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6#include "libfdt_env.h"
7
8#ifndef USE_HOSTCC
9#include <fdt.h>
10#include <libfdt.h>
11#else
12#include "fdt_host.h"
13#endif
14
15#include "libfdt_internal.h"
16
17int fdt_check_header(const void *fdt)
18{
19 if (fdt_magic(fdt) == FDT_MAGIC) {
20
21 if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
22 return -FDT_ERR_BADVERSION;
23 if (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION)
24 return -FDT_ERR_BADVERSION;
25 } else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
26
27 if (fdt_size_dt_struct(fdt) == 0)
28 return -FDT_ERR_BADSTATE;
29 } else {
30 return -FDT_ERR_BADMAGIC;
31 }
32
33 return 0;
34}
35
36const void *fdt_offset_ptr(const void *fdt, int offset, unsigned int len)
37{
38 const char *p;
39
40 if (fdt_version(fdt) >= 0x11)
41 if (((offset + len) < offset)
42 || ((offset + len) > fdt_size_dt_struct(fdt)))
43 return NULL;
44
45 p = _fdt_offset_ptr(fdt, offset);
46
47 if (p + len < p)
48 return NULL;
49 return p;
50}
51
52uint32_t fdt_next_tag(const void *fdt, int startoffset, int *nextoffset)
53{
54 const fdt32_t *tagp, *lenp;
55 uint32_t tag;
56 int offset = startoffset;
57 const char *p;
58
59 *nextoffset = -FDT_ERR_TRUNCATED;
60 tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);
61 if (!tagp)
62 return FDT_END;
63 tag = fdt32_to_cpu(*tagp);
64 offset += FDT_TAGSIZE;
65
66 *nextoffset = -FDT_ERR_BADSTRUCTURE;
67 switch (tag) {
68 case FDT_BEGIN_NODE:
69
70 do {
71 p = fdt_offset_ptr(fdt, offset++, 1);
72 } while (p && (*p != '\0'));
73 if (!p)
74 return FDT_END;
75 break;
76
77 case FDT_PROP:
78 lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));
79 if (!lenp)
80 return FDT_END;
81
82 offset += sizeof(struct fdt_property) - FDT_TAGSIZE
83 + fdt32_to_cpu(*lenp);
84 break;
85
86 case FDT_END:
87 case FDT_END_NODE:
88 case FDT_NOP:
89 break;
90
91 default:
92 return FDT_END;
93 }
94
95 if (!fdt_offset_ptr(fdt, startoffset, offset - startoffset))
96 return FDT_END;
97
98 *nextoffset = FDT_TAGALIGN(offset);
99 return tag;
100}
101
102int _fdt_check_node_offset(const void *fdt, int offset)
103{
104 if ((offset < 0) || (offset % FDT_TAGSIZE)
105 || (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE))
106 return -FDT_ERR_BADOFFSET;
107
108 return offset;
109}
110
111int _fdt_check_prop_offset(const void *fdt, int offset)
112{
113 if ((offset < 0) || (offset % FDT_TAGSIZE)
114 || (fdt_next_tag(fdt, offset, &offset) != FDT_PROP))
115 return -FDT_ERR_BADOFFSET;
116
117 return offset;
118}
119
120int fdt_next_node(const void *fdt, int offset, int *depth)
121{
122 int nextoffset = 0;
123 uint32_t tag;
124
125 if (offset >= 0)
126 if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0)
127 return nextoffset;
128
129 do {
130 offset = nextoffset;
131 tag = fdt_next_tag(fdt, offset, &nextoffset);
132
133 switch (tag) {
134 case FDT_PROP:
135 case FDT_NOP:
136 break;
137
138 case FDT_BEGIN_NODE:
139 if (depth)
140 (*depth)++;
141 break;
142
143 case FDT_END_NODE:
144 if (depth && ((--(*depth)) < 0))
145 return nextoffset;
146 break;
147
148 case FDT_END:
149 if ((nextoffset >= 0)
150 || ((nextoffset == -FDT_ERR_TRUNCATED) && !depth))
151 return -FDT_ERR_NOTFOUND;
152 else
153 return nextoffset;
154 }
155 } while (tag != FDT_BEGIN_NODE);
156
157 return offset;
158}
159
160int fdt_first_subnode(const void *fdt, int offset)
161{
162 int depth = 0;
163
164 offset = fdt_next_node(fdt, offset, &depth);
165 if (offset < 0 || depth != 1)
166 return -FDT_ERR_NOTFOUND;
167
168 return offset;
169}
170
171int fdt_next_subnode(const void *fdt, int offset)
172{
173 int depth = 1;
174
175
176
177
178
179 do {
180 offset = fdt_next_node(fdt, offset, &depth);
181 if (offset < 0 || depth < 1)
182 return -FDT_ERR_NOTFOUND;
183 } while (depth > 1);
184
185 return offset;
186}
187
188const char *_fdt_find_string(const char *strtab, int tabsize, const char *s)
189{
190 int len = strlen(s) + 1;
191 const char *last = strtab + tabsize - len;
192 const char *p;
193
194 for (p = strtab; p <= last; p++)
195 if (memcmp(p, s, len) == 0)
196 return p;
197 return NULL;
198}
199
200int fdt_move(const void *fdt, void *buf, int bufsize)
201{
202 FDT_CHECK_HEADER(fdt);
203
204 if (fdt_totalsize(fdt) > bufsize)
205 return -FDT_ERR_NOSPACE;
206
207 memmove(buf, fdt, fdt_totalsize(fdt));
208 return 0;
209}
210