| 1 | // SPDX-License-Identifier: GPL-2.0 |
| 2 | /* |
| 3 | * Extract CPU cache information and expose them via sysfs. |
| 4 | * |
| 5 | * Copyright IBM Corp. 2012 |
| 6 | */ |
| 7 | |
| 8 | #include <linux/seq_file.h> |
| 9 | #include <linux/cpu.h> |
| 10 | #include <linux/cacheinfo.h> |
| 11 | #include <asm/facility.h> |
| 12 | |
| 13 | enum { |
| 14 | CACHE_SCOPE_NOTEXISTS, |
| 15 | CACHE_SCOPE_PRIVATE, |
| 16 | CACHE_SCOPE_SHARED, |
| 17 | CACHE_SCOPE_RESERVED, |
| 18 | }; |
| 19 | |
| 20 | enum { |
| 21 | CTYPE_SEPARATE, |
| 22 | CTYPE_DATA, |
| 23 | CTYPE_INSTRUCTION, |
| 24 | CTYPE_UNIFIED, |
| 25 | }; |
| 26 | |
| 27 | enum { |
| 28 | EXTRACT_TOPOLOGY, |
| 29 | EXTRACT_LINE_SIZE, |
| 30 | EXTRACT_SIZE, |
| 31 | EXTRACT_ASSOCIATIVITY, |
| 32 | }; |
| 33 | |
| 34 | enum { |
| 35 | CACHE_TI_UNIFIED = 0, |
| 36 | CACHE_TI_DATA = 0, |
| 37 | CACHE_TI_INSTRUCTION, |
| 38 | }; |
| 39 | |
| 40 | struct cache_info { |
| 41 | unsigned char : 4; |
| 42 | unsigned char scope : 2; |
| 43 | unsigned char type : 2; |
| 44 | }; |
| 45 | |
| 46 | #define CACHE_MAX_LEVEL 8 |
| 47 | union cache_topology { |
| 48 | struct cache_info ci[CACHE_MAX_LEVEL]; |
| 49 | unsigned long raw; |
| 50 | }; |
| 51 | |
| 52 | static const char * const cache_type_string[] = { |
| 53 | "", |
| 54 | "Instruction", |
| 55 | "Data", |
| 56 | "", |
| 57 | "Unified", |
| 58 | }; |
| 59 | |
| 60 | static const enum cache_type cache_type_map[] = { |
| 61 | [CTYPE_SEPARATE] = CACHE_TYPE_SEPARATE, |
| 62 | [CTYPE_DATA] = CACHE_TYPE_DATA, |
| 63 | [CTYPE_INSTRUCTION] = CACHE_TYPE_INST, |
| 64 | [CTYPE_UNIFIED] = CACHE_TYPE_UNIFIED, |
| 65 | }; |
| 66 | |
| 67 | void show_cacheinfo(struct seq_file *m) |
| 68 | { |
| 69 | struct cpu_cacheinfo *this_cpu_ci; |
| 70 | struct cacheinfo *cache; |
| 71 | int idx; |
| 72 | |
| 73 | this_cpu_ci = get_cpu_cacheinfo(cpumask_any(cpu_online_mask)); |
| 74 | for (idx = 0; idx < this_cpu_ci->num_leaves; idx++) { |
| 75 | cache = this_cpu_ci->info_list + idx; |
| 76 | seq_printf(m, "cache%-11d: ", idx); |
| 77 | seq_printf(m, "level=%d ", cache->level); |
| 78 | seq_printf(m, "type=%s ", cache_type_string[cache->type]); |
| 79 | seq_printf(m, "scope=%s ", |
| 80 | cache->disable_sysfs ? "Shared" : "Private"); |
| 81 | seq_printf(m, "size=%dK ", cache->size >> 10); |
| 82 | seq_printf(m, "line_size=%u ", cache->coherency_line_size); |
| 83 | seq_printf(m, "associativity=%d", cache->ways_of_associativity); |
| 84 | seq_puts(m, "\n"); |
| 85 | } |
| 86 | } |
| 87 | |
| 88 | static inline enum cache_type get_cache_type(struct cache_info *ci, int level) |
| 89 | { |
| 90 | if (level >= CACHE_MAX_LEVEL) |
| 91 | return CACHE_TYPE_NOCACHE; |
| 92 | ci += level; |
| 93 | if (ci->scope != CACHE_SCOPE_SHARED && ci->scope != CACHE_SCOPE_PRIVATE) |
| 94 | return CACHE_TYPE_NOCACHE; |
| 95 | return cache_type_map[ci->type]; |
| 96 | } |
| 97 | |
| 98 | static inline unsigned long ecag(int ai, int li, int ti) |
| 99 | { |
| 100 | return __ecag(ECAG_CACHE_ATTRIBUTE, ai << 4 | li << 1 | ti); |
| 101 | } |
| 102 | |
| 103 | static void ci_leaf_init(struct cacheinfo *this_leaf, int private, |
| 104 | enum cache_type type, unsigned int level, int cpu) |
| 105 | { |
| 106 | int ti, num_sets; |
| 107 | |
| 108 | if (type == CACHE_TYPE_INST) |
| 109 | ti = CACHE_TI_INSTRUCTION; |
| 110 | else |
| 111 | ti = CACHE_TI_UNIFIED; |
| 112 | this_leaf->level = level + 1; |
| 113 | this_leaf->type = type; |
| 114 | this_leaf->coherency_line_size = ecag(EXTRACT_LINE_SIZE, level, ti); |
| 115 | this_leaf->ways_of_associativity = ecag(EXTRACT_ASSOCIATIVITY, level, ti); |
| 116 | this_leaf->size = ecag(EXTRACT_SIZE, level, ti); |
| 117 | num_sets = this_leaf->size / this_leaf->coherency_line_size; |
| 118 | num_sets /= this_leaf->ways_of_associativity; |
| 119 | this_leaf->number_of_sets = num_sets; |
| 120 | cpumask_set_cpu(cpu, &this_leaf->shared_cpu_map); |
| 121 | if (!private) |
| 122 | this_leaf->disable_sysfs = true; |
| 123 | } |
| 124 | |
| 125 | int init_cache_level(unsigned int cpu) |
| 126 | { |
| 127 | struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); |
| 128 | unsigned int level = 0, leaves = 0; |
| 129 | union cache_topology ct; |
| 130 | enum cache_type ctype; |
| 131 | |
| 132 | if (!this_cpu_ci) |
| 133 | return -EINVAL; |
| 134 | ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0); |
| 135 | do { |
| 136 | ctype = get_cache_type(&ct.ci[0], level); |
| 137 | if (ctype == CACHE_TYPE_NOCACHE) |
| 138 | break; |
| 139 | /* Separate instruction and data caches */ |
| 140 | leaves += (ctype == CACHE_TYPE_SEPARATE) ? 2 : 1; |
| 141 | } while (++level < CACHE_MAX_LEVEL); |
| 142 | this_cpu_ci->num_levels = level; |
| 143 | this_cpu_ci->num_leaves = leaves; |
| 144 | return 0; |
| 145 | } |
| 146 | |
| 147 | int populate_cache_leaves(unsigned int cpu) |
| 148 | { |
| 149 | struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); |
| 150 | struct cacheinfo *this_leaf = this_cpu_ci->info_list; |
| 151 | unsigned int level, idx, pvt; |
| 152 | union cache_topology ct; |
| 153 | enum cache_type ctype; |
| 154 | |
| 155 | ct.raw = ecag(EXTRACT_TOPOLOGY, 0, 0); |
| 156 | for (idx = 0, level = 0; level < this_cpu_ci->num_levels && |
| 157 | idx < this_cpu_ci->num_leaves; idx++, level++) { |
| 158 | if (!this_leaf) |
| 159 | return -EINVAL; |
| 160 | pvt = (ct.ci[level].scope == CACHE_SCOPE_PRIVATE) ? 1 : 0; |
| 161 | ctype = get_cache_type(&ct.ci[0], level); |
| 162 | if (ctype == CACHE_TYPE_SEPARATE) { |
| 163 | ci_leaf_init(this_leaf++, pvt, CACHE_TYPE_DATA, level, cpu); |
| 164 | ci_leaf_init(this_leaf++, pvt, CACHE_TYPE_INST, level, cpu); |
| 165 | } else { |
| 166 | ci_leaf_init(this_leaf++, pvt, ctype, level, cpu); |
| 167 | } |
| 168 | } |
| 169 | return 0; |
| 170 | } |