xref: /openbmc/linux/arch/sparc/kernel/prom_common.c (revision 4f3db074)
1 /* prom_common.c: OF device tree support common code.
2  *
3  * Paul Mackerras	August 1996.
4  * Copyright (C) 1996-2005 Paul Mackerras.
5  *
6  *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
7  *    {engebret|bergner}@us.ibm.com
8  *
9  *  Adapted for sparc by David S. Miller davem@davemloft.net
10  *
11  *      This program is free software; you can redistribute it and/or
12  *      modify it under the terms of the GNU General Public License
13  *      as published by the Free Software Foundation; either version
14  *      2 of the License, or (at your option) any later version.
15  */
16 
17 #include <linux/kernel.h>
18 #include <linux/export.h>
19 #include <linux/errno.h>
20 #include <linux/mutex.h>
21 #include <linux/slab.h>
22 #include <linux/of.h>
23 #include <linux/of_pdt.h>
24 #include <asm/prom.h>
25 #include <asm/oplib.h>
26 
27 #include "prom.h"
28 
29 struct device_node *of_console_device;
30 EXPORT_SYMBOL(of_console_device);
31 
32 char *of_console_path;
33 EXPORT_SYMBOL(of_console_path);
34 
35 char *of_console_options;
36 EXPORT_SYMBOL(of_console_options);
37 
38 int of_getintprop_default(struct device_node *np, const char *name, int def)
39 {
40 	struct property *prop;
41 	int len;
42 
43 	prop = of_find_property(np, name, &len);
44 	if (!prop || len != 4)
45 		return def;
46 
47 	return *(int *) prop->value;
48 }
49 EXPORT_SYMBOL(of_getintprop_default);
50 
51 DEFINE_MUTEX(of_set_property_mutex);
52 EXPORT_SYMBOL(of_set_property_mutex);
53 
54 int of_set_property(struct device_node *dp, const char *name, void *val, int len)
55 {
56 	struct property **prevp;
57 	unsigned long flags;
58 	void *new_val;
59 	int err;
60 
61 	new_val = kmemdup(val, len, GFP_KERNEL);
62 	if (!new_val)
63 		return -ENOMEM;
64 
65 	err = -ENODEV;
66 
67 	mutex_lock(&of_set_property_mutex);
68 	raw_spin_lock_irqsave(&devtree_lock, flags);
69 	prevp = &dp->properties;
70 	while (*prevp) {
71 		struct property *prop = *prevp;
72 
73 		if (!strcasecmp(prop->name, name)) {
74 			void *old_val = prop->value;
75 			int ret;
76 
77 			ret = prom_setprop(dp->phandle, name, val, len);
78 
79 			err = -EINVAL;
80 			if (ret >= 0) {
81 				prop->value = new_val;
82 				prop->length = len;
83 
84 				if (OF_IS_DYNAMIC(prop))
85 					kfree(old_val);
86 
87 				OF_MARK_DYNAMIC(prop);
88 
89 				err = 0;
90 			}
91 			break;
92 		}
93 		prevp = &(*prevp)->next;
94 	}
95 	raw_spin_unlock_irqrestore(&devtree_lock, flags);
96 	mutex_unlock(&of_set_property_mutex);
97 
98 	/* XXX Upate procfs if necessary... */
99 
100 	return err;
101 }
102 EXPORT_SYMBOL(of_set_property);
103 
104 int of_find_in_proplist(const char *list, const char *match, int len)
105 {
106 	while (len > 0) {
107 		int l;
108 
109 		if (!strcmp(list, match))
110 			return 1;
111 		l = strlen(list) + 1;
112 		list += l;
113 		len -= l;
114 	}
115 	return 0;
116 }
117 EXPORT_SYMBOL(of_find_in_proplist);
118 
119 /*
120  * SPARC32 and SPARC64's prom_nextprop() do things differently
121  * here, despite sharing the same interface.  SPARC32 doesn't fill in 'buf',
122  * returning NULL on an error.  SPARC64 fills in 'buf', but sets it to an
123  * empty string upon error.
124  */
125 static int __init handle_nextprop_quirks(char *buf, const char *name)
126 {
127 	if (!name || strlen(name) == 0)
128 		return -1;
129 
130 #ifdef CONFIG_SPARC32
131 	strcpy(buf, name);
132 #endif
133 	return 0;
134 }
135 
136 static int __init prom_common_nextprop(phandle node, char *prev, char *buf)
137 {
138 	const char *name;
139 
140 	buf[0] = '\0';
141 	name = prom_nextprop(node, prev, buf);
142 	return handle_nextprop_quirks(buf, name);
143 }
144 
145 unsigned int prom_early_allocated __initdata;
146 
147 static struct of_pdt_ops prom_sparc_ops __initdata = {
148 	.nextprop = prom_common_nextprop,
149 	.getproplen = prom_getproplen,
150 	.getproperty = prom_getproperty,
151 	.getchild = prom_getchild,
152 	.getsibling = prom_getsibling,
153 };
154 
155 void __init prom_build_devicetree(void)
156 {
157 	of_pdt_build_devicetree(prom_root_node, &prom_sparc_ops);
158 	of_console_init();
159 
160 	pr_info("PROM: Built device tree with %u bytes of memory.\n",
161 			prom_early_allocated);
162 }
163