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2bd00bcd JL |
1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* | |
3 | * pptt.c - parsing of Processor Properties Topology Table (PPTT) | |
4 | * | |
5 | * Copyright (C) 2018, ARM | |
6 | * | |
7 | * This file implements parsing of the Processor Properties Topology Table | |
8 | * which is optionally used to describe the processor and cache topology. | |
9 | * Due to the relative pointers used throughout the table, this doesn't | |
10 | * leverage the existing subtable parsing in the kernel. | |
11 | * | |
12 | * The PPTT structure is an inverted tree, with each node potentially | |
13 | * holding one or two inverted tree data structures describing | |
14 | * the caches available at that level. Each cache structure optionally | |
15 | * contains properties describing the cache at a given level which can be | |
16 | * used to override hardware probed values. | |
17 | */ | |
18 | #define pr_fmt(fmt) "ACPI PPTT: " fmt | |
19 | ||
20 | #include <linux/acpi.h> | |
21 | #include <linux/cacheinfo.h> | |
22 | #include <acpi/processor.h> | |
23 | ||
24 | static struct acpi_subtable_header *fetch_pptt_subtable(struct acpi_table_header *table_hdr, | |
25 | u32 pptt_ref) | |
26 | { | |
27 | struct acpi_subtable_header *entry; | |
28 | ||
29 | /* there isn't a subtable at reference 0 */ | |
30 | if (pptt_ref < sizeof(struct acpi_subtable_header)) | |
31 | return NULL; | |
32 | ||
33 | if (pptt_ref + sizeof(struct acpi_subtable_header) > table_hdr->length) | |
34 | return NULL; | |
35 | ||
36 | entry = ACPI_ADD_PTR(struct acpi_subtable_header, table_hdr, pptt_ref); | |
37 | ||
38 | if (entry->length == 0) | |
39 | return NULL; | |
40 | ||
41 | if (pptt_ref + entry->length > table_hdr->length) | |
42 | return NULL; | |
43 | ||
44 | return entry; | |
45 | } | |
46 | ||
47 | static struct acpi_pptt_processor *fetch_pptt_node(struct acpi_table_header *table_hdr, | |
48 | u32 pptt_ref) | |
49 | { | |
50 | return (struct acpi_pptt_processor *)fetch_pptt_subtable(table_hdr, pptt_ref); | |
51 | } | |
52 | ||
53 | static struct acpi_pptt_cache *fetch_pptt_cache(struct acpi_table_header *table_hdr, | |
54 | u32 pptt_ref) | |
55 | { | |
56 | return (struct acpi_pptt_cache *)fetch_pptt_subtable(table_hdr, pptt_ref); | |
57 | } | |
58 | ||
59 | static struct acpi_subtable_header *acpi_get_pptt_resource(struct acpi_table_header *table_hdr, | |
60 | struct acpi_pptt_processor *node, | |
61 | int resource) | |
62 | { | |
63 | u32 *ref; | |
64 | ||
65 | if (resource >= node->number_of_priv_resources) | |
66 | return NULL; | |
67 | ||
68 | ref = ACPI_ADD_PTR(u32, node, sizeof(struct acpi_pptt_processor)); | |
69 | ref += resource; | |
70 | ||
71 | return fetch_pptt_subtable(table_hdr, *ref); | |
72 | } | |
73 | ||
74 | static inline bool acpi_pptt_match_type(int table_type, int type) | |
75 | { | |
76 | return ((table_type & ACPI_PPTT_MASK_CACHE_TYPE) == type || | |
77 | table_type & ACPI_PPTT_CACHE_TYPE_UNIFIED & type); | |
78 | } | |
79 | ||
80 | /** | |
81 | * acpi_pptt_walk_cache() - Attempt to find the requested acpi_pptt_cache | |
82 | * @table_hdr: Pointer to the head of the PPTT table | |
83 | * @local_level: passed res reflects this cache level | |
84 | * @res: cache resource in the PPTT we want to walk | |
85 | * @found: returns a pointer to the requested level if found | |
86 | * @level: the requested cache level | |
87 | * @type: the requested cache type | |
88 | * | |
89 | * Attempt to find a given cache level, while counting the max number | |
90 | * of cache levels for the cache node. | |
91 | * | |
92 | * Given a pptt resource, verify that it is a cache node, then walk | |
93 | * down each level of caches, counting how many levels are found | |
94 | * as well as checking the cache type (icache, dcache, unified). If a | |
95 | * level & type match, then we set found, and continue the search. | |
96 | * Once the entire cache branch has been walked return its max | |
97 | * depth. | |
98 | * | |
99 | * Return: The cache structure and the level we terminated with. | |
100 | */ | |
101 | static int acpi_pptt_walk_cache(struct acpi_table_header *table_hdr, | |
102 | int local_level, | |
103 | struct acpi_subtable_header *res, | |
104 | struct acpi_pptt_cache **found, | |
105 | int level, int type) | |
106 | { | |
107 | struct acpi_pptt_cache *cache; | |
108 | ||
109 | if (res->type != ACPI_PPTT_TYPE_CACHE) | |
110 | return 0; | |
111 | ||
112 | cache = (struct acpi_pptt_cache *) res; | |
113 | while (cache) { | |
114 | local_level++; | |
115 | ||
116 | if (local_level == level && | |
117 | cache->flags & ACPI_PPTT_CACHE_TYPE_VALID && | |
118 | acpi_pptt_match_type(cache->attributes, type)) { | |
119 | if (*found != NULL && cache != *found) | |
120 | pr_warn("Found duplicate cache level/type unable to determine uniqueness\n"); | |
121 | ||
122 | pr_debug("Found cache @ level %d\n", level); | |
123 | *found = cache; | |
124 | /* | |
125 | * continue looking at this node's resource list | |
126 | * to verify that we don't find a duplicate | |
127 | * cache node. | |
128 | */ | |
129 | } | |
130 | cache = fetch_pptt_cache(table_hdr, cache->next_level_of_cache); | |
131 | } | |
132 | return local_level; | |
133 | } | |
134 | ||
135 | static struct acpi_pptt_cache *acpi_find_cache_level(struct acpi_table_header *table_hdr, | |
136 | struct acpi_pptt_processor *cpu_node, | |
137 | int *starting_level, int level, | |
138 | int type) | |
139 | { | |
140 | struct acpi_subtable_header *res; | |
141 | int number_of_levels = *starting_level; | |
142 | int resource = 0; | |
143 | struct acpi_pptt_cache *ret = NULL; | |
144 | int local_level; | |
145 | ||
146 | /* walk down from processor node */ | |
147 | while ((res = acpi_get_pptt_resource(table_hdr, cpu_node, resource))) { | |
148 | resource++; | |
149 | ||
150 | local_level = acpi_pptt_walk_cache(table_hdr, *starting_level, | |
151 | res, &ret, level, type); | |
152 | /* | |
153 | * we are looking for the max depth. Since its potentially | |
154 | * possible for a given node to have resources with differing | |
155 | * depths verify that the depth we have found is the largest. | |
156 | */ | |
157 | if (number_of_levels < local_level) | |
158 | number_of_levels = local_level; | |
159 | } | |
160 | if (number_of_levels > *starting_level) | |
161 | *starting_level = number_of_levels; | |
162 | ||
163 | return ret; | |
164 | } | |
165 | ||
166 | /** | |
167 | * acpi_count_levels() - Given a PPTT table, and a cpu node, count the caches | |
168 | * @table_hdr: Pointer to the head of the PPTT table | |
169 | * @cpu_node: processor node we wish to count caches for | |
170 | * | |
171 | * Given a processor node containing a processing unit, walk into it and count | |
172 | * how many levels exist solely for it, and then walk up each level until we hit | |
173 | * the root node (ignore the package level because it may be possible to have | |
174 | * caches that exist across packages). Count the number of cache levels that | |
175 | * exist at each level on the way up. | |
176 | * | |
177 | * Return: Total number of levels found. | |
178 | */ | |
179 | static int acpi_count_levels(struct acpi_table_header *table_hdr, | |
180 | struct acpi_pptt_processor *cpu_node) | |
181 | { | |
182 | int total_levels = 0; | |
183 | ||
184 | do { | |
185 | acpi_find_cache_level(table_hdr, cpu_node, &total_levels, 0, 0); | |
186 | cpu_node = fetch_pptt_node(table_hdr, cpu_node->parent); | |
187 | } while (cpu_node); | |
188 | ||
189 | return total_levels; | |
190 | } | |
191 | ||
192 | /** | |
193 | * acpi_pptt_leaf_node() - Given a processor node, determine if its a leaf | |
194 | * @table_hdr: Pointer to the head of the PPTT table | |
195 | * @node: passed node is checked to see if its a leaf | |
196 | * | |
197 | * Determine if the *node parameter is a leaf node by iterating the | |
198 | * PPTT table, looking for nodes which reference it. | |
199 | * | |
200 | * Return: 0 if we find a node referencing the passed node (or table error), | |
201 | * or 1 if we don't. | |
202 | */ | |
203 | static int acpi_pptt_leaf_node(struct acpi_table_header *table_hdr, | |
204 | struct acpi_pptt_processor *node) | |
205 | { | |
206 | struct acpi_subtable_header *entry; | |
207 | unsigned long table_end; | |
208 | u32 node_entry; | |
209 | struct acpi_pptt_processor *cpu_node; | |
210 | u32 proc_sz; | |
211 | ||
4909e6df JL |
212 | if (table_hdr->revision > 1) |
213 | return (node->flags & ACPI_PPTT_ACPI_LEAF_NODE); | |
214 | ||
2bd00bcd JL |
215 | table_end = (unsigned long)table_hdr + table_hdr->length; |
216 | node_entry = ACPI_PTR_DIFF(node, table_hdr); | |
217 | entry = ACPI_ADD_PTR(struct acpi_subtable_header, table_hdr, | |
218 | sizeof(struct acpi_table_pptt)); | |
219 | proc_sz = sizeof(struct acpi_pptt_processor *); | |
220 | ||
221 | while ((unsigned long)entry + proc_sz < table_end) { | |
222 | cpu_node = (struct acpi_pptt_processor *)entry; | |
223 | if (entry->type == ACPI_PPTT_TYPE_PROCESSOR && | |
224 | cpu_node->parent == node_entry) | |
225 | return 0; | |
226 | if (entry->length == 0) | |
227 | return 0; | |
228 | entry = ACPI_ADD_PTR(struct acpi_subtable_header, entry, | |
229 | entry->length); | |
230 | ||
231 | } | |
232 | return 1; | |
233 | } | |
234 | ||
235 | /** | |
236 | * acpi_find_processor_node() - Given a PPTT table find the requested processor | |
237 | * @table_hdr: Pointer to the head of the PPTT table | |
238 | * @acpi_cpu_id: cpu we are searching for | |
239 | * | |
240 | * Find the subtable entry describing the provided processor. | |
241 | * This is done by iterating the PPTT table looking for processor nodes | |
242 | * which have an acpi_processor_id that matches the acpi_cpu_id parameter | |
243 | * passed into the function. If we find a node that matches this criteria | |
244 | * we verify that its a leaf node in the topology rather than depending | |
245 | * on the valid flag, which doesn't need to be set for leaf nodes. | |
246 | * | |
247 | * Return: NULL, or the processors acpi_pptt_processor* | |
248 | */ | |
249 | static struct acpi_pptt_processor *acpi_find_processor_node(struct acpi_table_header *table_hdr, | |
250 | u32 acpi_cpu_id) | |
251 | { | |
252 | struct acpi_subtable_header *entry; | |
253 | unsigned long table_end; | |
254 | struct acpi_pptt_processor *cpu_node; | |
255 | u32 proc_sz; | |
256 | ||
257 | table_end = (unsigned long)table_hdr + table_hdr->length; | |
258 | entry = ACPI_ADD_PTR(struct acpi_subtable_header, table_hdr, | |
259 | sizeof(struct acpi_table_pptt)); | |
260 | proc_sz = sizeof(struct acpi_pptt_processor *); | |
261 | ||
262 | /* find the processor structure associated with this cpuid */ | |
263 | while ((unsigned long)entry + proc_sz < table_end) { | |
264 | cpu_node = (struct acpi_pptt_processor *)entry; | |
265 | ||
266 | if (entry->length == 0) { | |
267 | pr_warn("Invalid zero length subtable\n"); | |
268 | break; | |
269 | } | |
270 | if (entry->type == ACPI_PPTT_TYPE_PROCESSOR && | |
271 | acpi_cpu_id == cpu_node->acpi_processor_id && | |
272 | acpi_pptt_leaf_node(table_hdr, cpu_node)) { | |
273 | return (struct acpi_pptt_processor *)entry; | |
274 | } | |
275 | ||
276 | entry = ACPI_ADD_PTR(struct acpi_subtable_header, entry, | |
277 | entry->length); | |
278 | } | |
279 | ||
280 | return NULL; | |
281 | } | |
282 | ||
283 | static int acpi_find_cache_levels(struct acpi_table_header *table_hdr, | |
284 | u32 acpi_cpu_id) | |
285 | { | |
286 | int number_of_levels = 0; | |
287 | struct acpi_pptt_processor *cpu; | |
288 | ||
289 | cpu = acpi_find_processor_node(table_hdr, acpi_cpu_id); | |
290 | if (cpu) | |
291 | number_of_levels = acpi_count_levels(table_hdr, cpu); | |
292 | ||
293 | return number_of_levels; | |
294 | } | |
295 | ||
296 | static u8 acpi_cache_type(enum cache_type type) | |
297 | { | |
298 | switch (type) { | |
299 | case CACHE_TYPE_DATA: | |
300 | pr_debug("Looking for data cache\n"); | |
301 | return ACPI_PPTT_CACHE_TYPE_DATA; | |
302 | case CACHE_TYPE_INST: | |
303 | pr_debug("Looking for instruction cache\n"); | |
304 | return ACPI_PPTT_CACHE_TYPE_INSTR; | |
305 | default: | |
306 | case CACHE_TYPE_UNIFIED: | |
307 | pr_debug("Looking for unified cache\n"); | |
308 | /* | |
309 | * It is important that ACPI_PPTT_CACHE_TYPE_UNIFIED | |
310 | * contains the bit pattern that will match both | |
311 | * ACPI unified bit patterns because we use it later | |
312 | * to match both cases. | |
313 | */ | |
314 | return ACPI_PPTT_CACHE_TYPE_UNIFIED; | |
315 | } | |
316 | } | |
317 | ||
318 | static struct acpi_pptt_cache *acpi_find_cache_node(struct acpi_table_header *table_hdr, | |
319 | u32 acpi_cpu_id, | |
320 | enum cache_type type, | |
321 | unsigned int level, | |
322 | struct acpi_pptt_processor **node) | |
323 | { | |
324 | int total_levels = 0; | |
325 | struct acpi_pptt_cache *found = NULL; | |
326 | struct acpi_pptt_processor *cpu_node; | |
327 | u8 acpi_type = acpi_cache_type(type); | |
328 | ||
329 | pr_debug("Looking for CPU %d's level %d cache type %d\n", | |
330 | acpi_cpu_id, level, acpi_type); | |
331 | ||
332 | cpu_node = acpi_find_processor_node(table_hdr, acpi_cpu_id); | |
333 | ||
334 | while (cpu_node && !found) { | |
335 | found = acpi_find_cache_level(table_hdr, cpu_node, | |
336 | &total_levels, level, acpi_type); | |
337 | *node = cpu_node; | |
338 | cpu_node = fetch_pptt_node(table_hdr, cpu_node->parent); | |
339 | } | |
340 | ||
341 | return found; | |
342 | } | |
343 | ||
2bd00bcd JL |
344 | /** |
345 | * update_cache_properties() - Update cacheinfo for the given processor | |
346 | * @this_leaf: Kernel cache info structure being updated | |
347 | * @found_cache: The PPTT node describing this cache instance | |
348 | * @cpu_node: A unique reference to describe this cache instance | |
349 | * | |
350 | * The ACPI spec implies that the fields in the cache structures are used to | |
351 | * extend and correct the information probed from the hardware. Lets only | |
352 | * set fields that we determine are VALID. | |
353 | * | |
354 | * Return: nothing. Side effect of updating the global cacheinfo | |
355 | */ | |
356 | static void update_cache_properties(struct cacheinfo *this_leaf, | |
357 | struct acpi_pptt_cache *found_cache, | |
358 | struct acpi_pptt_processor *cpu_node) | |
359 | { | |
2bd00bcd | 360 | this_leaf->fw_token = cpu_node; |
59bbff37 | 361 | if (found_cache->flags & ACPI_PPTT_SIZE_PROPERTY_VALID) |
2bd00bcd | 362 | this_leaf->size = found_cache->size; |
59bbff37 | 363 | if (found_cache->flags & ACPI_PPTT_LINE_SIZE_VALID) |
2bd00bcd | 364 | this_leaf->coherency_line_size = found_cache->line_size; |
59bbff37 | 365 | if (found_cache->flags & ACPI_PPTT_NUMBER_OF_SETS_VALID) |
2bd00bcd | 366 | this_leaf->number_of_sets = found_cache->number_of_sets; |
59bbff37 | 367 | if (found_cache->flags & ACPI_PPTT_ASSOCIATIVITY_VALID) |
2bd00bcd | 368 | this_leaf->ways_of_associativity = found_cache->associativity; |
2bd00bcd JL |
369 | if (found_cache->flags & ACPI_PPTT_WRITE_POLICY_VALID) { |
370 | switch (found_cache->attributes & ACPI_PPTT_MASK_WRITE_POLICY) { | |
371 | case ACPI_PPTT_CACHE_POLICY_WT: | |
372 | this_leaf->attributes = CACHE_WRITE_THROUGH; | |
373 | break; | |
374 | case ACPI_PPTT_CACHE_POLICY_WB: | |
375 | this_leaf->attributes = CACHE_WRITE_BACK; | |
376 | break; | |
377 | } | |
378 | } | |
379 | if (found_cache->flags & ACPI_PPTT_ALLOCATION_TYPE_VALID) { | |
380 | switch (found_cache->attributes & ACPI_PPTT_MASK_ALLOCATION_TYPE) { | |
381 | case ACPI_PPTT_CACHE_READ_ALLOCATE: | |
382 | this_leaf->attributes |= CACHE_READ_ALLOCATE; | |
383 | break; | |
384 | case ACPI_PPTT_CACHE_WRITE_ALLOCATE: | |
385 | this_leaf->attributes |= CACHE_WRITE_ALLOCATE; | |
386 | break; | |
387 | case ACPI_PPTT_CACHE_RW_ALLOCATE: | |
388 | case ACPI_PPTT_CACHE_RW_ALLOCATE_ALT: | |
389 | this_leaf->attributes |= | |
390 | CACHE_READ_ALLOCATE | CACHE_WRITE_ALLOCATE; | |
391 | break; | |
392 | } | |
393 | } | |
394 | /* | |
59bbff37 JH |
395 | * If cache type is NOCACHE, then the cache hasn't been specified |
396 | * via other mechanisms. Update the type if a cache type has been | |
397 | * provided. | |
398 | * | |
399 | * Note, we assume such caches are unified based on conventional system | |
400 | * design and known examples. Significant work is required elsewhere to | |
401 | * fully support data/instruction only type caches which are only | |
402 | * specified in PPTT. | |
2bd00bcd JL |
403 | */ |
404 | if (this_leaf->type == CACHE_TYPE_NOCACHE && | |
59bbff37 | 405 | found_cache->flags & ACPI_PPTT_CACHE_TYPE_VALID) |
2bd00bcd JL |
406 | this_leaf->type = CACHE_TYPE_UNIFIED; |
407 | } | |
408 | ||
409 | static void cache_setup_acpi_cpu(struct acpi_table_header *table, | |
410 | unsigned int cpu) | |
411 | { | |
412 | struct acpi_pptt_cache *found_cache; | |
413 | struct cpu_cacheinfo *this_cpu_ci = get_cpu_cacheinfo(cpu); | |
414 | u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); | |
415 | struct cacheinfo *this_leaf; | |
416 | unsigned int index = 0; | |
417 | struct acpi_pptt_processor *cpu_node = NULL; | |
418 | ||
419 | while (index < get_cpu_cacheinfo(cpu)->num_leaves) { | |
420 | this_leaf = this_cpu_ci->info_list + index; | |
421 | found_cache = acpi_find_cache_node(table, acpi_cpu_id, | |
422 | this_leaf->type, | |
423 | this_leaf->level, | |
424 | &cpu_node); | |
425 | pr_debug("found = %p %p\n", found_cache, cpu_node); | |
426 | if (found_cache) | |
427 | update_cache_properties(this_leaf, | |
428 | found_cache, | |
429 | cpu_node); | |
430 | ||
431 | index++; | |
432 | } | |
433 | } | |
434 | ||
435 | /* Passing level values greater than this will result in search termination */ | |
436 | #define PPTT_ABORT_PACKAGE 0xFF | |
437 | ||
438 | static struct acpi_pptt_processor *acpi_find_processor_package_id(struct acpi_table_header *table_hdr, | |
439 | struct acpi_pptt_processor *cpu, | |
440 | int level, int flag) | |
441 | { | |
442 | struct acpi_pptt_processor *prev_node; | |
443 | ||
444 | while (cpu && level) { | |
445 | if (cpu->flags & flag) | |
446 | break; | |
447 | pr_debug("level %d\n", level); | |
448 | prev_node = fetch_pptt_node(table_hdr, cpu->parent); | |
449 | if (prev_node == NULL) | |
450 | break; | |
451 | cpu = prev_node; | |
452 | level--; | |
453 | } | |
454 | return cpu; | |
455 | } | |
456 | ||
6cafe700 JG |
457 | static void acpi_pptt_warn_missing(void) |
458 | { | |
459 | pr_warn_once("No PPTT table found, cpu and cache topology may be inaccurate\n"); | |
460 | } | |
461 | ||
2bd00bcd JL |
462 | /** |
463 | * topology_get_acpi_cpu_tag() - Find a unique topology value for a feature | |
464 | * @table: Pointer to the head of the PPTT table | |
465 | * @cpu: Kernel logical cpu number | |
466 | * @level: A level that terminates the search | |
467 | * @flag: A flag which terminates the search | |
468 | * | |
469 | * Get a unique value given a cpu, and a topology level, that can be | |
470 | * matched to determine which cpus share common topological features | |
471 | * at that level. | |
472 | * | |
473 | * Return: Unique value, or -ENOENT if unable to locate cpu | |
474 | */ | |
475 | static int topology_get_acpi_cpu_tag(struct acpi_table_header *table, | |
476 | unsigned int cpu, int level, int flag) | |
477 | { | |
478 | struct acpi_pptt_processor *cpu_node; | |
479 | u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); | |
480 | ||
481 | cpu_node = acpi_find_processor_node(table, acpi_cpu_id); | |
482 | if (cpu_node) { | |
483 | cpu_node = acpi_find_processor_package_id(table, cpu_node, | |
484 | level, flag); | |
30998033 SH |
485 | /* |
486 | * As per specification if the processor structure represents | |
487 | * an actual processor, then ACPI processor ID must be valid. | |
488 | * For processor containers ACPI_PPTT_ACPI_PROCESSOR_ID_VALID | |
489 | * should be set if the UID is valid | |
490 | */ | |
491 | if (level == 0 || | |
492 | cpu_node->flags & ACPI_PPTT_ACPI_PROCESSOR_ID_VALID) | |
2bd00bcd JL |
493 | return cpu_node->acpi_processor_id; |
494 | return ACPI_PTR_DIFF(cpu_node, table); | |
495 | } | |
496 | pr_warn_once("PPTT table found, but unable to locate core %d (%d)\n", | |
497 | cpu, acpi_cpu_id); | |
498 | return -ENOENT; | |
499 | } | |
500 | ||
501 | static int find_acpi_cpu_topology_tag(unsigned int cpu, int level, int flag) | |
502 | { | |
503 | struct acpi_table_header *table; | |
504 | acpi_status status; | |
505 | int retval; | |
506 | ||
507 | status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); | |
508 | if (ACPI_FAILURE(status)) { | |
6cafe700 | 509 | acpi_pptt_warn_missing(); |
2bd00bcd JL |
510 | return -ENOENT; |
511 | } | |
512 | retval = topology_get_acpi_cpu_tag(table, cpu, level, flag); | |
513 | pr_debug("Topology Setup ACPI cpu %d, level %d ret = %d\n", | |
514 | cpu, level, retval); | |
515 | acpi_put_table(table); | |
516 | ||
517 | return retval; | |
518 | } | |
519 | ||
520 | /** | |
521 | * acpi_find_last_cache_level() - Determines the number of cache levels for a PE | |
522 | * @cpu: Kernel logical cpu number | |
523 | * | |
524 | * Given a logical cpu number, returns the number of levels of cache represented | |
525 | * in the PPTT. Errors caused by lack of a PPTT table, or otherwise, return 0 | |
526 | * indicating we didn't find any cache levels. | |
527 | * | |
528 | * Return: Cache levels visible to this core. | |
529 | */ | |
530 | int acpi_find_last_cache_level(unsigned int cpu) | |
531 | { | |
532 | u32 acpi_cpu_id; | |
533 | struct acpi_table_header *table; | |
534 | int number_of_levels = 0; | |
535 | acpi_status status; | |
536 | ||
537 | pr_debug("Cache Setup find last level cpu=%d\n", cpu); | |
538 | ||
539 | acpi_cpu_id = get_acpi_id_for_cpu(cpu); | |
540 | status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); | |
541 | if (ACPI_FAILURE(status)) { | |
6cafe700 | 542 | acpi_pptt_warn_missing(); |
2bd00bcd JL |
543 | } else { |
544 | number_of_levels = acpi_find_cache_levels(table, acpi_cpu_id); | |
545 | acpi_put_table(table); | |
546 | } | |
547 | pr_debug("Cache Setup find last level level=%d\n", number_of_levels); | |
548 | ||
549 | return number_of_levels; | |
550 | } | |
551 | ||
552 | /** | |
553 | * cache_setup_acpi() - Override CPU cache topology with data from the PPTT | |
554 | * @cpu: Kernel logical cpu number | |
555 | * | |
556 | * Updates the global cache info provided by cpu_get_cacheinfo() | |
557 | * when there are valid properties in the acpi_pptt_cache nodes. A | |
558 | * successful parse may not result in any updates if none of the | |
559 | * cache levels have any valid flags set. Futher, a unique value is | |
560 | * associated with each known CPU cache entry. This unique value | |
561 | * can be used to determine whether caches are shared between cpus. | |
562 | * | |
563 | * Return: -ENOENT on failure to find table, or 0 on success | |
564 | */ | |
565 | int cache_setup_acpi(unsigned int cpu) | |
566 | { | |
567 | struct acpi_table_header *table; | |
568 | acpi_status status; | |
569 | ||
570 | pr_debug("Cache Setup ACPI cpu %d\n", cpu); | |
571 | ||
572 | status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); | |
573 | if (ACPI_FAILURE(status)) { | |
6cafe700 | 574 | acpi_pptt_warn_missing(); |
2bd00bcd JL |
575 | return -ENOENT; |
576 | } | |
577 | ||
578 | cache_setup_acpi_cpu(table, cpu); | |
579 | acpi_put_table(table); | |
580 | ||
581 | return status; | |
582 | } | |
583 | ||
584 | /** | |
585 | * find_acpi_cpu_topology() - Determine a unique topology value for a given cpu | |
586 | * @cpu: Kernel logical cpu number | |
587 | * @level: The topological level for which we would like a unique ID | |
588 | * | |
589 | * Determine a topology unique ID for each thread/core/cluster/mc_grouping | |
590 | * /socket/etc. This ID can then be used to group peers, which will have | |
591 | * matching ids. | |
592 | * | |
593 | * The search terminates when either the requested level is found or | |
594 | * we reach a root node. Levels beyond the termination point will return the | |
595 | * same unique ID. The unique id for level 0 is the acpi processor id. All | |
596 | * other levels beyond this use a generated value to uniquely identify | |
597 | * a topological feature. | |
598 | * | |
599 | * Return: -ENOENT if the PPTT doesn't exist, or the cpu cannot be found. | |
600 | * Otherwise returns a value which represents a unique topological feature. | |
601 | */ | |
602 | int find_acpi_cpu_topology(unsigned int cpu, int level) | |
603 | { | |
604 | return find_acpi_cpu_topology_tag(cpu, level, 0); | |
605 | } | |
606 | ||
607 | /** | |
608 | * find_acpi_cpu_cache_topology() - Determine a unique cache topology value | |
609 | * @cpu: Kernel logical cpu number | |
610 | * @level: The cache level for which we would like a unique ID | |
611 | * | |
612 | * Determine a unique ID for each unified cache in the system | |
613 | * | |
614 | * Return: -ENOENT if the PPTT doesn't exist, or the cpu cannot be found. | |
615 | * Otherwise returns a value which represents a unique topological feature. | |
616 | */ | |
617 | int find_acpi_cpu_cache_topology(unsigned int cpu, int level) | |
618 | { | |
619 | struct acpi_table_header *table; | |
620 | struct acpi_pptt_cache *found_cache; | |
621 | acpi_status status; | |
622 | u32 acpi_cpu_id = get_acpi_id_for_cpu(cpu); | |
623 | struct acpi_pptt_processor *cpu_node = NULL; | |
624 | int ret = -1; | |
625 | ||
626 | status = acpi_get_table(ACPI_SIG_PPTT, 0, &table); | |
627 | if (ACPI_FAILURE(status)) { | |
6cafe700 | 628 | acpi_pptt_warn_missing(); |
2bd00bcd JL |
629 | return -ENOENT; |
630 | } | |
631 | ||
632 | found_cache = acpi_find_cache_node(table, acpi_cpu_id, | |
633 | CACHE_TYPE_UNIFIED, | |
634 | level, | |
635 | &cpu_node); | |
636 | if (found_cache) | |
637 | ret = ACPI_PTR_DIFF(cpu_node, table); | |
638 | ||
639 | acpi_put_table(table); | |
640 | ||
641 | return ret; | |
642 | } | |
643 | ||
644 | ||
645 | /** | |
646 | * find_acpi_cpu_topology_package() - Determine a unique cpu package value | |
647 | * @cpu: Kernel logical cpu number | |
648 | * | |
649 | * Determine a topology unique package ID for the given cpu. | |
650 | * This ID can then be used to group peers, which will have matching ids. | |
651 | * | |
652 | * The search terminates when either a level is found with the PHYSICAL_PACKAGE | |
653 | * flag set or we reach a root node. | |
654 | * | |
655 | * Return: -ENOENT if the PPTT doesn't exist, or the cpu cannot be found. | |
656 | * Otherwise returns a value which represents the package for this cpu. | |
657 | */ | |
658 | int find_acpi_cpu_topology_package(unsigned int cpu) | |
659 | { | |
660 | return find_acpi_cpu_topology_tag(cpu, PPTT_ABORT_PACKAGE, | |
661 | ACPI_PPTT_PHYSICAL_PACKAGE); | |
662 | } |