1// SPDX-License-Identifier: GPL-2.0-or-later
2/* prom_common.c: OF device tree support common code.
3 *
4 * Paul Mackerras	August 1996.
5 * Copyright (C) 1996-2005 Paul Mackerras.
6 *
7 *  Adapted for 64bit PowerPC by Dave Engebretsen and Peter Bergner.
8 *    {engebret|bergner}@us.ibm.com
9 *
10 *  Adapted for sparc by David S. Miller davem@davemloft.net
11 */
12
13#include <linux/kernel.h>
14#include <linux/export.h>
15#include <linux/errno.h>
16#include <linux/mutex.h>
17#include <linux/slab.h>
18#include <linux/of.h>
19#include <linux/of_pdt.h>
20#include <asm/prom.h>
21#include <asm/oplib.h>
22
23#include "prom.h"
24
25struct device_node *of_console_device;
26EXPORT_SYMBOL(of_console_device);
27
28char *of_console_path;
29EXPORT_SYMBOL(of_console_path);
30
31char *of_console_options;
32EXPORT_SYMBOL(of_console_options);
33
34int of_getintprop_default(struct device_node *np, const char *name, int def)
35{
36	struct property *prop;
37	int len;
38
39	prop = of_find_property(np, name, &len);
40	if (!prop || len != 4)
41		return def;
42
43	return *(int *) prop->value;
44}
45EXPORT_SYMBOL(of_getintprop_default);
46
47DEFINE_MUTEX(of_set_property_mutex);
48EXPORT_SYMBOL(of_set_property_mutex);
49
50int of_set_property(struct device_node *dp, const char *name, void *val, int len)
51{
52	struct property **prevp;
53	unsigned long flags;
54	void *new_val;
55	int err;
56
57	new_val = kmemdup(val, len, GFP_KERNEL);
58	if (!new_val)
59		return -ENOMEM;
60
61	err = -ENODEV;
62
63	mutex_lock(&of_set_property_mutex);
64	raw_spin_lock_irqsave(&devtree_lock, flags);
65	prevp = &dp->properties;
66	while (*prevp) {
67		struct property *prop = *prevp;
68
69		if (!strcasecmp(prop->name, name)) {
70			void *old_val = prop->value;
71			int ret;
72
73			ret = prom_setprop(dp->phandle, name, val, len);
74
75			err = -EINVAL;
76			if (ret >= 0) {
77				prop->value = new_val;
78				prop->length = len;
79
80				if (OF_IS_DYNAMIC(prop))
81					kfree(old_val);
82
83				OF_MARK_DYNAMIC(prop);
84
85				err = 0;
86			}
87			break;
88		}
89		prevp = &(*prevp)->next;
90	}
91	raw_spin_unlock_irqrestore(&devtree_lock, flags);
92	mutex_unlock(&of_set_property_mutex);
93
94	/* XXX Upate procfs if necessary... */
95
96	return err;
97}
98EXPORT_SYMBOL(of_set_property);
99
100int of_find_in_proplist(const char *list, const char *match, int len)
101{
102	while (len > 0) {
103		int l;
104
105		if (!strcmp(list, match))
106			return 1;
107		l = strlen(list) + 1;
108		list += l;
109		len -= l;
110	}
111	return 0;
112}
113EXPORT_SYMBOL(of_find_in_proplist);
114
115/*
116 * SPARC32 and SPARC64's prom_nextprop() do things differently
117 * here, despite sharing the same interface.  SPARC32 doesn't fill in 'buf',
118 * returning NULL on an error.  SPARC64 fills in 'buf', but sets it to an
119 * empty string upon error.
120 */
121static int __init handle_nextprop_quirks(char *buf, const char *name)
122{
123	if (!name || strlen(name) == 0)
124		return -1;
125
126#ifdef CONFIG_SPARC32
127	strcpy(buf, name);
128#endif
129	return 0;
130}
131
132static int __init prom_common_nextprop(phandle node, char *prev, char *buf)
133{
134	const char *name;
135
136	buf[0] = '\0';
137	name = prom_nextprop(node, prev, buf);
138	return handle_nextprop_quirks(buf, name);
139}
140
141unsigned int prom_early_allocated __initdata;
142
143static struct of_pdt_ops prom_sparc_ops __initdata = {
144	.nextprop = prom_common_nextprop,
145	.getproplen = prom_getproplen,
146	.getproperty = prom_getproperty,
147	.getchild = prom_getchild,
148	.getsibling = prom_getsibling,
149};
150
151void __init prom_build_devicetree(void)
152{
153	of_pdt_build_devicetree(prom_root_node, &prom_sparc_ops);
154	of_console_init();
155
156	pr_info("PROM: Built device tree with %u bytes of memory.\n",
157			prom_early_allocated);
158}
159