xref: /linux/drivers/acpi/numa/hmat.c (revision 1947b92464c3268381604bbe2ac977a3fd78192f)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2019, Intel Corporation.
4  *
5  * Heterogeneous Memory Attributes Table (HMAT) representation
6  *
7  * This program parses and reports the platform's HMAT tables, and registers
8  * the applicable attributes with the node's interfaces.
9  */
10 
11 #define pr_fmt(fmt) "acpi/hmat: " fmt
12 
13 #include <linux/acpi.h>
14 #include <linux/bitops.h>
15 #include <linux/device.h>
16 #include <linux/init.h>
17 #include <linux/list.h>
18 #include <linux/mm.h>
19 #include <linux/platform_device.h>
20 #include <linux/list_sort.h>
21 #include <linux/memregion.h>
22 #include <linux/memory.h>
23 #include <linux/mutex.h>
24 #include <linux/node.h>
25 #include <linux/sysfs.h>
26 #include <linux/dax.h>
27 #include <linux/memory-tiers.h>
28 
29 static u8 hmat_revision;
30 static int hmat_disable __initdata;
31 
32 void __init disable_hmat(void)
33 {
34 	hmat_disable = 1;
35 }
36 
37 static LIST_HEAD(targets);
38 static LIST_HEAD(initiators);
39 static LIST_HEAD(localities);
40 
41 static DEFINE_MUTEX(target_lock);
42 
43 /*
44  * The defined enum order is used to prioritize attributes to break ties when
45  * selecting the best performing node.
46  */
47 enum locality_types {
48 	WRITE_LATENCY,
49 	READ_LATENCY,
50 	WRITE_BANDWIDTH,
51 	READ_BANDWIDTH,
52 };
53 
54 static struct memory_locality *localities_types[4];
55 
56 struct target_cache {
57 	struct list_head node;
58 	struct node_cache_attrs cache_attrs;
59 };
60 
61 enum {
62 	NODE_ACCESS_CLASS_0 = 0,
63 	NODE_ACCESS_CLASS_1,
64 	NODE_ACCESS_CLASS_GENPORT_SINK,
65 	NODE_ACCESS_CLASS_MAX,
66 };
67 
68 struct memory_target {
69 	struct list_head node;
70 	unsigned int memory_pxm;
71 	unsigned int processor_pxm;
72 	struct resource memregions;
73 	struct access_coordinate coord[NODE_ACCESS_CLASS_MAX];
74 	struct list_head caches;
75 	struct node_cache_attrs cache_attrs;
76 	u8 gen_port_device_handle[ACPI_SRAT_DEVICE_HANDLE_SIZE];
77 	bool registered;
78 };
79 
80 struct memory_initiator {
81 	struct list_head node;
82 	unsigned int processor_pxm;
83 	bool has_cpu;
84 };
85 
86 struct memory_locality {
87 	struct list_head node;
88 	struct acpi_hmat_locality *hmat_loc;
89 };
90 
91 static struct memory_initiator *find_mem_initiator(unsigned int cpu_pxm)
92 {
93 	struct memory_initiator *initiator;
94 
95 	list_for_each_entry(initiator, &initiators, node)
96 		if (initiator->processor_pxm == cpu_pxm)
97 			return initiator;
98 	return NULL;
99 }
100 
101 static struct memory_target *find_mem_target(unsigned int mem_pxm)
102 {
103 	struct memory_target *target;
104 
105 	list_for_each_entry(target, &targets, node)
106 		if (target->memory_pxm == mem_pxm)
107 			return target;
108 	return NULL;
109 }
110 
111 static struct memory_target *acpi_find_genport_target(u32 uid)
112 {
113 	struct memory_target *target;
114 	u32 target_uid;
115 	u8 *uid_ptr;
116 
117 	list_for_each_entry(target, &targets, node) {
118 		uid_ptr = target->gen_port_device_handle + 8;
119 		target_uid = *(u32 *)uid_ptr;
120 		if (uid == target_uid)
121 			return target;
122 	}
123 
124 	return NULL;
125 }
126 
127 /**
128  * acpi_get_genport_coordinates - Retrieve the access coordinates for a generic port
129  * @uid: ACPI unique id
130  * @coord: The access coordinates written back out for the generic port
131  *
132  * Return: 0 on success. Errno on failure.
133  *
134  * Only supports device handles that are ACPI. Assume ACPI0016 HID for CXL.
135  */
136 int acpi_get_genport_coordinates(u32 uid,
137 				 struct access_coordinate *coord)
138 {
139 	struct memory_target *target;
140 
141 	guard(mutex)(&target_lock);
142 	target = acpi_find_genport_target(uid);
143 	if (!target)
144 		return -ENOENT;
145 
146 	*coord = target->coord[NODE_ACCESS_CLASS_GENPORT_SINK];
147 
148 	return 0;
149 }
150 EXPORT_SYMBOL_NS_GPL(acpi_get_genport_coordinates, CXL);
151 
152 static __init void alloc_memory_initiator(unsigned int cpu_pxm)
153 {
154 	struct memory_initiator *initiator;
155 
156 	if (pxm_to_node(cpu_pxm) == NUMA_NO_NODE)
157 		return;
158 
159 	initiator = find_mem_initiator(cpu_pxm);
160 	if (initiator)
161 		return;
162 
163 	initiator = kzalloc(sizeof(*initiator), GFP_KERNEL);
164 	if (!initiator)
165 		return;
166 
167 	initiator->processor_pxm = cpu_pxm;
168 	initiator->has_cpu = node_state(pxm_to_node(cpu_pxm), N_CPU);
169 	list_add_tail(&initiator->node, &initiators);
170 }
171 
172 static __init struct memory_target *alloc_target(unsigned int mem_pxm)
173 {
174 	struct memory_target *target;
175 
176 	target = find_mem_target(mem_pxm);
177 	if (!target) {
178 		target = kzalloc(sizeof(*target), GFP_KERNEL);
179 		if (!target)
180 			return NULL;
181 		target->memory_pxm = mem_pxm;
182 		target->processor_pxm = PXM_INVAL;
183 		target->memregions = (struct resource) {
184 			.name	= "ACPI mem",
185 			.start	= 0,
186 			.end	= -1,
187 			.flags	= IORESOURCE_MEM,
188 		};
189 		list_add_tail(&target->node, &targets);
190 		INIT_LIST_HEAD(&target->caches);
191 	}
192 
193 	return target;
194 }
195 
196 static __init void alloc_memory_target(unsigned int mem_pxm,
197 				       resource_size_t start,
198 				       resource_size_t len)
199 {
200 	struct memory_target *target;
201 
202 	target = alloc_target(mem_pxm);
203 	if (!target)
204 		return;
205 
206 	/*
207 	 * There are potentially multiple ranges per PXM, so record each
208 	 * in the per-target memregions resource tree.
209 	 */
210 	if (!__request_region(&target->memregions, start, len, "memory target",
211 				IORESOURCE_MEM))
212 		pr_warn("failed to reserve %#llx - %#llx in pxm: %d\n",
213 				start, start + len, mem_pxm);
214 }
215 
216 static __init void alloc_genport_target(unsigned int mem_pxm, u8 *handle)
217 {
218 	struct memory_target *target;
219 
220 	target = alloc_target(mem_pxm);
221 	if (!target)
222 		return;
223 
224 	memcpy(target->gen_port_device_handle, handle,
225 	       ACPI_SRAT_DEVICE_HANDLE_SIZE);
226 }
227 
228 static __init const char *hmat_data_type(u8 type)
229 {
230 	switch (type) {
231 	case ACPI_HMAT_ACCESS_LATENCY:
232 		return "Access Latency";
233 	case ACPI_HMAT_READ_LATENCY:
234 		return "Read Latency";
235 	case ACPI_HMAT_WRITE_LATENCY:
236 		return "Write Latency";
237 	case ACPI_HMAT_ACCESS_BANDWIDTH:
238 		return "Access Bandwidth";
239 	case ACPI_HMAT_READ_BANDWIDTH:
240 		return "Read Bandwidth";
241 	case ACPI_HMAT_WRITE_BANDWIDTH:
242 		return "Write Bandwidth";
243 	default:
244 		return "Reserved";
245 	}
246 }
247 
248 static __init const char *hmat_data_type_suffix(u8 type)
249 {
250 	switch (type) {
251 	case ACPI_HMAT_ACCESS_LATENCY:
252 	case ACPI_HMAT_READ_LATENCY:
253 	case ACPI_HMAT_WRITE_LATENCY:
254 		return " nsec";
255 	case ACPI_HMAT_ACCESS_BANDWIDTH:
256 	case ACPI_HMAT_READ_BANDWIDTH:
257 	case ACPI_HMAT_WRITE_BANDWIDTH:
258 		return " MB/s";
259 	default:
260 		return "";
261 	}
262 }
263 
264 static u32 hmat_normalize(u16 entry, u64 base, u8 type)
265 {
266 	u32 value;
267 
268 	/*
269 	 * Check for invalid and overflow values
270 	 */
271 	if (entry == 0xffff || !entry)
272 		return 0;
273 	else if (base > (UINT_MAX / (entry)))
274 		return 0;
275 
276 	/*
277 	 * Divide by the base unit for version 1, convert latency from
278 	 * picosenonds to nanoseconds if revision 2.
279 	 */
280 	value = entry * base;
281 	if (hmat_revision == 1) {
282 		if (value < 10)
283 			return 0;
284 		value = DIV_ROUND_UP(value, 10);
285 	} else if (hmat_revision == 2) {
286 		switch (type) {
287 		case ACPI_HMAT_ACCESS_LATENCY:
288 		case ACPI_HMAT_READ_LATENCY:
289 		case ACPI_HMAT_WRITE_LATENCY:
290 			value = DIV_ROUND_UP(value, 1000);
291 			break;
292 		default:
293 			break;
294 		}
295 	}
296 	return value;
297 }
298 
299 static void hmat_update_target_access(struct memory_target *target,
300 				      u8 type, u32 value, int access)
301 {
302 	switch (type) {
303 	case ACPI_HMAT_ACCESS_LATENCY:
304 		target->coord[access].read_latency = value;
305 		target->coord[access].write_latency = value;
306 		break;
307 	case ACPI_HMAT_READ_LATENCY:
308 		target->coord[access].read_latency = value;
309 		break;
310 	case ACPI_HMAT_WRITE_LATENCY:
311 		target->coord[access].write_latency = value;
312 		break;
313 	case ACPI_HMAT_ACCESS_BANDWIDTH:
314 		target->coord[access].read_bandwidth = value;
315 		target->coord[access].write_bandwidth = value;
316 		break;
317 	case ACPI_HMAT_READ_BANDWIDTH:
318 		target->coord[access].read_bandwidth = value;
319 		break;
320 	case ACPI_HMAT_WRITE_BANDWIDTH:
321 		target->coord[access].write_bandwidth = value;
322 		break;
323 	default:
324 		break;
325 	}
326 }
327 
328 static __init void hmat_add_locality(struct acpi_hmat_locality *hmat_loc)
329 {
330 	struct memory_locality *loc;
331 
332 	loc = kzalloc(sizeof(*loc), GFP_KERNEL);
333 	if (!loc) {
334 		pr_notice_once("Failed to allocate HMAT locality\n");
335 		return;
336 	}
337 
338 	loc->hmat_loc = hmat_loc;
339 	list_add_tail(&loc->node, &localities);
340 
341 	switch (hmat_loc->data_type) {
342 	case ACPI_HMAT_ACCESS_LATENCY:
343 		localities_types[READ_LATENCY] = loc;
344 		localities_types[WRITE_LATENCY] = loc;
345 		break;
346 	case ACPI_HMAT_READ_LATENCY:
347 		localities_types[READ_LATENCY] = loc;
348 		break;
349 	case ACPI_HMAT_WRITE_LATENCY:
350 		localities_types[WRITE_LATENCY] = loc;
351 		break;
352 	case ACPI_HMAT_ACCESS_BANDWIDTH:
353 		localities_types[READ_BANDWIDTH] = loc;
354 		localities_types[WRITE_BANDWIDTH] = loc;
355 		break;
356 	case ACPI_HMAT_READ_BANDWIDTH:
357 		localities_types[READ_BANDWIDTH] = loc;
358 		break;
359 	case ACPI_HMAT_WRITE_BANDWIDTH:
360 		localities_types[WRITE_BANDWIDTH] = loc;
361 		break;
362 	default:
363 		break;
364 	}
365 }
366 
367 static __init void hmat_update_target(unsigned int tgt_pxm, unsigned int init_pxm,
368 				      u8 mem_hier, u8 type, u32 value)
369 {
370 	struct memory_target *target = find_mem_target(tgt_pxm);
371 
372 	if (mem_hier != ACPI_HMAT_MEMORY)
373 		return;
374 
375 	if (target && target->processor_pxm == init_pxm) {
376 		hmat_update_target_access(target, type, value,
377 					  NODE_ACCESS_CLASS_0);
378 		/* If the node has a CPU, update access 1 */
379 		if (node_state(pxm_to_node(init_pxm), N_CPU))
380 			hmat_update_target_access(target, type, value,
381 						  NODE_ACCESS_CLASS_1);
382 	}
383 }
384 
385 static __init int hmat_parse_locality(union acpi_subtable_headers *header,
386 				      const unsigned long end)
387 {
388 	struct acpi_hmat_locality *hmat_loc = (void *)header;
389 	unsigned int init, targ, total_size, ipds, tpds;
390 	u32 *inits, *targs, value;
391 	u16 *entries;
392 	u8 type, mem_hier;
393 
394 	if (hmat_loc->header.length < sizeof(*hmat_loc)) {
395 		pr_notice("Unexpected locality header length: %u\n",
396 			 hmat_loc->header.length);
397 		return -EINVAL;
398 	}
399 
400 	type = hmat_loc->data_type;
401 	mem_hier = hmat_loc->flags & ACPI_HMAT_MEMORY_HIERARCHY;
402 	ipds = hmat_loc->number_of_initiator_Pds;
403 	tpds = hmat_loc->number_of_target_Pds;
404 	total_size = sizeof(*hmat_loc) + sizeof(*entries) * ipds * tpds +
405 		     sizeof(*inits) * ipds + sizeof(*targs) * tpds;
406 	if (hmat_loc->header.length < total_size) {
407 		pr_notice("Unexpected locality header length:%u, minimum required:%u\n",
408 			 hmat_loc->header.length, total_size);
409 		return -EINVAL;
410 	}
411 
412 	pr_info("Locality: Flags:%02x Type:%s Initiator Domains:%u Target Domains:%u Base:%lld\n",
413 		hmat_loc->flags, hmat_data_type(type), ipds, tpds,
414 		hmat_loc->entry_base_unit);
415 
416 	inits = (u32 *)(hmat_loc + 1);
417 	targs = inits + ipds;
418 	entries = (u16 *)(targs + tpds);
419 	for (init = 0; init < ipds; init++) {
420 		alloc_memory_initiator(inits[init]);
421 		for (targ = 0; targ < tpds; targ++) {
422 			value = hmat_normalize(entries[init * tpds + targ],
423 					       hmat_loc->entry_base_unit,
424 					       type);
425 			pr_info("  Initiator-Target[%u-%u]:%u%s\n",
426 				inits[init], targs[targ], value,
427 				hmat_data_type_suffix(type));
428 
429 			hmat_update_target(targs[targ], inits[init],
430 					   mem_hier, type, value);
431 		}
432 	}
433 
434 	if (mem_hier == ACPI_HMAT_MEMORY)
435 		hmat_add_locality(hmat_loc);
436 
437 	return 0;
438 }
439 
440 static __init int hmat_parse_cache(union acpi_subtable_headers *header,
441 				   const unsigned long end)
442 {
443 	struct acpi_hmat_cache *cache = (void *)header;
444 	struct memory_target *target;
445 	struct target_cache *tcache;
446 	u32 attrs;
447 
448 	if (cache->header.length < sizeof(*cache)) {
449 		pr_notice("Unexpected cache header length: %u\n",
450 			 cache->header.length);
451 		return -EINVAL;
452 	}
453 
454 	attrs = cache->cache_attributes;
455 	pr_info("Cache: Domain:%u Size:%llu Attrs:%08x SMBIOS Handles:%d\n",
456 		cache->memory_PD, cache->cache_size, attrs,
457 		cache->number_of_SMBIOShandles);
458 
459 	target = find_mem_target(cache->memory_PD);
460 	if (!target)
461 		return 0;
462 
463 	tcache = kzalloc(sizeof(*tcache), GFP_KERNEL);
464 	if (!tcache) {
465 		pr_notice_once("Failed to allocate HMAT cache info\n");
466 		return 0;
467 	}
468 
469 	tcache->cache_attrs.size = cache->cache_size;
470 	tcache->cache_attrs.level = (attrs & ACPI_HMAT_CACHE_LEVEL) >> 4;
471 	tcache->cache_attrs.line_size = (attrs & ACPI_HMAT_CACHE_LINE_SIZE) >> 16;
472 
473 	switch ((attrs & ACPI_HMAT_CACHE_ASSOCIATIVITY) >> 8) {
474 	case ACPI_HMAT_CA_DIRECT_MAPPED:
475 		tcache->cache_attrs.indexing = NODE_CACHE_DIRECT_MAP;
476 		break;
477 	case ACPI_HMAT_CA_COMPLEX_CACHE_INDEXING:
478 		tcache->cache_attrs.indexing = NODE_CACHE_INDEXED;
479 		break;
480 	case ACPI_HMAT_CA_NONE:
481 	default:
482 		tcache->cache_attrs.indexing = NODE_CACHE_OTHER;
483 		break;
484 	}
485 
486 	switch ((attrs & ACPI_HMAT_WRITE_POLICY) >> 12) {
487 	case ACPI_HMAT_CP_WB:
488 		tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_BACK;
489 		break;
490 	case ACPI_HMAT_CP_WT:
491 		tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_THROUGH;
492 		break;
493 	case ACPI_HMAT_CP_NONE:
494 	default:
495 		tcache->cache_attrs.write_policy = NODE_CACHE_WRITE_OTHER;
496 		break;
497 	}
498 	list_add_tail(&tcache->node, &target->caches);
499 
500 	return 0;
501 }
502 
503 static int __init hmat_parse_proximity_domain(union acpi_subtable_headers *header,
504 					      const unsigned long end)
505 {
506 	struct acpi_hmat_proximity_domain *p = (void *)header;
507 	struct memory_target *target = NULL;
508 
509 	if (p->header.length != sizeof(*p)) {
510 		pr_notice("Unexpected address range header length: %u\n",
511 			 p->header.length);
512 		return -EINVAL;
513 	}
514 
515 	if (hmat_revision == 1)
516 		pr_info("Memory (%#llx length %#llx) Flags:%04x Processor Domain:%u Memory Domain:%u\n",
517 			p->reserved3, p->reserved4, p->flags, p->processor_PD,
518 			p->memory_PD);
519 	else
520 		pr_info("Memory Flags:%04x Processor Domain:%u Memory Domain:%u\n",
521 			p->flags, p->processor_PD, p->memory_PD);
522 
523 	if ((hmat_revision == 1 && p->flags & ACPI_HMAT_MEMORY_PD_VALID) ||
524 	    hmat_revision > 1) {
525 		target = find_mem_target(p->memory_PD);
526 		if (!target) {
527 			pr_debug("Memory Domain missing from SRAT\n");
528 			return -EINVAL;
529 		}
530 	}
531 	if (target && p->flags & ACPI_HMAT_PROCESSOR_PD_VALID) {
532 		int p_node = pxm_to_node(p->processor_PD);
533 
534 		if (p_node == NUMA_NO_NODE) {
535 			pr_debug("Invalid Processor Domain\n");
536 			return -EINVAL;
537 		}
538 		target->processor_pxm = p->processor_PD;
539 	}
540 
541 	return 0;
542 }
543 
544 static int __init hmat_parse_subtable(union acpi_subtable_headers *header,
545 				      const unsigned long end)
546 {
547 	struct acpi_hmat_structure *hdr = (void *)header;
548 
549 	if (!hdr)
550 		return -EINVAL;
551 
552 	switch (hdr->type) {
553 	case ACPI_HMAT_TYPE_PROXIMITY:
554 		return hmat_parse_proximity_domain(header, end);
555 	case ACPI_HMAT_TYPE_LOCALITY:
556 		return hmat_parse_locality(header, end);
557 	case ACPI_HMAT_TYPE_CACHE:
558 		return hmat_parse_cache(header, end);
559 	default:
560 		return -EINVAL;
561 	}
562 }
563 
564 static __init int srat_parse_mem_affinity(union acpi_subtable_headers *header,
565 					  const unsigned long end)
566 {
567 	struct acpi_srat_mem_affinity *ma = (void *)header;
568 
569 	if (!ma)
570 		return -EINVAL;
571 	if (!(ma->flags & ACPI_SRAT_MEM_ENABLED))
572 		return 0;
573 	alloc_memory_target(ma->proximity_domain, ma->base_address, ma->length);
574 	return 0;
575 }
576 
577 static __init int srat_parse_genport_affinity(union acpi_subtable_headers *header,
578 					      const unsigned long end)
579 {
580 	struct acpi_srat_generic_affinity *ga = (void *)header;
581 
582 	if (!ga)
583 		return -EINVAL;
584 
585 	if (!(ga->flags & ACPI_SRAT_GENERIC_AFFINITY_ENABLED))
586 		return 0;
587 
588 	/* Skip PCI device_handle for now */
589 	if (ga->device_handle_type != 0)
590 		return 0;
591 
592 	alloc_genport_target(ga->proximity_domain,
593 			     (u8 *)ga->device_handle);
594 
595 	return 0;
596 }
597 
598 static u32 hmat_initiator_perf(struct memory_target *target,
599 			       struct memory_initiator *initiator,
600 			       struct acpi_hmat_locality *hmat_loc)
601 {
602 	unsigned int ipds, tpds, i, idx = 0, tdx = 0;
603 	u32 *inits, *targs;
604 	u16 *entries;
605 
606 	ipds = hmat_loc->number_of_initiator_Pds;
607 	tpds = hmat_loc->number_of_target_Pds;
608 	inits = (u32 *)(hmat_loc + 1);
609 	targs = inits + ipds;
610 	entries = (u16 *)(targs + tpds);
611 
612 	for (i = 0; i < ipds; i++) {
613 		if (inits[i] == initiator->processor_pxm) {
614 			idx = i;
615 			break;
616 		}
617 	}
618 
619 	if (i == ipds)
620 		return 0;
621 
622 	for (i = 0; i < tpds; i++) {
623 		if (targs[i] == target->memory_pxm) {
624 			tdx = i;
625 			break;
626 		}
627 	}
628 	if (i == tpds)
629 		return 0;
630 
631 	return hmat_normalize(entries[idx * tpds + tdx],
632 			      hmat_loc->entry_base_unit,
633 			      hmat_loc->data_type);
634 }
635 
636 static bool hmat_update_best(u8 type, u32 value, u32 *best)
637 {
638 	bool updated = false;
639 
640 	if (!value)
641 		return false;
642 
643 	switch (type) {
644 	case ACPI_HMAT_ACCESS_LATENCY:
645 	case ACPI_HMAT_READ_LATENCY:
646 	case ACPI_HMAT_WRITE_LATENCY:
647 		if (!*best || *best > value) {
648 			*best = value;
649 			updated = true;
650 		}
651 		break;
652 	case ACPI_HMAT_ACCESS_BANDWIDTH:
653 	case ACPI_HMAT_READ_BANDWIDTH:
654 	case ACPI_HMAT_WRITE_BANDWIDTH:
655 		if (!*best || *best < value) {
656 			*best = value;
657 			updated = true;
658 		}
659 		break;
660 	}
661 
662 	return updated;
663 }
664 
665 static int initiator_cmp(void *priv, const struct list_head *a,
666 			 const struct list_head *b)
667 {
668 	struct memory_initiator *ia;
669 	struct memory_initiator *ib;
670 
671 	ia = list_entry(a, struct memory_initiator, node);
672 	ib = list_entry(b, struct memory_initiator, node);
673 
674 	return ia->processor_pxm - ib->processor_pxm;
675 }
676 
677 static int initiators_to_nodemask(unsigned long *p_nodes)
678 {
679 	struct memory_initiator *initiator;
680 
681 	if (list_empty(&initiators))
682 		return -ENXIO;
683 
684 	list_for_each_entry(initiator, &initiators, node)
685 		set_bit(initiator->processor_pxm, p_nodes);
686 
687 	return 0;
688 }
689 
690 static void hmat_update_target_attrs(struct memory_target *target,
691 				     unsigned long *p_nodes, int access)
692 {
693 	struct memory_initiator *initiator;
694 	unsigned int cpu_nid;
695 	struct memory_locality *loc = NULL;
696 	u32 best = 0;
697 	int i;
698 
699 	/* Don't update for generic port if there's no device handle */
700 	if (access == NODE_ACCESS_CLASS_GENPORT_SINK &&
701 	    !(*(u16 *)target->gen_port_device_handle))
702 		return;
703 
704 	bitmap_zero(p_nodes, MAX_NUMNODES);
705 	/*
706 	 * If the Address Range Structure provides a local processor pxm, set
707 	 * only that one. Otherwise, find the best performance attributes and
708 	 * collect all initiators that match.
709 	 */
710 	if (target->processor_pxm != PXM_INVAL) {
711 		cpu_nid = pxm_to_node(target->processor_pxm);
712 		if (access == 0 || node_state(cpu_nid, N_CPU)) {
713 			set_bit(target->processor_pxm, p_nodes);
714 			return;
715 		}
716 	}
717 
718 	if (list_empty(&localities))
719 		return;
720 
721 	/*
722 	 * We need the initiator list sorted so we can use bitmap_clear for
723 	 * previously set initiators when we find a better memory accessor.
724 	 * We'll also use the sorting to prime the candidate nodes with known
725 	 * initiators.
726 	 */
727 	list_sort(NULL, &initiators, initiator_cmp);
728 	if (initiators_to_nodemask(p_nodes) < 0)
729 		return;
730 
731 	for (i = WRITE_LATENCY; i <= READ_BANDWIDTH; i++) {
732 		loc = localities_types[i];
733 		if (!loc)
734 			continue;
735 
736 		best = 0;
737 		list_for_each_entry(initiator, &initiators, node) {
738 			u32 value;
739 
740 			if (access == 1 && !initiator->has_cpu) {
741 				clear_bit(initiator->processor_pxm, p_nodes);
742 				continue;
743 			}
744 			if (!test_bit(initiator->processor_pxm, p_nodes))
745 				continue;
746 
747 			value = hmat_initiator_perf(target, initiator, loc->hmat_loc);
748 			if (hmat_update_best(loc->hmat_loc->data_type, value, &best))
749 				bitmap_clear(p_nodes, 0, initiator->processor_pxm);
750 			if (value != best)
751 				clear_bit(initiator->processor_pxm, p_nodes);
752 		}
753 		if (best)
754 			hmat_update_target_access(target, loc->hmat_loc->data_type, best, access);
755 	}
756 }
757 
758 static void __hmat_register_target_initiators(struct memory_target *target,
759 					      unsigned long *p_nodes,
760 					      int access)
761 {
762 	unsigned int mem_nid, cpu_nid;
763 	int i;
764 
765 	mem_nid = pxm_to_node(target->memory_pxm);
766 	hmat_update_target_attrs(target, p_nodes, access);
767 	for_each_set_bit(i, p_nodes, MAX_NUMNODES) {
768 		cpu_nid = pxm_to_node(i);
769 		register_memory_node_under_compute_node(mem_nid, cpu_nid, access);
770 	}
771 }
772 
773 static void hmat_register_generic_target_initiators(struct memory_target *target)
774 {
775 	static DECLARE_BITMAP(p_nodes, MAX_NUMNODES);
776 
777 	__hmat_register_target_initiators(target, p_nodes,
778 					  NODE_ACCESS_CLASS_GENPORT_SINK);
779 }
780 
781 static void hmat_register_target_initiators(struct memory_target *target)
782 {
783 	static DECLARE_BITMAP(p_nodes, MAX_NUMNODES);
784 
785 	__hmat_register_target_initiators(target, p_nodes, 0);
786 	__hmat_register_target_initiators(target, p_nodes, 1);
787 }
788 
789 static void hmat_register_target_cache(struct memory_target *target)
790 {
791 	unsigned mem_nid = pxm_to_node(target->memory_pxm);
792 	struct target_cache *tcache;
793 
794 	list_for_each_entry(tcache, &target->caches, node)
795 		node_add_cache(mem_nid, &tcache->cache_attrs);
796 }
797 
798 static void hmat_register_target_perf(struct memory_target *target, int access)
799 {
800 	unsigned mem_nid = pxm_to_node(target->memory_pxm);
801 	node_set_perf_attrs(mem_nid, &target->coord[access], access);
802 }
803 
804 static void hmat_register_target_devices(struct memory_target *target)
805 {
806 	struct resource *res;
807 
808 	/*
809 	 * Do not bother creating devices if no driver is available to
810 	 * consume them.
811 	 */
812 	if (!IS_ENABLED(CONFIG_DEV_DAX_HMEM))
813 		return;
814 
815 	for (res = target->memregions.child; res; res = res->sibling) {
816 		int target_nid = pxm_to_node(target->memory_pxm);
817 
818 		hmem_register_resource(target_nid, res);
819 	}
820 }
821 
822 static void hmat_register_target(struct memory_target *target)
823 {
824 	int nid = pxm_to_node(target->memory_pxm);
825 
826 	/*
827 	 * Devices may belong to either an offline or online
828 	 * node, so unconditionally add them.
829 	 */
830 	hmat_register_target_devices(target);
831 
832 	/*
833 	 * Register generic port perf numbers. The nid may not be
834 	 * initialized and is still NUMA_NO_NODE.
835 	 */
836 	mutex_lock(&target_lock);
837 	if (*(u16 *)target->gen_port_device_handle) {
838 		hmat_register_generic_target_initiators(target);
839 		target->registered = true;
840 	}
841 	mutex_unlock(&target_lock);
842 
843 	/*
844 	 * Skip offline nodes. This can happen when memory
845 	 * marked EFI_MEMORY_SP, "specific purpose", is applied
846 	 * to all the memory in a proximity domain leading to
847 	 * the node being marked offline / unplugged, or if
848 	 * memory-only "hotplug" node is offline.
849 	 */
850 	if (nid == NUMA_NO_NODE || !node_online(nid))
851 		return;
852 
853 	mutex_lock(&target_lock);
854 	if (!target->registered) {
855 		hmat_register_target_initiators(target);
856 		hmat_register_target_cache(target);
857 		hmat_register_target_perf(target, NODE_ACCESS_CLASS_0);
858 		hmat_register_target_perf(target, NODE_ACCESS_CLASS_1);
859 		target->registered = true;
860 	}
861 	mutex_unlock(&target_lock);
862 }
863 
864 static void hmat_register_targets(void)
865 {
866 	struct memory_target *target;
867 
868 	list_for_each_entry(target, &targets, node)
869 		hmat_register_target(target);
870 }
871 
872 static int hmat_callback(struct notifier_block *self,
873 			 unsigned long action, void *arg)
874 {
875 	struct memory_target *target;
876 	struct memory_notify *mnb = arg;
877 	int pxm, nid = mnb->status_change_nid;
878 
879 	if (nid == NUMA_NO_NODE || action != MEM_ONLINE)
880 		return NOTIFY_OK;
881 
882 	pxm = node_to_pxm(nid);
883 	target = find_mem_target(pxm);
884 	if (!target)
885 		return NOTIFY_OK;
886 
887 	hmat_register_target(target);
888 	return NOTIFY_OK;
889 }
890 
891 static int hmat_set_default_dram_perf(void)
892 {
893 	int rc;
894 	int nid, pxm;
895 	struct memory_target *target;
896 	struct access_coordinate *attrs;
897 
898 	if (!default_dram_type)
899 		return -EIO;
900 
901 	for_each_node_mask(nid, default_dram_type->nodes) {
902 		pxm = node_to_pxm(nid);
903 		target = find_mem_target(pxm);
904 		if (!target)
905 			continue;
906 		attrs = &target->coord[1];
907 		rc = mt_set_default_dram_perf(nid, attrs, "ACPI HMAT");
908 		if (rc)
909 			return rc;
910 	}
911 
912 	return 0;
913 }
914 
915 static int hmat_calculate_adistance(struct notifier_block *self,
916 				    unsigned long nid, void *data)
917 {
918 	static DECLARE_BITMAP(p_nodes, MAX_NUMNODES);
919 	struct memory_target *target;
920 	struct access_coordinate *perf;
921 	int *adist = data;
922 	int pxm;
923 
924 	pxm = node_to_pxm(nid);
925 	target = find_mem_target(pxm);
926 	if (!target)
927 		return NOTIFY_OK;
928 
929 	mutex_lock(&target_lock);
930 	hmat_update_target_attrs(target, p_nodes, 1);
931 	mutex_unlock(&target_lock);
932 
933 	perf = &target->coord[1];
934 
935 	if (mt_perf_to_adistance(perf, adist))
936 		return NOTIFY_OK;
937 
938 	return NOTIFY_STOP;
939 }
940 
941 static struct notifier_block hmat_adist_nb __meminitdata = {
942 	.notifier_call = hmat_calculate_adistance,
943 	.priority = 100,
944 };
945 
946 static __init void hmat_free_structures(void)
947 {
948 	struct memory_target *target, *tnext;
949 	struct memory_locality *loc, *lnext;
950 	struct memory_initiator *initiator, *inext;
951 	struct target_cache *tcache, *cnext;
952 
953 	list_for_each_entry_safe(target, tnext, &targets, node) {
954 		struct resource *res, *res_next;
955 
956 		list_for_each_entry_safe(tcache, cnext, &target->caches, node) {
957 			list_del(&tcache->node);
958 			kfree(tcache);
959 		}
960 
961 		list_del(&target->node);
962 		res = target->memregions.child;
963 		while (res) {
964 			res_next = res->sibling;
965 			__release_region(&target->memregions, res->start,
966 					resource_size(res));
967 			res = res_next;
968 		}
969 		kfree(target);
970 	}
971 
972 	list_for_each_entry_safe(initiator, inext, &initiators, node) {
973 		list_del(&initiator->node);
974 		kfree(initiator);
975 	}
976 
977 	list_for_each_entry_safe(loc, lnext, &localities, node) {
978 		list_del(&loc->node);
979 		kfree(loc);
980 	}
981 }
982 
983 static __init int hmat_init(void)
984 {
985 	struct acpi_table_header *tbl;
986 	enum acpi_hmat_type i;
987 	acpi_status status;
988 
989 	if (srat_disabled() || hmat_disable)
990 		return 0;
991 
992 	status = acpi_get_table(ACPI_SIG_SRAT, 0, &tbl);
993 	if (ACPI_FAILURE(status))
994 		return 0;
995 
996 	if (acpi_table_parse_entries(ACPI_SIG_SRAT,
997 				sizeof(struct acpi_table_srat),
998 				ACPI_SRAT_TYPE_MEMORY_AFFINITY,
999 				srat_parse_mem_affinity, 0) < 0)
1000 		goto out_put;
1001 
1002 	if (acpi_table_parse_entries(ACPI_SIG_SRAT,
1003 				     sizeof(struct acpi_table_srat),
1004 				     ACPI_SRAT_TYPE_GENERIC_PORT_AFFINITY,
1005 				     srat_parse_genport_affinity, 0) < 0)
1006 		goto out_put;
1007 
1008 	acpi_put_table(tbl);
1009 
1010 	status = acpi_get_table(ACPI_SIG_HMAT, 0, &tbl);
1011 	if (ACPI_FAILURE(status))
1012 		goto out_put;
1013 
1014 	hmat_revision = tbl->revision;
1015 	switch (hmat_revision) {
1016 	case 1:
1017 	case 2:
1018 		break;
1019 	default:
1020 		pr_notice("Ignoring: Unknown revision:%d\n", hmat_revision);
1021 		goto out_put;
1022 	}
1023 
1024 	for (i = ACPI_HMAT_TYPE_PROXIMITY; i < ACPI_HMAT_TYPE_RESERVED; i++) {
1025 		if (acpi_table_parse_entries(ACPI_SIG_HMAT,
1026 					     sizeof(struct acpi_table_hmat), i,
1027 					     hmat_parse_subtable, 0) < 0) {
1028 			pr_notice("Ignoring: Invalid table");
1029 			goto out_put;
1030 		}
1031 	}
1032 	hmat_register_targets();
1033 
1034 	/* Keep the table and structures if the notifier may use them */
1035 	if (hotplug_memory_notifier(hmat_callback, HMAT_CALLBACK_PRI))
1036 		goto out_put;
1037 
1038 	if (!hmat_set_default_dram_perf())
1039 		register_mt_adistance_algorithm(&hmat_adist_nb);
1040 
1041 	return 0;
1042 out_put:
1043 	hmat_free_structures();
1044 	acpi_put_table(tbl);
1045 	return 0;
1046 }
1047 subsys_initcall(hmat_init);
1048