Linux 2.6.30-rc8
[linux-2.6/mini2440.git] / arch / microblaze / kernel / prom.c
blob34c48718061afcdd7781e7160dcd998e0c45c025
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)__va(of_read_ulong(prop, l/4));
514 prop = of_get_flat_dt_prop(node, "linux,initrd-end", &l);
515 if (prop) {
516 initrd_end = (unsigned long)
517 __va(of_read_ulong(prop, l/4));
518 initrd_below_start_ok = 1;
519 } else {
520 initrd_start = 0;
524 pr_debug("initrd_start=0x%lx initrd_end=0x%lx\n",
525 initrd_start, initrd_end);
527 #else
528 static inline void early_init_dt_check_for_initrd(unsigned long node)
531 #endif /* CONFIG_BLK_DEV_INITRD */
533 static int __init early_init_dt_scan_chosen(unsigned long node,
534 const char *uname, int depth, void *data)
536 unsigned long l;
537 char *p;
539 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
541 if (depth != 1 ||
542 (strcmp(uname, "chosen") != 0 &&
543 strcmp(uname, "chosen@0") != 0))
544 return 0;
546 #ifdef CONFIG_KEXEC
547 lprop = (u64 *)of_get_flat_dt_prop(node,
548 "linux,crashkernel-base", NULL);
549 if (lprop)
550 crashk_res.start = *lprop;
552 lprop = (u64 *)of_get_flat_dt_prop(node,
553 "linux,crashkernel-size", NULL);
554 if (lprop)
555 crashk_res.end = crashk_res.start + *lprop - 1;
556 #endif
558 early_init_dt_check_for_initrd(node);
560 /* Retreive command line */
561 p = of_get_flat_dt_prop(node, "bootargs", &l);
562 if (p != NULL && l > 0)
563 strlcpy(cmd_line, p, min((int)l, COMMAND_LINE_SIZE));
565 #ifdef CONFIG_CMDLINE
566 if (p == NULL || l == 0 || (l == 1 && (*p) == 0))
567 strlcpy(cmd_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
568 #endif /* CONFIG_CMDLINE */
570 pr_debug("Command line is: %s\n", cmd_line);
572 /* break now */
573 return 1;
576 static int __init early_init_dt_scan_root(unsigned long node,
577 const char *uname, int depth, void *data)
579 u32 *prop;
581 if (depth != 0)
582 return 0;
584 prop = of_get_flat_dt_prop(node, "#size-cells", NULL);
585 dt_root_size_cells = (prop == NULL) ? 1 : *prop;
586 pr_debug("dt_root_size_cells = %x\n", dt_root_size_cells);
588 prop = of_get_flat_dt_prop(node, "#address-cells", NULL);
589 dt_root_addr_cells = (prop == NULL) ? 2 : *prop;
590 pr_debug("dt_root_addr_cells = %x\n", dt_root_addr_cells);
592 /* break now */
593 return 1;
596 static u64 __init dt_mem_next_cell(int s, cell_t **cellp)
598 cell_t *p = *cellp;
600 *cellp = p + s;
601 return of_read_number(p, s);
604 static int __init early_init_dt_scan_memory(unsigned long node,
605 const char *uname, int depth, void *data)
607 char *type = of_get_flat_dt_prop(node, "device_type", NULL);
608 cell_t *reg, *endp;
609 unsigned long l;
611 /* Look for the ibm,dynamic-reconfiguration-memory node */
612 /* if (depth == 1 &&
613 strcmp(uname, "ibm,dynamic-reconfiguration-memory") == 0)
614 return early_init_dt_scan_drconf_memory(node);
616 /* We are scanning "memory" nodes only */
617 if (type == NULL) {
619 * The longtrail doesn't have a device_type on the
620 * /memory node, so look for the node called /memory@0.
622 if (depth != 1 || strcmp(uname, "memory@0") != 0)
623 return 0;
624 } else if (strcmp(type, "memory") != 0)
625 return 0;
627 reg = (cell_t *)of_get_flat_dt_prop(node, "linux,usable-memory", &l);
628 if (reg == NULL)
629 reg = (cell_t *)of_get_flat_dt_prop(node, "reg", &l);
630 if (reg == NULL)
631 return 0;
633 endp = reg + (l / sizeof(cell_t));
635 pr_debug("memory scan node %s, reg size %ld, data: %x %x %x %x,\n",
636 uname, l, reg[0], reg[1], reg[2], reg[3]);
638 while ((endp - reg) >= (dt_root_addr_cells + dt_root_size_cells)) {
639 u64 base, size;
641 base = dt_mem_next_cell(dt_root_addr_cells, &reg);
642 size = dt_mem_next_cell(dt_root_size_cells, &reg);
644 if (size == 0)
645 continue;
646 pr_debug(" - %llx , %llx\n", (unsigned long long)base,
647 (unsigned long long)size);
649 lmb_add(base, size);
651 return 0;
654 #ifdef CONFIG_PHYP_DUMP
656 * phyp_dump_calculate_reserve_size() - reserve variable boot area 5% or arg
658 * Function to find the largest size we need to reserve
659 * during early boot process.
661 * It either looks for boot param and returns that OR
662 * returns larger of 256 or 5% rounded down to multiples of 256MB.
665 static inline unsigned long phyp_dump_calculate_reserve_size(void)
667 unsigned long tmp;
669 if (phyp_dump_info->reserve_bootvar)
670 return phyp_dump_info->reserve_bootvar;
672 /* divide by 20 to get 5% of value */
673 tmp = lmb_end_of_DRAM();
674 do_div(tmp, 20);
676 /* round it down in multiples of 256 */
677 tmp = tmp & ~0x0FFFFFFFUL;
679 return (tmp > PHYP_DUMP_RMR_END ? tmp : PHYP_DUMP_RMR_END);
683 * phyp_dump_reserve_mem() - reserve all not-yet-dumped mmemory
685 * This routine may reserve memory regions in the kernel only
686 * if the system is supported and a dump was taken in last
687 * boot instance or if the hardware is supported and the
688 * scratch area needs to be setup. In other instances it returns
689 * without reserving anything. The memory in case of dump being
690 * active is freed when the dump is collected (by userland tools).
692 static void __init phyp_dump_reserve_mem(void)
694 unsigned long base, size;
695 unsigned long variable_reserve_size;
697 if (!phyp_dump_info->phyp_dump_configured) {
698 printk(KERN_ERR "Phyp-dump not supported on this hardware\n");
699 return;
702 if (!phyp_dump_info->phyp_dump_at_boot) {
703 printk(KERN_INFO "Phyp-dump disabled at boot time\n");
704 return;
707 variable_reserve_size = phyp_dump_calculate_reserve_size();
709 if (phyp_dump_info->phyp_dump_is_active) {
710 /* Reserve *everything* above RMR.Area freed by userland tools*/
711 base = variable_reserve_size;
712 size = lmb_end_of_DRAM() - base;
714 /* XXX crashed_ram_end is wrong, since it may be beyond
715 * the memory_limit, it will need to be adjusted. */
716 lmb_reserve(base, size);
718 phyp_dump_info->init_reserve_start = base;
719 phyp_dump_info->init_reserve_size = size;
720 } else {
721 size = phyp_dump_info->cpu_state_size +
722 phyp_dump_info->hpte_region_size +
723 variable_reserve_size;
724 base = lmb_end_of_DRAM() - size;
725 lmb_reserve(base, size);
726 phyp_dump_info->init_reserve_start = base;
727 phyp_dump_info->init_reserve_size = size;
730 #else
731 static inline void __init phyp_dump_reserve_mem(void) {}
732 #endif /* CONFIG_PHYP_DUMP && CONFIG_PPC_RTAS */
734 #ifdef CONFIG_EARLY_PRINTK
735 /* MS this is Microblaze specifig function */
736 static int __init early_init_dt_scan_serial(unsigned long node,
737 const char *uname, int depth, void *data)
739 unsigned long l;
740 char *p;
741 int *addr;
743 pr_debug("search \"chosen\", depth: %d, uname: %s\n", depth, uname);
745 /* find all serial nodes */
746 if (strncmp(uname, "serial", 6) != 0)
747 return 0;
749 early_init_dt_check_for_initrd(node);
751 /* find compatible node with uartlite */
752 p = of_get_flat_dt_prop(node, "compatible", &l);
753 if ((strncmp(p, "xlnx,xps-uartlite", 17) != 0) &&
754 (strncmp(p, "xlnx,opb-uartlite", 17) != 0))
755 return 0;
757 addr = of_get_flat_dt_prop(node, "reg", &l);
758 return *addr; /* return address */
761 /* this function is looking for early uartlite console - Microblaze specific */
762 int __init early_uartlite_console(void)
764 return of_scan_flat_dt(early_init_dt_scan_serial, NULL);
766 #endif
768 void __init early_init_devtree(void *params)
770 pr_debug(" -> early_init_devtree(%p)\n", params);
772 /* Setup flat device-tree pointer */
773 initial_boot_params = params;
775 #ifdef CONFIG_PHYP_DUMP
776 /* scan tree to see if dump occured during last boot */
777 of_scan_flat_dt(early_init_dt_scan_phyp_dump, NULL);
778 #endif
780 /* Retrieve various informations from the /chosen node of the
781 * device-tree, including the platform type, initrd location and
782 * size, TCE reserve, and more ...
784 of_scan_flat_dt(early_init_dt_scan_chosen, NULL);
786 /* Scan memory nodes and rebuild LMBs */
787 lmb_init();
788 of_scan_flat_dt(early_init_dt_scan_root, NULL);
789 of_scan_flat_dt(early_init_dt_scan_memory, NULL);
791 /* Save command line for /proc/cmdline and then parse parameters */
792 strlcpy(boot_command_line, cmd_line, COMMAND_LINE_SIZE);
793 parse_early_param();
795 lmb_analyze();
797 pr_debug("Phys. mem: %lx\n", (unsigned long) lmb_phys_mem_size());
799 pr_debug("Scanning CPUs ...\n");
801 /* Retreive CPU related informations from the flat tree
802 * (altivec support, boot CPU ID, ...)
804 of_scan_flat_dt(early_init_dt_scan_cpus, NULL);
806 pr_debug(" <- early_init_devtree()\n");
810 * Indicates whether the root node has a given value in its
811 * compatible property.
813 int machine_is_compatible(const char *compat)
815 struct device_node *root;
816 int rc = 0;
818 root = of_find_node_by_path("/");
819 if (root) {
820 rc = of_device_is_compatible(root, compat);
821 of_node_put(root);
823 return rc;
825 EXPORT_SYMBOL(machine_is_compatible);
827 /*******
829 * New implementation of the OF "find" APIs, return a refcounted
830 * object, call of_node_put() when done. The device tree and list
831 * are protected by a rw_lock.
833 * Note that property management will need some locking as well,
834 * this isn't dealt with yet.
836 *******/
839 * of_find_node_by_phandle - Find a node given a phandle
840 * @handle: phandle of the node to find
842 * Returns a node pointer with refcount incremented, use
843 * of_node_put() on it when done.
845 struct device_node *of_find_node_by_phandle(phandle handle)
847 struct device_node *np;
849 read_lock(&devtree_lock);
850 for (np = allnodes; np != NULL; np = np->allnext)
851 if (np->linux_phandle == handle)
852 break;
853 of_node_get(np);
854 read_unlock(&devtree_lock);
855 return np;
857 EXPORT_SYMBOL(of_find_node_by_phandle);
860 * of_find_all_nodes - Get next node in global list
861 * @prev: Previous node or NULL to start iteration
862 * of_node_put() will be called on it
864 * Returns a node pointer with refcount incremented, use
865 * of_node_put() on it when done.
867 struct device_node *of_find_all_nodes(struct device_node *prev)
869 struct device_node *np;
871 read_lock(&devtree_lock);
872 np = prev ? prev->allnext : allnodes;
873 for (; np != NULL; np = np->allnext)
874 if (of_node_get(np))
875 break;
876 of_node_put(prev);
877 read_unlock(&devtree_lock);
878 return np;
880 EXPORT_SYMBOL(of_find_all_nodes);
883 * of_node_get - Increment refcount of a node
884 * @node: Node to inc refcount, NULL is supported to
885 * simplify writing of callers
887 * Returns node.
889 struct device_node *of_node_get(struct device_node *node)
891 if (node)
892 kref_get(&node->kref);
893 return node;
895 EXPORT_SYMBOL(of_node_get);
897 static inline struct device_node *kref_to_device_node(struct kref *kref)
899 return container_of(kref, struct device_node, kref);
903 * of_node_release - release a dynamically allocated node
904 * @kref: kref element of the node to be released
906 * In of_node_put() this function is passed to kref_put()
907 * as the destructor.
909 static void of_node_release(struct kref *kref)
911 struct device_node *node = kref_to_device_node(kref);
912 struct property *prop = node->properties;
914 /* We should never be releasing nodes that haven't been detached. */
915 if (!of_node_check_flag(node, OF_DETACHED)) {
916 printk(KERN_INFO "WARNING: Bad of_node_put() on %s\n",
917 node->full_name);
918 dump_stack();
919 kref_init(&node->kref);
920 return;
923 if (!of_node_check_flag(node, OF_DYNAMIC))
924 return;
926 while (prop) {
927 struct property *next = prop->next;
928 kfree(prop->name);
929 kfree(prop->value);
930 kfree(prop);
931 prop = next;
933 if (!prop) {
934 prop = node->deadprops;
935 node->deadprops = NULL;
938 kfree(node->full_name);
939 kfree(node->data);
940 kfree(node);
944 * of_node_put - Decrement refcount of a node
945 * @node: Node to dec refcount, NULL is supported to
946 * simplify writing of callers
949 void of_node_put(struct device_node *node)
951 if (node)
952 kref_put(&node->kref, of_node_release);
954 EXPORT_SYMBOL(of_node_put);
957 * Plug a device node into the tree and global list.
959 void of_attach_node(struct device_node *np)
961 unsigned long flags;
963 write_lock_irqsave(&devtree_lock, flags);
964 np->sibling = np->parent->child;
965 np->allnext = allnodes;
966 np->parent->child = np;
967 allnodes = np;
968 write_unlock_irqrestore(&devtree_lock, flags);
972 * "Unplug" a node from the device tree. The caller must hold
973 * a reference to the node. The memory associated with the node
974 * is not freed until its refcount goes to zero.
976 void of_detach_node(struct device_node *np)
978 struct device_node *parent;
979 unsigned long flags;
981 write_lock_irqsave(&devtree_lock, flags);
983 parent = np->parent;
984 if (!parent)
985 goto out_unlock;
987 if (allnodes == np)
988 allnodes = np->allnext;
989 else {
990 struct device_node *prev;
991 for (prev = allnodes;
992 prev->allnext != np;
993 prev = prev->allnext)
995 prev->allnext = np->allnext;
998 if (parent->child == np)
999 parent->child = np->sibling;
1000 else {
1001 struct device_node *prevsib;
1002 for (prevsib = np->parent->child;
1003 prevsib->sibling != np;
1004 prevsib = prevsib->sibling)
1006 prevsib->sibling = np->sibling;
1009 of_node_set_flag(np, OF_DETACHED);
1011 out_unlock:
1012 write_unlock_irqrestore(&devtree_lock, flags);
1016 * Add a property to a node
1018 int prom_add_property(struct device_node *np, struct property *prop)
1020 struct property **next;
1021 unsigned long flags;
1023 prop->next = NULL;
1024 write_lock_irqsave(&devtree_lock, flags);
1025 next = &np->properties;
1026 while (*next) {
1027 if (strcmp(prop->name, (*next)->name) == 0) {
1028 /* duplicate ! don't insert it */
1029 write_unlock_irqrestore(&devtree_lock, flags);
1030 return -1;
1032 next = &(*next)->next;
1034 *next = prop;
1035 write_unlock_irqrestore(&devtree_lock, flags);
1037 #ifdef CONFIG_PROC_DEVICETREE
1038 /* try to add to proc as well if it was initialized */
1039 if (np->pde)
1040 proc_device_tree_add_prop(np->pde, prop);
1041 #endif /* CONFIG_PROC_DEVICETREE */
1043 return 0;
1047 * Remove a property from a node. Note that we don't actually
1048 * remove it, since we have given out who-knows-how-many pointers
1049 * to the data using get-property. Instead we just move the property
1050 * to the "dead properties" list, so it won't be found any more.
1052 int prom_remove_property(struct device_node *np, struct property *prop)
1054 struct property **next;
1055 unsigned long flags;
1056 int found = 0;
1058 write_lock_irqsave(&devtree_lock, flags);
1059 next = &np->properties;
1060 while (*next) {
1061 if (*next == prop) {
1062 /* found the node */
1063 *next = prop->next;
1064 prop->next = np->deadprops;
1065 np->deadprops = prop;
1066 found = 1;
1067 break;
1069 next = &(*next)->next;
1071 write_unlock_irqrestore(&devtree_lock, flags);
1073 if (!found)
1074 return -ENODEV;
1076 #ifdef CONFIG_PROC_DEVICETREE
1077 /* try to remove the proc node as well */
1078 if (np->pde)
1079 proc_device_tree_remove_prop(np->pde, prop);
1080 #endif /* CONFIG_PROC_DEVICETREE */
1082 return 0;
1086 * Update a property in a node. Note that we don't actually
1087 * remove it, since we have given out who-knows-how-many pointers
1088 * to the data using get-property. Instead we just move the property
1089 * to the "dead properties" list, and add the new property to the
1090 * property list
1092 int prom_update_property(struct device_node *np,
1093 struct property *newprop,
1094 struct property *oldprop)
1096 struct property **next;
1097 unsigned long flags;
1098 int found = 0;
1100 write_lock_irqsave(&devtree_lock, flags);
1101 next = &np->properties;
1102 while (*next) {
1103 if (*next == oldprop) {
1104 /* found the node */
1105 newprop->next = oldprop->next;
1106 *next = newprop;
1107 oldprop->next = np->deadprops;
1108 np->deadprops = oldprop;
1109 found = 1;
1110 break;
1112 next = &(*next)->next;
1114 write_unlock_irqrestore(&devtree_lock, flags);
1116 if (!found)
1117 return -ENODEV;
1119 #ifdef CONFIG_PROC_DEVICETREE
1120 /* try to add to proc as well if it was initialized */
1121 if (np->pde)
1122 proc_device_tree_update_prop(np->pde, newprop, oldprop);
1123 #endif /* CONFIG_PROC_DEVICETREE */
1125 return 0;
1128 #if defined(CONFIG_DEBUG_FS) && defined(DEBUG)
1129 static struct debugfs_blob_wrapper flat_dt_blob;
1131 static int __init export_flat_device_tree(void)
1133 struct dentry *d;
1135 flat_dt_blob.data = initial_boot_params;
1136 flat_dt_blob.size = initial_boot_params->totalsize;
1138 d = debugfs_create_blob("flat-device-tree", S_IFREG | S_IRUSR,
1139 of_debugfs_root, &flat_dt_blob);
1140 if (!d)
1141 return 1;
1143 return 0;
1145 device_initcall(export_flat_device_tree);
1146 #endif