1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | /* pdt.c: OF PROM device tree support 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 | * Adapted for multiple architectures by Andres Salomon <dilinger@queued.net> |
12 | */ |
13 | |
14 | #include <linux/kernel.h> |
15 | #include <linux/module.h> |
16 | #include <linux/errno.h> |
17 | #include <linux/mutex.h> |
18 | #include <linux/slab.h> |
19 | #include <linux/of.h> |
20 | #include <linux/of_pdt.h> |
21 | |
22 | static struct of_pdt_ops *of_pdt_prom_ops __initdata; |
23 | |
24 | #if defined(CONFIG_SPARC) |
25 | unsigned int of_pdt_unique_id __initdata; |
26 | |
27 | #define of_pdt_incr_unique_id(p) do { \ |
28 | (p)->unique_id = of_pdt_unique_id++; \ |
29 | } while (0) |
30 | |
31 | static char * __init of_pdt_build_full_name(struct device_node *dp) |
32 | { |
33 | return build_path_component(dp); |
34 | } |
35 | |
36 | #else /* CONFIG_SPARC */ |
37 | |
38 | static inline void of_pdt_incr_unique_id(void *p) { } |
39 | static inline void irq_trans_init(struct device_node *dp) { } |
40 | |
41 | static char * __init of_pdt_build_full_name(struct device_node *dp) |
42 | { |
43 | static int failsafe_id = 0; /* for generating unique names on failure */ |
44 | const char *name; |
45 | char path[256]; |
46 | char *buf; |
47 | int len; |
48 | |
49 | if (!of_pdt_prom_ops->pkg2path(dp->phandle, path, sizeof(path), &len)) { |
50 | name = kbasename(path); |
51 | buf = prom_early_alloc(strlen(name) + 1); |
52 | strcpy(p: buf, q: name); |
53 | return buf; |
54 | } |
55 | |
56 | name = of_get_property(node: dp, name: "name" , lenp: &len); |
57 | buf = prom_early_alloc(size: len + 16); |
58 | sprintf(buf, fmt: "%s@unknown%i" , name, failsafe_id++); |
59 | pr_err("%s: pkg2path failed; assigning %s\n" , __func__, buf); |
60 | return buf; |
61 | } |
62 | |
63 | #endif /* !CONFIG_SPARC */ |
64 | |
65 | static struct property * __init of_pdt_build_one_prop(phandle node, char *prev, |
66 | char *special_name, |
67 | void *special_val, |
68 | int special_len) |
69 | { |
70 | static struct property *tmp = NULL; |
71 | struct property *p; |
72 | int err; |
73 | |
74 | if (tmp) { |
75 | p = tmp; |
76 | memset(p, 0, sizeof(*p) + 32); |
77 | tmp = NULL; |
78 | } else { |
79 | p = prom_early_alloc(size: sizeof(struct property) + 32); |
80 | of_pdt_incr_unique_id(p); |
81 | } |
82 | |
83 | p->name = (char *) (p + 1); |
84 | if (special_name) { |
85 | strcpy(p: p->name, q: special_name); |
86 | p->length = special_len; |
87 | p->value = prom_early_alloc(size: special_len); |
88 | memcpy(p->value, special_val, special_len); |
89 | } else { |
90 | err = of_pdt_prom_ops->nextprop(node, prev, p->name); |
91 | if (err) { |
92 | tmp = p; |
93 | return NULL; |
94 | } |
95 | p->length = of_pdt_prom_ops->getproplen(node, p->name); |
96 | if (p->length <= 0) { |
97 | p->length = 0; |
98 | } else { |
99 | int len; |
100 | |
101 | p->value = prom_early_alloc(size: p->length + 1); |
102 | len = of_pdt_prom_ops->getproperty(node, p->name, |
103 | p->value, p->length); |
104 | if (len <= 0) |
105 | p->length = 0; |
106 | ((unsigned char *)p->value)[p->length] = '\0'; |
107 | } |
108 | } |
109 | return p; |
110 | } |
111 | |
112 | static struct property * __init of_pdt_build_prop_list(phandle node) |
113 | { |
114 | struct property *head, *tail; |
115 | |
116 | head = tail = of_pdt_build_one_prop(node, NULL, |
117 | special_name: ".node" , special_val: &node, special_len: sizeof(node)); |
118 | |
119 | tail->next = of_pdt_build_one_prop(node, NULL, NULL, NULL, special_len: 0); |
120 | tail = tail->next; |
121 | while(tail) { |
122 | tail->next = of_pdt_build_one_prop(node, prev: tail->name, |
123 | NULL, NULL, special_len: 0); |
124 | tail = tail->next; |
125 | } |
126 | |
127 | return head; |
128 | } |
129 | |
130 | static char * __init of_pdt_get_one_property(phandle node, const char *name) |
131 | { |
132 | char *buf = "<NULL>" ; |
133 | int len; |
134 | |
135 | len = of_pdt_prom_ops->getproplen(node, name); |
136 | if (len > 0) { |
137 | buf = prom_early_alloc(size: len); |
138 | len = of_pdt_prom_ops->getproperty(node, name, buf, len); |
139 | } |
140 | |
141 | return buf; |
142 | } |
143 | |
144 | static struct device_node * __init of_pdt_create_node(phandle node, |
145 | struct device_node *parent) |
146 | { |
147 | struct device_node *dp; |
148 | |
149 | if (!node) |
150 | return NULL; |
151 | |
152 | dp = prom_early_alloc(size: sizeof(*dp)); |
153 | of_node_init(node: dp); |
154 | of_pdt_incr_unique_id(p: dp); |
155 | dp->parent = parent; |
156 | |
157 | dp->name = of_pdt_get_one_property(node, name: "name" ); |
158 | dp->phandle = node; |
159 | |
160 | dp->properties = of_pdt_build_prop_list(node); |
161 | |
162 | dp->full_name = of_pdt_build_full_name(dp); |
163 | |
164 | irq_trans_init(dp); |
165 | |
166 | return dp; |
167 | } |
168 | |
169 | static struct device_node * __init of_pdt_build_tree(struct device_node *parent, |
170 | phandle node) |
171 | { |
172 | struct device_node *ret = NULL, *prev_sibling = NULL; |
173 | struct device_node *dp; |
174 | |
175 | while (1) { |
176 | dp = of_pdt_create_node(node, parent); |
177 | if (!dp) |
178 | break; |
179 | |
180 | if (prev_sibling) |
181 | prev_sibling->sibling = dp; |
182 | |
183 | if (!ret) |
184 | ret = dp; |
185 | prev_sibling = dp; |
186 | |
187 | dp->child = of_pdt_build_tree(parent: dp, node: of_pdt_prom_ops->getchild(node)); |
188 | |
189 | node = of_pdt_prom_ops->getsibling(node); |
190 | } |
191 | |
192 | return ret; |
193 | } |
194 | |
195 | static void * __init kernel_tree_alloc(u64 size, u64 align) |
196 | { |
197 | return prom_early_alloc(size); |
198 | } |
199 | |
200 | void __init of_pdt_build_devicetree(phandle root_node, struct of_pdt_ops *ops) |
201 | { |
202 | BUG_ON(!ops); |
203 | of_pdt_prom_ops = ops; |
204 | |
205 | of_root = of_pdt_create_node(node: root_node, NULL); |
206 | of_root->full_name = "/" ; |
207 | |
208 | of_root->child = of_pdt_build_tree(parent: of_root, |
209 | node: of_pdt_prom_ops->getchild(of_root->phandle)); |
210 | |
211 | /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */ |
212 | of_alias_scan(dt_alloc: kernel_tree_alloc); |
213 | } |
214 | |