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Michal Simek12e84142009-03-27 14:25:12 +01001/*
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#include <stdarg.h>
17#include <linux/kernel.h>
18#include <linux/string.h>
19#include <linux/init.h>
20#include <linux/threads.h>
21#include <linux/spinlock.h>
22#include <linux/types.h>
23#include <linux/pci.h>
24#include <linux/stringify.h>
25#include <linux/delay.h>
26#include <linux/initrd.h>
27#include <linux/bitops.h>
28#include <linux/module.h>
29#include <linux/kexec.h>
30#include <linux/debugfs.h>
31#include <linux/irq.h>
32#include <linux/lmb.h>
33
34#include <asm/prom.h>
35#include <asm/page.h>
36#include <asm/processor.h>
37#include <asm/irq.h>
38#include <linux/io.h>
39#include <asm/system.h>
40#include <asm/mmu.h>
41#include <asm/pgtable.h>
Michal Simek12e84142009-03-27 14:25:12 +010042#include <asm/sections.h>
43#include <asm/pci-bridge.h>
44
45static int __initdata dt_root_addr_cells;
46static int __initdata dt_root_size_cells;
47
48typedef u32 cell_t;
49
Michal Simek12e84142009-03-27 14:25:12 +010050/* export that to outside world */
51struct device_node *of_chosen;
52
Michal Simek12e84142009-03-27 14:25:12 +010053static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size,
54 unsigned long align)
55{
56 void *res;
57
58 *mem = _ALIGN(*mem, align);
59 res = (void *)*mem;
60 *mem += size;
61
62 return res;
63}
64
65static unsigned long __init unflatten_dt_node(unsigned long mem,
66 unsigned long *p,
67 struct device_node *dad,
68 struct device_node ***allnextpp,
69 unsigned long fpsize)
70{
71 struct device_node *np;
72 struct property *pp, **prev_pp = NULL;
73 char *pathp;
74 u32 tag;
75 unsigned int l, allocl;
76 int has_name = 0;
77 int new_format = 0;
78
79 tag = *((u32 *)(*p));
80 if (tag != OF_DT_BEGIN_NODE) {
81 printk("Weird tag at start of node: %x\n", tag);
82 return mem;
83 }
84 *p += 4;
85 pathp = (char *)*p;
86 l = allocl = strlen(pathp) + 1;
87 *p = _ALIGN(*p + l, 4);
88
89 /* version 0x10 has a more compact unit name here instead of the full
90 * path. we accumulate the full path size using "fpsize", we'll rebuild
91 * it later. We detect this because the first character of the name is
92 * not '/'.
93 */
94 if ((*pathp) != '/') {
95 new_format = 1;
96 if (fpsize == 0) {
97 /* root node: special case. fpsize accounts for path
98 * plus terminating zero. root node only has '/', so
99 * fpsize should be 2, but we want to avoid the first
100 * level nodes to have two '/' so we use fpsize 1 here
101 */
102 fpsize = 1;
103 allocl = 2;
104 } else {
105 /* account for '/' and path size minus terminal 0
106 * already in 'l'
107 */
108 fpsize += l;
109 allocl = fpsize;
110 }
111 }
112
113 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
114 __alignof__(struct device_node));
115 if (allnextpp) {
116 memset(np, 0, sizeof(*np));
117 np->full_name = ((char *)np) + sizeof(struct device_node);
118 if (new_format) {
119 char *p2 = np->full_name;
120 /* rebuild full path for new format */
121 if (dad && dad->parent) {
122 strcpy(p2, dad->full_name);
123#ifdef DEBUG
124 if ((strlen(p2) + l + 1) != allocl) {
125 pr_debug("%s: p: %d, l: %d, a: %d\n",
126 pathp, (int)strlen(p2),
127 l, allocl);
128 }
129#endif
130 p2 += strlen(p2);
131 }
132 *(p2++) = '/';
133 memcpy(p2, pathp, l);
134 } else
135 memcpy(np->full_name, pathp, l);
136 prev_pp = &np->properties;
137 **allnextpp = np;
138 *allnextpp = &np->allnext;
139 if (dad != NULL) {
140 np->parent = dad;
141 /* we temporarily use the next field as `last_child'*/
142 if (dad->next == NULL)
143 dad->child = np;
144 else
145 dad->next->sibling = np;
146 dad->next = np;
147 }
148 kref_init(&np->kref);
149 }
150 while (1) {
151 u32 sz, noff;
152 char *pname;
153
154 tag = *((u32 *)(*p));
155 if (tag == OF_DT_NOP) {
156 *p += 4;
157 continue;
158 }
159 if (tag != OF_DT_PROP)
160 break;
161 *p += 4;
162 sz = *((u32 *)(*p));
163 noff = *((u32 *)((*p) + 4));
164 *p += 8;
165 if (initial_boot_params->version < 0x10)
166 *p = _ALIGN(*p, sz >= 8 ? 8 : 4);
167
168 pname = find_flat_dt_string(noff);
169 if (pname == NULL) {
170 printk(KERN_INFO
171 "Can't find property name in list !\n");
172 break;
173 }
174 if (strcmp(pname, "name") == 0)
175 has_name = 1;
176 l = strlen(pname) + 1;
177 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
178 __alignof__(struct property));
179 if (allnextpp) {
180 if (strcmp(pname, "linux,phandle") == 0) {
181 np->node = *((u32 *)*p);
182 if (np->linux_phandle == 0)
183 np->linux_phandle = np->node;
184 }
185 if (strcmp(pname, "ibm,phandle") == 0)
186 np->linux_phandle = *((u32 *)*p);
187 pp->name = pname;
188 pp->length = sz;
189 pp->value = (void *)*p;
190 *prev_pp = pp;
191 prev_pp = &pp->next;
192 }
193 *p = _ALIGN((*p) + sz, 4);
194 }
195 /* with version 0x10 we may not have the name property, recreate
196 * it here from the unit name if absent
197 */
198 if (!has_name) {
199 char *p1 = pathp, *ps = pathp, *pa = NULL;
200 int sz;
201
202 while (*p1) {
203 if ((*p1) == '@')
204 pa = p1;
205 if ((*p1) == '/')
206 ps = p1 + 1;
207 p1++;
208 }
209 if (pa < ps)
210 pa = p1;
211 sz = (pa - ps) + 1;
212 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
213 __alignof__(struct property));
214 if (allnextpp) {
215 pp->name = "name";
216 pp->length = sz;
217 pp->value = pp + 1;
218 *prev_pp = pp;
219 prev_pp = &pp->next;
220 memcpy(pp->value, ps, sz - 1);
221 ((char *)pp->value)[sz - 1] = 0;
222 pr_debug("fixed up name for %s -> %s\n", pathp,
223 (char *)pp->value);
224 }
225 }
226 if (allnextpp) {
227 *prev_pp = NULL;
228 np->name = of_get_property(np, "name", NULL);
229 np->type = of_get_property(np, "device_type", NULL);
230
231 if (!np->name)
232 np->name = "<NULL>";
233 if (!np->type)
234 np->type = "<NULL>";
235 }
236 while (tag == OF_DT_BEGIN_NODE) {
237 mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize);
238 tag = *((u32 *)(*p));
239 }
240 if (tag != OF_DT_END_NODE) {
241 printk(KERN_INFO "Weird tag at end of node: %x\n", tag);
242 return mem;
243 }
244 *p += 4;
245 return mem;
246}
247
248/**
249 * unflattens the device-tree passed by the firmware, creating the
250 * tree of struct device_node. It also fills the "name" and "type"
251 * pointers of the nodes so the normal device-tree walking functions
252 * can be used (this used to be done by finish_device_tree)
253 */
254void __init unflatten_device_tree(void)
255{
256 unsigned long start, mem, size;
257 struct device_node **allnextp = &allnodes;
258
259 pr_debug(" -> unflatten_device_tree()\n");
260
261 /* First pass, scan for size */
262 start = ((unsigned long)initial_boot_params) +
263 initial_boot_params->off_dt_struct;
264 size = unflatten_dt_node(0, &start, NULL, NULL, 0);
265 size = (size | 3) + 1;
266
267 pr_debug(" size is %lx, allocating...\n", size);
268
269 /* Allocate memory for the expanded device tree */
270 mem = lmb_alloc(size + 4, __alignof__(struct device_node));
271 mem = (unsigned long) __va(mem);
272
273 ((u32 *)mem)[size / 4] = 0xdeadbeef;
274
275 pr_debug(" unflattening %lx...\n", mem);
276
277 /* Second pass, do actual unflattening */
278 start = ((unsigned long)initial_boot_params) +
279 initial_boot_params->off_dt_struct;
280 unflatten_dt_node(mem, &start, NULL, &allnextp, 0);
281 if (*((u32 *)start) != OF_DT_END)
282 printk(KERN_WARNING "Weird tag at end of tree: %08x\n",
283 *((u32 *)start));
284 if (((u32 *)mem)[size / 4] != 0xdeadbeef)
285 printk(KERN_WARNING "End of tree marker overwritten: %08x\n",
286 ((u32 *)mem)[size / 4]);
287 *allnextp = NULL;
288
289 /* Get pointer to OF "/chosen" node for use everywhere */
290 of_chosen = of_find_node_by_path("/chosen");
291 if (of_chosen == NULL)
292 of_chosen = of_find_node_by_path("/chosen@0");
293
294 pr_debug(" <- unflatten_device_tree()\n");
295}
296
297#define early_init_dt_scan_drconf_memory(node) 0
298
299static int __init early_init_dt_scan_cpus(unsigned long node,
300 const char *uname, int depth,
301 void *data)
302{
303 static int logical_cpuid;
304 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
305 const u32 *intserv;
306 int i, nthreads;
307 int found = 0;
308
309 /* We are scanning "cpu" nodes only */
310 if (type == NULL || strcmp(type, "cpu") != 0)
311 return 0;
312
313 /* Get physical cpuid */
314 intserv = of_get_flat_dt_prop(node, "reg", NULL);
315 nthreads = 1;
316
317 /*
318 * Now see if any of these threads match our boot cpu.
319 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
320 */
321 for (i = 0; i < nthreads; i++) {
322 /*
323 * version 2 of the kexec param format adds the phys cpuid of
324 * booted proc.
325 */
326 if (initial_boot_params && initial_boot_params->version >= 2) {
327 if (intserv[i] ==
328 initial_boot_params->boot_cpuid_phys) {
329 found = 1;
330 break;
331 }
332 } else {
333 /*
334 * Check if it's the boot-cpu, set it's hw index now,
335 * unfortunately this format did not support booting
336 * off secondary threads.
337 */
338 if (of_get_flat_dt_prop(node,
339 "linux,boot-cpu", NULL) != NULL) {
340 found = 1;
341 break;
342 }
343 }
344
345#ifdef CONFIG_SMP
346 /* logical cpu id is always 0 on UP kernels */
347 logical_cpuid++;
348#endif
349 }
350
351 if (found) {
352 pr_debug("boot cpu: logical %d physical %d\n", logical_cpuid,
353 intserv[i]);
354 boot_cpuid = logical_cpuid;
355 }
356
357 return 0;
358}
359
360#ifdef CONFIG_BLK_DEV_INITRD
361static void __init early_init_dt_check_for_initrd(unsigned long node)
362{
363 unsigned long l;
364 u32 *prop;
365
366 pr_debug("Looking for initrd properties... ");
367
368 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l);
369 if (prop) {
Michal Simekb9479e62009-05-21 16:33:07 +0200370 initrd_start = (unsigned long)
371 __va((u32)of_read_ulong(prop, l/4));
Michal Simek12e84142009-03-27 14:25:12 +0100372
373 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
374 if (prop) {
375 initrd_end = (unsigned long)
Michal Simekb9479e62009-05-21 16:33:07 +0200376 __va((u32)of_read_ulong(prop, 1/4));
Michal Simek12e84142009-03-27 14:25:12 +0100377 initrd_below_start_ok = 1;
378 } else {
379 initrd_start = 0;
380 }
381 }
382
383 pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n",
384 initrd_start, initrd_end);
385}
386#else
387static inline void early_init_dt_check_for_initrd(unsigned long node)
388{
389}
390#endif /* CONFIG_BLK_DEV_INITRD */
391
392static int __init early_init_dt_scan_chosen(unsigned long node,
393 const char *uname, int depth, void *data)
394{
395 unsigned long l;
396 char *p;
397
398 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
399
400 if (depth != 1 ||
401 (strcmp(uname, "chosen") != 0 &&
402 strcmp(uname, "chosen@0") != 0))
403 return 0;
404
405#ifdef CONFIG_KEXEC
406 lprop = (u64 *)of_get_flat_dt_prop(node,
407 "linux,crashkernel-base", NULL);
408 if (lprop)
409 crashk_res.start = *lprop;
410
411 lprop = (u64 *)of_get_flat_dt_prop(node,
412 "linux,crashkernel-size", NULL);
413 if (lprop)
414 crashk_res.end = crashk_res.start + *lprop - 1;
415#endif
416
417 early_init_dt_check_for_initrd(node);
418
419 /* Retreive command line */
420 p = of_get_flat_dt_prop(node, "bootargs", &l);
421 if (p != NULL && l > 0)
422 strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
423
424#ifdef CONFIG_CMDLINE
Michal Simek1dff89a2009-05-21 08:20:30 +0200425#ifndef CONFIG_CMDLINE_FORCE
Michal Simek12e84142009-03-27 14:25:12 +0100426 if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
Michal Simek1dff89a2009-05-21 08:20:30 +0200427#endif
Michal Simek12e84142009-03-27 14:25:12 +0100428 strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
429#endif /* CONFIG_CMDLINE */
430
431 pr_debug("Command line is: %s\n", cmd_line);
432
433 /* break now */
434 return 1;
435}
436
437static int __init early_init_dt_scan_root(unsigned long node,
438 const char *uname, int depth, void *data)
439{
440 u32 *prop;
441
442 if (depth != 0)
443 return 0;
444
445 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
446 dt_root_size_cells = (prop == NULL) ? 1 : *prop;
447 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
448
449 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
450 dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
451 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
452
453 /* break now */
454 return 1;
455}
456
457static u64 __init dt_mem_next_cell(int s, cell_t **cellp)
458{
459 cell_t *p = *cellp;
460
461 *cellp = p + s;
462 return of_read_number(p, s);
463}
464
465static int __init early_init_dt_scan_memory(unsigned long node,
466 const char *uname, int depth, void *data)
467{
468 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
469 cell_t *reg, *endp;
470 unsigned long l;
471
472 /* Look for the ibm,dynamic-reconfiguration-memory node */
473/* if (depth == 1 &&
474 strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
475 return early_init_dt_scan_drconf_memory(node);
476*/
477 /* We are scanning "memory" nodes only */
478 if (type == NULL) {
479 /*
480 * The longtrail doesn't have a device_type on the
481 * /memory node, so look for the node called /memory@0.
482 */
483 if (depth != 1 || strcmp(uname, "memory@0") != 0)
484 return 0;
485 } else if (strcmp(type, "memory") != 0)
486 return 0;
487
488 reg = (cell_t *)of_get_flat_dt_prop(node, "linux,usable-memory", &l);
489 if (reg == NULL)
490 reg = (cell_t *)of_get_flat_dt_prop(node, "reg", &l);
491 if (reg == NULL)
492 return 0;
493
494 endp = reg + (l / sizeof(cell_t));
495
496 pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
497 uname, l, reg[0], reg[1], reg[2], reg[3]);
498
499 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
500 u64 base, size;
501
502 base = dt_mem_next_cell(dt_root_addr_cells, &reg);
503 size = dt_mem_next_cell(dt_root_size_cells, &reg);
504
505 if (size == 0)
506 continue;
507 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
508 (unsigned long long)size);
509
510 lmb_add(base, size);
511 }
512 return 0;
513}
514
515#ifdef CONFIG_PHYP_DUMP
516/**
517 * phyp_dump_calculate_reserve_size() - reserve variable boot area 5% or arg
518 *
519 * Function to find the largest size we need to reserve
520 * during early boot process.
521 *
522 * It either looks for boot param and returns that OR
523 * returns larger of 256 or 5% rounded down to multiples of 256MB.
524 *
525 */
526static inline unsigned long phyp_dump_calculate_reserve_size(void)
527{
528 unsigned long tmp;
529
530 if (phyp_dump_info->reserve_bootvar)
531 return phyp_dump_info->reserve_bootvar;
532
533 /* divide by 20 to get 5% of value */
534 tmp = lmb_end_of_DRAM();
535 do_div(tmp, 20);
536
537 /* round it down in multiples of 256 */
538 tmp = tmp & ~0x0FFFFFFFUL;
539
540 return (tmp > PHYP_DUMP_RMR_END ? tmp : PHYP_DUMP_RMR_END);
541}
542
543/**
544 * phyp_dump_reserve_mem() - reserve all not-yet-dumped mmemory
545 *
546 * This routine may reserve memory regions in the kernel only
547 * if the system is supported and a dump was taken in last
548 * boot instance or if the hardware is supported and the
549 * scratch area needs to be setup. In other instances it returns
550 * without reserving anything. The memory in case of dump being
551 * active is freed when the dump is collected (by userland tools).
552 */
553static void __init phyp_dump_reserve_mem(void)
554{
555 unsigned long base, size;
556 unsigned long variable_reserve_size;
557
558 if (!phyp_dump_info->phyp_dump_configured) {
559 printk(KERN_ERR "Phyp-dump not supported on this hardware\n");
560 return;
561 }
562
563 if (!phyp_dump_info->phyp_dump_at_boot) {
564 printk(KERN_INFO "Phyp-dump disabled at boot time\n");
565 return;
566 }
567
568 variable_reserve_size = phyp_dump_calculate_reserve_size();
569
570 if (phyp_dump_info->phyp_dump_is_active) {
571 /* Reserve *everything* above RMR.Area freed by userland tools*/
572 base = variable_reserve_size;
573 size = lmb_end_of_DRAM() - base;
574
575 /* XXX crashed_ram_end is wrong, since it may be beyond
576 * the memory_limit, it will need to be adjusted. */
577 lmb_reserve(base, size);
578
579 phyp_dump_info->init_reserve_start = base;
580 phyp_dump_info->init_reserve_size = size;
581 } else {
582 size = phyp_dump_info->cpu_state_size +
583 phyp_dump_info->hpte_region_size +
584 variable_reserve_size;
585 base = lmb_end_of_DRAM() - size;
586 lmb_reserve(base, size);
587 phyp_dump_info->init_reserve_start = base;
588 phyp_dump_info->init_reserve_size = size;
589 }
590}
591#else
592static inline void __init phyp_dump_reserve_mem(void) {}
593#endif /* CONFIG_PHYP_DUMP && CONFIG_PPC_RTAS */
594
595#ifdef CONFIG_EARLY_PRINTK
596/* MS this is Microblaze specifig function */
597static int __init early_init_dt_scan_serial(unsigned long node,
598 const char *uname, int depth, void *data)
599{
600 unsigned long l;
601 char *p;
602 int *addr;
603
604 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
605
606/* find all serial nodes */
607 if (strncmp(uname, "serial", 6) != 0)
608 return 0;
609
610 early_init_dt_check_for_initrd(node);
611
612/* find compatible node with uartlite */
613 p = of_get_flat_dt_prop(node, "compatible", &l);
614 if ((strncmp(p, "xlnx,xps-uartlite", 17) != 0) &&
615 (strncmp(p, "xlnx,opb-uartlite", 17) != 0))
616 return 0;
617
618 addr = of_get_flat_dt_prop(node, "reg", &l);
619 return *addr; /* return address */
620}
621
622/* this function is looking for early uartlite console - Microblaze specific */
623int __init early_uartlite_console(void)
624{
625 return of_scan_flat_dt(early_init_dt_scan_serial, NULL);
626}
627#endif
628
629void __init early_init_devtree(void *params)
630{
631 pr_debug(" -> early_init_devtree(%p)\n", params);
632
633 /* Setup flat device-tree pointer */
634 initial_boot_params = params;
635
636#ifdef CONFIG_PHYP_DUMP
637 /* scan tree to see if dump occured during last boot */
638 of_scan_flat_dt(early_init_dt_scan_phyp_dump, NULL);
639#endif
640
641 /* Retrieve various informations from the /chosen node of the
642 * device-tree, including the platform type, initrd location and
643 * size, TCE reserve, and more ...
644 */
645 of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
646
647 /* Scan memory nodes and rebuild LMBs */
648 lmb_init();
649 of_scan_flat_dt(early_init_dt_scan_root, NULL);
650 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
651
652 /* Save command line for /proc/cmdline and then parse parameters */
653 strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
654 parse_early_param();
655
656 lmb_analyze();
657
658 pr_debug("Phys. mem: %lx\n", (unsigned long) lmb_phys_mem_size());
659
660 pr_debug("Scanning CPUs ...\n");
661
662 /* Retreive CPU related informations from the flat tree
663 * (altivec support, boot CPU ID, ...)
664 */
665 of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
666
667 pr_debug(" <- early_init_devtree()\n");
668}
669
670/**
671 * Indicates whether the root node has a given value in its
672 * compatible property.
673 */
674int machine_is_compatible(const char *compat)
675{
676 struct device_node *root;
677 int rc = 0;
678
679 root = of_find_node_by_path("/");
680 if (root) {
681 rc = of_device_is_compatible(root, compat);
682 of_node_put(root);
683 }
684 return rc;
685}
686EXPORT_SYMBOL(machine_is_compatible);
687
688/*******
689 *
690 * New implementation of the OF "find" APIs, return a refcounted
691 * object, call of_node_put() when done. The device tree and list
692 * are protected by a rw_lock.
693 *
694 * Note that property management will need some locking as well,
695 * this isn't dealt with yet.
696 *
697 *******/
698
699/**
700 * of_find_node_by_phandle - Find a node given a phandle
701 * @handle: phandle of the node to find
702 *
703 * Returns a node pointer with refcount incremented, use
704 * of_node_put() on it when done.
705 */
706struct device_node *of_find_node_by_phandle(phandle handle)
707{
708 struct device_node *np;
709
710 read_lock(&devtree_lock);
711 for (np = allnodes; np != NULL; np = np->allnext)
712 if (np->linux_phandle == handle)
713 break;
714 of_node_get(np);
715 read_unlock(&devtree_lock);
716 return np;
717}
718EXPORT_SYMBOL(of_find_node_by_phandle);
719
720/**
Michal Simek12e84142009-03-27 14:25:12 +0100721 * of_node_get - Increment refcount of a node
722 * @node: Node to inc refcount, NULL is supported to
723 * simplify writing of callers
724 *
725 * Returns node.
726 */
727struct device_node *of_node_get(struct device_node *node)
728{
729 if (node)
730 kref_get(&node->kref);
731 return node;
732}
733EXPORT_SYMBOL(of_node_get);
734
735static inline struct device_node *kref_to_device_node(struct kref *kref)
736{
737 return container_of(kref, struct device_node, kref);
738}
739
740/**
741 * of_node_release - release a dynamically allocated node
742 * @kref: kref element of the node to be released
743 *
744 * In of_node_put() this function is passed to kref_put()
745 * as the destructor.
746 */
747static void of_node_release(struct kref *kref)
748{
749 struct device_node *node = kref_to_device_node(kref);
750 struct property *prop = node->properties;
751
752 /* We should never be releasing nodes that haven't been detached. */
753 if (!of_node_check_flag(node, OF_DETACHED)) {
754 printk(KERN_INFO "WARNING: Bad of_node_put() on %s\n",
755 node->full_name);
756 dump_stack();
757 kref_init(&node->kref);
758 return;
759 }
760
761 if (!of_node_check_flag(node, OF_DYNAMIC))
762 return;
763
764 while (prop) {
765 struct property *next = prop->next;
766 kfree(prop->name);
767 kfree(prop->value);
768 kfree(prop);
769 prop = next;
770
771 if (!prop) {
772 prop = node->deadprops;
773 node->deadprops = NULL;
774 }
775 }
776 kfree(node->full_name);
777 kfree(node->data);
778 kfree(node);
779}
780
781/**
782 * of_node_put - Decrement refcount of a node
783 * @node: Node to dec refcount, NULL is supported to
784 * simplify writing of callers
785 *
786 */
787void of_node_put(struct device_node *node)
788{
789 if (node)
790 kref_put(&node->kref, of_node_release);
791}
792EXPORT_SYMBOL(of_node_put);
793
794/*
795 * Plug a device node into the tree and global list.
796 */
797void of_attach_node(struct device_node *np)
798{
799 unsigned long flags;
800
801 write_lock_irqsave(&devtree_lock, flags);
802 np->sibling = np->parent->child;
803 np->allnext = allnodes;
804 np->parent->child = np;
805 allnodes = np;
806 write_unlock_irqrestore(&devtree_lock, flags);
807}
808
809/*
810 * "Unplug" a node from the device tree. The caller must hold
811 * a reference to the node. The memory associated with the node
812 * is not freed until its refcount goes to zero.
813 */
814void of_detach_node(struct device_node *np)
815{
816 struct device_node *parent;
817 unsigned long flags;
818
819 write_lock_irqsave(&devtree_lock, flags);
820
821 parent = np->parent;
822 if (!parent)
823 goto out_unlock;
824
825 if (allnodes == np)
826 allnodes = np->allnext;
827 else {
828 struct device_node *prev;
829 for (prev = allnodes;
830 prev->allnext != np;
831 prev = prev->allnext)
832 ;
833 prev->allnext = np->allnext;
834 }
835
836 if (parent->child == np)
837 parent->child = np->sibling;
838 else {
839 struct device_node *prevsib;
840 for (prevsib = np->parent->child;
841 prevsib->sibling != np;
842 prevsib = prevsib->sibling)
843 ;
844 prevsib->sibling = np->sibling;
845 }
846
847 of_node_set_flag(np, OF_DETACHED);
848
849out_unlock:
850 write_unlock_irqrestore(&devtree_lock, flags);
851}
852
853/*
854 * Add a property to a node
855 */
856int prom_add_property(struct device_node *np, struct property *prop)
857{
858 struct property **next;
859 unsigned long flags;
860
861 prop->next = NULL;
862 write_lock_irqsave(&devtree_lock, flags);
863 next = &np->properties;
864 while (*next) {
865 if (strcmp(prop->name, (*next)->name) == 0) {
866 /* duplicate ! don't insert it */
867 write_unlock_irqrestore(&devtree_lock, flags);
868 return -1;
869 }
870 next = &(*next)->next;
871 }
872 *next = prop;
873 write_unlock_irqrestore(&devtree_lock, flags);
874
875#ifdef CONFIG_PROC_DEVICETREE
876 /* try to add to proc as well if it was initialized */
877 if (np->pde)
878 proc_device_tree_add_prop(np->pde, prop);
879#endif /* CONFIG_PROC_DEVICETREE */
880
881 return 0;
882}
883
884/*
885 * Remove a property from a node. Note that we don't actually
886 * remove it, since we have given out who-knows-how-many pointers
887 * to the data using get-property. Instead we just move the property
888 * to the "dead properties" list, so it won't be found any more.
889 */
890int prom_remove_property(struct device_node *np, struct property *prop)
891{
892 struct property **next;
893 unsigned long flags;
894 int found = 0;
895
896 write_lock_irqsave(&devtree_lock, flags);
897 next = &np->properties;
898 while (*next) {
899 if (*next == prop) {
900 /* found the node */
901 *next = prop->next;
902 prop->next = np->deadprops;
903 np->deadprops = prop;
904 found = 1;
905 break;
906 }
907 next = &(*next)->next;
908 }
909 write_unlock_irqrestore(&devtree_lock, flags);
910
911 if (!found)
912 return -ENODEV;
913
914#ifdef CONFIG_PROC_DEVICETREE
915 /* try to remove the proc node as well */
916 if (np->pde)
917 proc_device_tree_remove_prop(np->pde, prop);
918#endif /* CONFIG_PROC_DEVICETREE */
919
920 return 0;
921}
922
923/*
924 * Update a property in a node. Note that we don't actually
925 * remove it, since we have given out who-knows-how-many pointers
926 * to the data using get-property. Instead we just move the property
927 * to the "dead properties" list, and add the new property to the
928 * property list
929 */
930int prom_update_property(struct device_node *np,
931 struct property *newprop,
932 struct property *oldprop)
933{
934 struct property **next;
935 unsigned long flags;
936 int found = 0;
937
938 write_lock_irqsave(&devtree_lock, flags);
939 next = &np->properties;
940 while (*next) {
941 if (*next == oldprop) {
942 /* found the node */
943 newprop->next = oldprop->next;
944 *next = newprop;
945 oldprop->next = np->deadprops;
946 np->deadprops = oldprop;
947 found = 1;
948 break;
949 }
950 next = &(*next)->next;
951 }
952 write_unlock_irqrestore(&devtree_lock, flags);
953
954 if (!found)
955 return -ENODEV;
956
957#ifdef CONFIG_PROC_DEVICETREE
958 /* try to add to proc as well if it was initialized */
959 if (np->pde)
960 proc_device_tree_update_prop(np->pde, newprop, oldprop);
961#endif /* CONFIG_PROC_DEVICETREE */
962
963 return 0;
964}
965
966#if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
967static struct debugfs_blob_wrapper flat_dt_blob;
968
969static int __init export_flat_device_tree(void)
970{
971 struct dentry *d;
972
973 flat_dt_blob.data = initial_boot_params;
974 flat_dt_blob.size = initial_boot_params->totalsize;
975
976 d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
977 of_debugfs_root, &flat_dt_blob);
978 if (!d)
979 return 1;
980
981 return 0;
982}
983device_initcall(export_flat_device_tree);
984#endif