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 sparc32 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>
30 static unsigned int prom_early_allocated;
32 void * __init prom_early_alloc(unsigned long size)
36 ret = __alloc_bootmem(size, SMP_CACHE_BYTES, 0UL);
40 prom_early_allocated += size;
45 static int is_root_node(const struct device_node *dp)
50 return (dp->parent == NULL);
53 /* The following routines deal with the black magic of fully naming a
56 * Certain well known named nodes are just the simple name string.
58 * Actual devices have an address specifier appended to the base name
59 * string, like this "foo@addr". The "addr" can be in any number of
60 * formats, and the platform plus the type of the node determine the
61 * format and how it is constructed.
63 * For children of the ROOT node, the naming convention is fixed and
64 * determined by whether this is a sun4u or sun4v system.
66 * For children of other nodes, it is bus type specific. So
67 * we walk up the tree until we discover a "device_type" property
68 * we recognize and we go from there.
70 static void __init sparc32_path_component(struct device_node *dp, char *tmp_buf)
72 struct linux_prom_registers *regs;
73 struct property *rprop;
75 rprop = of_find_property(dp, "reg", NULL);
80 sprintf(tmp_buf, "%s@%x,%x",
82 regs->which_io, regs->phys_addr);
85 /* "name@slot,offset" */
86 static void __init sbus_path_component(struct device_node *dp, char *tmp_buf)
88 struct linux_prom_registers *regs;
89 struct property *prop;
91 prop = of_find_property(dp, "reg", NULL);
96 sprintf(tmp_buf, "%s@%x,%x",
102 /* "name@devnum[,func]" */
103 static void __init pci_path_component(struct device_node *dp, char *tmp_buf)
105 struct linux_prom_pci_registers *regs;
106 struct property *prop;
109 prop = of_find_property(dp, "reg", NULL);
114 devfn = (regs->phys_hi >> 8) & 0xff;
116 sprintf(tmp_buf, "%s@%x,%x",
121 sprintf(tmp_buf, "%s@%x",
127 /* "name@addrhi,addrlo" */
128 static void __init ebus_path_component(struct device_node *dp, char *tmp_buf)
130 struct linux_prom_registers *regs;
131 struct property *prop;
133 prop = of_find_property(dp, "reg", NULL);
139 sprintf(tmp_buf, "%s@%x,%x",
141 regs->which_io, regs->phys_addr);
144 static void __init __build_path_component(struct device_node *dp, char *tmp_buf)
146 struct device_node *parent = dp->parent;
148 if (parent != NULL) {
149 if (!strcmp(parent->type, "pci") ||
150 !strcmp(parent->type, "pciex"))
151 return pci_path_component(dp, tmp_buf);
152 if (!strcmp(parent->type, "sbus"))
153 return sbus_path_component(dp, tmp_buf);
154 if (!strcmp(parent->type, "ebus"))
155 return ebus_path_component(dp, tmp_buf);
157 /* "isa" is handled with platform naming */
160 /* Use platform naming convention. */
161 return sparc32_path_component(dp, tmp_buf);
164 static char * __init build_path_component(struct device_node *dp)
166 char tmp_buf[64], *n;
169 __build_path_component(dp, tmp_buf);
170 if (tmp_buf[0] == '\0')
171 strcpy(tmp_buf, dp->name);
173 n = prom_early_alloc(strlen(tmp_buf) + 1);
179 static char * __init build_full_name(struct device_node *dp)
181 int len, ourlen, plen;
184 plen = strlen(dp->parent->full_name);
185 ourlen = strlen(dp->path_component_name);
186 len = ourlen + plen + 2;
188 n = prom_early_alloc(len);
189 strcpy(n, dp->parent->full_name);
190 if (!is_root_node(dp->parent)) {
191 strcpy(n + plen, "/");
194 strcpy(n + plen, dp->path_component_name);
199 static struct device_node * __init build_tree(struct device_node *parent, phandle node, struct device_node ***nextp)
201 struct device_node *dp;
203 dp = create_node(node, parent);
206 *nextp = &dp->allnext;
209 dp->path_component_name = build_path_component(dp);
210 dp->full_name = build_full_name(dp);
212 dp->child = build_tree(dp, prom_getchild(node), nextp);
214 dp->sibling = build_tree(parent, prom_getsibling(node), nextp);
220 struct device_node *of_console_device;
221 EXPORT_SYMBOL(of_console_device);
223 char *of_console_path;
224 EXPORT_SYMBOL(of_console_path);
226 char *of_console_options;
227 EXPORT_SYMBOL(of_console_options);
229 extern void restore_current(void);
231 static void __init of_console_init(void)
233 char *msg = "OF stdout device is: %s\n";
234 struct device_node *dp;
240 of_console_path = prom_early_alloc(256);
245 switch (*romvec->pv_stdout) {
259 prom_printf("Invalid PROM_V0 stdout value %u\n",
265 for_each_node_by_type(dp, type) {
270 prom_printf("Cannot find PROM_V0 console node.\n");
273 of_console_device = dp;
275 strcpy(of_console_path, dp->full_name);
276 if (!strcmp(type, "serial")) {
277 strcat(of_console_path,
278 (skip ? ":b" : ":a"));
285 fd = *romvec->pv_v2bootargs.fd_stdout;
287 spin_lock_irqsave(&prom_lock, flags);
288 node = (*romvec->pv_v2devops.v2_inst2pkg)(fd);
290 spin_unlock_irqrestore(&prom_lock, flags);
293 prom_printf("Cannot resolve stdout node from "
294 "instance %08x.\n", fd);
297 dp = of_find_node_by_phandle(node);
298 type = of_get_property(dp, "device_type", NULL);
301 prom_printf("Console stdout lacks "
302 "device_type property.\n");
306 if (strcmp(type, "display") && strcmp(type, "serial")) {
307 prom_printf("Console device_type is neither display "
312 of_console_device = dp;
314 if (prom_vers == PROM_V2) {
315 strcpy(of_console_path, dp->full_name);
316 switch (*romvec->pv_stdout) {
318 strcat(of_console_path, ":a");
321 strcat(of_console_path, ":b");
327 dp = of_find_node_by_path("/");
328 path = of_get_property(dp, "stdout-path", NULL);
330 prom_printf("No stdout-path in root node.\n");
333 strcpy(of_console_path, path);
338 of_console_options = strrchr(of_console_path, ':');
339 if (of_console_options) {
340 of_console_options++;
341 if (*of_console_options == '\0')
342 of_console_options = NULL;
345 prom_printf(msg, of_console_path);
346 printk(msg, of_console_path);
349 void __init prom_build_devicetree(void)
351 struct device_node **nextp;
353 allnodes = create_node(prom_root_node, NULL);
354 allnodes->path_component_name = "";
355 allnodes->full_name = "/";
357 nextp = &allnodes->allnext;
358 allnodes->child = build_tree(allnodes,
359 prom_getchild(allnodes->node),
363 printk("PROM: Built device tree with %u bytes of memory.\n",
364 prom_early_allocated);