carstens switch (action & ~CPU_TASKS_FROZEN) { 335*881730adSHeiko Carstens case CPU_ONLINE: 336*881730adSHeiko Carstens rc = cache_add_cpu(cpu); 337*881730adSHeiko Carstens if (rc) 338*881730adSHeiko Carstens cache_remove_cpu(cpu); 339*881730adSHeiko Carstens break; 340*881730adSHeiko Carstens case CPU_DEAD: 341*881730adSHeiko Carstens cache_remove_cpu(cpu); 342*881730adSHeiko Carstens break; 343*881730adSHeiko Carstens } 344*881730adSHeiko Carstens return rc ? NOTIFY_BAD : NOTIFY_OK; 345*881730adSHeiko Carstens } 346*881730adSHeiko Carstens 347*881730adSHeiko Carstens static int __init cache_init(void) 348*881730adSHeiko Carstens { 349*881730adSHeiko Carstens int cpu; 350*881730adSHeiko Carstens 351*881730adSHeiko Carstens if (!test_facility(34)) 352*881730adSHeiko Carstens return 0; 353*881730adSHeiko Carstens cache_build_info(); 354*881730adSHeiko Carstens for_each_online_cpu(cpu) 355*881730adSHeiko Carstens cache_add_cpu(cpu); 356*881730adSHeiko Carstens hotcpu_notifier(cache_hotplug, 0); 357*881730adSHeiko Carstens return 0; 358*881730adSHeiko Carstens } 359*881730adSHeiko Carstens device_initcall(cache_init); 360