Merge commit 'v2.6.31.12' into mini2440-stable-v2.6.31
[linux-2.6/mini2440.git] / arch / microblaze / kernel / prom.c
blobc005cc6f1aaf7f5703fb58219ddba588dc4127e4
1 /*
2 * Procedures for creating, accessing and interpreting the device tree.
4 * Paul Mackerras August 1996.
5 * Copyright (C) 1996-2005 Paul Mackerras.
7 * Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
8 * {engebret|bergner}@us.ibm.com
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.
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>
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>
42 #include <asm/sections.h>
43 #include <asm/pci-bridge.h>
45 static int __initdata dt_root_addr_cells;
46 static int __initdata dt_root_size_cells;
48 typedef u32 cell_t;
50 static struct boot_param_header *initial_boot_params;
52 /* export that to outside world */
53 struct device_node *of_chosen;
55 static inline char *find_flat_dt_string(u32 offset)
57 return ((char *)initial_boot_params) +
58 initial_boot_params->off_dt_strings + offset;
61 /**
62 * This function is used to scan the flattened device-tree, it is
63 * used to extract the memory informations at boot before we can
64 * unflatten the tree
66 int __init of_scan_flat_dt(int (*it)(unsigned long node,
67 const char *uname, int depth,
68 void *data),
69 void *data)
71 unsigned long p = ((unsigned long)initial_boot_params) +
72 initial_boot_params->off_dt_struct;
73 int rc = 0;
74 int depth = -1;
76 do {
77 u32 tag = *((u32 *)p);
78 char *pathp;
80 p += 4;
81 if (tag == OF_DT_END_NODE) {
82 depth--;
83 continue;
85 if (tag == OF_DT_NOP)
86 continue;
87 if (tag == OF_DT_END)
88 break;
89 if (tag == OF_DT_PROP) {
90 u32 sz = *((u32 *)p);
91 p += 8;
92 if (initial_boot_params->version < 0x10)
93 p = _ALIGN(p, sz >= 8 ? 8 : 4);
94 p += sz;
95 p = _ALIGN(p, 4);
96 continue;
98 if (tag != OF_DT_BEGIN_NODE) {
99 printk(KERN_WARNING "Invalid tag %x scanning flattened"
100 " device tree !\n", tag);
101 return -EINVAL;
103 depth++;
104 pathp = (char *)p;
105 p = _ALIGN(p + strlen(pathp) + 1, 4);
106 if ((*pathp) == '/') {
107 char *lp, *np;
108 for (lp = NULL, np = pathp; *np; np++)
109 if ((*np) == '/')
110 lp = np+1;
111 if (lp != NULL)
112 pathp = lp;
114 rc = it(p, pathp, depth, data);
115 if (rc != 0)
116 break;
117 } while (1);
119 return rc;
122 unsigned long __init of_get_flat_dt_root(void)
124 unsigned long p = ((unsigned long)initial_boot_params) +
125 initial_boot_params->off_dt_struct;
127 while (*((u32 *)p) == OF_DT_NOP)
128 p += 4;
129 BUG_ON(*((u32 *)p) != OF_DT_BEGIN_NODE);
130 p += 4;
131 return _ALIGN(p + strlen((char *)p) + 1, 4);
135 * This function can be used within scan_flattened_dt callback to get
136 * access to properties
138 void *__init of_get_flat_dt_prop(unsigned long node, const char *name,
139 unsigned long *size)
141 unsigned long p = node;
143 do {
144 u32 tag = *((u32 *)p);
145 u32 sz, noff;
146 const char *nstr;
148 p += 4;
149 if (tag == OF_DT_NOP)
150 continue;
151 if (tag != OF_DT_PROP)
152 return NULL;
154 sz = *((u32 *)p);
155 noff = *((u32 *)(p + 4));
156 p += 8;
157 if (initial_boot_params->version < 0x10)
158 p = _ALIGN(p, sz >= 8 ? 8 : 4);
160 nstr = find_flat_dt_string(noff);
161 if (nstr == NULL) {
162 printk(KERN_WARNING "Can't find property index"
163 " name !\n");
164 return NULL;
166 if (strcmp(name, nstr) == 0) {
167 if (size)
168 *size = sz;
169 return (void *)p;
171 p += sz;
172 p = _ALIGN(p, 4);
173 } while (1);
176 int __init of_flat_dt_is_compatible(unsigned long node, const char *compat)
178 const char *cp;
179 unsigned long cplen, l;
181 cp = of_get_flat_dt_prop(node, "compatible", &cplen);
182 if (cp == NULL)
183 return 0;
184 while (cplen > 0) {
185 if (strncasecmp(cp, compat, strlen(compat)) == 0)
186 return 1;
187 l = strlen(cp) + 1;
188 cp += l;
189 cplen -= l;
192 return 0;
195 static void *__init unflatten_dt_alloc(unsigned long *mem, unsigned long size,
196 unsigned long align)
198 void *res;
200 *mem = _ALIGN(*mem, align);
201 res = (void *)*mem;
202 *mem += size;
204 return res;
207 static unsigned long __init unflatten_dt_node(unsigned long mem,
208 unsigned long *p,
209 struct device_node *dad,
210 struct device_node ***allnextpp,
211 unsigned long fpsize)
213 struct device_node *np;
214 struct property *pp, **prev_pp = NULL;
215 char *pathp;
216 u32 tag;
217 unsigned int l, allocl;
218 int has_name = 0;
219 int new_format = 0;
221 tag = *((u32 *)(*p));
222 if (tag != OF_DT_BEGIN_NODE) {
223 printk("Weird tag at start of node: %x\n", tag);
224 return mem;
226 *p += 4;
227 pathp = (char *)*p;
228 l = allocl = strlen(pathp) + 1;
229 *p = _ALIGN(*p + l, 4);
231 /* version 0x10 has a more compact unit name here instead of the full
232 * path. we accumulate the full path size using "fpsize", we'll rebuild
233 * it later. We detect this because the first character of the name is
234 * not '/'.
236 if ((*pathp) != '/') {
237 new_format = 1;
238 if (fpsize == 0) {
239 /* root node: special case. fpsize accounts for path
240 * plus terminating zero. root node only has '/', so
241 * fpsize should be 2, but we want to avoid the first
242 * level nodes to have two '/' so we use fpsize 1 here
244 fpsize = 1;
245 allocl = 2;
246 } else {
247 /* account for '/' and path size minus terminal 0
248 * already in 'l'
250 fpsize += l;
251 allocl = fpsize;
255 np = unflatten_dt_alloc(&mem, sizeof(struct device_node) + allocl,
256 __alignof__(struct device_node));
257 if (allnextpp) {
258 memset(np, 0, sizeof(*np));
259 np->full_name = ((char *)np) + sizeof(struct device_node);
260 if (new_format) {
261 char *p2 = np->full_name;
262 /* rebuild full path for new format */
263 if (dad && dad->parent) {
264 strcpy(p2, dad->full_name);
265 #ifdef DEBUG
266 if ((strlen(p2) + l + 1) != allocl) {
267 pr_debug("%s: p: %d, l: %d, a: %d\n",
268 pathp, (int)strlen(p2),
269 l, allocl);
271 #endif
272 p2 += strlen(p2);
274 *(p2++) = '/';
275 memcpy(p2, pathp, l);
276 } else
277 memcpy(np->full_name, pathp, l);
278 prev_pp = &np->properties;
279 **allnextpp = np;
280 *allnextpp = &np->allnext;
281 if (dad != NULL) {
282 np->parent = dad;
283 /* we temporarily use the next field as `last_child'*/
284 if (dad->next == NULL)
285 dad->child = np;
286 else
287 dad->next->sibling = np;
288 dad->next = np;
290 kref_init(&np->kref);
292 while (1) {
293 u32 sz, noff;
294 char *pname;
296 tag = *((u32 *)(*p));
297 if (tag == OF_DT_NOP) {
298 *p += 4;
299 continue;
301 if (tag != OF_DT_PROP)
302 break;
303 *p += 4;
304 sz = *((u32 *)(*p));
305 noff = *((u32 *)((*p) + 4));
306 *p += 8;
307 if (initial_boot_params->version < 0x10)
308 *p = _ALIGN(*p, sz >= 8 ? 8 : 4);
310 pname = find_flat_dt_string(noff);
311 if (pname == NULL) {
312 printk(KERN_INFO
313 "Can't find property name in list !\n");
314 break;
316 if (strcmp(pname, "name") == 0)
317 has_name = 1;
318 l = strlen(pname) + 1;
319 pp = unflatten_dt_alloc(&mem, sizeof(struct property),
320 __alignof__(struct property));
321 if (allnextpp) {
322 if (strcmp(pname, "linux,phandle") == 0) {
323 np->node = *((u32 *)*p);
324 if (np->linux_phandle == 0)
325 np->linux_phandle = np->node;
327 if (strcmp(pname, "ibm,phandle") == 0)
328 np->linux_phandle = *((u32 *)*p);
329 pp->name = pname;
330 pp->length = sz;
331 pp->value = (void *)*p;
332 *prev_pp = pp;
333 prev_pp = &pp->next;
335 *p = _ALIGN((*p) + sz, 4);
337 /* with version 0x10 we may not have the name property, recreate
338 * it here from the unit name if absent
340 if (!has_name) {
341 char *p1 = pathp, *ps = pathp, *pa = NULL;
342 int sz;
344 while (*p1) {
345 if ((*p1) == '@')
346 pa = p1;
347 if ((*p1) == '/')
348 ps = p1 + 1;
349 p1++;
351 if (pa < ps)
352 pa = p1;
353 sz = (pa - ps) + 1;
354 pp = unflatten_dt_alloc(&mem, sizeof(struct property) + sz,
355 __alignof__(struct property));
356 if (allnextpp) {
357 pp->name = "name";
358 pp->length = sz;
359 pp->value = pp + 1;
360 *prev_pp = pp;
361 prev_pp = &pp->next;
362 memcpy(pp->value, ps, sz - 1);
363 ((char *)pp->value)[sz - 1] = 0;
364 pr_debug("fixed up name for %s -> %s\n", pathp,
365 (char *)pp->value);
368 if (allnextpp) {
369 *prev_pp = NULL;
370 np->name = of_get_property(np, "name", NULL);
371 np->type = of_get_property(np, "device_type", NULL);
373 if (!np->name)
374 np->name = "<NULL>";
375 if (!np->type)
376 np->type = "<NULL>";
378 while (tag == OF_DT_BEGIN_NODE) {
379 mem = unflatten_dt_node(mem, p, np, allnextpp, fpsize);
380 tag = *((u32 *)(*p));
382 if (tag != OF_DT_END_NODE) {
383 printk(KERN_INFO "Weird tag at end of node: %x\n", tag);
384 return mem;
386 *p += 4;
387 return mem;
391 * unflattens the device-tree passed by the firmware, creating the
392 * tree of struct device_node. It also fills the "name" and "type"
393 * pointers of the nodes so the normal device-tree walking functions
394 * can be used (this used to be done by finish_device_tree)
396 void __init unflatten_device_tree(void)
398 unsigned long start, mem, size;
399 struct device_node **allnextp = &allnodes;
401 pr_debug(" -> unflatten_device_tree()\n");
403 /* First pass, scan for size */
404 start = ((unsigned long)initial_boot_params) +
405 initial_boot_params->off_dt_struct;
406 size = unflatten_dt_node(0, &start, NULL, NULL, 0);
407 size = (size | 3) + 1;
409 pr_debug(" size is %lx, allocating...\n", size);
411 /* Allocate memory for the expanded device tree */
412 mem = lmb_alloc(size + 4, __alignof__(struct device_node));
413 mem = (unsigned long) __va(mem);
415 ((u32 *)mem)[size / 4] = 0xdeadbeef;
417 pr_debug(" unflattening %lx...\n", mem);
419 /* Second pass, do actual unflattening */
420 start = ((unsigned long)initial_boot_params) +
421 initial_boot_params->off_dt_struct;
422 unflatten_dt_node(mem, &start, NULL, &allnextp, 0);
423 if (*((u32 *)start) != OF_DT_END)
424 printk(KERN_WARNING "Weird tag at end of tree: %08x\n",
425 *((u32 *)start));
426 if (((u32 *)mem)[size / 4] != 0xdeadbeef)
427 printk(KERN_WARNING "End of tree marker overwritten: %08x\n",
428 ((u32 *)mem)[size / 4]);
429 *allnextp = NULL;
431 /* Get pointer to OF "/chosen" node for use everywhere */
432 of_chosen = of_find_node_by_path("/chosen");
433 if (of_chosen == NULL)
434 of_chosen = of_find_node_by_path("/chosen@0");
436 pr_debug(" <- unflatten_device_tree()\n");
439 #define early_init_dt_scan_drconf_memory(node) 0
441 static int __init early_init_dt_scan_cpus(unsigned long node,
442 const char *uname, int depth,
443 void *data)
445 static int logical_cpuid;
446 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
447 const u32 *intserv;
448 int i, nthreads;
449 int found = 0;
451 /* We are scanning "cpu" nodes only */
452 if (type == NULL || strcmp(type, "cpu") != 0)
453 return 0;
455 /* Get physical cpuid */
456 intserv = of_get_flat_dt_prop(node, "reg", NULL);
457 nthreads = 1;
460 * Now see if any of these threads match our boot cpu.
461 * NOTE: This must match the parsing done in smp_setup_cpu_maps.
463 for (i = 0; i < nthreads; i++) {
465 * version 2 of the kexec param format adds the phys cpuid of
466 * booted proc.
468 if (initial_boot_params && initial_boot_params->version >= 2) {
469 if (intserv[i] ==
470 initial_boot_params->boot_cpuid_phys) {
471 found = 1;
472 break;
474 } else {
476 * Check if it's the boot-cpu, set it's hw index now,
477 * unfortunately this format did not support booting
478 * off secondary threads.
480 if (of_get_flat_dt_prop(node,
481 "linux,boot-cpu", NULL) != NULL) {
482 found = 1;
483 break;
487 #ifdef CONFIG_SMP
488 /* logical cpu id is always 0 on UP kernels */
489 logical_cpuid++;
490 #endif
493 if (found) {
494 pr_debug("boot cpu: logical %d physical %d\n", logical_cpuid,
495 intserv[i]);
496 boot_cpuid = logical_cpuid;
499 return 0;
502 #ifdef CONFIG_BLK_DEV_INITRD
503 static void __init early_init_dt_check_for_initrd(unsigned long node)
505 unsigned long l;
506 u32 *prop;
508 pr_debug("Looking for initrd properties... ");
510 prop = of_get_flat_dt_prop(node, "linux,initrd-start", &l);
511 if (prop) {
512 initrd_start = (unsigned long)
513 __va((u32)of_read_ulong(prop, l/4));
515 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
516 if (prop) {
517 initrd_end = (unsigned long)
518 __va((u32)of_read_ulong(prop, 1/4));
519 initrd_below_start_ok = 1;
520 } else {
521 initrd_start = 0;
525 pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n",
526 initrd_start, initrd_end);
528 #else
529 static inline void early_init_dt_check_for_initrd(unsigned long node)
532 #endif /* CONFIG_BLK_DEV_INITRD */
534 static int __init early_init_dt_scan_chosen(unsigned long node,
535 const char *uname, int depth, void *data)
537 unsigned long l;
538 char *p;
540 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
542 if (depth != 1 ||
543 (strcmp(uname, "chosen") != 0 &&
544 strcmp(uname, "chosen@0") != 0))
545 return 0;
547 #ifdef CONFIG_KEXEC
548 lprop = (u64 *)of_get_flat_dt_prop(node,
549 "linux,crashkernel-base", NULL);
550 if (lprop)
551 crashk_res.start = *lprop;
553 lprop = (u64 *)of_get_flat_dt_prop(node,
554 "linux,crashkernel-size", NULL);
555 if (lprop)
556 crashk_res.end = crashk_res.start + *lprop - 1;
557 #endif
559 early_init_dt_check_for_initrd(node);
561 /* Retreive command line */
562 p = of_get_flat_dt_prop(node, "bootargs", &l);
563 if (p != NULL && l > 0)
564 strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
566 #ifdef CONFIG_CMDLINE
567 #ifndef CONFIG_CMDLINE_FORCE
568 if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
569 #endif
570 strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
571 #endif /* CONFIG_CMDLINE */
573 pr_debug("Command line is: %s\n", cmd_line);
575 /* break now */
576 return 1;
579 static int __init early_init_dt_scan_root(unsigned long node,
580 const char *uname, int depth, void *data)
582 u32 *prop;
584 if (depth != 0)
585 return 0;
587 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
588 dt_root_size_cells = (prop == NULL) ? 1 : *prop;
589 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
591 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
592 dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
593 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
595 /* break now */
596 return 1;
599 static u64 __init dt_mem_next_cell(int s, cell_t **cellp)
601 cell_t *p = *cellp;
603 *cellp = p + s;
604 return of_read_number(p, s);
607 static int __init early_init_dt_scan_memory(unsigned long node,
608 const char *uname, int depth, void *data)
610 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
611 cell_t *reg, *endp;
612 unsigned long l;
614 /* Look for the ibm,dynamic-reconfiguration-memory node */
615 /* if (depth == 1 &&
616 strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
617 return early_init_dt_scan_drconf_memory(node);
619 /* We are scanning "memory" nodes only */
620 if (type == NULL) {
622 * The longtrail doesn't have a device_type on the
623 * /memory node, so look for the node called /memory@0.
625 if (depth != 1 || strcmp(uname, "memory@0") != 0)
626 return 0;
627 } else if (strcmp(type, "memory") != 0)
628 return 0;
630 reg = (cell_t *)of_get_flat_dt_prop(node, "linux,usable-memory", &l);
631 if (reg == NULL)
632 reg = (cell_t *)of_get_flat_dt_prop(node, "reg", &l);
633 if (reg == NULL)
634 return 0;
636 endp = reg + (l / sizeof(cell_t));
638 pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
639 uname, l, reg[0], reg[1], reg[2], reg[3]);
641 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
642 u64 base, size;
644 base = dt_mem_next_cell(dt_root_addr_cells, &reg);
645 size = dt_mem_next_cell(dt_root_size_cells, &reg);
647 if (size == 0)
648 continue;
649 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
650 (unsigned long long)size);
652 lmb_add(base, size);
654 return 0;
657 #ifdef CONFIG_PHYP_DUMP
659 * phyp_dump_calculate_reserve_size() - reserve variable boot area 5% or arg
661 * Function to find the largest size we need to reserve
662 * during early boot process.
664 * It either looks for boot param and returns that OR
665 * returns larger of 256 or 5% rounded down to multiples of 256MB.
668 static inline unsigned long phyp_dump_calculate_reserve_size(void)
670 unsigned long tmp;
672 if (phyp_dump_info->reserve_bootvar)
673 return phyp_dump_info->reserve_bootvar;
675 /* divide by 20 to get 5% of value */
676 tmp = lmb_end_of_DRAM();
677 do_div(tmp, 20);
679 /* round it down in multiples of 256 */
680 tmp = tmp & ~0x0FFFFFFFUL;
682 return (tmp > PHYP_DUMP_RMR_END ? tmp : PHYP_DUMP_RMR_END);
686 * phyp_dump_reserve_mem() - reserve all not-yet-dumped mmemory
688 * This routine may reserve memory regions in the kernel only
689 * if the system is supported and a dump was taken in last
690 * boot instance or if the hardware is supported and the
691 * scratch area needs to be setup. In other instances it returns
692 * without reserving anything. The memory in case of dump being
693 * active is freed when the dump is collected (by userland tools).
695 static void __init phyp_dump_reserve_mem(void)
697 unsigned long base, size;
698 unsigned long variable_reserve_size;
700 if (!phyp_dump_info->phyp_dump_configured) {
701 printk(KERN_ERR "Phyp-dump not supported on this hardware\n");
702 return;
705 if (!phyp_dump_info->phyp_dump_at_boot) {
706 printk(KERN_INFO "Phyp-dump disabled at boot time\n");
707 return;
710 variable_reserve_size = phyp_dump_calculate_reserve_size();
712 if (phyp_dump_info->phyp_dump_is_active) {
713 /* Reserve *everything* above RMR.Area freed by userland tools*/
714 base = variable_reserve_size;
715 size = lmb_end_of_DRAM() - base;
717 /* XXX crashed_ram_end is wrong, since it may be beyond
718 * the memory_limit, it will need to be adjusted. */
719 lmb_reserve(base, size);
721 phyp_dump_info->init_reserve_start = base;
722 phyp_dump_info->init_reserve_size = size;
723 } else {
724 size = phyp_dump_info->cpu_state_size +
725 phyp_dump_info->hpte_region_size +
726 variable_reserve_size;
727 base = lmb_end_of_DRAM() - size;
728 lmb_reserve(base, size);
729 phyp_dump_info->init_reserve_start = base;
730 phyp_dump_info->init_reserve_size = size;
733 #else
734 static inline void __init phyp_dump_reserve_mem(void) {}
735 #endif /* CONFIG_PHYP_DUMP && CONFIG_PPC_RTAS */
737 #ifdef CONFIG_EARLY_PRINTK
738 /* MS this is Microblaze specifig function */
739 static int __init early_init_dt_scan_serial(unsigned long node,
740 const char *uname, int depth, void *data)
742 unsigned long l;
743 char *p;
744 int *addr;
746 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
748 /* find all serial nodes */
749 if (strncmp(uname, "serial", 6) != 0)
750 return 0;
752 early_init_dt_check_for_initrd(node);
754 /* find compatible node with uartlite */
755 p = of_get_flat_dt_prop(node, "compatible", &l);
756 if ((strncmp(p, "xlnx,xps-uartlite", 17) != 0) &&
757 (strncmp(p, "xlnx,opb-uartlite", 17) != 0))
758 return 0;
760 addr = of_get_flat_dt_prop(node, "reg", &l);
761 return *addr; /* return address */
764 /* this function is looking for early uartlite console - Microblaze specific */
765 int __init early_uartlite_console(void)
767 return of_scan_flat_dt(early_init_dt_scan_serial, NULL);
769 #endif
771 void __init early_init_devtree(void *params)
773 pr_debug(" -> early_init_devtree(%p)\n", params);
775 /* Setup flat device-tree pointer */
776 initial_boot_params = params;
778 #ifdef CONFIG_PHYP_DUMP
779 /* scan tree to see if dump occured during last boot */
780 of_scan_flat_dt(early_init_dt_scan_phyp_dump, NULL);
781 #endif
783 /* Retrieve various informations from the /chosen node of the
784 * device-tree, including the platform type, initrd location and
785 * size, TCE reserve, and more ...
787 of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
789 /* Scan memory nodes and rebuild LMBs */
790 lmb_init();
791 of_scan_flat_dt(early_init_dt_scan_root, NULL);
792 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
794 /* Save command line for /proc/cmdline and then parse parameters */
795 strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
796 parse_early_param();
798 lmb_analyze();
800 pr_debug("Phys. mem: %lx\n", (unsigned long) lmb_phys_mem_size());
802 pr_debug("Scanning CPUs ...\n");
804 /* Retreive CPU related informations from the flat tree
805 * (altivec support, boot CPU ID, ...)
807 of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
809 pr_debug(" <- early_init_devtree()\n");
813 * Indicates whether the root node has a given value in its
814 * compatible property.
816 int machine_is_compatible(const char *compat)
818 struct device_node *root;
819 int rc = 0;
821 root = of_find_node_by_path("/");
822 if (root) {
823 rc = of_device_is_compatible(root, compat);
824 of_node_put(root);
826 return rc;
828 EXPORT_SYMBOL(machine_is_compatible);
830 /*******
832 * New implementation of the OF "find" APIs, return a refcounted
833 * object, call of_node_put() when done. The device tree and list
834 * are protected by a rw_lock.
836 * Note that property management will need some locking as well,
837 * this isn't dealt with yet.
839 *******/
842 * of_find_node_by_phandle - Find a node given a phandle
843 * @handle: phandle of the node to find
845 * Returns a node pointer with refcount incremented, use
846 * of_node_put() on it when done.
848 struct device_node *of_find_node_by_phandle(phandle handle)
850 struct device_node *np;
852 read_lock(&devtree_lock);
853 for (np = allnodes; np != NULL; np = np->allnext)
854 if (np->linux_phandle == handle)
855 break;
856 of_node_get(np);
857 read_unlock(&devtree_lock);
858 return np;
860 EXPORT_SYMBOL(of_find_node_by_phandle);
863 * of_find_all_nodes - Get next node in global list
864 * @prev: Previous node or NULL to start iteration
865 * of_node_put() will be called on it
867 * Returns a node pointer with refcount incremented, use
868 * of_node_put() on it when done.
870 struct device_node *of_find_all_nodes(struct device_node *prev)
872 struct device_node *np;
874 read_lock(&devtree_lock);
875 np = prev ? prev->allnext : allnodes;
876 for (; np != NULL; np = np->allnext)
877 if (of_node_get(np))
878 break;
879 of_node_put(prev);
880 read_unlock(&devtree_lock);
881 return np;
883 EXPORT_SYMBOL(of_find_all_nodes);
886 * of_node_get - Increment refcount of a node
887 * @node: Node to inc refcount, NULL is supported to
888 * simplify writing of callers
890 * Returns node.
892 struct device_node *of_node_get(struct device_node *node)
894 if (node)
895 kref_get(&node->kref);
896 return node;
898 EXPORT_SYMBOL(of_node_get);
900 static inline struct device_node *kref_to_device_node(struct kref *kref)
902 return container_of(kref, struct device_node, kref);
906 * of_node_release - release a dynamically allocated node
907 * @kref: kref element of the node to be released
909 * In of_node_put() this function is passed to kref_put()
910 * as the destructor.
912 static void of_node_release(struct kref *kref)
914 struct device_node *node = kref_to_device_node(kref);
915 struct property *prop = node->properties;
917 /* We should never be releasing nodes that haven't been detached. */
918 if (!of_node_check_flag(node, OF_DETACHED)) {
919 printk(KERN_INFO "WARNING: Bad of_node_put() on %s\n",
920 node->full_name);
921 dump_stack();
922 kref_init(&node->kref);
923 return;
926 if (!of_node_check_flag(node, OF_DYNAMIC))
927 return;
929 while (prop) {
930 struct property *next = prop->next;
931 kfree(prop->name);
932 kfree(prop->value);
933 kfree(prop);
934 prop = next;
936 if (!prop) {
937 prop = node->deadprops;
938 node->deadprops = NULL;
941 kfree(node->full_name);
942 kfree(node->data);
943 kfree(node);
947 * of_node_put - Decrement refcount of a node
948 * @node: Node to dec refcount, NULL is supported to
949 * simplify writing of callers
952 void of_node_put(struct device_node *node)
954 if (node)
955 kref_put(&node->kref, of_node_release);
957 EXPORT_SYMBOL(of_node_put);
960 * Plug a device node into the tree and global list.
962 void of_attach_node(struct device_node *np)
964 unsigned long flags;
966 write_lock_irqsave(&devtree_lock, flags);
967 np->sibling = np->parent->child;
968 np->allnext = allnodes;
969 np->parent->child = np;
970 allnodes = np;
971 write_unlock_irqrestore(&devtree_lock, flags);
975 * "Unplug" a node from the device tree. The caller must hold
976 * a reference to the node. The memory associated with the node
977 * is not freed until its refcount goes to zero.
979 void of_detach_node(struct device_node *np)
981 struct device_node *parent;
982 unsigned long flags;
984 write_lock_irqsave(&devtree_lock, flags);
986 parent = np->parent;
987 if (!parent)
988 goto out_unlock;
990 if (allnodes == np)
991 allnodes = np->allnext;
992 else {
993 struct device_node *prev;
994 for (prev = allnodes;
995 prev->allnext != np;
996 prev = prev->allnext)
998 prev->allnext = np->allnext;
1001 if (parent->child == np)
1002 parent->child = np->sibling;
1003 else {
1004 struct device_node *prevsib;
1005 for (prevsib = np->parent->child;
1006 prevsib->sibling != np;
1007 prevsib = prevsib->sibling)
1009 prevsib->sibling = np->sibling;
1012 of_node_set_flag(np, OF_DETACHED);
1014 out_unlock:
1015 write_unlock_irqrestore(&devtree_lock, flags);
1019 * Add a property to a node
1021 int prom_add_property(struct device_node *np, struct property *prop)
1023 struct property **next;
1024 unsigned long flags;
1026 prop->next = NULL;
1027 write_lock_irqsave(&devtree_lock, flags);
1028 next = &np->properties;
1029 while (*next) {
1030 if (strcmp(prop->name, (*next)->name) == 0) {
1031 /* duplicate ! don't insert it */
1032 write_unlock_irqrestore(&devtree_lock, flags);
1033 return -1;
1035 next = &(*next)->next;
1037 *next = prop;
1038 write_unlock_irqrestore(&devtree_lock, flags);
1040 #ifdef CONFIG_PROC_DEVICETREE
1041 /* try to add to proc as well if it was initialized */
1042 if (np->pde)
1043 proc_device_tree_add_prop(np->pde, prop);
1044 #endif /* CONFIG_PROC_DEVICETREE */
1046 return 0;
1050 * Remove a property from a node. Note that we don't actually
1051 * remove it, since we have given out who-knows-how-many pointers
1052 * to the data using get-property. Instead we just move the property
1053 * to the "dead properties" list, so it won't be found any more.
1055 int prom_remove_property(struct device_node *np, struct property *prop)
1057 struct property **next;
1058 unsigned long flags;
1059 int found = 0;
1061 write_lock_irqsave(&devtree_lock, flags);
1062 next = &np->properties;
1063 while (*next) {
1064 if (*next == prop) {
1065 /* found the node */
1066 *next = prop->next;
1067 prop->next = np->deadprops;
1068 np->deadprops = prop;
1069 found = 1;
1070 break;
1072 next = &(*next)->next;
1074 write_unlock_irqrestore(&devtree_lock, flags);
1076 if (!found)
1077 return -ENODEV;
1079 #ifdef CONFIG_PROC_DEVICETREE
1080 /* try to remove the proc node as well */
1081 if (np->pde)
1082 proc_device_tree_remove_prop(np->pde, prop);
1083 #endif /* CONFIG_PROC_DEVICETREE */
1085 return 0;
1089 * Update a property in a node. Note that we don't actually
1090 * remove it, since we have given out who-knows-how-many pointers
1091 * to the data using get-property. Instead we just move the property
1092 * to the "dead properties" list, and add the new property to the
1093 * property list
1095 int prom_update_property(struct device_node *np,
1096 struct property *newprop,
1097 struct property *oldprop)
1099 struct property **next;
1100 unsigned long flags;
1101 int found = 0;
1103 write_lock_irqsave(&devtree_lock, flags);
1104 next = &np->properties;
1105 while (*next) {
1106 if (*next == oldprop) {
1107 /* found the node */
1108 newprop->next = oldprop->next;
1109 *next = newprop;
1110 oldprop->next = np->deadprops;
1111 np->deadprops = oldprop;
1112 found = 1;
1113 break;
1115 next = &(*next)->next;
1117 write_unlock_irqrestore(&devtree_lock, flags);
1119 if (!found)
1120 return -ENODEV;
1122 #ifdef CONFIG_PROC_DEVICETREE
1123 /* try to add to proc as well if it was initialized */
1124 if (np->pde)
1125 proc_device_tree_update_prop(np->pde, newprop, oldprop);
1126 #endif /* CONFIG_PROC_DEVICETREE */
1128 return 0;
1131 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
1132 static struct debugfs_blob_wrapper flat_dt_blob;
1134 static int __init export_flat_device_tree(void)
1136 struct dentry *d;
1138 flat_dt_blob.data = initial_boot_params;
1139 flat_dt_blob.size = initial_boot_params->totalsize;
1141 d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
1142 of_debugfs_root, &flat_dt_blob);
1143 if (!d)
1144 return 1;
1146 return 0;
1148 device_initcall(export_flat_device_tree);
1149 #endif