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51#include "libfdt_env.h"
52
53#include <fdt.h>
54#include <libfdt.h>
55
56#include "libfdt_internal.h"
57
58int fdt_check_header(const void *fdt)
59{
60 if (fdt_magic(fdt) == FDT_MAGIC) {
61
62 if (fdt_version(fdt) < FDT_FIRST_SUPPORTED_VERSION)
63 return -FDT_ERR_BADVERSION;
64 if (fdt_last_comp_version(fdt) > FDT_LAST_SUPPORTED_VERSION)
65 return -FDT_ERR_BADVERSION;
66 } else if (fdt_magic(fdt) == FDT_SW_MAGIC) {
67
68 if (fdt_size_dt_struct(fdt) == 0)
69 return -FDT_ERR_BADSTATE;
70 } else {
71 return -FDT_ERR_BADMAGIC;
72 }
73
74 return 0;
75}
76
77const void *fdt_offset_ptr(const void *fdt, int offset, int len)
78{
79 const char *p;
80
81 if (fdt_version(fdt) >= 0x11)
82 if (((offset + len) < offset)
83 || ((offset + len) > fdt_size_dt_struct(fdt)))
84 return NULL;
85
86 p = _fdt_offset_ptr(fdt, offset);
87
88 if (p + len < p)
89 return NULL;
90 return p;
91}
92
93uint32_t fdt_next_tag(const void *fdt, int offset, int *nextoffset)
94{
95 const uint32_t *tagp, *lenp;
96 uint32_t tag;
97 const char *p;
98
99 if (offset % FDT_TAGSIZE)
100 return -1;
101
102 tagp = fdt_offset_ptr(fdt, offset, FDT_TAGSIZE);
103 if (! tagp)
104 return FDT_END;
105 tag = fdt32_to_cpu(*tagp);
106 offset += FDT_TAGSIZE;
107
108 switch (tag) {
109 case FDT_BEGIN_NODE:
110
111 do {
112 p = fdt_offset_ptr(fdt, offset++, 1);
113 } while (p && (*p != '\0'));
114 if (! p)
115 return FDT_END;
116 break;
117 case FDT_PROP:
118 lenp = fdt_offset_ptr(fdt, offset, sizeof(*lenp));
119 if (! lenp)
120 return FDT_END;
121
122 offset += 2*FDT_TAGSIZE + fdt32_to_cpu(*lenp);
123 break;
124 }
125
126 if (nextoffset)
127 *nextoffset = FDT_TAGALIGN(offset);
128
129 return tag;
130}
131
132int _fdt_check_node_offset(const void *fdt, int offset)
133{
134 if ((offset < 0) || (offset % FDT_TAGSIZE)
135 || (fdt_next_tag(fdt, offset, &offset) != FDT_BEGIN_NODE))
136 return -FDT_ERR_BADOFFSET;
137
138 return offset;
139}
140
141int fdt_next_node(const void *fdt, int offset, int *depth)
142{
143 int nextoffset = 0;
144 uint32_t tag;
145
146 if (offset >= 0)
147 if ((nextoffset = _fdt_check_node_offset(fdt, offset)) < 0)
148 return nextoffset;
149
150 do {
151 offset = nextoffset;
152 tag = fdt_next_tag(fdt, offset, &nextoffset);
153
154 switch (tag) {
155 case FDT_PROP:
156 case FDT_NOP:
157 break;
158
159 case FDT_BEGIN_NODE:
160 if (depth)
161 (*depth)++;
162 break;
163
164 case FDT_END_NODE:
165 if (depth)
166 (*depth)--;
167 break;
168
169 case FDT_END:
170 return -FDT_ERR_NOTFOUND;
171
172 default:
173 return -FDT_ERR_BADSTRUCTURE;
174 }
175 } while (tag != FDT_BEGIN_NODE);
176
177 return offset;
178}
179
180const char *_fdt_find_string(const char *strtab, int tabsize, const char *s)
181{
182 int len = strlen(s) + 1;
183 const char *last = strtab + tabsize - len;
184 const char *p;
185
186 for (p = strtab; p <= last; p++)
187 if (memcmp(p, s, len) == 0)
188 return p;
189 return NULL;
190}
191
192int fdt_move(const void *fdt, void *buf, int bufsize)
193{
194 FDT_CHECK_HEADER(fdt);
195
196 if (fdt_totalsize(fdt) > bufsize)
197 return -FDT_ERR_NOSPACE;
198
199 memmove(buf, fdt, fdt_totalsize(fdt));
200 return 0;
201}
202