xref: /openbmc/linux/arch/powerpc/kernel/prom.c (revision f15cbe6f1a4b4d9df59142fc8e4abb973302cf44)
1 /*
2  * Procedures for creating, accessing and interpreting the device tree.
3  *
4  * Paul Mackerras	August 1996.
5  * Copyright (C) 1996-2005 Paul Mackerras.
6  *
7  *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
8  *    {engebret|bergner}@us.ibm.com
9  *
10  *      This program is free software; you can redistribute it and/or
11  *      modify it under the terms of the GNU General Public License
12  *      as published by the Free Software Foundation; either version
13  *      2 of the License, or (at your option) any later version.
14  */
15 
16 #undef DEBUG
17 
18 #include <stdarg.h>
19 #include <linux/kernel.h>
20 #include <linux/string.h>
21 #include <linux/init.h>
22 #include <linux/threads.h>
23 #include <linux/spinlock.h>
24 #include <linux/types.h>
25 #include <linux/pci.h>
26 #include <linux/stringify.h>
27 #include <linux/delay.h>
28 #include <linux/initrd.h>
29 #include <linux/bitops.h>
30 #include <linux/module.h>
31 #include <linux/kexec.h>
32 #include <linux/debugfs.h>
33 #include <linux/irq.h>
34 #include <linux/lmb.h>
35 
36 #include <asm/prom.h>
37 #include <asm/rtas.h>
38 #include <asm/page.h>
39 #include <asm/processor.h>
40 #include <asm/irq.h>
41 #include <asm/io.h>
42 #include <asm/kdump.h>
43 #include <asm/smp.h>
44 #include <asm/system.h>
45 #include <asm/mmu.h>
46 #include <asm/pgtable.h>
47 #include <asm/pci.h>
48 #include <asm/iommu.h>
49 #include <asm/btext.h>
50 #include <asm/sections.h>
51 #include <asm/machdep.h>
52 #include <asm/pSeries_reconfig.h>
53 #include <asm/pci-bridge.h>
54 #include <asm/phyp_dump.h>
55 #include <asm/kexec.h>
56 #include <mm/mmu_decl.h>
57 
58 #ifdef DEBUG
59 #define DBG(fmt...) printk(KERN_ERR fmt)
60 #else
61 #define DBG(fmt...)
62 #endif
63 
64 
65 static int __initdata dt_root_addr_cells;
66 static int __initdata dt_root_size_cells;
67 
68 #ifdef CONFIG_PPC64
69 int __initdata iommu_is_off;
70 int __initdata iommu_force_on;
71 unsigned long tce_alloc_start, tce_alloc_end;
72 #endif
73 
74 typedef u32 cell_t;
75 
76 #if 0
77 static struct boot_param_header *initial_boot_params __initdata;
78 #else
79 struct boot_param_header *initial_boot_params;
80 #endif
81 
82 extern struct device_node *allnodes;	/* temporary while merging */
83 
84 extern rwlock_t devtree_lock;	/* temporary while merging */
85 
86 /* export that to outside world */
87 struct device_node *of_chosen;
88 
89 static inline char *find_flat_dt_string(u32 offset)
90 {
91 	return ((char *)initial_boot_params) +
92 		initial_boot_params->off_dt_strings + offset;
93 }
94 
95 /**
96  * This function is used to scan the flattened device-tree, it is
97  * used to extract the memory informations at boot before we can
98  * unflatten the tree
99  */
100 int __init of_scan_flat_dt(int (*it)(unsigned long node,
101 				     const char *uname, int depth,
102 				     void *data),
103 			   void *data)
104 {
105 	unsigned long p = ((unsigned long)initial_boot_params) +
106 		initial_boot_params->off_dt_struct;
107 	int rc = 0;
108 	int depth = -1;
109 
110 	do {
111 		u32 tag = *((u32 *)p);
112 		char *pathp;
113 
114 		p += 4;
115 		if (tag == OF_DT_END_NODE) {
116 			depth --;
117 			continue;
118 		}
119 		if (tag == OF_DT_NOP)
120 			continue;
121 		if (tag == OF_DT_END)
122 			break;
123 		if (tag == OF_DT_PROP) {
124 			u32 sz = *((u32 *)p);
125 			p += 8;
126 			if (initial_boot_params->version < 0x10)
127 				p = _ALIGN(p, sz >= 8 ? 8 : 4);
128 			p += sz;
129 			p = _ALIGN(p, 4);
130 			continue;
131 		}
132 		if (tag != OF_DT_BEGIN_NODE) {
133 			printk(KERN_WARNING "Invalid tag %x scanning flattened"
134 			       " device tree !\n", tag);
135 			return -EINVAL;
136 		}
137 		depth++;
138 		pathp = (char *)p;
139 		p = _ALIGN(p + strlen(pathp) + 1, 4);
140 		if ((*pathp) == '/') {
141 			char *lp, *np;
142 			for (lp = NULL, np = pathp; *np; np++)
143 				if ((*np) == '/')
144 					lp = np+1;
145 			if (lp != NULL)
146 				pathp = lp;
147 		}
148 		rc = it(p, pathp, depth, data);
149 		if (rc != 0)
150 			break;
151 	} while(1);
152 
153 	return rc;
154 }
155 
156 unsigned long __init of_get_flat_dt_root(void)
157 {
158 	unsigned long p = ((unsigned long)initial_boot_params) +
159 		initial_boot_params->off_dt_struct;
160 
161 	while(*((u32 *)p) == OF_DT_NOP)
162 		p += 4;
163 	BUG_ON (*((u32 *)p) != OF_DT_BEGIN_NODE);
164 	p += 4;
165 	return _ALIGN(p + strlen((char *)p) + 1, 4);
166 }
167 
168 /**
169  * This  function can be used within scan_flattened_dt callback to get
170  * access to properties
171  */
172 void* __init of_get_flat_dt_prop(unsigned long node, const char *name,
173 				 unsigned long *size)
174 {
175 	unsigned long p = node;
176 
177 	do {
178 		u32 tag = *((u32 *)p);
179 		u32 sz, noff;
180 		const char *nstr;
181 
182 		p += 4;
183 		if (tag == OF_DT_NOP)
184 			continue;
185 		if (tag != OF_DT_PROP)
186 			return NULL;
187 
188 		sz = *((u32 *)p);
189 		noff = *((u32 *)(p + 4));
190 		p += 8;
191 		if (initial_boot_params->version < 0x10)
192 			p = _ALIGN(p, sz >= 8 ? 8 : 4);
193 
194 		nstr = find_flat_dt_string(noff);
195 		if (nstr == NULL) {
196 			printk(KERN_WARNING "Can't find property index"
197 			       " name !\n");
198 			return NULL;
199 		}
200 		if (strcmp(name, nstr) == 0) {
201 			if (size)
202 				*size = sz;
203 			return (void *)p;
204 		}
205 		p += sz;
206 		p = _ALIGN(p, 4);
207 	} while(1);
208 }
209 
210 int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
211 {
212 	const char* cp;
213 	unsigned long cplen, l;
214 
215 	cp = of_get_flat_dt_prop(node, "compatible", &cplen);
216 	if (cp == NULL)
217 		return 0;
218 	while (cplen > 0) {
219 		if (strncasecmp(cp, compat, strlen(compat)) == 0)
220 			return 1;
221 		l = strlen(cp) + 1;
222 		cp += l;
223 		cplen -= l;
224 	}
225 
226 	return 0;
227 }
228 
229 static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size,
230 				       unsigned long align)
231 {
232 	void *res;
233 
234 	*mem = _ALIGN(*mem, align);
235 	res = (void *)*mem;
236 	*mem += size;
237 
238 	return res;
239 }
240 
241 static unsigned long __init unflatten_dt_node(unsigned long mem,
242 					      unsigned long *p,
243 					      struct device_node *dad,
244 					      struct device_node ***allnextpp,
245 					      unsigned long fpsize)
246 {
247 	struct device_node *np;
248 	struct property *pp, **prev_pp = NULL;
249 	char *pathp;
250 	u32 tag;
251 	unsigned int l, allocl;
252 	int has_name = 0;
253 	int new_format = 0;
254 
255 	tag = *((u32 *)(*p));
256 	if (tag != OF_DT_BEGIN_NODE) {
257 		printk("Weird tag at start of node: %x\n", tag);
258 		return mem;
259 	}
260 	*p += 4;
261 	pathp = (char *)*p;
262 	l = allocl = strlen(pathp) + 1;
263 	*p = _ALIGN(*p + l, 4);
264 
265 	/* version 0x10 has a more compact unit name here instead of the full
266 	 * path. we accumulate the full path size using "fpsize", we'll rebuild
267 	 * it later. We detect this because the first character of the name is
268 	 * not '/'.
269 	 */
270 	if ((*pathp) != '/') {
271 		new_format = 1;
272 		if (fpsize == 0) {
273 			/* root node: special case. fpsize accounts for path
274 			 * plus terminating zero. root node only has '/', so
275 			 * fpsize should be 2, but we want to avoid the first
276 			 * level nodes to have two '/' so we use fpsize 1 here
277 			 */
278 			fpsize = 1;
279 			allocl = 2;
280 		} else {
281 			/* account for '/' and path size minus terminal 0
282 			 * already in 'l'
283 			 */
284 			fpsize += l;
285 			allocl = fpsize;
286 		}
287 	}
288 
289 
290 	np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
291 				__alignof__(struct device_node));
292 	if (allnextpp) {
293 		memset(np, 0, sizeof(*np));
294 		np->full_name = ((char*)np) + sizeof(struct device_node);
295 		if (new_format) {
296 			char *p = np->full_name;
297 			/* rebuild full path for new format */
298 			if (dad && dad->parent) {
299 				strcpy(p, dad->full_name);
300 #ifdef DEBUG
301 				if ((strlen(p) + l + 1) != allocl) {
302 					DBG("%s: p: %d, l: %d, a: %d\n",
303 					    pathp, (int)strlen(p), l, allocl);
304 				}
305 #endif
306 				p += strlen(p);
307 			}
308 			*(p++) = '/';
309 			memcpy(p, pathp, l);
310 		} else
311 			memcpy(np->full_name, pathp, l);
312 		prev_pp = &np->properties;
313 		**allnextpp = np;
314 		*allnextpp = &np->allnext;
315 		if (dad != NULL) {
316 			np->parent = dad;
317 			/* we temporarily use the next field as `last_child'*/
318 			if (dad->next == 0)
319 				dad->child = np;
320 			else
321 				dad->next->sibling = np;
322 			dad->next = np;
323 		}
324 		kref_init(&np->kref);
325 	}
326 	while(1) {
327 		u32 sz, noff;
328 		char *pname;
329 
330 		tag = *((u32 *)(*p));
331 		if (tag == OF_DT_NOP) {
332 			*p += 4;
333 			continue;
334 		}
335 		if (tag != OF_DT_PROP)
336 			break;
337 		*p += 4;
338 		sz = *((u32 *)(*p));
339 		noff = *((u32 *)((*p) + 4));
340 		*p += 8;
341 		if (initial_boot_params->version < 0x10)
342 			*p = _ALIGN(*p, sz >= 8 ? 8 : 4);
343 
344 		pname = find_flat_dt_string(noff);
345 		if (pname == NULL) {
346 			printk("Can't find property name in list !\n");
347 			break;
348 		}
349 		if (strcmp(pname, "name") == 0)
350 			has_name = 1;
351 		l = strlen(pname) + 1;
352 		pp = unflatten_dt_alloc(&mem, sizeof(struct property),
353 					__alignof__(struct property));
354 		if (allnextpp) {
355 			if (strcmp(pname, "linux,phandle") == 0) {
356 				np->node = *((u32 *)*p);
357 				if (np->linux_phandle == 0)
358 					np->linux_phandle = np->node;
359 			}
360 			if (strcmp(pname, "ibm,phandle") == 0)
361 				np->linux_phandle = *((u32 *)*p);
362 			pp->name = pname;
363 			pp->length = sz;
364 			pp->value = (void *)*p;
365 			*prev_pp = pp;
366 			prev_pp = &pp->next;
367 		}
368 		*p = _ALIGN((*p) + sz, 4);
369 	}
370 	/* with version 0x10 we may not have the name property, recreate
371 	 * it here from the unit name if absent
372 	 */
373 	if (!has_name) {
374 		char *p = pathp, *ps = pathp, *pa = NULL;
375 		int sz;
376 
377 		while (*p) {
378 			if ((*p) == '@')
379 				pa = p;
380 			if ((*p) == '/')
381 				ps = p + 1;
382 			p++;
383 		}
384 		if (pa < ps)
385 			pa = p;
386 		sz = (pa - ps) + 1;
387 		pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
388 					__alignof__(struct property));
389 		if (allnextpp) {
390 			pp->name = "name";
391 			pp->length = sz;
392 			pp->value = pp + 1;
393 			*prev_pp = pp;
394 			prev_pp = &pp->next;
395 			memcpy(pp->value, ps, sz - 1);
396 			((char *)pp->value)[sz - 1] = 0;
397 			DBG("fixed up name for %s -> %s\n", pathp,
398 				(char *)pp->value);
399 		}
400 	}
401 	if (allnextpp) {
402 		*prev_pp = NULL;
403 		np->name = of_get_property(np, "name", NULL);
404 		np->type = of_get_property(np, "device_type", NULL);
405 
406 		if (!np->name)
407 			np->name = "<NULL>";
408 		if (!np->type)
409 			np->type = "<NULL>";
410 	}
411 	while (tag == OF_DT_BEGIN_NODE) {
412 		mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize);
413 		tag = *((u32 *)(*p));
414 	}
415 	if (tag != OF_DT_END_NODE) {
416 		printk("Weird tag at end of node: %x\n", tag);
417 		return mem;
418 	}
419 	*p += 4;
420 	return mem;
421 }
422 
423 static int __init early_parse_mem(char *p)
424 {
425 	if (!p)
426 		return 1;
427 
428 	memory_limit = PAGE_ALIGN(memparse(p, &p));
429 	DBG("memory limit = 0x%lx\n", memory_limit);
430 
431 	return 0;
432 }
433 early_param("mem", early_parse_mem);
434 
435 /**
436  * move_device_tree - move tree to an unused area, if needed.
437  *
438  * The device tree may be allocated beyond our memory limit, or inside the
439  * crash kernel region for kdump. If so, move it out of the way.
440  */
441 static void __init move_device_tree(void)
442 {
443 	unsigned long start, size;
444 	void *p;
445 
446 	DBG("-> move_device_tree\n");
447 
448 	start = __pa(initial_boot_params);
449 	size = initial_boot_params->totalsize;
450 
451 	if ((memory_limit && (start + size) > memory_limit) ||
452 			overlaps_crashkernel(start, size)) {
453 		p = __va(lmb_alloc_base(size, PAGE_SIZE, lmb.rmo_size));
454 		memcpy(p, initial_boot_params, size);
455 		initial_boot_params = (struct boot_param_header *)p;
456 		DBG("Moved device tree to 0x%p\n", p);
457 	}
458 
459 	DBG("<- move_device_tree\n");
460 }
461 
462 /**
463  * unflattens the device-tree passed by the firmware, creating the
464  * tree of struct device_node. It also fills the "name" and "type"
465  * pointers of the nodes so the normal device-tree walking functions
466  * can be used (this used to be done by finish_device_tree)
467  */
468 void __init unflatten_device_tree(void)
469 {
470 	unsigned long start, mem, size;
471 	struct device_node **allnextp = &allnodes;
472 
473 	DBG(" -> unflatten_device_tree()\n");
474 
475 	/* First pass, scan for size */
476 	start = ((unsigned long)initial_boot_params) +
477 		initial_boot_params->off_dt_struct;
478 	size = unflatten_dt_node(0, &start, NULL, NULL, 0);
479 	size = (size | 3) + 1;
480 
481 	DBG("  size is %lx, allocating...\n", size);
482 
483 	/* Allocate memory for the expanded device tree */
484 	mem = lmb_alloc(size + 4, __alignof__(struct device_node));
485 	mem = (unsigned long) __va(mem);
486 
487 	((u32 *)mem)[size / 4] = 0xdeadbeef;
488 
489 	DBG("  unflattening %lx...\n", mem);
490 
491 	/* Second pass, do actual unflattening */
492 	start = ((unsigned long)initial_boot_params) +
493 		initial_boot_params->off_dt_struct;
494 	unflatten_dt_node(mem, &start, NULL, &allnextp, 0);
495 	if (*((u32 *)start) != OF_DT_END)
496 		printk(KERN_WARNING "Weird tag at end of tree: %08x\n", *((u32 *)start));
497 	if (((u32 *)mem)[size / 4] != 0xdeadbeef)
498 		printk(KERN_WARNING "End of tree marker overwritten: %08x\n",
499 		       ((u32 *)mem)[size / 4] );
500 	*allnextp = NULL;
501 
502 	/* Get pointer to OF "/chosen" node for use everywhere */
503 	of_chosen = of_find_node_by_path("/chosen");
504 	if (of_chosen == NULL)
505 		of_chosen = of_find_node_by_path("/chosen@0");
506 
507 	DBG(" <- unflatten_device_tree()\n");
508 }
509 
510 /*
511  * ibm,pa-features is a per-cpu property that contains a string of
512  * attribute descriptors, each of which has a 2 byte header plus up
513  * to 254 bytes worth of processor attribute bits.  First header
514  * byte specifies the number of bytes following the header.
515  * Second header byte is an "attribute-specifier" type, of which
516  * zero is the only currently-defined value.
517  * Implementation:  Pass in the byte and bit offset for the feature
518  * that we are interested in.  The function will return -1 if the
519  * pa-features property is missing, or a 1/0 to indicate if the feature
520  * is supported/not supported.  Note that the bit numbers are
521  * big-endian to match the definition in PAPR.
522  */
523 static struct ibm_pa_feature {
524 	unsigned long	cpu_features;	/* CPU_FTR_xxx bit */
525 	unsigned int	cpu_user_ftrs;	/* PPC_FEATURE_xxx bit */
526 	unsigned char	pabyte;		/* byte number in ibm,pa-features */
527 	unsigned char	pabit;		/* bit number (big-endian) */
528 	unsigned char	invert;		/* if 1, pa bit set => clear feature */
529 } ibm_pa_features[] __initdata = {
530 	{0, PPC_FEATURE_HAS_MMU,	0, 0, 0},
531 	{0, PPC_FEATURE_HAS_FPU,	0, 1, 0},
532 	{CPU_FTR_SLB, 0,		0, 2, 0},
533 	{CPU_FTR_CTRL, 0,		0, 3, 0},
534 	{CPU_FTR_NOEXECUTE, 0,		0, 6, 0},
535 	{CPU_FTR_NODSISRALIGN, 0,	1, 1, 1},
536 	{CPU_FTR_CI_LARGE_PAGE, 0,	1, 2, 0},
537 	{CPU_FTR_REAL_LE, PPC_FEATURE_TRUE_LE, 5, 0, 0},
538 };
539 
540 static void __init scan_features(unsigned long node, unsigned char *ftrs,
541 				 unsigned long tablelen,
542 				 struct ibm_pa_feature *fp,
543 				 unsigned long ft_size)
544 {
545 	unsigned long i, len, bit;
546 
547 	/* find descriptor with type == 0 */
548 	for (;;) {
549 		if (tablelen < 3)
550 			return;
551 		len = 2 + ftrs[0];
552 		if (tablelen < len)
553 			return;		/* descriptor 0 not found */
554 		if (ftrs[1] == 0)
555 			break;
556 		tablelen -= len;
557 		ftrs += len;
558 	}
559 
560 	/* loop over bits we know about */
561 	for (i = 0; i < ft_size; ++i, ++fp) {
562 		if (fp->pabyte >= ftrs[0])
563 			continue;
564 		bit = (ftrs[2 + fp->pabyte] >> (7 - fp->pabit)) & 1;
565 		if (bit ^ fp->invert) {
566 			cur_cpu_spec->cpu_features |= fp->cpu_features;
567 			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftrs;
568 		} else {
569 			cur_cpu_spec->cpu_features &= ~fp->cpu_features;
570 			cur_cpu_spec->cpu_user_features &= ~fp->cpu_user_ftrs;
571 		}
572 	}
573 }
574 
575 static void __init check_cpu_pa_features(unsigned long node)
576 {
577 	unsigned char *pa_ftrs;
578 	unsigned long tablelen;
579 
580 	pa_ftrs = of_get_flat_dt_prop(node, "ibm,pa-features", &tablelen);
581 	if (pa_ftrs == NULL)
582 		return;
583 
584 	scan_features(node, pa_ftrs, tablelen,
585 		      ibm_pa_features, ARRAY_SIZE(ibm_pa_features));
586 }
587 
588 #ifdef CONFIG_PPC64
589 static void __init check_cpu_slb_size(unsigned long node)
590 {
591 	u32 *slb_size_ptr;
592 
593 	slb_size_ptr = of_get_flat_dt_prop(node, "ibm,slb-size", NULL);
594 	if (slb_size_ptr != NULL) {
595 		mmu_slb_size = *slb_size_ptr;
596 	}
597 }
598 #else
599 #define check_cpu_slb_size(node) do { } while(0)
600 #endif
601 
602 static struct feature_property {
603 	const char *name;
604 	u32 min_value;
605 	unsigned long cpu_feature;
606 	unsigned long cpu_user_ftr;
607 } feature_properties[] __initdata = {
608 #ifdef CONFIG_ALTIVEC
609 	{"altivec", 0, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
610 	{"ibm,vmx", 1, CPU_FTR_ALTIVEC, PPC_FEATURE_HAS_ALTIVEC},
611 #endif /* CONFIG_ALTIVEC */
612 #ifdef CONFIG_VSX
613 	/* Yes, this _really_ is ibm,vmx == 2 to enable VSX */
614 	{"ibm,vmx", 2, CPU_FTR_VSX, PPC_FEATURE_HAS_VSX},
615 #endif /* CONFIG_VSX */
616 #ifdef CONFIG_PPC64
617 	{"ibm,dfp", 1, 0, PPC_FEATURE_HAS_DFP},
618 	{"ibm,purr", 1, CPU_FTR_PURR, 0},
619 	{"ibm,spurr", 1, CPU_FTR_SPURR, 0},
620 #endif /* CONFIG_PPC64 */
621 };
622 
623 #if defined(CONFIG_44x) && defined(CONFIG_PPC_FPU)
624 static inline void identical_pvr_fixup(unsigned long node)
625 {
626 	unsigned int pvr;
627 	char *model = of_get_flat_dt_prop(node, "model", NULL);
628 
629 	/*
630 	 * Since 440GR(x)/440EP(x) processors have the same pvr,
631 	 * we check the node path and set bit 28 in the cur_cpu_spec
632 	 * pvr for EP(x) processor version. This bit is always 0 in
633 	 * the "real" pvr. Then we call identify_cpu again with
634 	 * the new logical pvr to enable FPU support.
635 	 */
636 	if (model && strstr(model, "440EP")) {
637 		pvr = cur_cpu_spec->pvr_value | 0x8;
638 		identify_cpu(0, pvr);
639 		DBG("Using logical pvr %x for %s\n", pvr, model);
640 	}
641 }
642 #else
643 #define identical_pvr_fixup(node) do { } while(0)
644 #endif
645 
646 static void __init check_cpu_feature_properties(unsigned long node)
647 {
648 	unsigned long i;
649 	struct feature_property *fp = feature_properties;
650 	const u32 *prop;
651 
652 	for (i = 0; i < ARRAY_SIZE(feature_properties); ++i, ++fp) {
653 		prop = of_get_flat_dt_prop(node, fp->name, NULL);
654 		if (prop && *prop >= fp->min_value) {
655 			cur_cpu_spec->cpu_features |= fp->cpu_feature;
656 			cur_cpu_spec->cpu_user_features |= fp->cpu_user_ftr;
657 		}
658 	}
659 }
660 
661 static int __init early_init_dt_scan_cpus(unsigned long node,
662 					  const char *uname, int depth,
663 					  void *data)
664 {
665 	static int logical_cpuid = 0;
666 	char *type = of_get_flat_dt_prop(node, "device_type", NULL);
667 	const u32 *prop;
668 	const u32 *intserv;
669 	int i, nthreads;
670 	unsigned long len;
671 	int found = 0;
672 
673 	/* We are scanning "cpu" nodes only */
674 	if (type == NULL || strcmp(type, "cpu") != 0)
675 		return 0;
676 
677 	/* Get physical cpuid */
678 	intserv = of_get_flat_dt_prop(node, "ibm,ppc-interrupt-server#s", &len);
679 	if (intserv) {
680 		nthreads = len / sizeof(int);
681 	} else {
682 		intserv = of_get_flat_dt_prop(node, "reg", NULL);
683 		nthreads = 1;
684 	}
685 
686 	/*
687 	 * Now see if any of these threads match our boot cpu.
688 	 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
689 	 */
690 	for (i = 0; i < nthreads; i++) {
691 		/*
692 		 * version 2 of the kexec param format adds the phys cpuid of
693 		 * booted proc.
694 		 */
695 		if (initial_boot_params && initial_boot_params->version >= 2) {
696 			if (intserv[i] ==
697 					initial_boot_params->boot_cpuid_phys) {
698 				found = 1;
699 				break;
700 			}
701 		} else {
702 			/*
703 			 * Check if it's the boot-cpu, set it's hw index now,
704 			 * unfortunately this format did not support booting
705 			 * off secondary threads.
706 			 */
707 			if (of_get_flat_dt_prop(node,
708 					"linux,boot-cpu", NULL) != NULL) {
709 				found = 1;
710 				break;
711 			}
712 		}
713 
714 #ifdef CONFIG_SMP
715 		/* logical cpu id is always 0 on UP kernels */
716 		logical_cpuid++;
717 #endif
718 	}
719 
720 	if (found) {
721 		DBG("boot cpu: logical %d physical %d\n", logical_cpuid,
722 			intserv[i]);
723 		boot_cpuid = logical_cpuid;
724 		set_hard_smp_processor_id(boot_cpuid, intserv[i]);
725 
726 		/*
727 		 * PAPR defines "logical" PVR values for cpus that
728 		 * meet various levels of the architecture:
729 		 * 0x0f000001	Architecture version 2.04
730 		 * 0x0f000002	Architecture version 2.05
731 		 * If the cpu-version property in the cpu node contains
732 		 * such a value, we call identify_cpu again with the
733 		 * logical PVR value in order to use the cpu feature
734 		 * bits appropriate for the architecture level.
735 		 *
736 		 * A POWER6 partition in "POWER6 architected" mode
737 		 * uses the 0x0f000002 PVR value; in POWER5+ mode
738 		 * it uses 0x0f000001.
739 		 */
740 		prop = of_get_flat_dt_prop(node, "cpu-version", NULL);
741 		if (prop && (*prop & 0xff000000) == 0x0f000000)
742 			identify_cpu(0, *prop);
743 
744 		identical_pvr_fixup(node);
745 	}
746 
747 	check_cpu_feature_properties(node);
748 	check_cpu_pa_features(node);
749 	check_cpu_slb_size(node);
750 
751 #ifdef CONFIG_PPC_PSERIES
752 	if (nthreads > 1)
753 		cur_cpu_spec->cpu_features |= CPU_FTR_SMT;
754 	else
755 		cur_cpu_spec->cpu_features &= ~CPU_FTR_SMT;
756 #endif
757 
758 	return 0;
759 }
760 
761 #ifdef CONFIG_BLK_DEV_INITRD
762 static void __init early_init_dt_check_for_initrd(unsigned long node)
763 {
764 	unsigned long l;
765 	u32 *prop;
766 
767 	DBG("Looking for initrd properties... ");
768 
769 	prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l);
770 	if (prop) {
771 		initrd_start = (unsigned long)__va(of_read_ulong(prop, l/4));
772 
773 		prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
774 		if (prop) {
775 			initrd_end = (unsigned long)
776 					__va(of_read_ulong(prop, l/4));
777 			initrd_below_start_ok = 1;
778 		} else {
779 			initrd_start = 0;
780 		}
781 	}
782 
783 	DBG("initrd_start=0x%lx  initrd_end=0x%lx\n", initrd_start, initrd_end);
784 }
785 #else
786 static inline void early_init_dt_check_for_initrd(unsigned long node)
787 {
788 }
789 #endif /* CONFIG_BLK_DEV_INITRD */
790 
791 static int __init early_init_dt_scan_chosen(unsigned long node,
792 					    const char *uname, int depth, void *data)
793 {
794 	unsigned long *lprop;
795 	unsigned long l;
796 	char *p;
797 
798 	DBG("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
799 
800 	if (depth != 1 ||
801 	    (strcmp(uname, "chosen") != 0 && strcmp(uname, "chosen@0") != 0))
802 		return 0;
803 
804 #ifdef CONFIG_PPC64
805 	/* check if iommu is forced on or off */
806 	if (of_get_flat_dt_prop(node, "linux,iommu-off", NULL) != NULL)
807 		iommu_is_off = 1;
808 	if (of_get_flat_dt_prop(node, "linux,iommu-force-on", NULL) != NULL)
809 		iommu_force_on = 1;
810 #endif
811 
812 	/* mem=x on the command line is the preferred mechanism */
813  	lprop = of_get_flat_dt_prop(node, "linux,memory-limit", NULL);
814  	if (lprop)
815  		memory_limit = *lprop;
816 
817 #ifdef CONFIG_PPC64
818  	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-start", NULL);
819  	if (lprop)
820  		tce_alloc_start = *lprop;
821  	lprop = of_get_flat_dt_prop(node, "linux,tce-alloc-end", NULL);
822  	if (lprop)
823  		tce_alloc_end = *lprop;
824 #endif
825 
826 #ifdef CONFIG_KEXEC
827 	lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-base", NULL);
828 	if (lprop)
829 		crashk_res.start = *lprop;
830 
831 	lprop = (u64*)of_get_flat_dt_prop(node, "linux,crashkernel-size", NULL);
832 	if (lprop)
833 		crashk_res.end = crashk_res.start + *lprop - 1;
834 #endif
835 
836 	early_init_dt_check_for_initrd(node);
837 
838 	/* Retreive command line */
839  	p = of_get_flat_dt_prop(node, "bootargs", &l);
840 	if (p != NULL && l > 0)
841 		strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
842 
843 #ifdef CONFIG_CMDLINE
844 	if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
845 		strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
846 #endif /* CONFIG_CMDLINE */
847 
848 	DBG("Command line is: %s\n", cmd_line);
849 
850 	/* break now */
851 	return 1;
852 }
853 
854 static int __init early_init_dt_scan_root(unsigned long node,
855 					  const char *uname, int depth, void *data)
856 {
857 	u32 *prop;
858 
859 	if (depth != 0)
860 		return 0;
861 
862 	prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
863 	dt_root_size_cells = (prop == NULL) ? 1 : *prop;
864 	DBG("dt_root_size_cells = %x\n", dt_root_size_cells);
865 
866 	prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
867 	dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
868 	DBG("dt_root_addr_cells = %x\n", dt_root_addr_cells);
869 
870 	/* break now */
871 	return 1;
872 }
873 
874 static u64 __init dt_mem_next_cell(int s, cell_t **cellp)
875 {
876 	cell_t *p = *cellp;
877 
878 	*cellp = p + s;
879 	return of_read_number(p, s);
880 }
881 
882 #ifdef CONFIG_PPC_PSERIES
883 /*
884  * Interpret the ibm,dynamic-memory property in the
885  * /ibm,dynamic-reconfiguration-memory node.
886  * This contains a list of memory blocks along with NUMA affinity
887  * information.
888  */
889 static int __init early_init_dt_scan_drconf_memory(unsigned long node)
890 {
891 	cell_t *dm, *ls;
892 	unsigned long l, n, flags;
893 	u64 base, size, lmb_size;
894 
895 	ls = (cell_t *)of_get_flat_dt_prop(node, "ibm,lmb-size", &l);
896 	if (ls == NULL || l < dt_root_size_cells * sizeof(cell_t))
897 		return 0;
898 	lmb_size = dt_mem_next_cell(dt_root_size_cells, &ls);
899 
900 	dm = (cell_t *)of_get_flat_dt_prop(node, "ibm,dynamic-memory", &l);
901 	if (dm == NULL || l < sizeof(cell_t))
902 		return 0;
903 
904 	n = *dm++;	/* number of entries */
905 	if (l < (n * (dt_root_addr_cells + 4) + 1) * sizeof(cell_t))
906 		return 0;
907 
908 	for (; n != 0; --n) {
909 		base = dt_mem_next_cell(dt_root_addr_cells, &dm);
910 		flags = dm[3];
911 		/* skip DRC index, pad, assoc. list index, flags */
912 		dm += 4;
913 		/* skip this block if the reserved bit is set in flags (0x80)
914 		   or if the block is not assigned to this partition (0x8) */
915 		if ((flags & 0x80) || !(flags & 0x8))
916 			continue;
917 		size = lmb_size;
918 		if (iommu_is_off) {
919 			if (base >= 0x80000000ul)
920 				continue;
921 			if ((base + size) > 0x80000000ul)
922 				size = 0x80000000ul - base;
923 		}
924 		lmb_add(base, size);
925 	}
926 	lmb_dump_all();
927 	return 0;
928 }
929 #else
930 #define early_init_dt_scan_drconf_memory(node)	0
931 #endif /* CONFIG_PPC_PSERIES */
932 
933 static int __init early_init_dt_scan_memory(unsigned long node,
934 					    const char *uname, int depth, void *data)
935 {
936 	char *type = of_get_flat_dt_prop(node, "device_type", NULL);
937 	cell_t *reg, *endp;
938 	unsigned long l;
939 
940 	/* Look for the ibm,dynamic-reconfiguration-memory node */
941 	if (depth == 1 &&
942 	    strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
943 		return early_init_dt_scan_drconf_memory(node);
944 
945 	/* We are scanning "memory" nodes only */
946 	if (type == NULL) {
947 		/*
948 		 * The longtrail doesn't have a device_type on the
949 		 * /memory node, so look for the node called /memory@0.
950 		 */
951 		if (depth != 1 || strcmp(uname, "memory@0") != 0)
952 			return 0;
953 	} else if (strcmp(type, "memory") != 0)
954 		return 0;
955 
956 	reg = (cell_t *)of_get_flat_dt_prop(node, "linux,usable-memory", &l);
957 	if (reg == NULL)
958 		reg = (cell_t *)of_get_flat_dt_prop(node, "reg", &l);
959 	if (reg == NULL)
960 		return 0;
961 
962 	endp = reg + (l / sizeof(cell_t));
963 
964 	DBG("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
965 	    uname, l, reg[0], reg[1], reg[2], reg[3]);
966 
967 	while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
968 		u64 base, size;
969 
970 		base = dt_mem_next_cell(dt_root_addr_cells, &reg);
971 		size = dt_mem_next_cell(dt_root_size_cells, &reg);
972 
973 		if (size == 0)
974 			continue;
975 		DBG(" - %llx ,  %llx\n", (unsigned long long)base,
976 		    (unsigned long long)size);
977 #ifdef CONFIG_PPC64
978 		if (iommu_is_off) {
979 			if (base >= 0x80000000ul)
980 				continue;
981 			if ((base + size) > 0x80000000ul)
982 				size = 0x80000000ul - base;
983 		}
984 #endif
985 		lmb_add(base, size);
986 
987 		memstart_addr = min((u64)memstart_addr, base);
988 	}
989 
990 	return 0;
991 }
992 
993 static void __init early_reserve_mem(void)
994 {
995 	u64 base, size;
996 	u64 *reserve_map;
997 	unsigned long self_base;
998 	unsigned long self_size;
999 
1000 	reserve_map = (u64 *)(((unsigned long)initial_boot_params) +
1001 					initial_boot_params->off_mem_rsvmap);
1002 
1003 	/* before we do anything, lets reserve the dt blob */
1004 	self_base = __pa((unsigned long)initial_boot_params);
1005 	self_size = initial_boot_params->totalsize;
1006 	lmb_reserve(self_base, self_size);
1007 
1008 #ifdef CONFIG_BLK_DEV_INITRD
1009 	/* then reserve the initrd, if any */
1010 	if (initrd_start && (initrd_end > initrd_start))
1011 		lmb_reserve(__pa(initrd_start), initrd_end - initrd_start);
1012 #endif /* CONFIG_BLK_DEV_INITRD */
1013 
1014 #ifdef CONFIG_PPC32
1015 	/*
1016 	 * Handle the case where we might be booting from an old kexec
1017 	 * image that setup the mem_rsvmap as pairs of 32-bit values
1018 	 */
1019 	if (*reserve_map > 0xffffffffull) {
1020 		u32 base_32, size_32;
1021 		u32 *reserve_map_32 = (u32 *)reserve_map;
1022 
1023 		while (1) {
1024 			base_32 = *(reserve_map_32++);
1025 			size_32 = *(reserve_map_32++);
1026 			if (size_32 == 0)
1027 				break;
1028 			/* skip if the reservation is for the blob */
1029 			if (base_32 == self_base && size_32 == self_size)
1030 				continue;
1031 			DBG("reserving: %x -> %x\n", base_32, size_32);
1032 			lmb_reserve(base_32, size_32);
1033 		}
1034 		return;
1035 	}
1036 #endif
1037 	while (1) {
1038 		base = *(reserve_map++);
1039 		size = *(reserve_map++);
1040 		if (size == 0)
1041 			break;
1042 		DBG("reserving: %llx -> %llx\n", base, size);
1043 		lmb_reserve(base, size);
1044 	}
1045 
1046 #if 0
1047 	DBG("memory reserved, lmbs :\n");
1048       	lmb_dump_all();
1049 #endif
1050 }
1051 
1052 #ifdef CONFIG_PHYP_DUMP
1053 /**
1054  * phyp_dump_calculate_reserve_size() - reserve variable boot area 5% or arg
1055  *
1056  * Function to find the largest size we need to reserve
1057  * during early boot process.
1058  *
1059  * It either looks for boot param and returns that OR
1060  * returns larger of 256 or 5% rounded down to multiples of 256MB.
1061  *
1062  */
1063 static inline unsigned long phyp_dump_calculate_reserve_size(void)
1064 {
1065 	unsigned long tmp;
1066 
1067 	if (phyp_dump_info->reserve_bootvar)
1068 		return phyp_dump_info->reserve_bootvar;
1069 
1070 	/* divide by 20 to get 5% of value */
1071 	tmp = lmb_end_of_DRAM();
1072 	do_div(tmp, 20);
1073 
1074 	/* round it down in multiples of 256 */
1075 	tmp = tmp & ~0x0FFFFFFFUL;
1076 
1077 	return (tmp > PHYP_DUMP_RMR_END ? tmp : PHYP_DUMP_RMR_END);
1078 }
1079 
1080 /**
1081  * phyp_dump_reserve_mem() - reserve all not-yet-dumped mmemory
1082  *
1083  * This routine may reserve memory regions in the kernel only
1084  * if the system is supported and a dump was taken in last
1085  * boot instance or if the hardware is supported and the
1086  * scratch area needs to be setup. In other instances it returns
1087  * without reserving anything. The memory in case of dump being
1088  * active is freed when the dump is collected (by userland tools).
1089  */
1090 static void __init phyp_dump_reserve_mem(void)
1091 {
1092 	unsigned long base, size;
1093 	unsigned long variable_reserve_size;
1094 
1095 	if (!phyp_dump_info->phyp_dump_configured) {
1096 		printk(KERN_ERR "Phyp-dump not supported on this hardware\n");
1097 		return;
1098 	}
1099 
1100 	if (!phyp_dump_info->phyp_dump_at_boot) {
1101 		printk(KERN_INFO "Phyp-dump disabled at boot time\n");
1102 		return;
1103 	}
1104 
1105 	variable_reserve_size = phyp_dump_calculate_reserve_size();
1106 
1107 	if (phyp_dump_info->phyp_dump_is_active) {
1108 		/* Reserve *everything* above RMR.Area freed by userland tools*/
1109 		base = variable_reserve_size;
1110 		size = lmb_end_of_DRAM() - base;
1111 
1112 		/* XXX crashed_ram_end is wrong, since it may be beyond
1113 		 * the memory_limit, it will need to be adjusted. */
1114 		lmb_reserve(base, size);
1115 
1116 		phyp_dump_info->init_reserve_start = base;
1117 		phyp_dump_info->init_reserve_size = size;
1118 	} else {
1119 		size = phyp_dump_info->cpu_state_size +
1120 			phyp_dump_info->hpte_region_size +
1121 			variable_reserve_size;
1122 		base = lmb_end_of_DRAM() - size;
1123 		lmb_reserve(base, size);
1124 		phyp_dump_info->init_reserve_start = base;
1125 		phyp_dump_info->init_reserve_size = size;
1126 	}
1127 }
1128 #else
1129 static inline void __init phyp_dump_reserve_mem(void) {}
1130 #endif /* CONFIG_PHYP_DUMP  && CONFIG_PPC_RTAS */
1131 
1132 
1133 void __init early_init_devtree(void *params)
1134 {
1135 	DBG(" -> early_init_devtree(%p)\n", params);
1136 
1137 	/* Setup flat device-tree pointer */
1138 	initial_boot_params = params;
1139 
1140 #ifdef CONFIG_PPC_RTAS
1141 	/* Some machines might need RTAS info for debugging, grab it now. */
1142 	of_scan_flat_dt(early_init_dt_scan_rtas, NULL);
1143 #endif
1144 
1145 #ifdef CONFIG_PHYP_DUMP
1146 	/* scan tree to see if dump occured during last boot */
1147 	of_scan_flat_dt(early_init_dt_scan_phyp_dump, NULL);
1148 #endif
1149 
1150 	/* Retrieve various informations from the /chosen node of the
1151 	 * device-tree, including the platform type, initrd location and
1152 	 * size, TCE reserve, and more ...
1153 	 */
1154 	of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
1155 
1156 	/* Scan memory nodes and rebuild LMBs */
1157 	lmb_init();
1158 	of_scan_flat_dt(early_init_dt_scan_root, NULL);
1159 	of_scan_flat_dt(early_init_dt_scan_memory, NULL);
1160 
1161 	/* Save command line for /proc/cmdline and then parse parameters */
1162 	strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
1163 	parse_early_param();
1164 
1165 	/* Reserve LMB regions used by kernel, initrd, dt, etc... */
1166 	lmb_reserve(PHYSICAL_START, __pa(klimit) - PHYSICAL_START);
1167 	reserve_kdump_trampoline();
1168 	reserve_crashkernel();
1169 	early_reserve_mem();
1170 	phyp_dump_reserve_mem();
1171 
1172 	lmb_enforce_memory_limit(memory_limit);
1173 	lmb_analyze();
1174 
1175 	DBG("Phys. mem: %lx\n", lmb_phys_mem_size());
1176 
1177 	/* We may need to relocate the flat tree, do it now.
1178 	 * FIXME .. and the initrd too? */
1179 	move_device_tree();
1180 
1181 	DBG("Scanning CPUs ...\n");
1182 
1183 	/* Retreive CPU related informations from the flat tree
1184 	 * (altivec support, boot CPU ID, ...)
1185 	 */
1186 	of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
1187 
1188 	DBG(" <- early_init_devtree()\n");
1189 }
1190 
1191 
1192 /**
1193  * Indicates whether the root node has a given value in its
1194  * compatible property.
1195  */
1196 int machine_is_compatible(const char *compat)
1197 {
1198 	struct device_node *root;
1199 	int rc = 0;
1200 
1201 	root = of_find_node_by_path("/");
1202 	if (root) {
1203 		rc = of_device_is_compatible(root, compat);
1204 		of_node_put(root);
1205 	}
1206 	return rc;
1207 }
1208 EXPORT_SYMBOL(machine_is_compatible);
1209 
1210 /*******
1211  *
1212  * New implementation of the OF "find" APIs, return a refcounted
1213  * object, call of_node_put() when done.  The device tree and list
1214  * are protected by a rw_lock.
1215  *
1216  * Note that property management will need some locking as well,
1217  * this isn't dealt with yet.
1218  *
1219  *******/
1220 
1221 /**
1222  *	of_find_node_by_phandle - Find a node given a phandle
1223  *	@handle:	phandle of the node to find
1224  *
1225  *	Returns a node pointer with refcount incremented, use
1226  *	of_node_put() on it when done.
1227  */
1228 struct device_node *of_find_node_by_phandle(phandle handle)
1229 {
1230 	struct device_node *np;
1231 
1232 	read_lock(&devtree_lock);
1233 	for (np = allnodes; np != 0; np = np->allnext)
1234 		if (np->linux_phandle == handle)
1235 			break;
1236 	of_node_get(np);
1237 	read_unlock(&devtree_lock);
1238 	return np;
1239 }
1240 EXPORT_SYMBOL(of_find_node_by_phandle);
1241 
1242 /**
1243  *	of_find_all_nodes - Get next node in global list
1244  *	@prev:	Previous node or NULL to start iteration
1245  *		of_node_put() will be called on it
1246  *
1247  *	Returns a node pointer with refcount incremented, use
1248  *	of_node_put() on it when done.
1249  */
1250 struct device_node *of_find_all_nodes(struct device_node *prev)
1251 {
1252 	struct device_node *np;
1253 
1254 	read_lock(&devtree_lock);
1255 	np = prev ? prev->allnext : allnodes;
1256 	for (; np != 0; np = np->allnext)
1257 		if (of_node_get(np))
1258 			break;
1259 	of_node_put(prev);
1260 	read_unlock(&devtree_lock);
1261 	return np;
1262 }
1263 EXPORT_SYMBOL(of_find_all_nodes);
1264 
1265 /**
1266  *	of_node_get - Increment refcount of a node
1267  *	@node:	Node to inc refcount, NULL is supported to
1268  *		simplify writing of callers
1269  *
1270  *	Returns node.
1271  */
1272 struct device_node *of_node_get(struct device_node *node)
1273 {
1274 	if (node)
1275 		kref_get(&node->kref);
1276 	return node;
1277 }
1278 EXPORT_SYMBOL(of_node_get);
1279 
1280 static inline struct device_node * kref_to_device_node(struct kref *kref)
1281 {
1282 	return container_of(kref, struct device_node, kref);
1283 }
1284 
1285 /**
1286  *	of_node_release - release a dynamically allocated node
1287  *	@kref:  kref element of the node to be released
1288  *
1289  *	In of_node_put() this function is passed to kref_put()
1290  *	as the destructor.
1291  */
1292 static void of_node_release(struct kref *kref)
1293 {
1294 	struct device_node *node = kref_to_device_node(kref);
1295 	struct property *prop = node->properties;
1296 
1297 	/* We should never be releasing nodes that haven't been detached. */
1298 	if (!of_node_check_flag(node, OF_DETACHED)) {
1299 		printk("WARNING: Bad of_node_put() on %s\n", node->full_name);
1300 		dump_stack();
1301 		kref_init(&node->kref);
1302 		return;
1303 	}
1304 
1305 	if (!of_node_check_flag(node, OF_DYNAMIC))
1306 		return;
1307 
1308 	while (prop) {
1309 		struct property *next = prop->next;
1310 		kfree(prop->name);
1311 		kfree(prop->value);
1312 		kfree(prop);
1313 		prop = next;
1314 
1315 		if (!prop) {
1316 			prop = node->deadprops;
1317 			node->deadprops = NULL;
1318 		}
1319 	}
1320 	kfree(node->full_name);
1321 	kfree(node->data);
1322 	kfree(node);
1323 }
1324 
1325 /**
1326  *	of_node_put - Decrement refcount of a node
1327  *	@node:	Node to dec refcount, NULL is supported to
1328  *		simplify writing of callers
1329  *
1330  */
1331 void of_node_put(struct device_node *node)
1332 {
1333 	if (node)
1334 		kref_put(&node->kref, of_node_release);
1335 }
1336 EXPORT_SYMBOL(of_node_put);
1337 
1338 /*
1339  * Plug a device node into the tree and global list.
1340  */
1341 void of_attach_node(struct device_node *np)
1342 {
1343 	unsigned long flags;
1344 
1345 	write_lock_irqsave(&devtree_lock, flags);
1346 	np->sibling = np->parent->child;
1347 	np->allnext = allnodes;
1348 	np->parent->child = np;
1349 	allnodes = np;
1350 	write_unlock_irqrestore(&devtree_lock, flags);
1351 }
1352 
1353 /*
1354  * "Unplug" a node from the device tree.  The caller must hold
1355  * a reference to the node.  The memory associated with the node
1356  * is not freed until its refcount goes to zero.
1357  */
1358 void of_detach_node(struct device_node *np)
1359 {
1360 	struct device_node *parent;
1361 	unsigned long flags;
1362 
1363 	write_lock_irqsave(&devtree_lock, flags);
1364 
1365 	parent = np->parent;
1366 	if (!parent)
1367 		goto out_unlock;
1368 
1369 	if (allnodes == np)
1370 		allnodes = np->allnext;
1371 	else {
1372 		struct device_node *prev;
1373 		for (prev = allnodes;
1374 		     prev->allnext != np;
1375 		     prev = prev->allnext)
1376 			;
1377 		prev->allnext = np->allnext;
1378 	}
1379 
1380 	if (parent->child == np)
1381 		parent->child = np->sibling;
1382 	else {
1383 		struct device_node *prevsib;
1384 		for (prevsib = np->parent->child;
1385 		     prevsib->sibling != np;
1386 		     prevsib = prevsib->sibling)
1387 			;
1388 		prevsib->sibling = np->sibling;
1389 	}
1390 
1391 	of_node_set_flag(np, OF_DETACHED);
1392 
1393 out_unlock:
1394 	write_unlock_irqrestore(&devtree_lock, flags);
1395 }
1396 
1397 #ifdef CONFIG_PPC_PSERIES
1398 /*
1399  * Fix up the uninitialized fields in a new device node:
1400  * name, type and pci-specific fields
1401  */
1402 
1403 static int of_finish_dynamic_node(struct device_node *node)
1404 {
1405 	struct device_node *parent = of_get_parent(node);
1406 	int err = 0;
1407 	const phandle *ibm_phandle;
1408 
1409 	node->name = of_get_property(node, "name", NULL);
1410 	node->type = of_get_property(node, "device_type", NULL);
1411 
1412 	if (!node->name)
1413 		node->name = "<NULL>";
1414 	if (!node->type)
1415 		node->type = "<NULL>";
1416 
1417 	if (!parent) {
1418 		err = -ENODEV;
1419 		goto out;
1420 	}
1421 
1422 	/* We don't support that function on PowerMac, at least
1423 	 * not yet
1424 	 */
1425 	if (machine_is(powermac))
1426 		return -ENODEV;
1427 
1428 	/* fix up new node's linux_phandle field */
1429 	if ((ibm_phandle = of_get_property(node, "ibm,phandle", NULL)))
1430 		node->linux_phandle = *ibm_phandle;
1431 
1432 out:
1433 	of_node_put(parent);
1434 	return err;
1435 }
1436 
1437 static int prom_reconfig_notifier(struct notifier_block *nb,
1438 				  unsigned long action, void *node)
1439 {
1440 	int err;
1441 
1442 	switch (action) {
1443 	case PSERIES_RECONFIG_ADD:
1444 		err = of_finish_dynamic_node(node);
1445 		if (err < 0) {
1446 			printk(KERN_ERR "finish_node returned %d\n", err);
1447 			err = NOTIFY_BAD;
1448 		}
1449 		break;
1450 	default:
1451 		err = NOTIFY_DONE;
1452 		break;
1453 	}
1454 	return err;
1455 }
1456 
1457 static struct notifier_block prom_reconfig_nb = {
1458 	.notifier_call = prom_reconfig_notifier,
1459 	.priority = 10, /* This one needs to run first */
1460 };
1461 
1462 static int __init prom_reconfig_setup(void)
1463 {
1464 	return pSeries_reconfig_notifier_register(&prom_reconfig_nb);
1465 }
1466 __initcall(prom_reconfig_setup);
1467 #endif
1468 
1469 /*
1470  * Add a property to a node
1471  */
1472 int prom_add_property(struct device_node* np, struct property* prop)
1473 {
1474 	struct property **next;
1475 	unsigned long flags;
1476 
1477 	prop->next = NULL;
1478 	write_lock_irqsave(&devtree_lock, flags);
1479 	next = &np->properties;
1480 	while (*next) {
1481 		if (strcmp(prop->name, (*next)->name) == 0) {
1482 			/* duplicate ! don't insert it */
1483 			write_unlock_irqrestore(&devtree_lock, flags);
1484 			return -1;
1485 		}
1486 		next = &(*next)->next;
1487 	}
1488 	*next = prop;
1489 	write_unlock_irqrestore(&devtree_lock, flags);
1490 
1491 #ifdef CONFIG_PROC_DEVICETREE
1492 	/* try to add to proc as well if it was initialized */
1493 	if (np->pde)
1494 		proc_device_tree_add_prop(np->pde, prop);
1495 #endif /* CONFIG_PROC_DEVICETREE */
1496 
1497 	return 0;
1498 }
1499 
1500 /*
1501  * Remove a property from a node.  Note that we don't actually
1502  * remove it, since we have given out who-knows-how-many pointers
1503  * to the data using get-property.  Instead we just move the property
1504  * to the "dead properties" list, so it won't be found any more.
1505  */
1506 int prom_remove_property(struct device_node *np, struct property *prop)
1507 {
1508 	struct property **next;
1509 	unsigned long flags;
1510 	int found = 0;
1511 
1512 	write_lock_irqsave(&devtree_lock, flags);
1513 	next = &np->properties;
1514 	while (*next) {
1515 		if (*next == prop) {
1516 			/* found the node */
1517 			*next = prop->next;
1518 			prop->next = np->deadprops;
1519 			np->deadprops = prop;
1520 			found = 1;
1521 			break;
1522 		}
1523 		next = &(*next)->next;
1524 	}
1525 	write_unlock_irqrestore(&devtree_lock, flags);
1526 
1527 	if (!found)
1528 		return -ENODEV;
1529 
1530 #ifdef CONFIG_PROC_DEVICETREE
1531 	/* try to remove the proc node as well */
1532 	if (np->pde)
1533 		proc_device_tree_remove_prop(np->pde, prop);
1534 #endif /* CONFIG_PROC_DEVICETREE */
1535 
1536 	return 0;
1537 }
1538 
1539 /*
1540  * Update a property in a node.  Note that we don't actually
1541  * remove it, since we have given out who-knows-how-many pointers
1542  * to the data using get-property.  Instead we just move the property
1543  * to the "dead properties" list, and add the new property to the
1544  * property list
1545  */
1546 int prom_update_property(struct device_node *np,
1547 			 struct property *newprop,
1548 			 struct property *oldprop)
1549 {
1550 	struct property **next;
1551 	unsigned long flags;
1552 	int found = 0;
1553 
1554 	write_lock_irqsave(&devtree_lock, flags);
1555 	next = &np->properties;
1556 	while (*next) {
1557 		if (*next == oldprop) {
1558 			/* found the node */
1559 			newprop->next = oldprop->next;
1560 			*next = newprop;
1561 			oldprop->next = np->deadprops;
1562 			np->deadprops = oldprop;
1563 			found = 1;
1564 			break;
1565 		}
1566 		next = &(*next)->next;
1567 	}
1568 	write_unlock_irqrestore(&devtree_lock, flags);
1569 
1570 	if (!found)
1571 		return -ENODEV;
1572 
1573 #ifdef CONFIG_PROC_DEVICETREE
1574 	/* try to add to proc as well if it was initialized */
1575 	if (np->pde)
1576 		proc_device_tree_update_prop(np->pde, newprop, oldprop);
1577 #endif /* CONFIG_PROC_DEVICETREE */
1578 
1579 	return 0;
1580 }
1581 
1582 
1583 /* Find the device node for a given logical cpu number, also returns the cpu
1584  * local thread number (index in ibm,interrupt-server#s) if relevant and
1585  * asked for (non NULL)
1586  */
1587 struct device_node *of_get_cpu_node(int cpu, unsigned int *thread)
1588 {
1589 	int hardid;
1590 	struct device_node *np;
1591 
1592 	hardid = get_hard_smp_processor_id(cpu);
1593 
1594 	for_each_node_by_type(np, "cpu") {
1595 		const u32 *intserv;
1596 		unsigned int plen, t;
1597 
1598 		/* Check for ibm,ppc-interrupt-server#s. If it doesn't exist
1599 		 * fallback to "reg" property and assume no threads
1600 		 */
1601 		intserv = of_get_property(np, "ibm,ppc-interrupt-server#s",
1602 				&plen);
1603 		if (intserv == NULL) {
1604 			const u32 *reg = of_get_property(np, "reg", NULL);
1605 			if (reg == NULL)
1606 				continue;
1607 			if (*reg == hardid) {
1608 				if (thread)
1609 					*thread = 0;
1610 				return np;
1611 			}
1612 		} else {
1613 			plen /= sizeof(u32);
1614 			for (t = 0; t < plen; t++) {
1615 				if (hardid == intserv[t]) {
1616 					if (thread)
1617 						*thread = t;
1618 					return np;
1619 				}
1620 			}
1621 		}
1622 	}
1623 	return NULL;
1624 }
1625 EXPORT_SYMBOL(of_get_cpu_node);
1626 
1627 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
1628 static struct debugfs_blob_wrapper flat_dt_blob;
1629 
1630 static int __init export_flat_device_tree(void)
1631 {
1632 	struct dentry *d;
1633 
1634 	flat_dt_blob.data = initial_boot_params;
1635 	flat_dt_blob.size = initial_boot_params->totalsize;
1636 
1637 	d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
1638 				powerpc_debugfs_root, &flat_dt_blob);
1639 	if (!d)
1640 		return 1;
1641 
1642 	return 0;
1643 }
1644 __initcall(export_flat_device_tree);
1645 #endif
1646