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 * Adapted for sparc64 by David S. Miller davem@davemloft.net
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; either version
15 * 2 of the License, or (at your option) any later version.
18 #include <linux/kernel.h>
19 #include <linux/types.h>
20 #include <linux/string.h>
22 #include <linux/bootmem.h>
23 #include <linux/module.h>
26 #include <asm/oplib.h>
28 static struct device_node *allnodes;
30 /* use when traversing tree through the allnext, child, sibling,
31 * or parent members of struct device_node.
33 static DEFINE_RWLOCK(devtree_lock);
35 int of_device_is_compatible(struct device_node *device, const char *compat)
40 cp = (char *) of_get_property(device, "compatible", &cplen);
44 if (strncmp(cp, compat, strlen(compat)) == 0)
53 EXPORT_SYMBOL(of_device_is_compatible);
55 struct device_node *of_get_parent(const struct device_node *node)
57 struct device_node *np;
66 EXPORT_SYMBOL(of_get_parent);
68 struct device_node *of_get_next_child(const struct device_node *node,
69 struct device_node *prev)
71 struct device_node *next;
73 next = prev ? prev->sibling : node->child;
74 for (; next != 0; next = next->sibling) {
80 EXPORT_SYMBOL(of_get_next_child);
82 struct device_node *of_find_node_by_path(const char *path)
84 struct device_node *np = allnodes;
86 for (; np != 0; np = np->allnext) {
87 if (np->full_name != 0 && strcmp(np->full_name, path) == 0)
93 EXPORT_SYMBOL(of_find_node_by_path);
95 struct device_node *of_find_node_by_phandle(phandle handle)
97 struct device_node *np;
99 for (np = allnodes; np != 0; np = np->allnext)
100 if (np->node == handle)
105 EXPORT_SYMBOL(of_find_node_by_phandle);
107 struct device_node *of_find_node_by_name(struct device_node *from,
110 struct device_node *np;
112 np = from ? from->allnext : allnodes;
113 for (; np != NULL; np = np->allnext)
114 if (np->name != NULL && strcmp(np->name, name) == 0)
119 EXPORT_SYMBOL(of_find_node_by_name);
121 struct device_node *of_find_node_by_type(struct device_node *from,
124 struct device_node *np;
126 np = from ? from->allnext : allnodes;
127 for (; np != 0; np = np->allnext)
128 if (np->type != 0 && strcmp(np->type, type) == 0)
133 EXPORT_SYMBOL(of_find_node_by_type);
135 struct device_node *of_find_compatible_node(struct device_node *from,
136 const char *type, const char *compatible)
138 struct device_node *np;
140 np = from ? from->allnext : allnodes;
141 for (; np != 0; np = np->allnext) {
143 && !(np->type != 0 && strcmp(np->type, type) == 0))
145 if (of_device_is_compatible(np, compatible))
151 EXPORT_SYMBOL(of_find_compatible_node);
153 struct property *of_find_property(struct device_node *np, const char *name,
158 for (pp = np->properties; pp != 0; pp = pp->next) {
159 if (strcmp(pp->name, name) == 0) {
167 EXPORT_SYMBOL(of_find_property);
170 * Find a property with a given name for a given node
171 * and return the value.
173 void *of_get_property(struct device_node *np, const char *name, int *lenp)
175 struct property *pp = of_find_property(np,name,lenp);
176 return pp ? pp->value : NULL;
178 EXPORT_SYMBOL(of_get_property);
180 int of_getintprop_default(struct device_node *np, const char *name, int def)
182 struct property *prop;
185 prop = of_find_property(np, name, &len);
186 if (!prop || len != 4)
189 return *(int *) prop->value;
191 EXPORT_SYMBOL(of_getintprop_default);
193 int of_n_addr_cells(struct device_node *np)
199 ip = of_get_property(np, "#address-cells", NULL);
202 } while (np->parent);
203 /* No #address-cells property for the root node, default to 2 */
206 EXPORT_SYMBOL(of_n_addr_cells);
208 int of_n_size_cells(struct device_node *np)
214 ip = of_get_property(np, "#size-cells", NULL);
217 } while (np->parent);
218 /* No #size-cells property for the root node, default to 1 */
221 EXPORT_SYMBOL(of_n_size_cells);
223 int of_set_property(struct device_node *dp, const char *name, void *val, int len)
225 struct property **prevp;
229 new_val = kmalloc(len, GFP_KERNEL);
233 memcpy(new_val, val, len);
237 write_lock(&devtree_lock);
238 prevp = &dp->properties;
240 struct property *prop = *prevp;
242 if (!strcmp(prop->name, name)) {
243 void *old_val = prop->value;
246 ret = prom_setprop(dp->node, name, val, len);
249 prop->value = new_val;
252 if (OF_IS_DYNAMIC(prop))
255 OF_MARK_DYNAMIC(prop);
261 prevp = &(*prevp)->next;
263 write_unlock(&devtree_lock);
265 /* XXX Upate procfs if necessary... */
269 EXPORT_SYMBOL(of_set_property);
271 static unsigned int prom_early_allocated;
273 static void * __init prom_early_alloc(unsigned long size)
277 ret = __alloc_bootmem(size, SMP_CACHE_BYTES, 0UL);
279 memset(ret, 0, size);
281 prom_early_allocated += size;
286 static int is_root_node(const struct device_node *dp)
291 return (dp->parent == NULL);
294 /* The following routines deal with the black magic of fully naming a
297 * Certain well known named nodes are just the simple name string.
299 * Actual devices have an address specifier appended to the base name
300 * string, like this "foo@addr". The "addr" can be in any number of
301 * formats, and the platform plus the type of the node determine the
302 * format and how it is constructed.
304 * For children of the ROOT node, the naming convention is fixed and
305 * determined by whether this is a sun4u or sun4v system.
307 * For children of other nodes, it is bus type specific. So
308 * we walk up the tree until we discover a "device_type" property
309 * we recognize and we go from there.
311 * As an example, the boot device on my workstation has a full path:
313 * /pci@1e,600000/ide@d/disk@0,0:c
315 static void __init sun4v_path_component(struct device_node *dp, char *tmp_buf)
317 struct linux_prom64_registers *regs;
318 struct property *rprop;
319 u32 high_bits, low_bits, type;
321 rprop = of_find_property(dp, "reg", NULL);
326 if (!is_root_node(dp->parent)) {
327 sprintf(tmp_buf, "%s@%x,%x",
329 (unsigned int) (regs->phys_addr >> 32UL),
330 (unsigned int) (regs->phys_addr & 0xffffffffUL));
334 type = regs->phys_addr >> 60UL;
335 high_bits = (regs->phys_addr >> 32UL) & 0x0fffffffUL;
336 low_bits = (regs->phys_addr & 0xffffffffUL);
338 if (type == 0 || type == 8) {
339 const char *prefix = (type == 0) ? "m" : "i";
342 sprintf(tmp_buf, "%s@%s%x,%x",
344 high_bits, low_bits);
346 sprintf(tmp_buf, "%s@%s%x",
350 } else if (type == 12) {
351 sprintf(tmp_buf, "%s@%x",
352 dp->name, high_bits);
356 static void __init sun4u_path_component(struct device_node *dp, char *tmp_buf)
358 struct linux_prom64_registers *regs;
359 struct property *prop;
361 prop = of_find_property(dp, "reg", NULL);
366 if (!is_root_node(dp->parent)) {
367 sprintf(tmp_buf, "%s@%x,%x",
369 (unsigned int) (regs->phys_addr >> 32UL),
370 (unsigned int) (regs->phys_addr & 0xffffffffUL));
374 prop = of_find_property(dp, "upa-portid", NULL);
376 prop = of_find_property(dp, "portid", NULL);
378 unsigned long mask = 0xffffffffUL;
380 if (tlb_type >= cheetah)
383 sprintf(tmp_buf, "%s@%x,%x",
386 (unsigned int) (regs->phys_addr & mask));
390 /* "name@slot,offset" */
391 static void __init sbus_path_component(struct device_node *dp, char *tmp_buf)
393 struct linux_prom_registers *regs;
394 struct property *prop;
396 prop = of_find_property(dp, "reg", NULL);
401 sprintf(tmp_buf, "%s@%x,%x",
407 /* "name@devnum[,func]" */
408 static void __init pci_path_component(struct device_node *dp, char *tmp_buf)
410 struct linux_prom_pci_registers *regs;
411 struct property *prop;
414 prop = of_find_property(dp, "reg", NULL);
419 devfn = (regs->phys_hi >> 8) & 0xff;
421 sprintf(tmp_buf, "%s@%x,%x",
426 sprintf(tmp_buf, "%s@%x",
432 /* "name@UPA_PORTID,offset" */
433 static void __init upa_path_component(struct device_node *dp, char *tmp_buf)
435 struct linux_prom64_registers *regs;
436 struct property *prop;
438 prop = of_find_property(dp, "reg", NULL);
444 prop = of_find_property(dp, "upa-portid", NULL);
448 sprintf(tmp_buf, "%s@%x,%x",
450 *(u32 *) prop->value,
451 (unsigned int) (regs->phys_addr & 0xffffffffUL));
455 static void __init vdev_path_component(struct device_node *dp, char *tmp_buf)
457 struct property *prop;
460 prop = of_find_property(dp, "reg", NULL);
466 sprintf(tmp_buf, "%s@%x", dp->name, *regs);
469 /* "name@addrhi,addrlo" */
470 static void __init ebus_path_component(struct device_node *dp, char *tmp_buf)
472 struct linux_prom64_registers *regs;
473 struct property *prop;
475 prop = of_find_property(dp, "reg", NULL);
481 sprintf(tmp_buf, "%s@%x,%x",
483 (unsigned int) (regs->phys_addr >> 32UL),
484 (unsigned int) (regs->phys_addr & 0xffffffffUL));
487 /* "name@bus,addr" */
488 static void __init i2c_path_component(struct device_node *dp, char *tmp_buf)
490 struct property *prop;
493 prop = of_find_property(dp, "reg", NULL);
499 /* This actually isn't right... should look at the #address-cells
500 * property of the i2c bus node etc. etc.
502 sprintf(tmp_buf, "%s@%x,%x",
503 dp->name, regs[0], regs[1]);
506 /* "name@reg0[,reg1]" */
507 static void __init usb_path_component(struct device_node *dp, char *tmp_buf)
509 struct property *prop;
512 prop = of_find_property(dp, "reg", NULL);
518 if (prop->length == sizeof(u32) || regs[1] == 1) {
519 sprintf(tmp_buf, "%s@%x",
522 sprintf(tmp_buf, "%s@%x,%x",
523 dp->name, regs[0], regs[1]);
527 /* "name@reg0reg1[,reg2reg3]" */
528 static void __init ieee1394_path_component(struct device_node *dp, char *tmp_buf)
530 struct property *prop;
533 prop = of_find_property(dp, "reg", NULL);
539 if (regs[2] || regs[3]) {
540 sprintf(tmp_buf, "%s@%08x%08x,%04x%08x",
541 dp->name, regs[0], regs[1], regs[2], regs[3]);
543 sprintf(tmp_buf, "%s@%08x%08x",
544 dp->name, regs[0], regs[1]);
548 static void __init __build_path_component(struct device_node *dp, char *tmp_buf)
550 struct device_node *parent = dp->parent;
552 if (parent != NULL) {
553 if (!strcmp(parent->type, "pci") ||
554 !strcmp(parent->type, "pciex"))
555 return pci_path_component(dp, tmp_buf);
556 if (!strcmp(parent->type, "sbus"))
557 return sbus_path_component(dp, tmp_buf);
558 if (!strcmp(parent->type, "upa"))
559 return upa_path_component(dp, tmp_buf);
560 if (!strcmp(parent->type, "ebus"))
561 return ebus_path_component(dp, tmp_buf);
562 if (!strcmp(parent->name, "usb") ||
563 !strcmp(parent->name, "hub"))
564 return usb_path_component(dp, tmp_buf);
565 if (!strcmp(parent->type, "i2c"))
566 return i2c_path_component(dp, tmp_buf);
567 if (!strcmp(parent->type, "firewire"))
568 return ieee1394_path_component(dp, tmp_buf);
569 if (!strcmp(parent->type, "virtual-devices"))
570 return vdev_path_component(dp, tmp_buf);
572 /* "isa" is handled with platform naming */
575 /* Use platform naming convention. */
576 if (tlb_type == hypervisor)
577 return sun4v_path_component(dp, tmp_buf);
579 return sun4u_path_component(dp, tmp_buf);
582 static char * __init build_path_component(struct device_node *dp)
584 char tmp_buf[64], *n;
587 __build_path_component(dp, tmp_buf);
588 if (tmp_buf[0] == '\0')
589 strcpy(tmp_buf, dp->name);
591 n = prom_early_alloc(strlen(tmp_buf) + 1);
597 static char * __init build_full_name(struct device_node *dp)
599 int len, ourlen, plen;
602 plen = strlen(dp->parent->full_name);
603 ourlen = strlen(dp->path_component_name);
604 len = ourlen + plen + 2;
606 n = prom_early_alloc(len);
607 strcpy(n, dp->parent->full_name);
608 if (!is_root_node(dp->parent)) {
609 strcpy(n + plen, "/");
612 strcpy(n + plen, dp->path_component_name);
617 static unsigned int unique_id;
619 static struct property * __init build_one_prop(phandle node, char *prev, char *special_name, void *special_val, int special_len)
621 static struct property *tmp = NULL;
626 memset(p, 0, sizeof(*p) + 32);
629 p = prom_early_alloc(sizeof(struct property) + 32);
630 p->unique_id = unique_id++;
633 p->name = (char *) (p + 1);
635 strcpy(p->name, special_name);
636 p->length = special_len;
637 p->value = prom_early_alloc(special_len);
638 memcpy(p->value, special_val, special_len);
641 prom_firstprop(node, p->name);
643 prom_nextprop(node, prev, p->name);
645 if (strlen(p->name) == 0) {
649 p->length = prom_getproplen(node, p->name);
650 if (p->length <= 0) {
653 p->value = prom_early_alloc(p->length + 1);
654 prom_getproperty(node, p->name, p->value, p->length);
655 ((unsigned char *)p->value)[p->length] = '\0';
661 static struct property * __init build_prop_list(phandle node)
663 struct property *head, *tail;
665 head = tail = build_one_prop(node, NULL,
666 ".node", &node, sizeof(node));
668 tail->next = build_one_prop(node, NULL, NULL, NULL, 0);
671 tail->next = build_one_prop(node, tail->name,
679 static char * __init get_one_property(phandle node, const char *name)
681 char *buf = "<NULL>";
684 len = prom_getproplen(node, name);
686 buf = prom_early_alloc(len);
687 prom_getproperty(node, name, buf, len);
693 static struct device_node * __init create_node(phandle node)
695 struct device_node *dp;
700 dp = prom_early_alloc(sizeof(*dp));
701 dp->unique_id = unique_id++;
703 kref_init(&dp->kref);
705 dp->name = get_one_property(node, "name");
706 dp->type = get_one_property(node, "device_type");
709 /* Build interrupts later... */
711 dp->properties = build_prop_list(node);
716 static struct device_node * __init build_tree(struct device_node *parent, phandle node, struct device_node ***nextp)
718 struct device_node *dp;
720 dp = create_node(node);
723 *nextp = &dp->allnext;
726 dp->path_component_name = build_path_component(dp);
727 dp->full_name = build_full_name(dp);
729 dp->child = build_tree(dp, prom_getchild(node), nextp);
731 dp->sibling = build_tree(parent, prom_getsibling(node), nextp);
737 void __init prom_build_devicetree(void)
739 struct device_node **nextp;
741 allnodes = create_node(prom_root_node);
742 allnodes->path_component_name = "";
743 allnodes->full_name = "/";
745 nextp = &allnodes->allnext;
746 allnodes->child = build_tree(allnodes,
747 prom_getchild(allnodes->node),
749 printk("PROM: Built device tree with %u bytes of memory.\n",
750 prom_early_allocated);