xref: /openbmc/linux/arch/sparc/kernel/mdesc.c (revision 96de2506)
1 // SPDX-License-Identifier: GPL-2.0
2 /* mdesc.c: Sun4V machine description handling.
3  *
4  * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
5  */
6 #include <linux/kernel.h>
7 #include <linux/types.h>
8 #include <linux/memblock.h>
9 #include <linux/log2.h>
10 #include <linux/list.h>
11 #include <linux/slab.h>
12 #include <linux/mm.h>
13 #include <linux/miscdevice.h>
14 #include <linux/bootmem.h>
15 #include <linux/export.h>
16 #include <linux/refcount.h>
17 
18 #include <asm/cpudata.h>
19 #include <asm/hypervisor.h>
20 #include <asm/mdesc.h>
21 #include <asm/prom.h>
22 #include <linux/uaccess.h>
23 #include <asm/oplib.h>
24 #include <asm/smp.h>
25 #include <asm/adi.h>
26 
27 /* Unlike the OBP device tree, the machine description is a full-on
28  * DAG.  An arbitrary number of ARCs are possible from one
29  * node to other nodes and thus we can't use the OBP device_node
30  * data structure to represent these nodes inside of the kernel.
31  *
32  * Actually, it isn't even a DAG, because there are back pointers
33  * which create cycles in the graph.
34  *
35  * mdesc_hdr and mdesc_elem describe the layout of the data structure
36  * we get from the Hypervisor.
37  */
38 struct mdesc_hdr {
39 	u32	version; /* Transport version */
40 	u32	node_sz; /* node block size */
41 	u32	name_sz; /* name block size */
42 	u32	data_sz; /* data block size */
43 } __attribute__((aligned(16)));
44 
45 struct mdesc_elem {
46 	u8	tag;
47 #define MD_LIST_END	0x00
48 #define MD_NODE		0x4e
49 #define MD_NODE_END	0x45
50 #define MD_NOOP		0x20
51 #define MD_PROP_ARC	0x61
52 #define MD_PROP_VAL	0x76
53 #define MD_PROP_STR	0x73
54 #define MD_PROP_DATA	0x64
55 	u8	name_len;
56 	u16	resv;
57 	u32	name_offset;
58 	union {
59 		struct {
60 			u32	data_len;
61 			u32	data_offset;
62 		} data;
63 		u64	val;
64 	} d;
65 };
66 
67 struct mdesc_mem_ops {
68 	struct mdesc_handle *(*alloc)(unsigned int mdesc_size);
69 	void (*free)(struct mdesc_handle *handle);
70 };
71 
72 struct mdesc_handle {
73 	struct list_head	list;
74 	struct mdesc_mem_ops	*mops;
75 	void			*self_base;
76 	refcount_t		refcnt;
77 	unsigned int		handle_size;
78 	struct mdesc_hdr	mdesc;
79 };
80 
81 typedef int (*mdesc_node_info_get_f)(struct mdesc_handle *, u64,
82 				     union md_node_info *);
83 typedef void (*mdesc_node_info_rel_f)(union md_node_info *);
84 typedef bool (*mdesc_node_match_f)(union md_node_info *, union md_node_info *);
85 
86 struct md_node_ops {
87 	char			*name;
88 	mdesc_node_info_get_f	get_info;
89 	mdesc_node_info_rel_f	rel_info;
90 	mdesc_node_match_f	node_match;
91 };
92 
93 static int get_vdev_port_node_info(struct mdesc_handle *md, u64 node,
94 				   union md_node_info *node_info);
95 static void rel_vdev_port_node_info(union md_node_info *node_info);
96 static bool vdev_port_node_match(union md_node_info *a_node_info,
97 				 union md_node_info *b_node_info);
98 
99 static int get_ds_port_node_info(struct mdesc_handle *md, u64 node,
100 				 union md_node_info *node_info);
101 static void rel_ds_port_node_info(union md_node_info *node_info);
102 static bool ds_port_node_match(union md_node_info *a_node_info,
103 			       union md_node_info *b_node_info);
104 
105 /* supported node types which can be registered */
106 static struct md_node_ops md_node_ops_table[] = {
107 	{"virtual-device-port", get_vdev_port_node_info,
108 	 rel_vdev_port_node_info, vdev_port_node_match},
109 	{"domain-services-port", get_ds_port_node_info,
110 	 rel_ds_port_node_info, ds_port_node_match},
111 	{NULL, NULL, NULL, NULL}
112 };
113 
114 static void mdesc_get_node_ops(const char *node_name,
115 			       mdesc_node_info_get_f *get_info_f,
116 			       mdesc_node_info_rel_f *rel_info_f,
117 			       mdesc_node_match_f *match_f)
118 {
119 	int i;
120 
121 	if (get_info_f)
122 		*get_info_f = NULL;
123 
124 	if (rel_info_f)
125 		*rel_info_f = NULL;
126 
127 	if (match_f)
128 		*match_f = NULL;
129 
130 	if (!node_name)
131 		return;
132 
133 	for (i = 0; md_node_ops_table[i].name != NULL; i++) {
134 		if (strcmp(md_node_ops_table[i].name, node_name) == 0) {
135 			if (get_info_f)
136 				*get_info_f = md_node_ops_table[i].get_info;
137 
138 			if (rel_info_f)
139 				*rel_info_f = md_node_ops_table[i].rel_info;
140 
141 			if (match_f)
142 				*match_f = md_node_ops_table[i].node_match;
143 
144 			break;
145 		}
146 	}
147 }
148 
149 static void mdesc_handle_init(struct mdesc_handle *hp,
150 			      unsigned int handle_size,
151 			      void *base)
152 {
153 	BUG_ON(((unsigned long)&hp->mdesc) & (16UL - 1));
154 
155 	memset(hp, 0, handle_size);
156 	INIT_LIST_HEAD(&hp->list);
157 	hp->self_base = base;
158 	refcount_set(&hp->refcnt, 1);
159 	hp->handle_size = handle_size;
160 }
161 
162 static struct mdesc_handle * __init mdesc_memblock_alloc(unsigned int mdesc_size)
163 {
164 	unsigned int handle_size, alloc_size;
165 	struct mdesc_handle *hp;
166 	unsigned long paddr;
167 
168 	handle_size = (sizeof(struct mdesc_handle) -
169 		       sizeof(struct mdesc_hdr) +
170 		       mdesc_size);
171 	alloc_size = PAGE_ALIGN(handle_size);
172 
173 	paddr = memblock_alloc(alloc_size, PAGE_SIZE);
174 
175 	hp = NULL;
176 	if (paddr) {
177 		hp = __va(paddr);
178 		mdesc_handle_init(hp, handle_size, hp);
179 	}
180 	return hp;
181 }
182 
183 static void __init mdesc_memblock_free(struct mdesc_handle *hp)
184 {
185 	unsigned int alloc_size;
186 	unsigned long start;
187 
188 	BUG_ON(refcount_read(&hp->refcnt) != 0);
189 	BUG_ON(!list_empty(&hp->list));
190 
191 	alloc_size = PAGE_ALIGN(hp->handle_size);
192 	start = __pa(hp);
193 	free_bootmem_late(start, alloc_size);
194 }
195 
196 static struct mdesc_mem_ops memblock_mdesc_ops = {
197 	.alloc = mdesc_memblock_alloc,
198 	.free  = mdesc_memblock_free,
199 };
200 
201 static struct mdesc_handle *mdesc_kmalloc(unsigned int mdesc_size)
202 {
203 	unsigned int handle_size;
204 	struct mdesc_handle *hp;
205 	unsigned long addr;
206 	void *base;
207 
208 	handle_size = (sizeof(struct mdesc_handle) -
209 		       sizeof(struct mdesc_hdr) +
210 		       mdesc_size);
211 	base = kmalloc(handle_size + 15, GFP_KERNEL | __GFP_RETRY_MAYFAIL);
212 	if (!base)
213 		return NULL;
214 
215 	addr = (unsigned long)base;
216 	addr = (addr + 15UL) & ~15UL;
217 	hp = (struct mdesc_handle *) addr;
218 
219 	mdesc_handle_init(hp, handle_size, base);
220 
221 	return hp;
222 }
223 
224 static void mdesc_kfree(struct mdesc_handle *hp)
225 {
226 	BUG_ON(refcount_read(&hp->refcnt) != 0);
227 	BUG_ON(!list_empty(&hp->list));
228 
229 	kfree(hp->self_base);
230 }
231 
232 static struct mdesc_mem_ops kmalloc_mdesc_memops = {
233 	.alloc = mdesc_kmalloc,
234 	.free  = mdesc_kfree,
235 };
236 
237 static struct mdesc_handle *mdesc_alloc(unsigned int mdesc_size,
238 					struct mdesc_mem_ops *mops)
239 {
240 	struct mdesc_handle *hp = mops->alloc(mdesc_size);
241 
242 	if (hp)
243 		hp->mops = mops;
244 
245 	return hp;
246 }
247 
248 static void mdesc_free(struct mdesc_handle *hp)
249 {
250 	hp->mops->free(hp);
251 }
252 
253 static struct mdesc_handle *cur_mdesc;
254 static LIST_HEAD(mdesc_zombie_list);
255 static DEFINE_SPINLOCK(mdesc_lock);
256 
257 struct mdesc_handle *mdesc_grab(void)
258 {
259 	struct mdesc_handle *hp;
260 	unsigned long flags;
261 
262 	spin_lock_irqsave(&mdesc_lock, flags);
263 	hp = cur_mdesc;
264 	if (hp)
265 		refcount_inc(&hp->refcnt);
266 	spin_unlock_irqrestore(&mdesc_lock, flags);
267 
268 	return hp;
269 }
270 EXPORT_SYMBOL(mdesc_grab);
271 
272 void mdesc_release(struct mdesc_handle *hp)
273 {
274 	unsigned long flags;
275 
276 	spin_lock_irqsave(&mdesc_lock, flags);
277 	if (refcount_dec_and_test(&hp->refcnt)) {
278 		list_del_init(&hp->list);
279 		hp->mops->free(hp);
280 	}
281 	spin_unlock_irqrestore(&mdesc_lock, flags);
282 }
283 EXPORT_SYMBOL(mdesc_release);
284 
285 static DEFINE_MUTEX(mdesc_mutex);
286 static struct mdesc_notifier_client *client_list;
287 
288 void mdesc_register_notifier(struct mdesc_notifier_client *client)
289 {
290 	bool supported = false;
291 	u64 node;
292 	int i;
293 
294 	mutex_lock(&mdesc_mutex);
295 
296 	/* check to see if the node is supported for registration */
297 	for (i = 0; md_node_ops_table[i].name != NULL; i++) {
298 		if (strcmp(md_node_ops_table[i].name, client->node_name) == 0) {
299 			supported = true;
300 			break;
301 		}
302 	}
303 
304 	if (!supported) {
305 		pr_err("MD: %s node not supported\n", client->node_name);
306 		mutex_unlock(&mdesc_mutex);
307 		return;
308 	}
309 
310 	client->next = client_list;
311 	client_list = client;
312 
313 	mdesc_for_each_node_by_name(cur_mdesc, node, client->node_name)
314 		client->add(cur_mdesc, node, client->node_name);
315 
316 	mutex_unlock(&mdesc_mutex);
317 }
318 
319 static const u64 *parent_cfg_handle(struct mdesc_handle *hp, u64 node)
320 {
321 	const u64 *id;
322 	u64 a;
323 
324 	id = NULL;
325 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
326 		u64 target;
327 
328 		target = mdesc_arc_target(hp, a);
329 		id = mdesc_get_property(hp, target,
330 					"cfg-handle", NULL);
331 		if (id)
332 			break;
333 	}
334 
335 	return id;
336 }
337 
338 static int get_vdev_port_node_info(struct mdesc_handle *md, u64 node,
339 				   union md_node_info *node_info)
340 {
341 	const u64 *parent_cfg_hdlp;
342 	const char *name;
343 	const u64 *idp;
344 
345 	/*
346 	 * Virtual device nodes are distinguished by:
347 	 * 1. "id" property
348 	 * 2. "name" property
349 	 * 3. parent node "cfg-handle" property
350 	 */
351 	idp = mdesc_get_property(md, node, "id", NULL);
352 	name = mdesc_get_property(md, node, "name", NULL);
353 	parent_cfg_hdlp = parent_cfg_handle(md, node);
354 
355 	if (!idp || !name || !parent_cfg_hdlp)
356 		return -1;
357 
358 	node_info->vdev_port.id = *idp;
359 	node_info->vdev_port.name = kstrdup_const(name, GFP_KERNEL);
360 	node_info->vdev_port.parent_cfg_hdl = *parent_cfg_hdlp;
361 
362 	return 0;
363 }
364 
365 static void rel_vdev_port_node_info(union md_node_info *node_info)
366 {
367 	if (node_info && node_info->vdev_port.name) {
368 		kfree_const(node_info->vdev_port.name);
369 		node_info->vdev_port.name = NULL;
370 	}
371 }
372 
373 static bool vdev_port_node_match(union md_node_info *a_node_info,
374 				 union md_node_info *b_node_info)
375 {
376 	if (a_node_info->vdev_port.id != b_node_info->vdev_port.id)
377 		return false;
378 
379 	if (a_node_info->vdev_port.parent_cfg_hdl !=
380 	    b_node_info->vdev_port.parent_cfg_hdl)
381 		return false;
382 
383 	if (strncmp(a_node_info->vdev_port.name,
384 		    b_node_info->vdev_port.name, MDESC_MAX_STR_LEN) != 0)
385 		return false;
386 
387 	return true;
388 }
389 
390 static int get_ds_port_node_info(struct mdesc_handle *md, u64 node,
391 				 union md_node_info *node_info)
392 {
393 	const u64 *idp;
394 
395 	/* DS port nodes use the "id" property to distinguish them */
396 	idp = mdesc_get_property(md, node, "id", NULL);
397 	if (!idp)
398 		return -1;
399 
400 	node_info->ds_port.id = *idp;
401 
402 	return 0;
403 }
404 
405 static void rel_ds_port_node_info(union md_node_info *node_info)
406 {
407 }
408 
409 static bool ds_port_node_match(union md_node_info *a_node_info,
410 			       union md_node_info *b_node_info)
411 {
412 	if (a_node_info->ds_port.id != b_node_info->ds_port.id)
413 		return false;
414 
415 	return true;
416 }
417 
418 /* Run 'func' on nodes which are in A but not in B.  */
419 static void invoke_on_missing(const char *name,
420 			      struct mdesc_handle *a,
421 			      struct mdesc_handle *b,
422 			      void (*func)(struct mdesc_handle *, u64,
423 					   const char *node_name))
424 {
425 	mdesc_node_info_get_f get_info_func;
426 	mdesc_node_info_rel_f rel_info_func;
427 	mdesc_node_match_f node_match_func;
428 	union md_node_info a_node_info;
429 	union md_node_info b_node_info;
430 	bool found;
431 	u64 a_node;
432 	u64 b_node;
433 	int rv;
434 
435 	/*
436 	 * Find the get_info, rel_info and node_match ops for the given
437 	 * node name
438 	 */
439 	mdesc_get_node_ops(name, &get_info_func, &rel_info_func,
440 			   &node_match_func);
441 
442 	/* If we didn't find a match, the node type is not supported */
443 	if (!get_info_func || !rel_info_func || !node_match_func) {
444 		pr_err("MD: %s node type is not supported\n", name);
445 		return;
446 	}
447 
448 	mdesc_for_each_node_by_name(a, a_node, name) {
449 		found = false;
450 
451 		rv = get_info_func(a, a_node, &a_node_info);
452 		if (rv != 0) {
453 			pr_err("MD: Cannot find 1 or more required match properties for %s node.\n",
454 			       name);
455 			continue;
456 		}
457 
458 		/* Check each node in B for node matching a_node */
459 		mdesc_for_each_node_by_name(b, b_node, name) {
460 			rv = get_info_func(b, b_node, &b_node_info);
461 			if (rv != 0)
462 				continue;
463 
464 			if (node_match_func(&a_node_info, &b_node_info)) {
465 				found = true;
466 				rel_info_func(&b_node_info);
467 				break;
468 			}
469 
470 			rel_info_func(&b_node_info);
471 		}
472 
473 		rel_info_func(&a_node_info);
474 
475 		if (!found)
476 			func(a, a_node, name);
477 	}
478 }
479 
480 static void notify_one(struct mdesc_notifier_client *p,
481 		       struct mdesc_handle *old_hp,
482 		       struct mdesc_handle *new_hp)
483 {
484 	invoke_on_missing(p->node_name, old_hp, new_hp, p->remove);
485 	invoke_on_missing(p->node_name, new_hp, old_hp, p->add);
486 }
487 
488 static void mdesc_notify_clients(struct mdesc_handle *old_hp,
489 				 struct mdesc_handle *new_hp)
490 {
491 	struct mdesc_notifier_client *p = client_list;
492 
493 	while (p) {
494 		notify_one(p, old_hp, new_hp);
495 		p = p->next;
496 	}
497 }
498 
499 void mdesc_update(void)
500 {
501 	unsigned long len, real_len, status;
502 	struct mdesc_handle *hp, *orig_hp;
503 	unsigned long flags;
504 
505 	mutex_lock(&mdesc_mutex);
506 
507 	(void) sun4v_mach_desc(0UL, 0UL, &len);
508 
509 	hp = mdesc_alloc(len, &kmalloc_mdesc_memops);
510 	if (!hp) {
511 		printk(KERN_ERR "MD: mdesc alloc fails\n");
512 		goto out;
513 	}
514 
515 	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
516 	if (status != HV_EOK || real_len > len) {
517 		printk(KERN_ERR "MD: mdesc reread fails with %lu\n",
518 		       status);
519 		refcount_dec(&hp->refcnt);
520 		mdesc_free(hp);
521 		goto out;
522 	}
523 
524 	spin_lock_irqsave(&mdesc_lock, flags);
525 	orig_hp = cur_mdesc;
526 	cur_mdesc = hp;
527 	spin_unlock_irqrestore(&mdesc_lock, flags);
528 
529 	mdesc_notify_clients(orig_hp, hp);
530 
531 	spin_lock_irqsave(&mdesc_lock, flags);
532 	if (refcount_dec_and_test(&orig_hp->refcnt))
533 		mdesc_free(orig_hp);
534 	else
535 		list_add(&orig_hp->list, &mdesc_zombie_list);
536 	spin_unlock_irqrestore(&mdesc_lock, flags);
537 
538 out:
539 	mutex_unlock(&mdesc_mutex);
540 }
541 
542 u64 mdesc_get_node(struct mdesc_handle *hp, const char *node_name,
543 		   union md_node_info *node_info)
544 {
545 	mdesc_node_info_get_f get_info_func;
546 	mdesc_node_info_rel_f rel_info_func;
547 	mdesc_node_match_f node_match_func;
548 	union md_node_info hp_node_info;
549 	u64 hp_node;
550 	int rv;
551 
552 	if (hp == NULL || node_name == NULL || node_info == NULL)
553 		return MDESC_NODE_NULL;
554 
555 	/* Find the ops for the given node name */
556 	mdesc_get_node_ops(node_name, &get_info_func, &rel_info_func,
557 			   &node_match_func);
558 
559 	/* If we didn't find ops for the given node name, it is not supported */
560 	if (!get_info_func || !rel_info_func || !node_match_func) {
561 		pr_err("MD: %s node is not supported\n", node_name);
562 		return -EINVAL;
563 	}
564 
565 	mdesc_for_each_node_by_name(hp, hp_node, node_name) {
566 		rv = get_info_func(hp, hp_node, &hp_node_info);
567 		if (rv != 0)
568 			continue;
569 
570 		if (node_match_func(node_info, &hp_node_info))
571 			break;
572 
573 		rel_info_func(&hp_node_info);
574 	}
575 
576 	rel_info_func(&hp_node_info);
577 
578 	return hp_node;
579 }
580 EXPORT_SYMBOL(mdesc_get_node);
581 
582 int mdesc_get_node_info(struct mdesc_handle *hp, u64 node,
583 			const char *node_name, union md_node_info *node_info)
584 {
585 	mdesc_node_info_get_f get_info_func;
586 	int rv;
587 
588 	if (hp == NULL || node == MDESC_NODE_NULL ||
589 	    node_name == NULL || node_info == NULL)
590 		return -EINVAL;
591 
592 	/* Find the get_info op for the given node name */
593 	mdesc_get_node_ops(node_name, &get_info_func, NULL, NULL);
594 
595 	/* If we didn't find a get_info_func, the node name is not supported */
596 	if (get_info_func == NULL) {
597 		pr_err("MD: %s node is not supported\n", node_name);
598 		return -EINVAL;
599 	}
600 
601 	rv = get_info_func(hp, node, node_info);
602 	if (rv != 0) {
603 		pr_err("MD: Cannot find 1 or more required match properties for %s node.\n",
604 		       node_name);
605 		return -1;
606 	}
607 
608 	return 0;
609 }
610 EXPORT_SYMBOL(mdesc_get_node_info);
611 
612 static struct mdesc_elem *node_block(struct mdesc_hdr *mdesc)
613 {
614 	return (struct mdesc_elem *) (mdesc + 1);
615 }
616 
617 static void *name_block(struct mdesc_hdr *mdesc)
618 {
619 	return ((void *) node_block(mdesc)) + mdesc->node_sz;
620 }
621 
622 static void *data_block(struct mdesc_hdr *mdesc)
623 {
624 	return ((void *) name_block(mdesc)) + mdesc->name_sz;
625 }
626 
627 u64 mdesc_node_by_name(struct mdesc_handle *hp,
628 		       u64 from_node, const char *name)
629 {
630 	struct mdesc_elem *ep = node_block(&hp->mdesc);
631 	const char *names = name_block(&hp->mdesc);
632 	u64 last_node = hp->mdesc.node_sz / 16;
633 	u64 ret;
634 
635 	if (from_node == MDESC_NODE_NULL) {
636 		ret = from_node = 0;
637 	} else if (from_node >= last_node) {
638 		return MDESC_NODE_NULL;
639 	} else {
640 		ret = ep[from_node].d.val;
641 	}
642 
643 	while (ret < last_node) {
644 		if (ep[ret].tag != MD_NODE)
645 			return MDESC_NODE_NULL;
646 		if (!strcmp(names + ep[ret].name_offset, name))
647 			break;
648 		ret = ep[ret].d.val;
649 	}
650 	if (ret >= last_node)
651 		ret = MDESC_NODE_NULL;
652 	return ret;
653 }
654 EXPORT_SYMBOL(mdesc_node_by_name);
655 
656 const void *mdesc_get_property(struct mdesc_handle *hp, u64 node,
657 			       const char *name, int *lenp)
658 {
659 	const char *names = name_block(&hp->mdesc);
660 	u64 last_node = hp->mdesc.node_sz / 16;
661 	void *data = data_block(&hp->mdesc);
662 	struct mdesc_elem *ep;
663 
664 	if (node == MDESC_NODE_NULL || node >= last_node)
665 		return NULL;
666 
667 	ep = node_block(&hp->mdesc) + node;
668 	ep++;
669 	for (; ep->tag != MD_NODE_END; ep++) {
670 		void *val = NULL;
671 		int len = 0;
672 
673 		switch (ep->tag) {
674 		case MD_PROP_VAL:
675 			val = &ep->d.val;
676 			len = 8;
677 			break;
678 
679 		case MD_PROP_STR:
680 		case MD_PROP_DATA:
681 			val = data + ep->d.data.data_offset;
682 			len = ep->d.data.data_len;
683 			break;
684 
685 		default:
686 			break;
687 		}
688 		if (!val)
689 			continue;
690 
691 		if (!strcmp(names + ep->name_offset, name)) {
692 			if (lenp)
693 				*lenp = len;
694 			return val;
695 		}
696 	}
697 
698 	return NULL;
699 }
700 EXPORT_SYMBOL(mdesc_get_property);
701 
702 u64 mdesc_next_arc(struct mdesc_handle *hp, u64 from, const char *arc_type)
703 {
704 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
705 	const char *names = name_block(&hp->mdesc);
706 	u64 last_node = hp->mdesc.node_sz / 16;
707 
708 	if (from == MDESC_NODE_NULL || from >= last_node)
709 		return MDESC_NODE_NULL;
710 
711 	ep = base + from;
712 
713 	ep++;
714 	for (; ep->tag != MD_NODE_END; ep++) {
715 		if (ep->tag != MD_PROP_ARC)
716 			continue;
717 
718 		if (strcmp(names + ep->name_offset, arc_type))
719 			continue;
720 
721 		return ep - base;
722 	}
723 
724 	return MDESC_NODE_NULL;
725 }
726 EXPORT_SYMBOL(mdesc_next_arc);
727 
728 u64 mdesc_arc_target(struct mdesc_handle *hp, u64 arc)
729 {
730 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
731 
732 	ep = base + arc;
733 
734 	return ep->d.val;
735 }
736 EXPORT_SYMBOL(mdesc_arc_target);
737 
738 const char *mdesc_node_name(struct mdesc_handle *hp, u64 node)
739 {
740 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
741 	const char *names = name_block(&hp->mdesc);
742 	u64 last_node = hp->mdesc.node_sz / 16;
743 
744 	if (node == MDESC_NODE_NULL || node >= last_node)
745 		return NULL;
746 
747 	ep = base + node;
748 	if (ep->tag != MD_NODE)
749 		return NULL;
750 
751 	return names + ep->name_offset;
752 }
753 EXPORT_SYMBOL(mdesc_node_name);
754 
755 static u64 max_cpus = 64;
756 
757 static void __init report_platform_properties(void)
758 {
759 	struct mdesc_handle *hp = mdesc_grab();
760 	u64 pn = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
761 	const char *s;
762 	const u64 *v;
763 
764 	if (pn == MDESC_NODE_NULL) {
765 		prom_printf("No platform node in machine-description.\n");
766 		prom_halt();
767 	}
768 
769 	s = mdesc_get_property(hp, pn, "banner-name", NULL);
770 	printk("PLATFORM: banner-name [%s]\n", s);
771 	s = mdesc_get_property(hp, pn, "name", NULL);
772 	printk("PLATFORM: name [%s]\n", s);
773 
774 	v = mdesc_get_property(hp, pn, "hostid", NULL);
775 	if (v)
776 		printk("PLATFORM: hostid [%08llx]\n", *v);
777 	v = mdesc_get_property(hp, pn, "serial#", NULL);
778 	if (v)
779 		printk("PLATFORM: serial# [%08llx]\n", *v);
780 	v = mdesc_get_property(hp, pn, "stick-frequency", NULL);
781 	printk("PLATFORM: stick-frequency [%08llx]\n", *v);
782 	v = mdesc_get_property(hp, pn, "mac-address", NULL);
783 	if (v)
784 		printk("PLATFORM: mac-address [%llx]\n", *v);
785 	v = mdesc_get_property(hp, pn, "watchdog-resolution", NULL);
786 	if (v)
787 		printk("PLATFORM: watchdog-resolution [%llu ms]\n", *v);
788 	v = mdesc_get_property(hp, pn, "watchdog-max-timeout", NULL);
789 	if (v)
790 		printk("PLATFORM: watchdog-max-timeout [%llu ms]\n", *v);
791 	v = mdesc_get_property(hp, pn, "max-cpus", NULL);
792 	if (v) {
793 		max_cpus = *v;
794 		printk("PLATFORM: max-cpus [%llu]\n", max_cpus);
795 	}
796 
797 #ifdef CONFIG_SMP
798 	{
799 		int max_cpu, i;
800 
801 		if (v) {
802 			max_cpu = *v;
803 			if (max_cpu > NR_CPUS)
804 				max_cpu = NR_CPUS;
805 		} else {
806 			max_cpu = NR_CPUS;
807 		}
808 		for (i = 0; i < max_cpu; i++)
809 			set_cpu_possible(i, true);
810 	}
811 #endif
812 
813 	mdesc_release(hp);
814 }
815 
816 static void fill_in_one_cache(cpuinfo_sparc *c, struct mdesc_handle *hp, u64 mp)
817 {
818 	const u64 *level = mdesc_get_property(hp, mp, "level", NULL);
819 	const u64 *size = mdesc_get_property(hp, mp, "size", NULL);
820 	const u64 *line_size = mdesc_get_property(hp, mp, "line-size", NULL);
821 	const char *type;
822 	int type_len;
823 
824 	type = mdesc_get_property(hp, mp, "type", &type_len);
825 
826 	switch (*level) {
827 	case 1:
828 		if (of_find_in_proplist(type, "instn", type_len)) {
829 			c->icache_size = *size;
830 			c->icache_line_size = *line_size;
831 		} else if (of_find_in_proplist(type, "data", type_len)) {
832 			c->dcache_size = *size;
833 			c->dcache_line_size = *line_size;
834 		}
835 		break;
836 
837 	case 2:
838 		c->ecache_size = *size;
839 		c->ecache_line_size = *line_size;
840 		break;
841 
842 	default:
843 		break;
844 	}
845 
846 	if (*level == 1) {
847 		u64 a;
848 
849 		mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
850 			u64 target = mdesc_arc_target(hp, a);
851 			const char *name = mdesc_node_name(hp, target);
852 
853 			if (!strcmp(name, "cache"))
854 				fill_in_one_cache(c, hp, target);
855 		}
856 	}
857 }
858 
859 static void find_back_node_value(struct mdesc_handle *hp, u64 node,
860 				 char *srch_val,
861 				 void (*func)(struct mdesc_handle *, u64, int),
862 				 u64 val, int depth)
863 {
864 	u64 arc;
865 
866 	/* Since we have an estimate of recursion depth, do a sanity check. */
867 	if (depth == 0)
868 		return;
869 
870 	mdesc_for_each_arc(arc, hp, node, MDESC_ARC_TYPE_BACK) {
871 		u64 n = mdesc_arc_target(hp, arc);
872 		const char *name = mdesc_node_name(hp, n);
873 
874 		if (!strcmp(srch_val, name))
875 			(*func)(hp, n, val);
876 
877 		find_back_node_value(hp, n, srch_val, func, val, depth-1);
878 	}
879 }
880 
881 static void __mark_core_id(struct mdesc_handle *hp, u64 node,
882 			   int core_id)
883 {
884 	const u64 *id = mdesc_get_property(hp, node, "id", NULL);
885 
886 	if (*id < num_possible_cpus())
887 		cpu_data(*id).core_id = core_id;
888 }
889 
890 static void __mark_max_cache_id(struct mdesc_handle *hp, u64 node,
891 				int max_cache_id)
892 {
893 	const u64 *id = mdesc_get_property(hp, node, "id", NULL);
894 
895 	if (*id < num_possible_cpus()) {
896 		cpu_data(*id).max_cache_id = max_cache_id;
897 
898 		/**
899 		 * On systems without explicit socket descriptions socket
900 		 * is max_cache_id
901 		 */
902 		cpu_data(*id).sock_id = max_cache_id;
903 	}
904 }
905 
906 static void mark_core_ids(struct mdesc_handle *hp, u64 mp,
907 			  int core_id)
908 {
909 	find_back_node_value(hp, mp, "cpu", __mark_core_id, core_id, 10);
910 }
911 
912 static void mark_max_cache_ids(struct mdesc_handle *hp, u64 mp,
913 			       int max_cache_id)
914 {
915 	find_back_node_value(hp, mp, "cpu", __mark_max_cache_id,
916 			     max_cache_id, 10);
917 }
918 
919 static void set_core_ids(struct mdesc_handle *hp)
920 {
921 	int idx;
922 	u64 mp;
923 
924 	idx = 1;
925 
926 	/* Identify unique cores by looking for cpus backpointed to by
927 	 * level 1 instruction caches.
928 	 */
929 	mdesc_for_each_node_by_name(hp, mp, "cache") {
930 		const u64 *level;
931 		const char *type;
932 		int len;
933 
934 		level = mdesc_get_property(hp, mp, "level", NULL);
935 		if (*level != 1)
936 			continue;
937 
938 		type = mdesc_get_property(hp, mp, "type", &len);
939 		if (!of_find_in_proplist(type, "instn", len))
940 			continue;
941 
942 		mark_core_ids(hp, mp, idx);
943 		idx++;
944 	}
945 }
946 
947 static int set_max_cache_ids_by_cache(struct mdesc_handle *hp, int level)
948 {
949 	u64 mp;
950 	int idx = 1;
951 	int fnd = 0;
952 
953 	/**
954 	 * Identify unique highest level of shared cache by looking for cpus
955 	 * backpointed to by shared level N caches.
956 	 */
957 	mdesc_for_each_node_by_name(hp, mp, "cache") {
958 		const u64 *cur_lvl;
959 
960 		cur_lvl = mdesc_get_property(hp, mp, "level", NULL);
961 		if (*cur_lvl != level)
962 			continue;
963 		mark_max_cache_ids(hp, mp, idx);
964 		idx++;
965 		fnd = 1;
966 	}
967 	return fnd;
968 }
969 
970 static void set_sock_ids_by_socket(struct mdesc_handle *hp, u64 mp)
971 {
972 	int idx = 1;
973 
974 	mdesc_for_each_node_by_name(hp, mp, "socket") {
975 		u64 a;
976 
977 		mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
978 			u64 t = mdesc_arc_target(hp, a);
979 			const char *name;
980 			const u64 *id;
981 
982 			name = mdesc_node_name(hp, t);
983 			if (strcmp(name, "cpu"))
984 				continue;
985 
986 			id = mdesc_get_property(hp, t, "id", NULL);
987 			if (*id < num_possible_cpus())
988 				cpu_data(*id).sock_id = idx;
989 		}
990 		idx++;
991 	}
992 }
993 
994 static void set_sock_ids(struct mdesc_handle *hp)
995 {
996 	u64 mp;
997 
998 	/**
999 	 * Find the highest level of shared cache which pre-T7 is also
1000 	 * the socket.
1001 	 */
1002 	if (!set_max_cache_ids_by_cache(hp, 3))
1003 		set_max_cache_ids_by_cache(hp, 2);
1004 
1005 	/* If machine description exposes sockets data use it.*/
1006 	mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "sockets");
1007 	if (mp != MDESC_NODE_NULL)
1008 		set_sock_ids_by_socket(hp, mp);
1009 }
1010 
1011 static void mark_proc_ids(struct mdesc_handle *hp, u64 mp, int proc_id)
1012 {
1013 	u64 a;
1014 
1015 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
1016 		u64 t = mdesc_arc_target(hp, a);
1017 		const char *name;
1018 		const u64 *id;
1019 
1020 		name = mdesc_node_name(hp, t);
1021 		if (strcmp(name, "cpu"))
1022 			continue;
1023 
1024 		id = mdesc_get_property(hp, t, "id", NULL);
1025 		if (*id < NR_CPUS)
1026 			cpu_data(*id).proc_id = proc_id;
1027 	}
1028 }
1029 
1030 static void __set_proc_ids(struct mdesc_handle *hp, const char *exec_unit_name)
1031 {
1032 	int idx;
1033 	u64 mp;
1034 
1035 	idx = 0;
1036 	mdesc_for_each_node_by_name(hp, mp, exec_unit_name) {
1037 		const char *type;
1038 		int len;
1039 
1040 		type = mdesc_get_property(hp, mp, "type", &len);
1041 		if (!of_find_in_proplist(type, "int", len) &&
1042 		    !of_find_in_proplist(type, "integer", len))
1043 			continue;
1044 
1045 		mark_proc_ids(hp, mp, idx);
1046 		idx++;
1047 	}
1048 }
1049 
1050 static void set_proc_ids(struct mdesc_handle *hp)
1051 {
1052 	__set_proc_ids(hp, "exec_unit");
1053 	__set_proc_ids(hp, "exec-unit");
1054 }
1055 
1056 static void get_one_mondo_bits(const u64 *p, unsigned int *mask,
1057 			       unsigned long def, unsigned long max)
1058 {
1059 	u64 val;
1060 
1061 	if (!p)
1062 		goto use_default;
1063 	val = *p;
1064 
1065 	if (!val || val >= 64)
1066 		goto use_default;
1067 
1068 	if (val > max)
1069 		val = max;
1070 
1071 	*mask = ((1U << val) * 64U) - 1U;
1072 	return;
1073 
1074 use_default:
1075 	*mask = ((1U << def) * 64U) - 1U;
1076 }
1077 
1078 static void get_mondo_data(struct mdesc_handle *hp, u64 mp,
1079 			   struct trap_per_cpu *tb)
1080 {
1081 	static int printed;
1082 	const u64 *val;
1083 
1084 	val = mdesc_get_property(hp, mp, "q-cpu-mondo-#bits", NULL);
1085 	get_one_mondo_bits(val, &tb->cpu_mondo_qmask, 7, ilog2(max_cpus * 2));
1086 
1087 	val = mdesc_get_property(hp, mp, "q-dev-mondo-#bits", NULL);
1088 	get_one_mondo_bits(val, &tb->dev_mondo_qmask, 7, 8);
1089 
1090 	val = mdesc_get_property(hp, mp, "q-resumable-#bits", NULL);
1091 	get_one_mondo_bits(val, &tb->resum_qmask, 6, 7);
1092 
1093 	val = mdesc_get_property(hp, mp, "q-nonresumable-#bits", NULL);
1094 	get_one_mondo_bits(val, &tb->nonresum_qmask, 2, 2);
1095 	if (!printed++) {
1096 		pr_info("SUN4V: Mondo queue sizes "
1097 			"[cpu(%u) dev(%u) r(%u) nr(%u)]\n",
1098 			tb->cpu_mondo_qmask + 1,
1099 			tb->dev_mondo_qmask + 1,
1100 			tb->resum_qmask + 1,
1101 			tb->nonresum_qmask + 1);
1102 	}
1103 }
1104 
1105 static void *mdesc_iterate_over_cpus(void *(*func)(struct mdesc_handle *, u64, int, void *), void *arg, cpumask_t *mask)
1106 {
1107 	struct mdesc_handle *hp = mdesc_grab();
1108 	void *ret = NULL;
1109 	u64 mp;
1110 
1111 	mdesc_for_each_node_by_name(hp, mp, "cpu") {
1112 		const u64 *id = mdesc_get_property(hp, mp, "id", NULL);
1113 		int cpuid = *id;
1114 
1115 #ifdef CONFIG_SMP
1116 		if (cpuid >= NR_CPUS) {
1117 			printk(KERN_WARNING "Ignoring CPU %d which is "
1118 			       ">= NR_CPUS (%d)\n",
1119 			       cpuid, NR_CPUS);
1120 			continue;
1121 		}
1122 		if (!cpumask_test_cpu(cpuid, mask))
1123 			continue;
1124 #endif
1125 
1126 		ret = func(hp, mp, cpuid, arg);
1127 		if (ret)
1128 			goto out;
1129 	}
1130 out:
1131 	mdesc_release(hp);
1132 	return ret;
1133 }
1134 
1135 static void *record_one_cpu(struct mdesc_handle *hp, u64 mp, int cpuid,
1136 			    void *arg)
1137 {
1138 	ncpus_probed++;
1139 #ifdef CONFIG_SMP
1140 	set_cpu_present(cpuid, true);
1141 #endif
1142 	return NULL;
1143 }
1144 
1145 void mdesc_populate_present_mask(cpumask_t *mask)
1146 {
1147 	if (tlb_type != hypervisor)
1148 		return;
1149 
1150 	ncpus_probed = 0;
1151 	mdesc_iterate_over_cpus(record_one_cpu, NULL, mask);
1152 }
1153 
1154 static void * __init check_one_pgsz(struct mdesc_handle *hp, u64 mp, int cpuid, void *arg)
1155 {
1156 	const u64 *pgsz_prop = mdesc_get_property(hp, mp, "mmu-page-size-list", NULL);
1157 	unsigned long *pgsz_mask = arg;
1158 	u64 val;
1159 
1160 	val = (HV_PGSZ_MASK_8K | HV_PGSZ_MASK_64K |
1161 	       HV_PGSZ_MASK_512K | HV_PGSZ_MASK_4MB);
1162 	if (pgsz_prop)
1163 		val = *pgsz_prop;
1164 
1165 	if (!*pgsz_mask)
1166 		*pgsz_mask = val;
1167 	else
1168 		*pgsz_mask &= val;
1169 	return NULL;
1170 }
1171 
1172 void __init mdesc_get_page_sizes(cpumask_t *mask, unsigned long *pgsz_mask)
1173 {
1174 	*pgsz_mask = 0;
1175 	mdesc_iterate_over_cpus(check_one_pgsz, pgsz_mask, mask);
1176 }
1177 
1178 static void *fill_in_one_cpu(struct mdesc_handle *hp, u64 mp, int cpuid,
1179 			     void *arg)
1180 {
1181 	const u64 *cfreq = mdesc_get_property(hp, mp, "clock-frequency", NULL);
1182 	struct trap_per_cpu *tb;
1183 	cpuinfo_sparc *c;
1184 	u64 a;
1185 
1186 #ifndef CONFIG_SMP
1187 	/* On uniprocessor we only want the values for the
1188 	 * real physical cpu the kernel booted onto, however
1189 	 * cpu_data() only has one entry at index 0.
1190 	 */
1191 	if (cpuid != real_hard_smp_processor_id())
1192 		return NULL;
1193 	cpuid = 0;
1194 #endif
1195 
1196 	c = &cpu_data(cpuid);
1197 	c->clock_tick = *cfreq;
1198 
1199 	tb = &trap_block[cpuid];
1200 	get_mondo_data(hp, mp, tb);
1201 
1202 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
1203 		u64 j, t = mdesc_arc_target(hp, a);
1204 		const char *t_name;
1205 
1206 		t_name = mdesc_node_name(hp, t);
1207 		if (!strcmp(t_name, "cache")) {
1208 			fill_in_one_cache(c, hp, t);
1209 			continue;
1210 		}
1211 
1212 		mdesc_for_each_arc(j, hp, t, MDESC_ARC_TYPE_FWD) {
1213 			u64 n = mdesc_arc_target(hp, j);
1214 			const char *n_name;
1215 
1216 			n_name = mdesc_node_name(hp, n);
1217 			if (!strcmp(n_name, "cache"))
1218 				fill_in_one_cache(c, hp, n);
1219 		}
1220 	}
1221 
1222 	c->core_id = 0;
1223 	c->proc_id = -1;
1224 
1225 	return NULL;
1226 }
1227 
1228 void mdesc_fill_in_cpu_data(cpumask_t *mask)
1229 {
1230 	struct mdesc_handle *hp;
1231 
1232 	mdesc_iterate_over_cpus(fill_in_one_cpu, NULL, mask);
1233 
1234 	hp = mdesc_grab();
1235 
1236 	set_core_ids(hp);
1237 	set_proc_ids(hp);
1238 	set_sock_ids(hp);
1239 
1240 	mdesc_release(hp);
1241 
1242 	smp_fill_in_sib_core_maps();
1243 }
1244 
1245 /* mdesc_open() - Grab a reference to mdesc_handle when /dev/mdesc is
1246  * opened. Hold this reference until /dev/mdesc is closed to ensure
1247  * mdesc data structure is not released underneath us. Store the
1248  * pointer to mdesc structure in private_data for read and seek to use
1249  */
1250 static int mdesc_open(struct inode *inode, struct file *file)
1251 {
1252 	struct mdesc_handle *hp = mdesc_grab();
1253 
1254 	if (!hp)
1255 		return -ENODEV;
1256 
1257 	file->private_data = hp;
1258 
1259 	return 0;
1260 }
1261 
1262 static ssize_t mdesc_read(struct file *file, char __user *buf,
1263 			  size_t len, loff_t *offp)
1264 {
1265 	struct mdesc_handle *hp = file->private_data;
1266 	unsigned char *mdesc;
1267 	int bytes_left, count = len;
1268 
1269 	if (*offp >= hp->handle_size)
1270 		return 0;
1271 
1272 	bytes_left = hp->handle_size - *offp;
1273 	if (count > bytes_left)
1274 		count = bytes_left;
1275 
1276 	mdesc = (unsigned char *)&hp->mdesc;
1277 	mdesc += *offp;
1278 	if (!copy_to_user(buf, mdesc, count)) {
1279 		*offp += count;
1280 		return count;
1281 	} else {
1282 		return -EFAULT;
1283 	}
1284 }
1285 
1286 static loff_t mdesc_llseek(struct file *file, loff_t offset, int whence)
1287 {
1288 	struct mdesc_handle *hp = file->private_data;
1289 
1290 	return no_seek_end_llseek_size(file, offset, whence, hp->handle_size);
1291 }
1292 
1293 /* mdesc_close() - /dev/mdesc is being closed, release the reference to
1294  * mdesc structure.
1295  */
1296 static int mdesc_close(struct inode *inode, struct file *file)
1297 {
1298 	mdesc_release(file->private_data);
1299 	return 0;
1300 }
1301 
1302 static const struct file_operations mdesc_fops = {
1303 	.open    = mdesc_open,
1304 	.read	 = mdesc_read,
1305 	.llseek  = mdesc_llseek,
1306 	.release = mdesc_close,
1307 	.owner	 = THIS_MODULE,
1308 };
1309 
1310 static struct miscdevice mdesc_misc = {
1311 	.minor	= MISC_DYNAMIC_MINOR,
1312 	.name	= "mdesc",
1313 	.fops	= &mdesc_fops,
1314 };
1315 
1316 static int __init mdesc_misc_init(void)
1317 {
1318 	return misc_register(&mdesc_misc);
1319 }
1320 
1321 __initcall(mdesc_misc_init);
1322 
1323 void __init sun4v_mdesc_init(void)
1324 {
1325 	struct mdesc_handle *hp;
1326 	unsigned long len, real_len, status;
1327 
1328 	(void) sun4v_mach_desc(0UL, 0UL, &len);
1329 
1330 	printk("MDESC: Size is %lu bytes.\n", len);
1331 
1332 	hp = mdesc_alloc(len, &memblock_mdesc_ops);
1333 	if (hp == NULL) {
1334 		prom_printf("MDESC: alloc of %lu bytes failed.\n", len);
1335 		prom_halt();
1336 	}
1337 
1338 	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
1339 	if (status != HV_EOK || real_len > len) {
1340 		prom_printf("sun4v_mach_desc fails, err(%lu), "
1341 			    "len(%lu), real_len(%lu)\n",
1342 			    status, len, real_len);
1343 		mdesc_free(hp);
1344 		prom_halt();
1345 	}
1346 
1347 	cur_mdesc = hp;
1348 
1349 	mdesc_adi_init();
1350 	report_platform_properties();
1351 }
1352