xref: /openbmc/linux/arch/sparc/kernel/mdesc.c (revision b24413180f5600bcb3bb70fbed5cf186b60864bd)
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 
17 #include <asm/cpudata.h>
18 #include <asm/hypervisor.h>
19 #include <asm/mdesc.h>
20 #include <asm/prom.h>
21 #include <linux/uaccess.h>
22 #include <asm/oplib.h>
23 #include <asm/smp.h>
24 
25 /* Unlike the OBP device tree, the machine description is a full-on
26  * DAG.  An arbitrary number of ARCs are possible from one
27  * node to other nodes and thus we can't use the OBP device_node
28  * data structure to represent these nodes inside of the kernel.
29  *
30  * Actually, it isn't even a DAG, because there are back pointers
31  * which create cycles in the graph.
32  *
33  * mdesc_hdr and mdesc_elem describe the layout of the data structure
34  * we get from the Hypervisor.
35  */
36 struct mdesc_hdr {
37 	u32	version; /* Transport version */
38 	u32	node_sz; /* node block size */
39 	u32	name_sz; /* name block size */
40 	u32	data_sz; /* data block size */
41 } __attribute__((aligned(16)));
42 
43 struct mdesc_elem {
44 	u8	tag;
45 #define MD_LIST_END	0x00
46 #define MD_NODE		0x4e
47 #define MD_NODE_END	0x45
48 #define MD_NOOP		0x20
49 #define MD_PROP_ARC	0x61
50 #define MD_PROP_VAL	0x76
51 #define MD_PROP_STR	0x73
52 #define MD_PROP_DATA	0x64
53 	u8	name_len;
54 	u16	resv;
55 	u32	name_offset;
56 	union {
57 		struct {
58 			u32	data_len;
59 			u32	data_offset;
60 		} data;
61 		u64	val;
62 	} d;
63 };
64 
65 struct mdesc_mem_ops {
66 	struct mdesc_handle *(*alloc)(unsigned int mdesc_size);
67 	void (*free)(struct mdesc_handle *handle);
68 };
69 
70 struct mdesc_handle {
71 	struct list_head	list;
72 	struct mdesc_mem_ops	*mops;
73 	void			*self_base;
74 	atomic_t		refcnt;
75 	unsigned int		handle_size;
76 	struct mdesc_hdr	mdesc;
77 };
78 
79 typedef int (*mdesc_node_info_get_f)(struct mdesc_handle *, u64,
80 				     union md_node_info *);
81 typedef void (*mdesc_node_info_rel_f)(union md_node_info *);
82 typedef bool (*mdesc_node_match_f)(union md_node_info *, union md_node_info *);
83 
84 struct md_node_ops {
85 	char			*name;
86 	mdesc_node_info_get_f	get_info;
87 	mdesc_node_info_rel_f	rel_info;
88 	mdesc_node_match_f	node_match;
89 };
90 
91 static int get_vdev_port_node_info(struct mdesc_handle *md, u64 node,
92 				   union md_node_info *node_info);
93 static void rel_vdev_port_node_info(union md_node_info *node_info);
94 static bool vdev_port_node_match(union md_node_info *a_node_info,
95 				 union md_node_info *b_node_info);
96 
97 static int get_ds_port_node_info(struct mdesc_handle *md, u64 node,
98 				 union md_node_info *node_info);
99 static void rel_ds_port_node_info(union md_node_info *node_info);
100 static bool ds_port_node_match(union md_node_info *a_node_info,
101 			       union md_node_info *b_node_info);
102 
103 /* supported node types which can be registered */
104 static struct md_node_ops md_node_ops_table[] = {
105 	{"virtual-device-port", get_vdev_port_node_info,
106 	 rel_vdev_port_node_info, vdev_port_node_match},
107 	{"domain-services-port", get_ds_port_node_info,
108 	 rel_ds_port_node_info, ds_port_node_match},
109 	{NULL, NULL, NULL, NULL}
110 };
111 
112 static void mdesc_get_node_ops(const char *node_name,
113 			       mdesc_node_info_get_f *get_info_f,
114 			       mdesc_node_info_rel_f *rel_info_f,
115 			       mdesc_node_match_f *match_f)
116 {
117 	int i;
118 
119 	if (get_info_f)
120 		*get_info_f = NULL;
121 
122 	if (rel_info_f)
123 		*rel_info_f = NULL;
124 
125 	if (match_f)
126 		*match_f = NULL;
127 
128 	if (!node_name)
129 		return;
130 
131 	for (i = 0; md_node_ops_table[i].name != NULL; i++) {
132 		if (strcmp(md_node_ops_table[i].name, node_name) == 0) {
133 			if (get_info_f)
134 				*get_info_f = md_node_ops_table[i].get_info;
135 
136 			if (rel_info_f)
137 				*rel_info_f = md_node_ops_table[i].rel_info;
138 
139 			if (match_f)
140 				*match_f = md_node_ops_table[i].node_match;
141 
142 			break;
143 		}
144 	}
145 }
146 
147 static void mdesc_handle_init(struct mdesc_handle *hp,
148 			      unsigned int handle_size,
149 			      void *base)
150 {
151 	BUG_ON(((unsigned long)&hp->mdesc) & (16UL - 1));
152 
153 	memset(hp, 0, handle_size);
154 	INIT_LIST_HEAD(&hp->list);
155 	hp->self_base = base;
156 	atomic_set(&hp->refcnt, 1);
157 	hp->handle_size = handle_size;
158 }
159 
160 static struct mdesc_handle * __init mdesc_memblock_alloc(unsigned int mdesc_size)
161 {
162 	unsigned int handle_size, alloc_size;
163 	struct mdesc_handle *hp;
164 	unsigned long paddr;
165 
166 	handle_size = (sizeof(struct mdesc_handle) -
167 		       sizeof(struct mdesc_hdr) +
168 		       mdesc_size);
169 	alloc_size = PAGE_ALIGN(handle_size);
170 
171 	paddr = memblock_alloc(alloc_size, PAGE_SIZE);
172 
173 	hp = NULL;
174 	if (paddr) {
175 		hp = __va(paddr);
176 		mdesc_handle_init(hp, handle_size, hp);
177 	}
178 	return hp;
179 }
180 
181 static void __init mdesc_memblock_free(struct mdesc_handle *hp)
182 {
183 	unsigned int alloc_size;
184 	unsigned long start;
185 
186 	BUG_ON(atomic_read(&hp->refcnt) != 0);
187 	BUG_ON(!list_empty(&hp->list));
188 
189 	alloc_size = PAGE_ALIGN(hp->handle_size);
190 	start = __pa(hp);
191 	free_bootmem_late(start, alloc_size);
192 }
193 
194 static struct mdesc_mem_ops memblock_mdesc_ops = {
195 	.alloc = mdesc_memblock_alloc,
196 	.free  = mdesc_memblock_free,
197 };
198 
199 static struct mdesc_handle *mdesc_kmalloc(unsigned int mdesc_size)
200 {
201 	unsigned int handle_size;
202 	struct mdesc_handle *hp;
203 	unsigned long addr;
204 	void *base;
205 
206 	handle_size = (sizeof(struct mdesc_handle) -
207 		       sizeof(struct mdesc_hdr) +
208 		       mdesc_size);
209 	base = kmalloc(handle_size + 15, GFP_KERNEL | __GFP_RETRY_MAYFAIL);
210 	if (!base)
211 		return NULL;
212 
213 	addr = (unsigned long)base;
214 	addr = (addr + 15UL) & ~15UL;
215 	hp = (struct mdesc_handle *) addr;
216 
217 	mdesc_handle_init(hp, handle_size, base);
218 
219 	return hp;
220 }
221 
222 static void mdesc_kfree(struct mdesc_handle *hp)
223 {
224 	BUG_ON(atomic_read(&hp->refcnt) != 0);
225 	BUG_ON(!list_empty(&hp->list));
226 
227 	kfree(hp->self_base);
228 }
229 
230 static struct mdesc_mem_ops kmalloc_mdesc_memops = {
231 	.alloc = mdesc_kmalloc,
232 	.free  = mdesc_kfree,
233 };
234 
235 static struct mdesc_handle *mdesc_alloc(unsigned int mdesc_size,
236 					struct mdesc_mem_ops *mops)
237 {
238 	struct mdesc_handle *hp = mops->alloc(mdesc_size);
239 
240 	if (hp)
241 		hp->mops = mops;
242 
243 	return hp;
244 }
245 
246 static void mdesc_free(struct mdesc_handle *hp)
247 {
248 	hp->mops->free(hp);
249 }
250 
251 static struct mdesc_handle *cur_mdesc;
252 static LIST_HEAD(mdesc_zombie_list);
253 static DEFINE_SPINLOCK(mdesc_lock);
254 
255 struct mdesc_handle *mdesc_grab(void)
256 {
257 	struct mdesc_handle *hp;
258 	unsigned long flags;
259 
260 	spin_lock_irqsave(&mdesc_lock, flags);
261 	hp = cur_mdesc;
262 	if (hp)
263 		atomic_inc(&hp->refcnt);
264 	spin_unlock_irqrestore(&mdesc_lock, flags);
265 
266 	return hp;
267 }
268 EXPORT_SYMBOL(mdesc_grab);
269 
270 void mdesc_release(struct mdesc_handle *hp)
271 {
272 	unsigned long flags;
273 
274 	spin_lock_irqsave(&mdesc_lock, flags);
275 	if (atomic_dec_and_test(&hp->refcnt)) {
276 		list_del_init(&hp->list);
277 		hp->mops->free(hp);
278 	}
279 	spin_unlock_irqrestore(&mdesc_lock, flags);
280 }
281 EXPORT_SYMBOL(mdesc_release);
282 
283 static DEFINE_MUTEX(mdesc_mutex);
284 static struct mdesc_notifier_client *client_list;
285 
286 void mdesc_register_notifier(struct mdesc_notifier_client *client)
287 {
288 	bool supported = false;
289 	u64 node;
290 	int i;
291 
292 	mutex_lock(&mdesc_mutex);
293 
294 	/* check to see if the node is supported for registration */
295 	for (i = 0; md_node_ops_table[i].name != NULL; i++) {
296 		if (strcmp(md_node_ops_table[i].name, client->node_name) == 0) {
297 			supported = true;
298 			break;
299 		}
300 	}
301 
302 	if (!supported) {
303 		pr_err("MD: %s node not supported\n", client->node_name);
304 		mutex_unlock(&mdesc_mutex);
305 		return;
306 	}
307 
308 	client->next = client_list;
309 	client_list = client;
310 
311 	mdesc_for_each_node_by_name(cur_mdesc, node, client->node_name)
312 		client->add(cur_mdesc, node, client->node_name);
313 
314 	mutex_unlock(&mdesc_mutex);
315 }
316 
317 static const u64 *parent_cfg_handle(struct mdesc_handle *hp, u64 node)
318 {
319 	const u64 *id;
320 	u64 a;
321 
322 	id = NULL;
323 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
324 		u64 target;
325 
326 		target = mdesc_arc_target(hp, a);
327 		id = mdesc_get_property(hp, target,
328 					"cfg-handle", NULL);
329 		if (id)
330 			break;
331 	}
332 
333 	return id;
334 }
335 
336 static int get_vdev_port_node_info(struct mdesc_handle *md, u64 node,
337 				   union md_node_info *node_info)
338 {
339 	const u64 *parent_cfg_hdlp;
340 	const char *name;
341 	const u64 *idp;
342 
343 	/*
344 	 * Virtual device nodes are distinguished by:
345 	 * 1. "id" property
346 	 * 2. "name" property
347 	 * 3. parent node "cfg-handle" property
348 	 */
349 	idp = mdesc_get_property(md, node, "id", NULL);
350 	name = mdesc_get_property(md, node, "name", NULL);
351 	parent_cfg_hdlp = parent_cfg_handle(md, node);
352 
353 	if (!idp || !name || !parent_cfg_hdlp)
354 		return -1;
355 
356 	node_info->vdev_port.id = *idp;
357 	node_info->vdev_port.name = kstrdup_const(name, GFP_KERNEL);
358 	node_info->vdev_port.parent_cfg_hdl = *parent_cfg_hdlp;
359 
360 	return 0;
361 }
362 
363 static void rel_vdev_port_node_info(union md_node_info *node_info)
364 {
365 	if (node_info && node_info->vdev_port.name) {
366 		kfree_const(node_info->vdev_port.name);
367 		node_info->vdev_port.name = NULL;
368 	}
369 }
370 
371 static bool vdev_port_node_match(union md_node_info *a_node_info,
372 				 union md_node_info *b_node_info)
373 {
374 	if (a_node_info->vdev_port.id != b_node_info->vdev_port.id)
375 		return false;
376 
377 	if (a_node_info->vdev_port.parent_cfg_hdl !=
378 	    b_node_info->vdev_port.parent_cfg_hdl)
379 		return false;
380 
381 	if (strncmp(a_node_info->vdev_port.name,
382 		    b_node_info->vdev_port.name, MDESC_MAX_STR_LEN) != 0)
383 		return false;
384 
385 	return true;
386 }
387 
388 static int get_ds_port_node_info(struct mdesc_handle *md, u64 node,
389 				 union md_node_info *node_info)
390 {
391 	const u64 *idp;
392 
393 	/* DS port nodes use the "id" property to distinguish them */
394 	idp = mdesc_get_property(md, node, "id", NULL);
395 	if (!idp)
396 		return -1;
397 
398 	node_info->ds_port.id = *idp;
399 
400 	return 0;
401 }
402 
403 static void rel_ds_port_node_info(union md_node_info *node_info)
404 {
405 }
406 
407 static bool ds_port_node_match(union md_node_info *a_node_info,
408 			       union md_node_info *b_node_info)
409 {
410 	if (a_node_info->ds_port.id != b_node_info->ds_port.id)
411 		return false;
412 
413 	return true;
414 }
415 
416 /* Run 'func' on nodes which are in A but not in B.  */
417 static void invoke_on_missing(const char *name,
418 			      struct mdesc_handle *a,
419 			      struct mdesc_handle *b,
420 			      void (*func)(struct mdesc_handle *, u64,
421 					   const char *node_name))
422 {
423 	mdesc_node_info_get_f get_info_func;
424 	mdesc_node_info_rel_f rel_info_func;
425 	mdesc_node_match_f node_match_func;
426 	union md_node_info a_node_info;
427 	union md_node_info b_node_info;
428 	bool found;
429 	u64 a_node;
430 	u64 b_node;
431 	int rv;
432 
433 	/*
434 	 * Find the get_info, rel_info and node_match ops for the given
435 	 * node name
436 	 */
437 	mdesc_get_node_ops(name, &get_info_func, &rel_info_func,
438 			   &node_match_func);
439 
440 	/* If we didn't find a match, the node type is not supported */
441 	if (!get_info_func || !rel_info_func || !node_match_func) {
442 		pr_err("MD: %s node type is not supported\n", name);
443 		return;
444 	}
445 
446 	mdesc_for_each_node_by_name(a, a_node, name) {
447 		found = false;
448 
449 		rv = get_info_func(a, a_node, &a_node_info);
450 		if (rv != 0) {
451 			pr_err("MD: Cannot find 1 or more required match properties for %s node.\n",
452 			       name);
453 			continue;
454 		}
455 
456 		/* Check each node in B for node matching a_node */
457 		mdesc_for_each_node_by_name(b, b_node, name) {
458 			rv = get_info_func(b, b_node, &b_node_info);
459 			if (rv != 0)
460 				continue;
461 
462 			if (node_match_func(&a_node_info, &b_node_info)) {
463 				found = true;
464 				rel_info_func(&b_node_info);
465 				break;
466 			}
467 
468 			rel_info_func(&b_node_info);
469 		}
470 
471 		rel_info_func(&a_node_info);
472 
473 		if (!found)
474 			func(a, a_node, name);
475 	}
476 }
477 
478 static void notify_one(struct mdesc_notifier_client *p,
479 		       struct mdesc_handle *old_hp,
480 		       struct mdesc_handle *new_hp)
481 {
482 	invoke_on_missing(p->node_name, old_hp, new_hp, p->remove);
483 	invoke_on_missing(p->node_name, new_hp, old_hp, p->add);
484 }
485 
486 static void mdesc_notify_clients(struct mdesc_handle *old_hp,
487 				 struct mdesc_handle *new_hp)
488 {
489 	struct mdesc_notifier_client *p = client_list;
490 
491 	while (p) {
492 		notify_one(p, old_hp, new_hp);
493 		p = p->next;
494 	}
495 }
496 
497 void mdesc_update(void)
498 {
499 	unsigned long len, real_len, status;
500 	struct mdesc_handle *hp, *orig_hp;
501 	unsigned long flags;
502 
503 	mutex_lock(&mdesc_mutex);
504 
505 	(void) sun4v_mach_desc(0UL, 0UL, &len);
506 
507 	hp = mdesc_alloc(len, &kmalloc_mdesc_memops);
508 	if (!hp) {
509 		printk(KERN_ERR "MD: mdesc alloc fails\n");
510 		goto out;
511 	}
512 
513 	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
514 	if (status != HV_EOK || real_len > len) {
515 		printk(KERN_ERR "MD: mdesc reread fails with %lu\n",
516 		       status);
517 		atomic_dec(&hp->refcnt);
518 		mdesc_free(hp);
519 		goto out;
520 	}
521 
522 	spin_lock_irqsave(&mdesc_lock, flags);
523 	orig_hp = cur_mdesc;
524 	cur_mdesc = hp;
525 	spin_unlock_irqrestore(&mdesc_lock, flags);
526 
527 	mdesc_notify_clients(orig_hp, hp);
528 
529 	spin_lock_irqsave(&mdesc_lock, flags);
530 	if (atomic_dec_and_test(&orig_hp->refcnt))
531 		mdesc_free(orig_hp);
532 	else
533 		list_add(&orig_hp->list, &mdesc_zombie_list);
534 	spin_unlock_irqrestore(&mdesc_lock, flags);
535 
536 out:
537 	mutex_unlock(&mdesc_mutex);
538 }
539 
540 u64 mdesc_get_node(struct mdesc_handle *hp, const char *node_name,
541 		   union md_node_info *node_info)
542 {
543 	mdesc_node_info_get_f get_info_func;
544 	mdesc_node_info_rel_f rel_info_func;
545 	mdesc_node_match_f node_match_func;
546 	union md_node_info hp_node_info;
547 	u64 hp_node;
548 	int rv;
549 
550 	if (hp == NULL || node_name == NULL || node_info == NULL)
551 		return MDESC_NODE_NULL;
552 
553 	/* Find the ops for the given node name */
554 	mdesc_get_node_ops(node_name, &get_info_func, &rel_info_func,
555 			   &node_match_func);
556 
557 	/* If we didn't find ops for the given node name, it is not supported */
558 	if (!get_info_func || !rel_info_func || !node_match_func) {
559 		pr_err("MD: %s node is not supported\n", node_name);
560 		return -EINVAL;
561 	}
562 
563 	mdesc_for_each_node_by_name(hp, hp_node, node_name) {
564 		rv = get_info_func(hp, hp_node, &hp_node_info);
565 		if (rv != 0)
566 			continue;
567 
568 		if (node_match_func(node_info, &hp_node_info))
569 			break;
570 
571 		rel_info_func(&hp_node_info);
572 	}
573 
574 	rel_info_func(&hp_node_info);
575 
576 	return hp_node;
577 }
578 EXPORT_SYMBOL(mdesc_get_node);
579 
580 int mdesc_get_node_info(struct mdesc_handle *hp, u64 node,
581 			const char *node_name, union md_node_info *node_info)
582 {
583 	mdesc_node_info_get_f get_info_func;
584 	int rv;
585 
586 	if (hp == NULL || node == MDESC_NODE_NULL ||
587 	    node_name == NULL || node_info == NULL)
588 		return -EINVAL;
589 
590 	/* Find the get_info op for the given node name */
591 	mdesc_get_node_ops(node_name, &get_info_func, NULL, NULL);
592 
593 	/* If we didn't find a get_info_func, the node name is not supported */
594 	if (get_info_func == NULL) {
595 		pr_err("MD: %s node is not supported\n", node_name);
596 		return -EINVAL;
597 	}
598 
599 	rv = get_info_func(hp, node, node_info);
600 	if (rv != 0) {
601 		pr_err("MD: Cannot find 1 or more required match properties for %s node.\n",
602 		       node_name);
603 		return -1;
604 	}
605 
606 	return 0;
607 }
608 EXPORT_SYMBOL(mdesc_get_node_info);
609 
610 static struct mdesc_elem *node_block(struct mdesc_hdr *mdesc)
611 {
612 	return (struct mdesc_elem *) (mdesc + 1);
613 }
614 
615 static void *name_block(struct mdesc_hdr *mdesc)
616 {
617 	return ((void *) node_block(mdesc)) + mdesc->node_sz;
618 }
619 
620 static void *data_block(struct mdesc_hdr *mdesc)
621 {
622 	return ((void *) name_block(mdesc)) + mdesc->name_sz;
623 }
624 
625 u64 mdesc_node_by_name(struct mdesc_handle *hp,
626 		       u64 from_node, const char *name)
627 {
628 	struct mdesc_elem *ep = node_block(&hp->mdesc);
629 	const char *names = name_block(&hp->mdesc);
630 	u64 last_node = hp->mdesc.node_sz / 16;
631 	u64 ret;
632 
633 	if (from_node == MDESC_NODE_NULL) {
634 		ret = from_node = 0;
635 	} else if (from_node >= last_node) {
636 		return MDESC_NODE_NULL;
637 	} else {
638 		ret = ep[from_node].d.val;
639 	}
640 
641 	while (ret < last_node) {
642 		if (ep[ret].tag != MD_NODE)
643 			return MDESC_NODE_NULL;
644 		if (!strcmp(names + ep[ret].name_offset, name))
645 			break;
646 		ret = ep[ret].d.val;
647 	}
648 	if (ret >= last_node)
649 		ret = MDESC_NODE_NULL;
650 	return ret;
651 }
652 EXPORT_SYMBOL(mdesc_node_by_name);
653 
654 const void *mdesc_get_property(struct mdesc_handle *hp, u64 node,
655 			       const char *name, int *lenp)
656 {
657 	const char *names = name_block(&hp->mdesc);
658 	u64 last_node = hp->mdesc.node_sz / 16;
659 	void *data = data_block(&hp->mdesc);
660 	struct mdesc_elem *ep;
661 
662 	if (node == MDESC_NODE_NULL || node >= last_node)
663 		return NULL;
664 
665 	ep = node_block(&hp->mdesc) + node;
666 	ep++;
667 	for (; ep->tag != MD_NODE_END; ep++) {
668 		void *val = NULL;
669 		int len = 0;
670 
671 		switch (ep->tag) {
672 		case MD_PROP_VAL:
673 			val = &ep->d.val;
674 			len = 8;
675 			break;
676 
677 		case MD_PROP_STR:
678 		case MD_PROP_DATA:
679 			val = data + ep->d.data.data_offset;
680 			len = ep->d.data.data_len;
681 			break;
682 
683 		default:
684 			break;
685 		}
686 		if (!val)
687 			continue;
688 
689 		if (!strcmp(names + ep->name_offset, name)) {
690 			if (lenp)
691 				*lenp = len;
692 			return val;
693 		}
694 	}
695 
696 	return NULL;
697 }
698 EXPORT_SYMBOL(mdesc_get_property);
699 
700 u64 mdesc_next_arc(struct mdesc_handle *hp, u64 from, const char *arc_type)
701 {
702 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
703 	const char *names = name_block(&hp->mdesc);
704 	u64 last_node = hp->mdesc.node_sz / 16;
705 
706 	if (from == MDESC_NODE_NULL || from >= last_node)
707 		return MDESC_NODE_NULL;
708 
709 	ep = base + from;
710 
711 	ep++;
712 	for (; ep->tag != MD_NODE_END; ep++) {
713 		if (ep->tag != MD_PROP_ARC)
714 			continue;
715 
716 		if (strcmp(names + ep->name_offset, arc_type))
717 			continue;
718 
719 		return ep - base;
720 	}
721 
722 	return MDESC_NODE_NULL;
723 }
724 EXPORT_SYMBOL(mdesc_next_arc);
725 
726 u64 mdesc_arc_target(struct mdesc_handle *hp, u64 arc)
727 {
728 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
729 
730 	ep = base + arc;
731 
732 	return ep->d.val;
733 }
734 EXPORT_SYMBOL(mdesc_arc_target);
735 
736 const char *mdesc_node_name(struct mdesc_handle *hp, u64 node)
737 {
738 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
739 	const char *names = name_block(&hp->mdesc);
740 	u64 last_node = hp->mdesc.node_sz / 16;
741 
742 	if (node == MDESC_NODE_NULL || node >= last_node)
743 		return NULL;
744 
745 	ep = base + node;
746 	if (ep->tag != MD_NODE)
747 		return NULL;
748 
749 	return names + ep->name_offset;
750 }
751 EXPORT_SYMBOL(mdesc_node_name);
752 
753 static u64 max_cpus = 64;
754 
755 static void __init report_platform_properties(void)
756 {
757 	struct mdesc_handle *hp = mdesc_grab();
758 	u64 pn = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
759 	const char *s;
760 	const u64 *v;
761 
762 	if (pn == MDESC_NODE_NULL) {
763 		prom_printf("No platform node in machine-description.\n");
764 		prom_halt();
765 	}
766 
767 	s = mdesc_get_property(hp, pn, "banner-name", NULL);
768 	printk("PLATFORM: banner-name [%s]\n", s);
769 	s = mdesc_get_property(hp, pn, "name", NULL);
770 	printk("PLATFORM: name [%s]\n", s);
771 
772 	v = mdesc_get_property(hp, pn, "hostid", NULL);
773 	if (v)
774 		printk("PLATFORM: hostid [%08llx]\n", *v);
775 	v = mdesc_get_property(hp, pn, "serial#", NULL);
776 	if (v)
777 		printk("PLATFORM: serial# [%08llx]\n", *v);
778 	v = mdesc_get_property(hp, pn, "stick-frequency", NULL);
779 	printk("PLATFORM: stick-frequency [%08llx]\n", *v);
780 	v = mdesc_get_property(hp, pn, "mac-address", NULL);
781 	if (v)
782 		printk("PLATFORM: mac-address [%llx]\n", *v);
783 	v = mdesc_get_property(hp, pn, "watchdog-resolution", NULL);
784 	if (v)
785 		printk("PLATFORM: watchdog-resolution [%llu ms]\n", *v);
786 	v = mdesc_get_property(hp, pn, "watchdog-max-timeout", NULL);
787 	if (v)
788 		printk("PLATFORM: watchdog-max-timeout [%llu ms]\n", *v);
789 	v = mdesc_get_property(hp, pn, "max-cpus", NULL);
790 	if (v) {
791 		max_cpus = *v;
792 		printk("PLATFORM: max-cpus [%llu]\n", max_cpus);
793 	}
794 
795 #ifdef CONFIG_SMP
796 	{
797 		int max_cpu, i;
798 
799 		if (v) {
800 			max_cpu = *v;
801 			if (max_cpu > NR_CPUS)
802 				max_cpu = NR_CPUS;
803 		} else {
804 			max_cpu = NR_CPUS;
805 		}
806 		for (i = 0; i < max_cpu; i++)
807 			set_cpu_possible(i, true);
808 	}
809 #endif
810 
811 	mdesc_release(hp);
812 }
813 
814 static void fill_in_one_cache(cpuinfo_sparc *c, struct mdesc_handle *hp, u64 mp)
815 {
816 	const u64 *level = mdesc_get_property(hp, mp, "level", NULL);
817 	const u64 *size = mdesc_get_property(hp, mp, "size", NULL);
818 	const u64 *line_size = mdesc_get_property(hp, mp, "line-size", NULL);
819 	const char *type;
820 	int type_len;
821 
822 	type = mdesc_get_property(hp, mp, "type", &type_len);
823 
824 	switch (*level) {
825 	case 1:
826 		if (of_find_in_proplist(type, "instn", type_len)) {
827 			c->icache_size = *size;
828 			c->icache_line_size = *line_size;
829 		} else if (of_find_in_proplist(type, "data", type_len)) {
830 			c->dcache_size = *size;
831 			c->dcache_line_size = *line_size;
832 		}
833 		break;
834 
835 	case 2:
836 		c->ecache_size = *size;
837 		c->ecache_line_size = *line_size;
838 		break;
839 
840 	default:
841 		break;
842 	}
843 
844 	if (*level == 1) {
845 		u64 a;
846 
847 		mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
848 			u64 target = mdesc_arc_target(hp, a);
849 			const char *name = mdesc_node_name(hp, target);
850 
851 			if (!strcmp(name, "cache"))
852 				fill_in_one_cache(c, hp, target);
853 		}
854 	}
855 }
856 
857 static void find_back_node_value(struct mdesc_handle *hp, u64 node,
858 				 char *srch_val,
859 				 void (*func)(struct mdesc_handle *, u64, int),
860 				 u64 val, int depth)
861 {
862 	u64 arc;
863 
864 	/* Since we have an estimate of recursion depth, do a sanity check. */
865 	if (depth == 0)
866 		return;
867 
868 	mdesc_for_each_arc(arc, hp, node, MDESC_ARC_TYPE_BACK) {
869 		u64 n = mdesc_arc_target(hp, arc);
870 		const char *name = mdesc_node_name(hp, n);
871 
872 		if (!strcmp(srch_val, name))
873 			(*func)(hp, n, val);
874 
875 		find_back_node_value(hp, n, srch_val, func, val, depth-1);
876 	}
877 }
878 
879 static void __mark_core_id(struct mdesc_handle *hp, u64 node,
880 			   int core_id)
881 {
882 	const u64 *id = mdesc_get_property(hp, node, "id", NULL);
883 
884 	if (*id < num_possible_cpus())
885 		cpu_data(*id).core_id = core_id;
886 }
887 
888 static void __mark_max_cache_id(struct mdesc_handle *hp, u64 node,
889 				int max_cache_id)
890 {
891 	const u64 *id = mdesc_get_property(hp, node, "id", NULL);
892 
893 	if (*id < num_possible_cpus()) {
894 		cpu_data(*id).max_cache_id = max_cache_id;
895 
896 		/**
897 		 * On systems without explicit socket descriptions socket
898 		 * is max_cache_id
899 		 */
900 		cpu_data(*id).sock_id = max_cache_id;
901 	}
902 }
903 
904 static void mark_core_ids(struct mdesc_handle *hp, u64 mp,
905 			  int core_id)
906 {
907 	find_back_node_value(hp, mp, "cpu", __mark_core_id, core_id, 10);
908 }
909 
910 static void mark_max_cache_ids(struct mdesc_handle *hp, u64 mp,
911 			       int max_cache_id)
912 {
913 	find_back_node_value(hp, mp, "cpu", __mark_max_cache_id,
914 			     max_cache_id, 10);
915 }
916 
917 static void set_core_ids(struct mdesc_handle *hp)
918 {
919 	int idx;
920 	u64 mp;
921 
922 	idx = 1;
923 
924 	/* Identify unique cores by looking for cpus backpointed to by
925 	 * level 1 instruction caches.
926 	 */
927 	mdesc_for_each_node_by_name(hp, mp, "cache") {
928 		const u64 *level;
929 		const char *type;
930 		int len;
931 
932 		level = mdesc_get_property(hp, mp, "level", NULL);
933 		if (*level != 1)
934 			continue;
935 
936 		type = mdesc_get_property(hp, mp, "type", &len);
937 		if (!of_find_in_proplist(type, "instn", len))
938 			continue;
939 
940 		mark_core_ids(hp, mp, idx);
941 		idx++;
942 	}
943 }
944 
945 static int set_max_cache_ids_by_cache(struct mdesc_handle *hp, int level)
946 {
947 	u64 mp;
948 	int idx = 1;
949 	int fnd = 0;
950 
951 	/**
952 	 * Identify unique highest level of shared cache by looking for cpus
953 	 * backpointed to by shared level N caches.
954 	 */
955 	mdesc_for_each_node_by_name(hp, mp, "cache") {
956 		const u64 *cur_lvl;
957 
958 		cur_lvl = mdesc_get_property(hp, mp, "level", NULL);
959 		if (*cur_lvl != level)
960 			continue;
961 		mark_max_cache_ids(hp, mp, idx);
962 		idx++;
963 		fnd = 1;
964 	}
965 	return fnd;
966 }
967 
968 static void set_sock_ids_by_socket(struct mdesc_handle *hp, u64 mp)
969 {
970 	int idx = 1;
971 
972 	mdesc_for_each_node_by_name(hp, mp, "socket") {
973 		u64 a;
974 
975 		mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
976 			u64 t = mdesc_arc_target(hp, a);
977 			const char *name;
978 			const u64 *id;
979 
980 			name = mdesc_node_name(hp, t);
981 			if (strcmp(name, "cpu"))
982 				continue;
983 
984 			id = mdesc_get_property(hp, t, "id", NULL);
985 			if (*id < num_possible_cpus())
986 				cpu_data(*id).sock_id = idx;
987 		}
988 		idx++;
989 	}
990 }
991 
992 static void set_sock_ids(struct mdesc_handle *hp)
993 {
994 	u64 mp;
995 
996 	/**
997 	 * Find the highest level of shared cache which pre-T7 is also
998 	 * the socket.
999 	 */
1000 	if (!set_max_cache_ids_by_cache(hp, 3))
1001 		set_max_cache_ids_by_cache(hp, 2);
1002 
1003 	/* If machine description exposes sockets data use it.*/
1004 	mp = mdesc_node_by_name(hp, MDESC_NODE_NULL, "sockets");
1005 	if (mp != MDESC_NODE_NULL)
1006 		set_sock_ids_by_socket(hp, mp);
1007 }
1008 
1009 static void mark_proc_ids(struct mdesc_handle *hp, u64 mp, int proc_id)
1010 {
1011 	u64 a;
1012 
1013 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
1014 		u64 t = mdesc_arc_target(hp, a);
1015 		const char *name;
1016 		const u64 *id;
1017 
1018 		name = mdesc_node_name(hp, t);
1019 		if (strcmp(name, "cpu"))
1020 			continue;
1021 
1022 		id = mdesc_get_property(hp, t, "id", NULL);
1023 		if (*id < NR_CPUS)
1024 			cpu_data(*id).proc_id = proc_id;
1025 	}
1026 }
1027 
1028 static void __set_proc_ids(struct mdesc_handle *hp, const char *exec_unit_name)
1029 {
1030 	int idx;
1031 	u64 mp;
1032 
1033 	idx = 0;
1034 	mdesc_for_each_node_by_name(hp, mp, exec_unit_name) {
1035 		const char *type;
1036 		int len;
1037 
1038 		type = mdesc_get_property(hp, mp, "type", &len);
1039 		if (!of_find_in_proplist(type, "int", len) &&
1040 		    !of_find_in_proplist(type, "integer", len))
1041 			continue;
1042 
1043 		mark_proc_ids(hp, mp, idx);
1044 		idx++;
1045 	}
1046 }
1047 
1048 static void set_proc_ids(struct mdesc_handle *hp)
1049 {
1050 	__set_proc_ids(hp, "exec_unit");
1051 	__set_proc_ids(hp, "exec-unit");
1052 }
1053 
1054 static void get_one_mondo_bits(const u64 *p, unsigned int *mask,
1055 			       unsigned long def, unsigned long max)
1056 {
1057 	u64 val;
1058 
1059 	if (!p)
1060 		goto use_default;
1061 	val = *p;
1062 
1063 	if (!val || val >= 64)
1064 		goto use_default;
1065 
1066 	if (val > max)
1067 		val = max;
1068 
1069 	*mask = ((1U << val) * 64U) - 1U;
1070 	return;
1071 
1072 use_default:
1073 	*mask = ((1U << def) * 64U) - 1U;
1074 }
1075 
1076 static void get_mondo_data(struct mdesc_handle *hp, u64 mp,
1077 			   struct trap_per_cpu *tb)
1078 {
1079 	static int printed;
1080 	const u64 *val;
1081 
1082 	val = mdesc_get_property(hp, mp, "q-cpu-mondo-#bits", NULL);
1083 	get_one_mondo_bits(val, &tb->cpu_mondo_qmask, 7, ilog2(max_cpus * 2));
1084 
1085 	val = mdesc_get_property(hp, mp, "q-dev-mondo-#bits", NULL);
1086 	get_one_mondo_bits(val, &tb->dev_mondo_qmask, 7, 8);
1087 
1088 	val = mdesc_get_property(hp, mp, "q-resumable-#bits", NULL);
1089 	get_one_mondo_bits(val, &tb->resum_qmask, 6, 7);
1090 
1091 	val = mdesc_get_property(hp, mp, "q-nonresumable-#bits", NULL);
1092 	get_one_mondo_bits(val, &tb->nonresum_qmask, 2, 2);
1093 	if (!printed++) {
1094 		pr_info("SUN4V: Mondo queue sizes "
1095 			"[cpu(%u) dev(%u) r(%u) nr(%u)]\n",
1096 			tb->cpu_mondo_qmask + 1,
1097 			tb->dev_mondo_qmask + 1,
1098 			tb->resum_qmask + 1,
1099 			tb->nonresum_qmask + 1);
1100 	}
1101 }
1102 
1103 static void *mdesc_iterate_over_cpus(void *(*func)(struct mdesc_handle *, u64, int, void *), void *arg, cpumask_t *mask)
1104 {
1105 	struct mdesc_handle *hp = mdesc_grab();
1106 	void *ret = NULL;
1107 	u64 mp;
1108 
1109 	mdesc_for_each_node_by_name(hp, mp, "cpu") {
1110 		const u64 *id = mdesc_get_property(hp, mp, "id", NULL);
1111 		int cpuid = *id;
1112 
1113 #ifdef CONFIG_SMP
1114 		if (cpuid >= NR_CPUS) {
1115 			printk(KERN_WARNING "Ignoring CPU %d which is "
1116 			       ">= NR_CPUS (%d)\n",
1117 			       cpuid, NR_CPUS);
1118 			continue;
1119 		}
1120 		if (!cpumask_test_cpu(cpuid, mask))
1121 			continue;
1122 #endif
1123 
1124 		ret = func(hp, mp, cpuid, arg);
1125 		if (ret)
1126 			goto out;
1127 	}
1128 out:
1129 	mdesc_release(hp);
1130 	return ret;
1131 }
1132 
1133 static void *record_one_cpu(struct mdesc_handle *hp, u64 mp, int cpuid,
1134 			    void *arg)
1135 {
1136 	ncpus_probed++;
1137 #ifdef CONFIG_SMP
1138 	set_cpu_present(cpuid, true);
1139 #endif
1140 	return NULL;
1141 }
1142 
1143 void mdesc_populate_present_mask(cpumask_t *mask)
1144 {
1145 	if (tlb_type != hypervisor)
1146 		return;
1147 
1148 	ncpus_probed = 0;
1149 	mdesc_iterate_over_cpus(record_one_cpu, NULL, mask);
1150 }
1151 
1152 static void * __init check_one_pgsz(struct mdesc_handle *hp, u64 mp, int cpuid, void *arg)
1153 {
1154 	const u64 *pgsz_prop = mdesc_get_property(hp, mp, "mmu-page-size-list", NULL);
1155 	unsigned long *pgsz_mask = arg;
1156 	u64 val;
1157 
1158 	val = (HV_PGSZ_MASK_8K | HV_PGSZ_MASK_64K |
1159 	       HV_PGSZ_MASK_512K | HV_PGSZ_MASK_4MB);
1160 	if (pgsz_prop)
1161 		val = *pgsz_prop;
1162 
1163 	if (!*pgsz_mask)
1164 		*pgsz_mask = val;
1165 	else
1166 		*pgsz_mask &= val;
1167 	return NULL;
1168 }
1169 
1170 void __init mdesc_get_page_sizes(cpumask_t *mask, unsigned long *pgsz_mask)
1171 {
1172 	*pgsz_mask = 0;
1173 	mdesc_iterate_over_cpus(check_one_pgsz, pgsz_mask, mask);
1174 }
1175 
1176 static void *fill_in_one_cpu(struct mdesc_handle *hp, u64 mp, int cpuid,
1177 			     void *arg)
1178 {
1179 	const u64 *cfreq = mdesc_get_property(hp, mp, "clock-frequency", NULL);
1180 	struct trap_per_cpu *tb;
1181 	cpuinfo_sparc *c;
1182 	u64 a;
1183 
1184 #ifndef CONFIG_SMP
1185 	/* On uniprocessor we only want the values for the
1186 	 * real physical cpu the kernel booted onto, however
1187 	 * cpu_data() only has one entry at index 0.
1188 	 */
1189 	if (cpuid != real_hard_smp_processor_id())
1190 		return NULL;
1191 	cpuid = 0;
1192 #endif
1193 
1194 	c = &cpu_data(cpuid);
1195 	c->clock_tick = *cfreq;
1196 
1197 	tb = &trap_block[cpuid];
1198 	get_mondo_data(hp, mp, tb);
1199 
1200 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
1201 		u64 j, t = mdesc_arc_target(hp, a);
1202 		const char *t_name;
1203 
1204 		t_name = mdesc_node_name(hp, t);
1205 		if (!strcmp(t_name, "cache")) {
1206 			fill_in_one_cache(c, hp, t);
1207 			continue;
1208 		}
1209 
1210 		mdesc_for_each_arc(j, hp, t, MDESC_ARC_TYPE_FWD) {
1211 			u64 n = mdesc_arc_target(hp, j);
1212 			const char *n_name;
1213 
1214 			n_name = mdesc_node_name(hp, n);
1215 			if (!strcmp(n_name, "cache"))
1216 				fill_in_one_cache(c, hp, n);
1217 		}
1218 	}
1219 
1220 	c->core_id = 0;
1221 	c->proc_id = -1;
1222 
1223 	return NULL;
1224 }
1225 
1226 void mdesc_fill_in_cpu_data(cpumask_t *mask)
1227 {
1228 	struct mdesc_handle *hp;
1229 
1230 	mdesc_iterate_over_cpus(fill_in_one_cpu, NULL, mask);
1231 
1232 	hp = mdesc_grab();
1233 
1234 	set_core_ids(hp);
1235 	set_proc_ids(hp);
1236 	set_sock_ids(hp);
1237 
1238 	mdesc_release(hp);
1239 
1240 	smp_fill_in_sib_core_maps();
1241 }
1242 
1243 /* mdesc_open() - Grab a reference to mdesc_handle when /dev/mdesc is
1244  * opened. Hold this reference until /dev/mdesc is closed to ensure
1245  * mdesc data structure is not released underneath us. Store the
1246  * pointer to mdesc structure in private_data for read and seek to use
1247  */
1248 static int mdesc_open(struct inode *inode, struct file *file)
1249 {
1250 	struct mdesc_handle *hp = mdesc_grab();
1251 
1252 	if (!hp)
1253 		return -ENODEV;
1254 
1255 	file->private_data = hp;
1256 
1257 	return 0;
1258 }
1259 
1260 static ssize_t mdesc_read(struct file *file, char __user *buf,
1261 			  size_t len, loff_t *offp)
1262 {
1263 	struct mdesc_handle *hp = file->private_data;
1264 	unsigned char *mdesc;
1265 	int bytes_left, count = len;
1266 
1267 	if (*offp >= hp->handle_size)
1268 		return 0;
1269 
1270 	bytes_left = hp->handle_size - *offp;
1271 	if (count > bytes_left)
1272 		count = bytes_left;
1273 
1274 	mdesc = (unsigned char *)&hp->mdesc;
1275 	mdesc += *offp;
1276 	if (!copy_to_user(buf, mdesc, count)) {
1277 		*offp += count;
1278 		return count;
1279 	} else {
1280 		return -EFAULT;
1281 	}
1282 }
1283 
1284 static loff_t mdesc_llseek(struct file *file, loff_t offset, int whence)
1285 {
1286 	struct mdesc_handle *hp = file->private_data;
1287 
1288 	return no_seek_end_llseek_size(file, offset, whence, hp->handle_size);
1289 }
1290 
1291 /* mdesc_close() - /dev/mdesc is being closed, release the reference to
1292  * mdesc structure.
1293  */
1294 static int mdesc_close(struct inode *inode, struct file *file)
1295 {
1296 	mdesc_release(file->private_data);
1297 	return 0;
1298 }
1299 
1300 static const struct file_operations mdesc_fops = {
1301 	.open    = mdesc_open,
1302 	.read	 = mdesc_read,
1303 	.llseek  = mdesc_llseek,
1304 	.release = mdesc_close,
1305 	.owner	 = THIS_MODULE,
1306 };
1307 
1308 static struct miscdevice mdesc_misc = {
1309 	.minor	= MISC_DYNAMIC_MINOR,
1310 	.name	= "mdesc",
1311 	.fops	= &mdesc_fops,
1312 };
1313 
1314 static int __init mdesc_misc_init(void)
1315 {
1316 	return misc_register(&mdesc_misc);
1317 }
1318 
1319 __initcall(mdesc_misc_init);
1320 
1321 void __init sun4v_mdesc_init(void)
1322 {
1323 	struct mdesc_handle *hp;
1324 	unsigned long len, real_len, status;
1325 
1326 	(void) sun4v_mach_desc(0UL, 0UL, &len);
1327 
1328 	printk("MDESC: Size is %lu bytes.\n", len);
1329 
1330 	hp = mdesc_alloc(len, &memblock_mdesc_ops);
1331 	if (hp == NULL) {
1332 		prom_printf("MDESC: alloc of %lu bytes failed.\n", len);
1333 		prom_halt();
1334 	}
1335 
1336 	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
1337 	if (status != HV_EOK || real_len > len) {
1338 		prom_printf("sun4v_mach_desc fails, err(%lu), "
1339 			    "len(%lu), real_len(%lu)\n",
1340 			    status, len, real_len);
1341 		mdesc_free(hp);
1342 		prom_halt();
1343 	}
1344 
1345 	cur_mdesc = hp;
1346 
1347 	report_platform_properties();
1348 }
1349