xref: /openbmc/linux/arch/sparc/kernel/mdesc.c (revision b627b4ed)
1 /* mdesc.c: Sun4V machine description handling.
2  *
3  * Copyright (C) 2007, 2008 David S. Miller <davem@davemloft.net>
4  */
5 #include <linux/kernel.h>
6 #include <linux/types.h>
7 #include <linux/lmb.h>
8 #include <linux/log2.h>
9 #include <linux/list.h>
10 #include <linux/slab.h>
11 #include <linux/mm.h>
12 #include <linux/miscdevice.h>
13 
14 #include <asm/cpudata.h>
15 #include <asm/hypervisor.h>
16 #include <asm/mdesc.h>
17 #include <asm/prom.h>
18 #include <asm/oplib.h>
19 #include <asm/smp.h>
20 
21 /* Unlike the OBP device tree, the machine description is a full-on
22  * DAG.  An arbitrary number of ARCs are possible from one
23  * node to other nodes and thus we can't use the OBP device_node
24  * data structure to represent these nodes inside of the kernel.
25  *
26  * Actually, it isn't even a DAG, because there are back pointers
27  * which create cycles in the graph.
28  *
29  * mdesc_hdr and mdesc_elem describe the layout of the data structure
30  * we get from the Hypervisor.
31  */
32 struct mdesc_hdr {
33 	u32	version; /* Transport version */
34 	u32	node_sz; /* node block size */
35 	u32	name_sz; /* name block size */
36 	u32	data_sz; /* data block size */
37 } __attribute__((aligned(16)));
38 
39 struct mdesc_elem {
40 	u8	tag;
41 #define MD_LIST_END	0x00
42 #define MD_NODE		0x4e
43 #define MD_NODE_END	0x45
44 #define MD_NOOP		0x20
45 #define MD_PROP_ARC	0x61
46 #define MD_PROP_VAL	0x76
47 #define MD_PROP_STR	0x73
48 #define MD_PROP_DATA	0x64
49 	u8	name_len;
50 	u16	resv;
51 	u32	name_offset;
52 	union {
53 		struct {
54 			u32	data_len;
55 			u32	data_offset;
56 		} data;
57 		u64	val;
58 	} d;
59 };
60 
61 struct mdesc_mem_ops {
62 	struct mdesc_handle *(*alloc)(unsigned int mdesc_size);
63 	void (*free)(struct mdesc_handle *handle);
64 };
65 
66 struct mdesc_handle {
67 	struct list_head	list;
68 	struct mdesc_mem_ops	*mops;
69 	void			*self_base;
70 	atomic_t		refcnt;
71 	unsigned int		handle_size;
72 	struct mdesc_hdr	mdesc;
73 };
74 
75 static void mdesc_handle_init(struct mdesc_handle *hp,
76 			      unsigned int handle_size,
77 			      void *base)
78 {
79 	BUG_ON(((unsigned long)&hp->mdesc) & (16UL - 1));
80 
81 	memset(hp, 0, handle_size);
82 	INIT_LIST_HEAD(&hp->list);
83 	hp->self_base = base;
84 	atomic_set(&hp->refcnt, 1);
85 	hp->handle_size = handle_size;
86 }
87 
88 static struct mdesc_handle * __init mdesc_lmb_alloc(unsigned int mdesc_size)
89 {
90 	unsigned int handle_size, alloc_size;
91 	struct mdesc_handle *hp;
92 	unsigned long paddr;
93 
94 	handle_size = (sizeof(struct mdesc_handle) -
95 		       sizeof(struct mdesc_hdr) +
96 		       mdesc_size);
97 	alloc_size = PAGE_ALIGN(handle_size);
98 
99 	paddr = lmb_alloc(alloc_size, PAGE_SIZE);
100 
101 	hp = NULL;
102 	if (paddr) {
103 		hp = __va(paddr);
104 		mdesc_handle_init(hp, handle_size, hp);
105 	}
106 	return hp;
107 }
108 
109 static void mdesc_lmb_free(struct mdesc_handle *hp)
110 {
111 	unsigned int alloc_size, handle_size = hp->handle_size;
112 	unsigned long start, end;
113 
114 	BUG_ON(atomic_read(&hp->refcnt) != 0);
115 	BUG_ON(!list_empty(&hp->list));
116 
117 	alloc_size = PAGE_ALIGN(handle_size);
118 
119 	start = (unsigned long) hp;
120 	end = start + alloc_size;
121 
122 	while (start < end) {
123 		struct page *p;
124 
125 		p = virt_to_page(start);
126 		ClearPageReserved(p);
127 		__free_page(p);
128 		start += PAGE_SIZE;
129 	}
130 }
131 
132 static struct mdesc_mem_ops lmb_mdesc_ops = {
133 	.alloc = mdesc_lmb_alloc,
134 	.free  = mdesc_lmb_free,
135 };
136 
137 static struct mdesc_handle *mdesc_kmalloc(unsigned int mdesc_size)
138 {
139 	unsigned int handle_size;
140 	void *base;
141 
142 	handle_size = (sizeof(struct mdesc_handle) -
143 		       sizeof(struct mdesc_hdr) +
144 		       mdesc_size);
145 
146 	base = kmalloc(handle_size + 15, GFP_KERNEL | __GFP_NOFAIL);
147 	if (base) {
148 		struct mdesc_handle *hp;
149 		unsigned long addr;
150 
151 		addr = (unsigned long)base;
152 		addr = (addr + 15UL) & ~15UL;
153 		hp = (struct mdesc_handle *) addr;
154 
155 		mdesc_handle_init(hp, handle_size, base);
156 		return hp;
157 	}
158 
159 	return NULL;
160 }
161 
162 static void mdesc_kfree(struct mdesc_handle *hp)
163 {
164 	BUG_ON(atomic_read(&hp->refcnt) != 0);
165 	BUG_ON(!list_empty(&hp->list));
166 
167 	kfree(hp->self_base);
168 }
169 
170 static struct mdesc_mem_ops kmalloc_mdesc_memops = {
171 	.alloc = mdesc_kmalloc,
172 	.free  = mdesc_kfree,
173 };
174 
175 static struct mdesc_handle *mdesc_alloc(unsigned int mdesc_size,
176 					struct mdesc_mem_ops *mops)
177 {
178 	struct mdesc_handle *hp = mops->alloc(mdesc_size);
179 
180 	if (hp)
181 		hp->mops = mops;
182 
183 	return hp;
184 }
185 
186 static void mdesc_free(struct mdesc_handle *hp)
187 {
188 	hp->mops->free(hp);
189 }
190 
191 static struct mdesc_handle *cur_mdesc;
192 static LIST_HEAD(mdesc_zombie_list);
193 static DEFINE_SPINLOCK(mdesc_lock);
194 
195 struct mdesc_handle *mdesc_grab(void)
196 {
197 	struct mdesc_handle *hp;
198 	unsigned long flags;
199 
200 	spin_lock_irqsave(&mdesc_lock, flags);
201 	hp = cur_mdesc;
202 	if (hp)
203 		atomic_inc(&hp->refcnt);
204 	spin_unlock_irqrestore(&mdesc_lock, flags);
205 
206 	return hp;
207 }
208 EXPORT_SYMBOL(mdesc_grab);
209 
210 void mdesc_release(struct mdesc_handle *hp)
211 {
212 	unsigned long flags;
213 
214 	spin_lock_irqsave(&mdesc_lock, flags);
215 	if (atomic_dec_and_test(&hp->refcnt)) {
216 		list_del_init(&hp->list);
217 		hp->mops->free(hp);
218 	}
219 	spin_unlock_irqrestore(&mdesc_lock, flags);
220 }
221 EXPORT_SYMBOL(mdesc_release);
222 
223 static DEFINE_MUTEX(mdesc_mutex);
224 static struct mdesc_notifier_client *client_list;
225 
226 void mdesc_register_notifier(struct mdesc_notifier_client *client)
227 {
228 	u64 node;
229 
230 	mutex_lock(&mdesc_mutex);
231 	client->next = client_list;
232 	client_list = client;
233 
234 	mdesc_for_each_node_by_name(cur_mdesc, node, client->node_name)
235 		client->add(cur_mdesc, node);
236 
237 	mutex_unlock(&mdesc_mutex);
238 }
239 
240 static const u64 *parent_cfg_handle(struct mdesc_handle *hp, u64 node)
241 {
242 	const u64 *id;
243 	u64 a;
244 
245 	id = NULL;
246 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
247 		u64 target;
248 
249 		target = mdesc_arc_target(hp, a);
250 		id = mdesc_get_property(hp, target,
251 					"cfg-handle", NULL);
252 		if (id)
253 			break;
254 	}
255 
256 	return id;
257 }
258 
259 /* Run 'func' on nodes which are in A but not in B.  */
260 static void invoke_on_missing(const char *name,
261 			      struct mdesc_handle *a,
262 			      struct mdesc_handle *b,
263 			      void (*func)(struct mdesc_handle *, u64))
264 {
265 	u64 node;
266 
267 	mdesc_for_each_node_by_name(a, node, name) {
268 		int found = 0, is_vdc_port = 0;
269 		const char *name_prop;
270 		const u64 *id;
271 		u64 fnode;
272 
273 		name_prop = mdesc_get_property(a, node, "name", NULL);
274 		if (name_prop && !strcmp(name_prop, "vdc-port")) {
275 			is_vdc_port = 1;
276 			id = parent_cfg_handle(a, node);
277 		} else
278 			id = mdesc_get_property(a, node, "id", NULL);
279 
280 		if (!id) {
281 			printk(KERN_ERR "MD: Cannot find ID for %s node.\n",
282 			       (name_prop ? name_prop : name));
283 			continue;
284 		}
285 
286 		mdesc_for_each_node_by_name(b, fnode, name) {
287 			const u64 *fid;
288 
289 			if (is_vdc_port) {
290 				name_prop = mdesc_get_property(b, fnode,
291 							       "name", NULL);
292 				if (!name_prop ||
293 				    strcmp(name_prop, "vdc-port"))
294 					continue;
295 				fid = parent_cfg_handle(b, fnode);
296 				if (!fid) {
297 					printk(KERN_ERR "MD: Cannot find ID "
298 					       "for vdc-port node.\n");
299 					continue;
300 				}
301 			} else
302 				fid = mdesc_get_property(b, fnode,
303 							 "id", NULL);
304 
305 			if (*id == *fid) {
306 				found = 1;
307 				break;
308 			}
309 		}
310 		if (!found)
311 			func(a, node);
312 	}
313 }
314 
315 static void notify_one(struct mdesc_notifier_client *p,
316 		       struct mdesc_handle *old_hp,
317 		       struct mdesc_handle *new_hp)
318 {
319 	invoke_on_missing(p->node_name, old_hp, new_hp, p->remove);
320 	invoke_on_missing(p->node_name, new_hp, old_hp, p->add);
321 }
322 
323 static void mdesc_notify_clients(struct mdesc_handle *old_hp,
324 				 struct mdesc_handle *new_hp)
325 {
326 	struct mdesc_notifier_client *p = client_list;
327 
328 	while (p) {
329 		notify_one(p, old_hp, new_hp);
330 		p = p->next;
331 	}
332 }
333 
334 void mdesc_update(void)
335 {
336 	unsigned long len, real_len, status;
337 	struct mdesc_handle *hp, *orig_hp;
338 	unsigned long flags;
339 
340 	mutex_lock(&mdesc_mutex);
341 
342 	(void) sun4v_mach_desc(0UL, 0UL, &len);
343 
344 	hp = mdesc_alloc(len, &kmalloc_mdesc_memops);
345 	if (!hp) {
346 		printk(KERN_ERR "MD: mdesc alloc fails\n");
347 		goto out;
348 	}
349 
350 	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
351 	if (status != HV_EOK || real_len > len) {
352 		printk(KERN_ERR "MD: mdesc reread fails with %lu\n",
353 		       status);
354 		atomic_dec(&hp->refcnt);
355 		mdesc_free(hp);
356 		goto out;
357 	}
358 
359 	spin_lock_irqsave(&mdesc_lock, flags);
360 	orig_hp = cur_mdesc;
361 	cur_mdesc = hp;
362 	spin_unlock_irqrestore(&mdesc_lock, flags);
363 
364 	mdesc_notify_clients(orig_hp, hp);
365 
366 	spin_lock_irqsave(&mdesc_lock, flags);
367 	if (atomic_dec_and_test(&orig_hp->refcnt))
368 		mdesc_free(orig_hp);
369 	else
370 		list_add(&orig_hp->list, &mdesc_zombie_list);
371 	spin_unlock_irqrestore(&mdesc_lock, flags);
372 
373 out:
374 	mutex_unlock(&mdesc_mutex);
375 }
376 
377 static struct mdesc_elem *node_block(struct mdesc_hdr *mdesc)
378 {
379 	return (struct mdesc_elem *) (mdesc + 1);
380 }
381 
382 static void *name_block(struct mdesc_hdr *mdesc)
383 {
384 	return ((void *) node_block(mdesc)) + mdesc->node_sz;
385 }
386 
387 static void *data_block(struct mdesc_hdr *mdesc)
388 {
389 	return ((void *) name_block(mdesc)) + mdesc->name_sz;
390 }
391 
392 u64 mdesc_node_by_name(struct mdesc_handle *hp,
393 		       u64 from_node, const char *name)
394 {
395 	struct mdesc_elem *ep = node_block(&hp->mdesc);
396 	const char *names = name_block(&hp->mdesc);
397 	u64 last_node = hp->mdesc.node_sz / 16;
398 	u64 ret;
399 
400 	if (from_node == MDESC_NODE_NULL) {
401 		ret = from_node = 0;
402 	} else if (from_node >= last_node) {
403 		return MDESC_NODE_NULL;
404 	} else {
405 		ret = ep[from_node].d.val;
406 	}
407 
408 	while (ret < last_node) {
409 		if (ep[ret].tag != MD_NODE)
410 			return MDESC_NODE_NULL;
411 		if (!strcmp(names + ep[ret].name_offset, name))
412 			break;
413 		ret = ep[ret].d.val;
414 	}
415 	if (ret >= last_node)
416 		ret = MDESC_NODE_NULL;
417 	return ret;
418 }
419 EXPORT_SYMBOL(mdesc_node_by_name);
420 
421 const void *mdesc_get_property(struct mdesc_handle *hp, u64 node,
422 			       const char *name, int *lenp)
423 {
424 	const char *names = name_block(&hp->mdesc);
425 	u64 last_node = hp->mdesc.node_sz / 16;
426 	void *data = data_block(&hp->mdesc);
427 	struct mdesc_elem *ep;
428 
429 	if (node == MDESC_NODE_NULL || node >= last_node)
430 		return NULL;
431 
432 	ep = node_block(&hp->mdesc) + node;
433 	ep++;
434 	for (; ep->tag != MD_NODE_END; ep++) {
435 		void *val = NULL;
436 		int len = 0;
437 
438 		switch (ep->tag) {
439 		case MD_PROP_VAL:
440 			val = &ep->d.val;
441 			len = 8;
442 			break;
443 
444 		case MD_PROP_STR:
445 		case MD_PROP_DATA:
446 			val = data + ep->d.data.data_offset;
447 			len = ep->d.data.data_len;
448 			break;
449 
450 		default:
451 			break;
452 		}
453 		if (!val)
454 			continue;
455 
456 		if (!strcmp(names + ep->name_offset, name)) {
457 			if (lenp)
458 				*lenp = len;
459 			return val;
460 		}
461 	}
462 
463 	return NULL;
464 }
465 EXPORT_SYMBOL(mdesc_get_property);
466 
467 u64 mdesc_next_arc(struct mdesc_handle *hp, u64 from, const char *arc_type)
468 {
469 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
470 	const char *names = name_block(&hp->mdesc);
471 	u64 last_node = hp->mdesc.node_sz / 16;
472 
473 	if (from == MDESC_NODE_NULL || from >= last_node)
474 		return MDESC_NODE_NULL;
475 
476 	ep = base + from;
477 
478 	ep++;
479 	for (; ep->tag != MD_NODE_END; ep++) {
480 		if (ep->tag != MD_PROP_ARC)
481 			continue;
482 
483 		if (strcmp(names + ep->name_offset, arc_type))
484 			continue;
485 
486 		return ep - base;
487 	}
488 
489 	return MDESC_NODE_NULL;
490 }
491 EXPORT_SYMBOL(mdesc_next_arc);
492 
493 u64 mdesc_arc_target(struct mdesc_handle *hp, u64 arc)
494 {
495 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
496 
497 	ep = base + arc;
498 
499 	return ep->d.val;
500 }
501 EXPORT_SYMBOL(mdesc_arc_target);
502 
503 const char *mdesc_node_name(struct mdesc_handle *hp, u64 node)
504 {
505 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
506 	const char *names = name_block(&hp->mdesc);
507 	u64 last_node = hp->mdesc.node_sz / 16;
508 
509 	if (node == MDESC_NODE_NULL || node >= last_node)
510 		return NULL;
511 
512 	ep = base + node;
513 	if (ep->tag != MD_NODE)
514 		return NULL;
515 
516 	return names + ep->name_offset;
517 }
518 EXPORT_SYMBOL(mdesc_node_name);
519 
520 static void __init report_platform_properties(void)
521 {
522 	struct mdesc_handle *hp = mdesc_grab();
523 	u64 pn = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
524 	const char *s;
525 	const u64 *v;
526 
527 	if (pn == MDESC_NODE_NULL) {
528 		prom_printf("No platform node in machine-description.\n");
529 		prom_halt();
530 	}
531 
532 	s = mdesc_get_property(hp, pn, "banner-name", NULL);
533 	printk("PLATFORM: banner-name [%s]\n", s);
534 	s = mdesc_get_property(hp, pn, "name", NULL);
535 	printk("PLATFORM: name [%s]\n", s);
536 
537 	v = mdesc_get_property(hp, pn, "hostid", NULL);
538 	if (v)
539 		printk("PLATFORM: hostid [%08llx]\n", *v);
540 	v = mdesc_get_property(hp, pn, "serial#", NULL);
541 	if (v)
542 		printk("PLATFORM: serial# [%08llx]\n", *v);
543 	v = mdesc_get_property(hp, pn, "stick-frequency", NULL);
544 	printk("PLATFORM: stick-frequency [%08llx]\n", *v);
545 	v = mdesc_get_property(hp, pn, "mac-address", NULL);
546 	if (v)
547 		printk("PLATFORM: mac-address [%llx]\n", *v);
548 	v = mdesc_get_property(hp, pn, "watchdog-resolution", NULL);
549 	if (v)
550 		printk("PLATFORM: watchdog-resolution [%llu ms]\n", *v);
551 	v = mdesc_get_property(hp, pn, "watchdog-max-timeout", NULL);
552 	if (v)
553 		printk("PLATFORM: watchdog-max-timeout [%llu ms]\n", *v);
554 	v = mdesc_get_property(hp, pn, "max-cpus", NULL);
555 	if (v)
556 		printk("PLATFORM: max-cpus [%llu]\n", *v);
557 
558 #ifdef CONFIG_SMP
559 	{
560 		int max_cpu, i;
561 
562 		if (v) {
563 			max_cpu = *v;
564 			if (max_cpu > NR_CPUS)
565 				max_cpu = NR_CPUS;
566 		} else {
567 			max_cpu = NR_CPUS;
568 		}
569 		for (i = 0; i < max_cpu; i++)
570 			set_cpu_possible(i, true);
571 	}
572 #endif
573 
574 	mdesc_release(hp);
575 }
576 
577 static void __devinit fill_in_one_cache(cpuinfo_sparc *c,
578 					struct mdesc_handle *hp,
579 					u64 mp)
580 {
581 	const u64 *level = mdesc_get_property(hp, mp, "level", NULL);
582 	const u64 *size = mdesc_get_property(hp, mp, "size", NULL);
583 	const u64 *line_size = mdesc_get_property(hp, mp, "line-size", NULL);
584 	const char *type;
585 	int type_len;
586 
587 	type = mdesc_get_property(hp, mp, "type", &type_len);
588 
589 	switch (*level) {
590 	case 1:
591 		if (of_find_in_proplist(type, "instn", type_len)) {
592 			c->icache_size = *size;
593 			c->icache_line_size = *line_size;
594 		} else if (of_find_in_proplist(type, "data", type_len)) {
595 			c->dcache_size = *size;
596 			c->dcache_line_size = *line_size;
597 		}
598 		break;
599 
600 	case 2:
601 		c->ecache_size = *size;
602 		c->ecache_line_size = *line_size;
603 		break;
604 
605 	default:
606 		break;
607 	}
608 
609 	if (*level == 1) {
610 		u64 a;
611 
612 		mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
613 			u64 target = mdesc_arc_target(hp, a);
614 			const char *name = mdesc_node_name(hp, target);
615 
616 			if (!strcmp(name, "cache"))
617 				fill_in_one_cache(c, hp, target);
618 		}
619 	}
620 }
621 
622 static void __devinit mark_core_ids(struct mdesc_handle *hp, u64 mp,
623 				    int core_id)
624 {
625 	u64 a;
626 
627 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
628 		u64 t = mdesc_arc_target(hp, a);
629 		const char *name;
630 		const u64 *id;
631 
632 		name = mdesc_node_name(hp, t);
633 		if (!strcmp(name, "cpu")) {
634 			id = mdesc_get_property(hp, t, "id", NULL);
635 			if (*id < NR_CPUS)
636 				cpu_data(*id).core_id = core_id;
637 		} else {
638 			u64 j;
639 
640 			mdesc_for_each_arc(j, hp, t, MDESC_ARC_TYPE_BACK) {
641 				u64 n = mdesc_arc_target(hp, j);
642 				const char *n_name;
643 
644 				n_name = mdesc_node_name(hp, n);
645 				if (strcmp(n_name, "cpu"))
646 					continue;
647 
648 				id = mdesc_get_property(hp, n, "id", NULL);
649 				if (*id < NR_CPUS)
650 					cpu_data(*id).core_id = core_id;
651 			}
652 		}
653 	}
654 }
655 
656 static void __devinit set_core_ids(struct mdesc_handle *hp)
657 {
658 	int idx;
659 	u64 mp;
660 
661 	idx = 1;
662 	mdesc_for_each_node_by_name(hp, mp, "cache") {
663 		const u64 *level;
664 		const char *type;
665 		int len;
666 
667 		level = mdesc_get_property(hp, mp, "level", NULL);
668 		if (*level != 1)
669 			continue;
670 
671 		type = mdesc_get_property(hp, mp, "type", &len);
672 		if (!of_find_in_proplist(type, "instn", len))
673 			continue;
674 
675 		mark_core_ids(hp, mp, idx);
676 
677 		idx++;
678 	}
679 }
680 
681 static void __devinit mark_proc_ids(struct mdesc_handle *hp, u64 mp,
682 				    int proc_id)
683 {
684 	u64 a;
685 
686 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
687 		u64 t = mdesc_arc_target(hp, a);
688 		const char *name;
689 		const u64 *id;
690 
691 		name = mdesc_node_name(hp, t);
692 		if (strcmp(name, "cpu"))
693 			continue;
694 
695 		id = mdesc_get_property(hp, t, "id", NULL);
696 		if (*id < NR_CPUS)
697 			cpu_data(*id).proc_id = proc_id;
698 	}
699 }
700 
701 static void __devinit __set_proc_ids(struct mdesc_handle *hp,
702 				     const char *exec_unit_name)
703 {
704 	int idx;
705 	u64 mp;
706 
707 	idx = 0;
708 	mdesc_for_each_node_by_name(hp, mp, exec_unit_name) {
709 		const char *type;
710 		int len;
711 
712 		type = mdesc_get_property(hp, mp, "type", &len);
713 		if (!of_find_in_proplist(type, "int", len) &&
714 		    !of_find_in_proplist(type, "integer", len))
715 			continue;
716 
717 		mark_proc_ids(hp, mp, idx);
718 
719 		idx++;
720 	}
721 }
722 
723 static void __devinit set_proc_ids(struct mdesc_handle *hp)
724 {
725 	__set_proc_ids(hp, "exec_unit");
726 	__set_proc_ids(hp, "exec-unit");
727 }
728 
729 static void __devinit get_one_mondo_bits(const u64 *p, unsigned int *mask,
730 					 unsigned char def)
731 {
732 	u64 val;
733 
734 	if (!p)
735 		goto use_default;
736 	val = *p;
737 
738 	if (!val || val >= 64)
739 		goto use_default;
740 
741 	*mask = ((1U << val) * 64U) - 1U;
742 	return;
743 
744 use_default:
745 	*mask = ((1U << def) * 64U) - 1U;
746 }
747 
748 static void __devinit get_mondo_data(struct mdesc_handle *hp, u64 mp,
749 				     struct trap_per_cpu *tb)
750 {
751 	const u64 *val;
752 
753 	val = mdesc_get_property(hp, mp, "q-cpu-mondo-#bits", NULL);
754 	get_one_mondo_bits(val, &tb->cpu_mondo_qmask, 7);
755 
756 	val = mdesc_get_property(hp, mp, "q-dev-mondo-#bits", NULL);
757 	get_one_mondo_bits(val, &tb->dev_mondo_qmask, 7);
758 
759 	val = mdesc_get_property(hp, mp, "q-resumable-#bits", NULL);
760 	get_one_mondo_bits(val, &tb->resum_qmask, 6);
761 
762 	val = mdesc_get_property(hp, mp, "q-nonresumable-#bits", NULL);
763 	get_one_mondo_bits(val, &tb->nonresum_qmask, 2);
764 }
765 
766 void __cpuinit mdesc_fill_in_cpu_data(cpumask_t mask)
767 {
768 	struct mdesc_handle *hp = mdesc_grab();
769 	u64 mp;
770 
771 	ncpus_probed = 0;
772 	mdesc_for_each_node_by_name(hp, mp, "cpu") {
773 		const u64 *id = mdesc_get_property(hp, mp, "id", NULL);
774 		const u64 *cfreq = mdesc_get_property(hp, mp, "clock-frequency", NULL);
775 		struct trap_per_cpu *tb;
776 		cpuinfo_sparc *c;
777 		int cpuid;
778 		u64 a;
779 
780 		ncpus_probed++;
781 
782 		cpuid = *id;
783 
784 #ifdef CONFIG_SMP
785 		if (cpuid >= NR_CPUS) {
786 			printk(KERN_WARNING "Ignoring CPU %d which is "
787 			       ">= NR_CPUS (%d)\n",
788 			       cpuid, NR_CPUS);
789 			continue;
790 		}
791 		if (!cpu_isset(cpuid, mask))
792 			continue;
793 #else
794 		/* On uniprocessor we only want the values for the
795 		 * real physical cpu the kernel booted onto, however
796 		 * cpu_data() only has one entry at index 0.
797 		 */
798 		if (cpuid != real_hard_smp_processor_id())
799 			continue;
800 		cpuid = 0;
801 #endif
802 
803 		c = &cpu_data(cpuid);
804 		c->clock_tick = *cfreq;
805 
806 		tb = &trap_block[cpuid];
807 		get_mondo_data(hp, mp, tb);
808 
809 		mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
810 			u64 j, t = mdesc_arc_target(hp, a);
811 			const char *t_name;
812 
813 			t_name = mdesc_node_name(hp, t);
814 			if (!strcmp(t_name, "cache")) {
815 				fill_in_one_cache(c, hp, t);
816 				continue;
817 			}
818 
819 			mdesc_for_each_arc(j, hp, t, MDESC_ARC_TYPE_FWD) {
820 				u64 n = mdesc_arc_target(hp, j);
821 				const char *n_name;
822 
823 				n_name = mdesc_node_name(hp, n);
824 				if (!strcmp(n_name, "cache"))
825 					fill_in_one_cache(c, hp, n);
826 			}
827 		}
828 
829 #ifdef CONFIG_SMP
830 		cpu_set(cpuid, cpu_present_map);
831 #endif
832 
833 		c->core_id = 0;
834 		c->proc_id = -1;
835 	}
836 
837 #ifdef CONFIG_SMP
838 	sparc64_multi_core = 1;
839 #endif
840 
841 	set_core_ids(hp);
842 	set_proc_ids(hp);
843 
844 	smp_fill_in_sib_core_maps();
845 
846 	mdesc_release(hp);
847 }
848 
849 static ssize_t mdesc_read(struct file *file, char __user *buf,
850 			  size_t len, loff_t *offp)
851 {
852 	struct mdesc_handle *hp = mdesc_grab();
853 	int err;
854 
855 	if (!hp)
856 		return -ENODEV;
857 
858 	err = hp->handle_size;
859 	if (len < hp->handle_size)
860 		err = -EMSGSIZE;
861 	else if (copy_to_user(buf, &hp->mdesc, hp->handle_size))
862 		err = -EFAULT;
863 	mdesc_release(hp);
864 
865 	return err;
866 }
867 
868 static const struct file_operations mdesc_fops = {
869 	.read	= mdesc_read,
870 	.owner	= THIS_MODULE,
871 };
872 
873 static struct miscdevice mdesc_misc = {
874 	.minor	= MISC_DYNAMIC_MINOR,
875 	.name	= "mdesc",
876 	.fops	= &mdesc_fops,
877 };
878 
879 static int __init mdesc_misc_init(void)
880 {
881 	return misc_register(&mdesc_misc);
882 }
883 
884 __initcall(mdesc_misc_init);
885 
886 void __init sun4v_mdesc_init(void)
887 {
888 	struct mdesc_handle *hp;
889 	unsigned long len, real_len, status;
890 	cpumask_t mask;
891 
892 	(void) sun4v_mach_desc(0UL, 0UL, &len);
893 
894 	printk("MDESC: Size is %lu bytes.\n", len);
895 
896 	hp = mdesc_alloc(len, &lmb_mdesc_ops);
897 	if (hp == NULL) {
898 		prom_printf("MDESC: alloc of %lu bytes failed.\n", len);
899 		prom_halt();
900 	}
901 
902 	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
903 	if (status != HV_EOK || real_len > len) {
904 		prom_printf("sun4v_mach_desc fails, err(%lu), "
905 			    "len(%lu), real_len(%lu)\n",
906 			    status, len, real_len);
907 		mdesc_free(hp);
908 		prom_halt();
909 	}
910 
911 	cur_mdesc = hp;
912 
913 	report_platform_properties();
914 
915 	cpus_setall(mask);
916 	mdesc_fill_in_cpu_data(mask);
917 }
918