1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * fdtdump.c - Contributed by Pantelis Antoniou <pantelis.antoniou AT gmail.com>
4  */
5 
6 #include <stdint.h>
7 #include <stdio.h>
8 #include <stdlib.h>
9 #include <string.h>
10 #include <ctype.h>
11 
12 #include <fdt.h>
13 #include <libfdt_env.h>
14 
15 #include "util.h"
16 
17 #define ALIGN(x, a)	(((x) + ((a) - 1)) & ~((a) - 1))
18 #define PALIGN(p, a)	((void *)(ALIGN((unsigned long)(p), (a))))
19 #define GET_CELL(p)	(p += 4, *((const uint32_t *)(p-4)))
20 
print_data(const char * data,int len)21 static void print_data(const char *data, int len)
22 {
23 	int i;
24 	const char *p = data;
25 
26 	/* no data, don't print */
27 	if (len == 0)
28 		return;
29 
30 	if (util_is_printable_string(data, len)) {
31 		printf(" = \"%s\"", (const char *)data);
32 	} else if ((len % 4) == 0) {
33 		printf(" = <");
34 		for (i = 0; i < len; i += 4)
35 			printf("0x%08x%s", fdt32_to_cpu(GET_CELL(p)),
36 			       i < (len - 4) ? " " : "");
37 		printf(">");
38 	} else {
39 		printf(" = [");
40 		for (i = 0; i < len; i++)
41 			printf("%02x%s", *p++, i < len - 1 ? " " : "");
42 		printf("]");
43 	}
44 }
45 
dump_blob(void * blob)46 static void dump_blob(void *blob)
47 {
48 	struct fdt_header *bph = blob;
49 	uint32_t off_mem_rsvmap = fdt32_to_cpu(bph->off_mem_rsvmap);
50 	uint32_t off_dt = fdt32_to_cpu(bph->off_dt_struct);
51 	uint32_t off_str = fdt32_to_cpu(bph->off_dt_strings);
52 	struct fdt_reserve_entry *p_rsvmap =
53 		(struct fdt_reserve_entry *)((char *)blob + off_mem_rsvmap);
54 	const char *p_struct = (const char *)blob + off_dt;
55 	const char *p_strings = (const char *)blob + off_str;
56 	uint32_t version = fdt32_to_cpu(bph->version);
57 	uint32_t totalsize = fdt32_to_cpu(bph->totalsize);
58 	uint32_t tag;
59 	const char *p, *s, *t;
60 	int depth, sz, shift;
61 	int i;
62 	uint64_t addr, size;
63 
64 	depth = 0;
65 	shift = 4;
66 
67 	printf("/dts-v1/;\n");
68 	printf("// magic:\t\t0x%x\n", fdt32_to_cpu(bph->magic));
69 	printf("// totalsize:\t\t0x%x (%d)\n", totalsize, totalsize);
70 	printf("// off_dt_struct:\t0x%x\n", off_dt);
71 	printf("// off_dt_strings:\t0x%x\n", off_str);
72 	printf("// off_mem_rsvmap:\t0x%x\n", off_mem_rsvmap);
73 	printf("// version:\t\t%d\n", version);
74 	printf("// last_comp_version:\t%d\n",
75 	       fdt32_to_cpu(bph->last_comp_version));
76 	if (version >= 2)
77 		printf("// boot_cpuid_phys:\t0x%x\n",
78 		       fdt32_to_cpu(bph->boot_cpuid_phys));
79 
80 	if (version >= 3)
81 		printf("// size_dt_strings:\t0x%x\n",
82 		       fdt32_to_cpu(bph->size_dt_strings));
83 	if (version >= 17)
84 		printf("// size_dt_struct:\t0x%x\n",
85 		       fdt32_to_cpu(bph->size_dt_struct));
86 	printf("\n");
87 
88 	for (i = 0; ; i++) {
89 		addr = fdt64_to_cpu(p_rsvmap[i].address);
90 		size = fdt64_to_cpu(p_rsvmap[i].size);
91 		if (addr == 0 && size == 0)
92 			break;
93 
94 		printf("/memreserve/ %llx %llx;\n",
95 		       (unsigned long long)addr, (unsigned long long)size);
96 	}
97 
98 	p = p_struct;
99 	while ((tag = fdt32_to_cpu(GET_CELL(p))) != FDT_END) {
100 
101 		/* printf("tag: 0x%08x (%d)\n", tag, p - p_struct); */
102 
103 		if (tag == FDT_BEGIN_NODE) {
104 			s = p;
105 			p = PALIGN(p + strlen(s) + 1, 4);
106 
107 			if (*s == '\0')
108 				s = "/";
109 
110 			printf("%*s%s {\n", depth * shift, "", s);
111 
112 			depth++;
113 			continue;
114 		}
115 
116 		if (tag == FDT_END_NODE) {
117 			depth--;
118 
119 			printf("%*s};\n", depth * shift, "");
120 			continue;
121 		}
122 
123 		if (tag == FDT_NOP) {
124 			printf("%*s// [NOP]\n", depth * shift, "");
125 			continue;
126 		}
127 
128 		if (tag != FDT_PROP) {
129 			fprintf(stderr, "%*s ** Unknown tag 0x%08x\n", depth * shift, "", tag);
130 			break;
131 		}
132 		sz = fdt32_to_cpu(GET_CELL(p));
133 		s = p_strings + fdt32_to_cpu(GET_CELL(p));
134 		if (version < 16 && sz >= 8)
135 			p = PALIGN(p, 8);
136 		t = p;
137 
138 		p = PALIGN(p + sz, 4);
139 
140 		printf("%*s%s", depth * shift, "", s);
141 		print_data(t, sz);
142 		printf(";\n");
143 	}
144 }
145 
146 
main(int argc,char * argv[])147 int main(int argc, char *argv[])
148 {
149 	char *buf;
150 
151 	if (argc < 2) {
152 		fprintf(stderr, "supply input filename\n");
153 		return 5;
154 	}
155 
156 	buf = utilfdt_read(argv[1]);
157 	if (buf)
158 		dump_blob(buf);
159 	else
160 		return 10;
161 
162 	return 0;
163 }
164