Merge tag 'drm-msm-fixes-2021-05-09' of https://gitlab.freedesktop.org/drm/msm into...
[linux-2.6-microblaze.git] / drivers / of / pdt.c
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(buf, name);
53                 return buf;
54         }
55
56         name = of_get_property(dp, "name", &len);
57         buf = prom_early_alloc(len + 16);
58         sprintf(buf, "%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(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->name, special_name);
86                 p->length = special_len;
87                 p->value = prom_early_alloc(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(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                                      ".node", &node, sizeof(node));
118
119         tail->next = of_pdt_build_one_prop(node, NULL, NULL, NULL, 0);
120         tail = tail->next;
121         while(tail) {
122                 tail->next = of_pdt_build_one_prop(node, tail->name,
123                                             NULL, NULL, 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(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(sizeof(*dp));
153         of_node_init(dp);
154         of_pdt_incr_unique_id(dp);
155         dp->parent = parent;
156
157         dp->name = of_pdt_get_one_property(node, "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(dp, 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(root_node, NULL);
206         of_root->full_name = "/";
207
208         of_root->child = of_pdt_build_tree(of_root,
209                                 of_pdt_prom_ops->getchild(of_root->phandle));
210
211         /* Get pointer to "/chosen" and "/aliases" nodes for use everywhere */
212         of_alias_scan(kernel_tree_alloc);
213 }