xref: /linux/arch/sparc/kernel/mdesc.c (revision 7c43185138cf523b0810ffd2c9e18e2ecb356730)
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/memblock.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 #include <linux/bootmem.h>
14 
15 #include <asm/cpudata.h>
16 #include <asm/hypervisor.h>
17 #include <asm/mdesc.h>
18 #include <asm/prom.h>
19 #include <asm/oplib.h>
20 #include <asm/smp.h>
21 
22 /* Unlike the OBP device tree, the machine description is a full-on
23  * DAG.  An arbitrary number of ARCs are possible from one
24  * node to other nodes and thus we can't use the OBP device_node
25  * data structure to represent these nodes inside of the kernel.
26  *
27  * Actually, it isn't even a DAG, because there are back pointers
28  * which create cycles in the graph.
29  *
30  * mdesc_hdr and mdesc_elem describe the layout of the data structure
31  * we get from the Hypervisor.
32  */
33 struct mdesc_hdr {
34 	u32	version; /* Transport version */
35 	u32	node_sz; /* node block size */
36 	u32	name_sz; /* name block size */
37 	u32	data_sz; /* data block size */
38 } __attribute__((aligned(16)));
39 
40 struct mdesc_elem {
41 	u8	tag;
42 #define MD_LIST_END	0x00
43 #define MD_NODE		0x4e
44 #define MD_NODE_END	0x45
45 #define MD_NOOP		0x20
46 #define MD_PROP_ARC	0x61
47 #define MD_PROP_VAL	0x76
48 #define MD_PROP_STR	0x73
49 #define MD_PROP_DATA	0x64
50 	u8	name_len;
51 	u16	resv;
52 	u32	name_offset;
53 	union {
54 		struct {
55 			u32	data_len;
56 			u32	data_offset;
57 		} data;
58 		u64	val;
59 	} d;
60 };
61 
62 struct mdesc_mem_ops {
63 	struct mdesc_handle *(*alloc)(unsigned int mdesc_size);
64 	void (*free)(struct mdesc_handle *handle);
65 };
66 
67 struct mdesc_handle {
68 	struct list_head	list;
69 	struct mdesc_mem_ops	*mops;
70 	void			*self_base;
71 	atomic_t		refcnt;
72 	unsigned int		handle_size;
73 	struct mdesc_hdr	mdesc;
74 };
75 
76 static void mdesc_handle_init(struct mdesc_handle *hp,
77 			      unsigned int handle_size,
78 			      void *base)
79 {
80 	BUG_ON(((unsigned long)&hp->mdesc) & (16UL - 1));
81 
82 	memset(hp, 0, handle_size);
83 	INIT_LIST_HEAD(&hp->list);
84 	hp->self_base = base;
85 	atomic_set(&hp->refcnt, 1);
86 	hp->handle_size = handle_size;
87 }
88 
89 static struct mdesc_handle * __init mdesc_memblock_alloc(unsigned int mdesc_size)
90 {
91 	unsigned int handle_size, alloc_size;
92 	struct mdesc_handle *hp;
93 	unsigned long paddr;
94 
95 	handle_size = (sizeof(struct mdesc_handle) -
96 		       sizeof(struct mdesc_hdr) +
97 		       mdesc_size);
98 	alloc_size = PAGE_ALIGN(handle_size);
99 
100 	paddr = memblock_alloc(alloc_size, PAGE_SIZE);
101 
102 	hp = NULL;
103 	if (paddr) {
104 		hp = __va(paddr);
105 		mdesc_handle_init(hp, handle_size, hp);
106 	}
107 	return hp;
108 }
109 
110 static void __init mdesc_memblock_free(struct mdesc_handle *hp)
111 {
112 	unsigned int alloc_size;
113 	unsigned long start;
114 
115 	BUG_ON(atomic_read(&hp->refcnt) != 0);
116 	BUG_ON(!list_empty(&hp->list));
117 
118 	alloc_size = PAGE_ALIGN(hp->handle_size);
119 	start = __pa(hp);
120 	free_bootmem_late(start, alloc_size);
121 }
122 
123 static struct mdesc_mem_ops memblock_mdesc_ops = {
124 	.alloc = mdesc_memblock_alloc,
125 	.free  = mdesc_memblock_free,
126 };
127 
128 static struct mdesc_handle *mdesc_kmalloc(unsigned int mdesc_size)
129 {
130 	unsigned int handle_size;
131 	void *base;
132 
133 	handle_size = (sizeof(struct mdesc_handle) -
134 		       sizeof(struct mdesc_hdr) +
135 		       mdesc_size);
136 
137 	base = kmalloc(handle_size + 15, GFP_KERNEL | __GFP_NOFAIL);
138 	if (base) {
139 		struct mdesc_handle *hp;
140 		unsigned long addr;
141 
142 		addr = (unsigned long)base;
143 		addr = (addr + 15UL) & ~15UL;
144 		hp = (struct mdesc_handle *) addr;
145 
146 		mdesc_handle_init(hp, handle_size, base);
147 		return hp;
148 	}
149 
150 	return NULL;
151 }
152 
153 static void mdesc_kfree(struct mdesc_handle *hp)
154 {
155 	BUG_ON(atomic_read(&hp->refcnt) != 0);
156 	BUG_ON(!list_empty(&hp->list));
157 
158 	kfree(hp->self_base);
159 }
160 
161 static struct mdesc_mem_ops kmalloc_mdesc_memops = {
162 	.alloc = mdesc_kmalloc,
163 	.free  = mdesc_kfree,
164 };
165 
166 static struct mdesc_handle *mdesc_alloc(unsigned int mdesc_size,
167 					struct mdesc_mem_ops *mops)
168 {
169 	struct mdesc_handle *hp = mops->alloc(mdesc_size);
170 
171 	if (hp)
172 		hp->mops = mops;
173 
174 	return hp;
175 }
176 
177 static void mdesc_free(struct mdesc_handle *hp)
178 {
179 	hp->mops->free(hp);
180 }
181 
182 static struct mdesc_handle *cur_mdesc;
183 static LIST_HEAD(mdesc_zombie_list);
184 static DEFINE_SPINLOCK(mdesc_lock);
185 
186 struct mdesc_handle *mdesc_grab(void)
187 {
188 	struct mdesc_handle *hp;
189 	unsigned long flags;
190 
191 	spin_lock_irqsave(&mdesc_lock, flags);
192 	hp = cur_mdesc;
193 	if (hp)
194 		atomic_inc(&hp->refcnt);
195 	spin_unlock_irqrestore(&mdesc_lock, flags);
196 
197 	return hp;
198 }
199 EXPORT_SYMBOL(mdesc_grab);
200 
201 void mdesc_release(struct mdesc_handle *hp)
202 {
203 	unsigned long flags;
204 
205 	spin_lock_irqsave(&mdesc_lock, flags);
206 	if (atomic_dec_and_test(&hp->refcnt)) {
207 		list_del_init(&hp->list);
208 		hp->mops->free(hp);
209 	}
210 	spin_unlock_irqrestore(&mdesc_lock, flags);
211 }
212 EXPORT_SYMBOL(mdesc_release);
213 
214 static DEFINE_MUTEX(mdesc_mutex);
215 static struct mdesc_notifier_client *client_list;
216 
217 void mdesc_register_notifier(struct mdesc_notifier_client *client)
218 {
219 	u64 node;
220 
221 	mutex_lock(&mdesc_mutex);
222 	client->next = client_list;
223 	client_list = client;
224 
225 	mdesc_for_each_node_by_name(cur_mdesc, node, client->node_name)
226 		client->add(cur_mdesc, node);
227 
228 	mutex_unlock(&mdesc_mutex);
229 }
230 
231 static const u64 *parent_cfg_handle(struct mdesc_handle *hp, u64 node)
232 {
233 	const u64 *id;
234 	u64 a;
235 
236 	id = NULL;
237 	mdesc_for_each_arc(a, hp, node, MDESC_ARC_TYPE_BACK) {
238 		u64 target;
239 
240 		target = mdesc_arc_target(hp, a);
241 		id = mdesc_get_property(hp, target,
242 					"cfg-handle", NULL);
243 		if (id)
244 			break;
245 	}
246 
247 	return id;
248 }
249 
250 /* Run 'func' on nodes which are in A but not in B.  */
251 static void invoke_on_missing(const char *name,
252 			      struct mdesc_handle *a,
253 			      struct mdesc_handle *b,
254 			      void (*func)(struct mdesc_handle *, u64))
255 {
256 	u64 node;
257 
258 	mdesc_for_each_node_by_name(a, node, name) {
259 		int found = 0, is_vdc_port = 0;
260 		const char *name_prop;
261 		const u64 *id;
262 		u64 fnode;
263 
264 		name_prop = mdesc_get_property(a, node, "name", NULL);
265 		if (name_prop && !strcmp(name_prop, "vdc-port")) {
266 			is_vdc_port = 1;
267 			id = parent_cfg_handle(a, node);
268 		} else
269 			id = mdesc_get_property(a, node, "id", NULL);
270 
271 		if (!id) {
272 			printk(KERN_ERR "MD: Cannot find ID for %s node.\n",
273 			       (name_prop ? name_prop : name));
274 			continue;
275 		}
276 
277 		mdesc_for_each_node_by_name(b, fnode, name) {
278 			const u64 *fid;
279 
280 			if (is_vdc_port) {
281 				name_prop = mdesc_get_property(b, fnode,
282 							       "name", NULL);
283 				if (!name_prop ||
284 				    strcmp(name_prop, "vdc-port"))
285 					continue;
286 				fid = parent_cfg_handle(b, fnode);
287 				if (!fid) {
288 					printk(KERN_ERR "MD: Cannot find ID "
289 					       "for vdc-port node.\n");
290 					continue;
291 				}
292 			} else
293 				fid = mdesc_get_property(b, fnode,
294 							 "id", NULL);
295 
296 			if (*id == *fid) {
297 				found = 1;
298 				break;
299 			}
300 		}
301 		if (!found)
302 			func(a, node);
303 	}
304 }
305 
306 static void notify_one(struct mdesc_notifier_client *p,
307 		       struct mdesc_handle *old_hp,
308 		       struct mdesc_handle *new_hp)
309 {
310 	invoke_on_missing(p->node_name, old_hp, new_hp, p->remove);
311 	invoke_on_missing(p->node_name, new_hp, old_hp, p->add);
312 }
313 
314 static void mdesc_notify_clients(struct mdesc_handle *old_hp,
315 				 struct mdesc_handle *new_hp)
316 {
317 	struct mdesc_notifier_client *p = client_list;
318 
319 	while (p) {
320 		notify_one(p, old_hp, new_hp);
321 		p = p->next;
322 	}
323 }
324 
325 void mdesc_update(void)
326 {
327 	unsigned long len, real_len, status;
328 	struct mdesc_handle *hp, *orig_hp;
329 	unsigned long flags;
330 
331 	mutex_lock(&mdesc_mutex);
332 
333 	(void) sun4v_mach_desc(0UL, 0UL, &len);
334 
335 	hp = mdesc_alloc(len, &kmalloc_mdesc_memops);
336 	if (!hp) {
337 		printk(KERN_ERR "MD: mdesc alloc fails\n");
338 		goto out;
339 	}
340 
341 	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
342 	if (status != HV_EOK || real_len > len) {
343 		printk(KERN_ERR "MD: mdesc reread fails with %lu\n",
344 		       status);
345 		atomic_dec(&hp->refcnt);
346 		mdesc_free(hp);
347 		goto out;
348 	}
349 
350 	spin_lock_irqsave(&mdesc_lock, flags);
351 	orig_hp = cur_mdesc;
352 	cur_mdesc = hp;
353 	spin_unlock_irqrestore(&mdesc_lock, flags);
354 
355 	mdesc_notify_clients(orig_hp, hp);
356 
357 	spin_lock_irqsave(&mdesc_lock, flags);
358 	if (atomic_dec_and_test(&orig_hp->refcnt))
359 		mdesc_free(orig_hp);
360 	else
361 		list_add(&orig_hp->list, &mdesc_zombie_list);
362 	spin_unlock_irqrestore(&mdesc_lock, flags);
363 
364 out:
365 	mutex_unlock(&mdesc_mutex);
366 }
367 
368 static struct mdesc_elem *node_block(struct mdesc_hdr *mdesc)
369 {
370 	return (struct mdesc_elem *) (mdesc + 1);
371 }
372 
373 static void *name_block(struct mdesc_hdr *mdesc)
374 {
375 	return ((void *) node_block(mdesc)) + mdesc->node_sz;
376 }
377 
378 static void *data_block(struct mdesc_hdr *mdesc)
379 {
380 	return ((void *) name_block(mdesc)) + mdesc->name_sz;
381 }
382 
383 u64 mdesc_node_by_name(struct mdesc_handle *hp,
384 		       u64 from_node, const char *name)
385 {
386 	struct mdesc_elem *ep = node_block(&hp->mdesc);
387 	const char *names = name_block(&hp->mdesc);
388 	u64 last_node = hp->mdesc.node_sz / 16;
389 	u64 ret;
390 
391 	if (from_node == MDESC_NODE_NULL) {
392 		ret = from_node = 0;
393 	} else if (from_node >= last_node) {
394 		return MDESC_NODE_NULL;
395 	} else {
396 		ret = ep[from_node].d.val;
397 	}
398 
399 	while (ret < last_node) {
400 		if (ep[ret].tag != MD_NODE)
401 			return MDESC_NODE_NULL;
402 		if (!strcmp(names + ep[ret].name_offset, name))
403 			break;
404 		ret = ep[ret].d.val;
405 	}
406 	if (ret >= last_node)
407 		ret = MDESC_NODE_NULL;
408 	return ret;
409 }
410 EXPORT_SYMBOL(mdesc_node_by_name);
411 
412 const void *mdesc_get_property(struct mdesc_handle *hp, u64 node,
413 			       const char *name, int *lenp)
414 {
415 	const char *names = name_block(&hp->mdesc);
416 	u64 last_node = hp->mdesc.node_sz / 16;
417 	void *data = data_block(&hp->mdesc);
418 	struct mdesc_elem *ep;
419 
420 	if (node == MDESC_NODE_NULL || node >= last_node)
421 		return NULL;
422 
423 	ep = node_block(&hp->mdesc) + node;
424 	ep++;
425 	for (; ep->tag != MD_NODE_END; ep++) {
426 		void *val = NULL;
427 		int len = 0;
428 
429 		switch (ep->tag) {
430 		case MD_PROP_VAL:
431 			val = &ep->d.val;
432 			len = 8;
433 			break;
434 
435 		case MD_PROP_STR:
436 		case MD_PROP_DATA:
437 			val = data + ep->d.data.data_offset;
438 			len = ep->d.data.data_len;
439 			break;
440 
441 		default:
442 			break;
443 		}
444 		if (!val)
445 			continue;
446 
447 		if (!strcmp(names + ep->name_offset, name)) {
448 			if (lenp)
449 				*lenp = len;
450 			return val;
451 		}
452 	}
453 
454 	return NULL;
455 }
456 EXPORT_SYMBOL(mdesc_get_property);
457 
458 u64 mdesc_next_arc(struct mdesc_handle *hp, u64 from, const char *arc_type)
459 {
460 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
461 	const char *names = name_block(&hp->mdesc);
462 	u64 last_node = hp->mdesc.node_sz / 16;
463 
464 	if (from == MDESC_NODE_NULL || from >= last_node)
465 		return MDESC_NODE_NULL;
466 
467 	ep = base + from;
468 
469 	ep++;
470 	for (; ep->tag != MD_NODE_END; ep++) {
471 		if (ep->tag != MD_PROP_ARC)
472 			continue;
473 
474 		if (strcmp(names + ep->name_offset, arc_type))
475 			continue;
476 
477 		return ep - base;
478 	}
479 
480 	return MDESC_NODE_NULL;
481 }
482 EXPORT_SYMBOL(mdesc_next_arc);
483 
484 u64 mdesc_arc_target(struct mdesc_handle *hp, u64 arc)
485 {
486 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
487 
488 	ep = base + arc;
489 
490 	return ep->d.val;
491 }
492 EXPORT_SYMBOL(mdesc_arc_target);
493 
494 const char *mdesc_node_name(struct mdesc_handle *hp, u64 node)
495 {
496 	struct mdesc_elem *ep, *base = node_block(&hp->mdesc);
497 	const char *names = name_block(&hp->mdesc);
498 	u64 last_node = hp->mdesc.node_sz / 16;
499 
500 	if (node == MDESC_NODE_NULL || node >= last_node)
501 		return NULL;
502 
503 	ep = base + node;
504 	if (ep->tag != MD_NODE)
505 		return NULL;
506 
507 	return names + ep->name_offset;
508 }
509 EXPORT_SYMBOL(mdesc_node_name);
510 
511 static u64 max_cpus = 64;
512 
513 static void __init report_platform_properties(void)
514 {
515 	struct mdesc_handle *hp = mdesc_grab();
516 	u64 pn = mdesc_node_by_name(hp, MDESC_NODE_NULL, "platform");
517 	const char *s;
518 	const u64 *v;
519 
520 	if (pn == MDESC_NODE_NULL) {
521 		prom_printf("No platform node in machine-description.\n");
522 		prom_halt();
523 	}
524 
525 	s = mdesc_get_property(hp, pn, "banner-name", NULL);
526 	printk("PLATFORM: banner-name [%s]\n", s);
527 	s = mdesc_get_property(hp, pn, "name", NULL);
528 	printk("PLATFORM: name [%s]\n", s);
529 
530 	v = mdesc_get_property(hp, pn, "hostid", NULL);
531 	if (v)
532 		printk("PLATFORM: hostid [%08llx]\n", *v);
533 	v = mdesc_get_property(hp, pn, "serial#", NULL);
534 	if (v)
535 		printk("PLATFORM: serial# [%08llx]\n", *v);
536 	v = mdesc_get_property(hp, pn, "stick-frequency", NULL);
537 	printk("PLATFORM: stick-frequency [%08llx]\n", *v);
538 	v = mdesc_get_property(hp, pn, "mac-address", NULL);
539 	if (v)
540 		printk("PLATFORM: mac-address [%llx]\n", *v);
541 	v = mdesc_get_property(hp, pn, "watchdog-resolution", NULL);
542 	if (v)
543 		printk("PLATFORM: watchdog-resolution [%llu ms]\n", *v);
544 	v = mdesc_get_property(hp, pn, "watchdog-max-timeout", NULL);
545 	if (v)
546 		printk("PLATFORM: watchdog-max-timeout [%llu ms]\n", *v);
547 	v = mdesc_get_property(hp, pn, "max-cpus", NULL);
548 	if (v) {
549 		max_cpus = *v;
550 		printk("PLATFORM: max-cpus [%llu]\n", max_cpus);
551 	}
552 
553 #ifdef CONFIG_SMP
554 	{
555 		int max_cpu, i;
556 
557 		if (v) {
558 			max_cpu = *v;
559 			if (max_cpu > NR_CPUS)
560 				max_cpu = NR_CPUS;
561 		} else {
562 			max_cpu = NR_CPUS;
563 		}
564 		for (i = 0; i < max_cpu; i++)
565 			set_cpu_possible(i, true);
566 	}
567 #endif
568 
569 	mdesc_release(hp);
570 }
571 
572 static void __cpuinit fill_in_one_cache(cpuinfo_sparc *c,
573 					struct mdesc_handle *hp,
574 					u64 mp)
575 {
576 	const u64 *level = mdesc_get_property(hp, mp, "level", NULL);
577 	const u64 *size = mdesc_get_property(hp, mp, "size", NULL);
578 	const u64 *line_size = mdesc_get_property(hp, mp, "line-size", NULL);
579 	const char *type;
580 	int type_len;
581 
582 	type = mdesc_get_property(hp, mp, "type", &type_len);
583 
584 	switch (*level) {
585 	case 1:
586 		if (of_find_in_proplist(type, "instn", type_len)) {
587 			c->icache_size = *size;
588 			c->icache_line_size = *line_size;
589 		} else if (of_find_in_proplist(type, "data", type_len)) {
590 			c->dcache_size = *size;
591 			c->dcache_line_size = *line_size;
592 		}
593 		break;
594 
595 	case 2:
596 		c->ecache_size = *size;
597 		c->ecache_line_size = *line_size;
598 		break;
599 
600 	default:
601 		break;
602 	}
603 
604 	if (*level == 1) {
605 		u64 a;
606 
607 		mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
608 			u64 target = mdesc_arc_target(hp, a);
609 			const char *name = mdesc_node_name(hp, target);
610 
611 			if (!strcmp(name, "cache"))
612 				fill_in_one_cache(c, hp, target);
613 		}
614 	}
615 }
616 
617 static void __cpuinit mark_core_ids(struct mdesc_handle *hp, u64 mp, int core_id)
618 {
619 	u64 a;
620 
621 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
622 		u64 t = mdesc_arc_target(hp, a);
623 		const char *name;
624 		const u64 *id;
625 
626 		name = mdesc_node_name(hp, t);
627 		if (!strcmp(name, "cpu")) {
628 			id = mdesc_get_property(hp, t, "id", NULL);
629 			if (*id < NR_CPUS)
630 				cpu_data(*id).core_id = core_id;
631 		} else {
632 			u64 j;
633 
634 			mdesc_for_each_arc(j, hp, t, MDESC_ARC_TYPE_BACK) {
635 				u64 n = mdesc_arc_target(hp, j);
636 				const char *n_name;
637 
638 				n_name = mdesc_node_name(hp, n);
639 				if (strcmp(n_name, "cpu"))
640 					continue;
641 
642 				id = mdesc_get_property(hp, n, "id", NULL);
643 				if (*id < NR_CPUS)
644 					cpu_data(*id).core_id = core_id;
645 			}
646 		}
647 	}
648 }
649 
650 static void __cpuinit set_core_ids(struct mdesc_handle *hp)
651 {
652 	int idx;
653 	u64 mp;
654 
655 	idx = 1;
656 	mdesc_for_each_node_by_name(hp, mp, "cache") {
657 		const u64 *level;
658 		const char *type;
659 		int len;
660 
661 		level = mdesc_get_property(hp, mp, "level", NULL);
662 		if (*level != 1)
663 			continue;
664 
665 		type = mdesc_get_property(hp, mp, "type", &len);
666 		if (!of_find_in_proplist(type, "instn", len))
667 			continue;
668 
669 		mark_core_ids(hp, mp, idx);
670 
671 		idx++;
672 	}
673 }
674 
675 static void __cpuinit mark_proc_ids(struct mdesc_handle *hp, u64 mp, int proc_id)
676 {
677 	u64 a;
678 
679 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_BACK) {
680 		u64 t = mdesc_arc_target(hp, a);
681 		const char *name;
682 		const u64 *id;
683 
684 		name = mdesc_node_name(hp, t);
685 		if (strcmp(name, "cpu"))
686 			continue;
687 
688 		id = mdesc_get_property(hp, t, "id", NULL);
689 		if (*id < NR_CPUS)
690 			cpu_data(*id).proc_id = proc_id;
691 	}
692 }
693 
694 static void __cpuinit __set_proc_ids(struct mdesc_handle *hp, const char *exec_unit_name)
695 {
696 	int idx;
697 	u64 mp;
698 
699 	idx = 0;
700 	mdesc_for_each_node_by_name(hp, mp, exec_unit_name) {
701 		const char *type;
702 		int len;
703 
704 		type = mdesc_get_property(hp, mp, "type", &len);
705 		if (!of_find_in_proplist(type, "int", len) &&
706 		    !of_find_in_proplist(type, "integer", len))
707 			continue;
708 
709 		mark_proc_ids(hp, mp, idx);
710 
711 		idx++;
712 	}
713 }
714 
715 static void __cpuinit set_proc_ids(struct mdesc_handle *hp)
716 {
717 	__set_proc_ids(hp, "exec_unit");
718 	__set_proc_ids(hp, "exec-unit");
719 }
720 
721 static void __cpuinit get_one_mondo_bits(const u64 *p, unsigned int *mask,
722 					 unsigned long def, unsigned long max)
723 {
724 	u64 val;
725 
726 	if (!p)
727 		goto use_default;
728 	val = *p;
729 
730 	if (!val || val >= 64)
731 		goto use_default;
732 
733 	if (val > max)
734 		val = max;
735 
736 	*mask = ((1U << val) * 64U) - 1U;
737 	return;
738 
739 use_default:
740 	*mask = ((1U << def) * 64U) - 1U;
741 }
742 
743 static void __cpuinit get_mondo_data(struct mdesc_handle *hp, u64 mp,
744 				     struct trap_per_cpu *tb)
745 {
746 	static int printed;
747 	const u64 *val;
748 
749 	val = mdesc_get_property(hp, mp, "q-cpu-mondo-#bits", NULL);
750 	get_one_mondo_bits(val, &tb->cpu_mondo_qmask, 7, ilog2(max_cpus * 2));
751 
752 	val = mdesc_get_property(hp, mp, "q-dev-mondo-#bits", NULL);
753 	get_one_mondo_bits(val, &tb->dev_mondo_qmask, 7, 8);
754 
755 	val = mdesc_get_property(hp, mp, "q-resumable-#bits", NULL);
756 	get_one_mondo_bits(val, &tb->resum_qmask, 6, 7);
757 
758 	val = mdesc_get_property(hp, mp, "q-nonresumable-#bits", NULL);
759 	get_one_mondo_bits(val, &tb->nonresum_qmask, 2, 2);
760 	if (!printed++) {
761 		pr_info("SUN4V: Mondo queue sizes "
762 			"[cpu(%u) dev(%u) r(%u) nr(%u)]\n",
763 			tb->cpu_mondo_qmask + 1,
764 			tb->dev_mondo_qmask + 1,
765 			tb->resum_qmask + 1,
766 			tb->nonresum_qmask + 1);
767 	}
768 }
769 
770 static void * __cpuinit mdesc_iterate_over_cpus(void *(*func)(struct mdesc_handle *, u64, int, void *), void *arg, cpumask_t *mask)
771 {
772 	struct mdesc_handle *hp = mdesc_grab();
773 	void *ret = NULL;
774 	u64 mp;
775 
776 	mdesc_for_each_node_by_name(hp, mp, "cpu") {
777 		const u64 *id = mdesc_get_property(hp, mp, "id", NULL);
778 		int cpuid = *id;
779 
780 #ifdef CONFIG_SMP
781 		if (cpuid >= NR_CPUS) {
782 			printk(KERN_WARNING "Ignoring CPU %d which is "
783 			       ">= NR_CPUS (%d)\n",
784 			       cpuid, NR_CPUS);
785 			continue;
786 		}
787 		if (!cpumask_test_cpu(cpuid, mask))
788 			continue;
789 #endif
790 
791 		ret = func(hp, mp, cpuid, arg);
792 		if (ret)
793 			goto out;
794 	}
795 out:
796 	mdesc_release(hp);
797 	return ret;
798 }
799 
800 static void * __cpuinit record_one_cpu(struct mdesc_handle *hp, u64 mp, int cpuid, void *arg)
801 {
802 	ncpus_probed++;
803 #ifdef CONFIG_SMP
804 	set_cpu_present(cpuid, true);
805 #endif
806 	return NULL;
807 }
808 
809 void __cpuinit mdesc_populate_present_mask(cpumask_t *mask)
810 {
811 	if (tlb_type != hypervisor)
812 		return;
813 
814 	ncpus_probed = 0;
815 	mdesc_iterate_over_cpus(record_one_cpu, NULL, mask);
816 }
817 
818 static void * __cpuinit fill_in_one_cpu(struct mdesc_handle *hp, u64 mp, int cpuid, void *arg)
819 {
820 	const u64 *cfreq = mdesc_get_property(hp, mp, "clock-frequency", NULL);
821 	struct trap_per_cpu *tb;
822 	cpuinfo_sparc *c;
823 	u64 a;
824 
825 #ifndef CONFIG_SMP
826 	/* On uniprocessor we only want the values for the
827 	 * real physical cpu the kernel booted onto, however
828 	 * cpu_data() only has one entry at index 0.
829 	 */
830 	if (cpuid != real_hard_smp_processor_id())
831 		return NULL;
832 	cpuid = 0;
833 #endif
834 
835 	c = &cpu_data(cpuid);
836 	c->clock_tick = *cfreq;
837 
838 	tb = &trap_block[cpuid];
839 	get_mondo_data(hp, mp, tb);
840 
841 	mdesc_for_each_arc(a, hp, mp, MDESC_ARC_TYPE_FWD) {
842 		u64 j, t = mdesc_arc_target(hp, a);
843 		const char *t_name;
844 
845 		t_name = mdesc_node_name(hp, t);
846 		if (!strcmp(t_name, "cache")) {
847 			fill_in_one_cache(c, hp, t);
848 			continue;
849 		}
850 
851 		mdesc_for_each_arc(j, hp, t, MDESC_ARC_TYPE_FWD) {
852 			u64 n = mdesc_arc_target(hp, j);
853 			const char *n_name;
854 
855 			n_name = mdesc_node_name(hp, n);
856 			if (!strcmp(n_name, "cache"))
857 				fill_in_one_cache(c, hp, n);
858 		}
859 	}
860 
861 	c->core_id = 0;
862 	c->proc_id = -1;
863 
864 	return NULL;
865 }
866 
867 void __cpuinit mdesc_fill_in_cpu_data(cpumask_t *mask)
868 {
869 	struct mdesc_handle *hp;
870 
871 	mdesc_iterate_over_cpus(fill_in_one_cpu, NULL, mask);
872 
873 #ifdef CONFIG_SMP
874 	sparc64_multi_core = 1;
875 #endif
876 
877 	hp = mdesc_grab();
878 
879 	set_core_ids(hp);
880 	set_proc_ids(hp);
881 
882 	mdesc_release(hp);
883 
884 	smp_fill_in_sib_core_maps();
885 }
886 
887 static ssize_t mdesc_read(struct file *file, char __user *buf,
888 			  size_t len, loff_t *offp)
889 {
890 	struct mdesc_handle *hp = mdesc_grab();
891 	int err;
892 
893 	if (!hp)
894 		return -ENODEV;
895 
896 	err = hp->handle_size;
897 	if (len < hp->handle_size)
898 		err = -EMSGSIZE;
899 	else if (copy_to_user(buf, &hp->mdesc, hp->handle_size))
900 		err = -EFAULT;
901 	mdesc_release(hp);
902 
903 	return err;
904 }
905 
906 static const struct file_operations mdesc_fops = {
907 	.read	= mdesc_read,
908 	.owner	= THIS_MODULE,
909 	.llseek = noop_llseek,
910 };
911 
912 static struct miscdevice mdesc_misc = {
913 	.minor	= MISC_DYNAMIC_MINOR,
914 	.name	= "mdesc",
915 	.fops	= &mdesc_fops,
916 };
917 
918 static int __init mdesc_misc_init(void)
919 {
920 	return misc_register(&mdesc_misc);
921 }
922 
923 __initcall(mdesc_misc_init);
924 
925 void __init sun4v_mdesc_init(void)
926 {
927 	struct mdesc_handle *hp;
928 	unsigned long len, real_len, status;
929 
930 	(void) sun4v_mach_desc(0UL, 0UL, &len);
931 
932 	printk("MDESC: Size is %lu bytes.\n", len);
933 
934 	hp = mdesc_alloc(len, &memblock_mdesc_ops);
935 	if (hp == NULL) {
936 		prom_printf("MDESC: alloc of %lu bytes failed.\n", len);
937 		prom_halt();
938 	}
939 
940 	status = sun4v_mach_desc(__pa(&hp->mdesc), len, &real_len);
941 	if (status != HV_EOK || real_len > len) {
942 		prom_printf("sun4v_mach_desc fails, err(%lu), "
943 			    "len(%lu), real_len(%lu)\n",
944 			    status, len, real_len);
945 		mdesc_free(hp);
946 		prom_halt();
947 	}
948 
949 	cur_mdesc = hp;
950 
951 	report_platform_properties();
952 }
953