xref: /freebsd/usr.bin/dtc/dtb.cc (revision 809a8352dd5bb83dca991ff6c82e509208afad26)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2013 David Chisnall
5  * All rights reserved.
6  *
7  * This software was developed by SRI International and the University of
8  * Cambridge Computer Laboratory under DARPA/AFRL contract (FA8750-10-C-0237)
9  * ("CTSRD"), as part of the DARPA CRASH research programme.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  *
32  * $FreeBSD$
33  */
34 
35 #include "dtb.hh"
36 #include <sys/types.h>
37 #include <inttypes.h>
38 #include <stdio.h>
39 #include <unistd.h>
40 
41 using std::string;
42 
43 namespace dtc
44 {
45 namespace dtb
46 {
47 
48 void output_writer::write_data(byte_buffer b)
49 {
50 	for (auto i : b)
51 	{
52 		write_data(i);
53 	}
54 }
55 
56 void
57 binary_writer::write_string(const string &name)
58 {
59 	push_string(buffer, name);
60 	// Trailing nul
61 	buffer.push_back(0);
62 }
63 
64 void
65 binary_writer::write_data(uint8_t v)
66 {
67 	buffer.push_back(v);
68 }
69 
70 void
71 binary_writer::write_data(uint32_t v)
72 {
73 	while (buffer.size() % 4 != 0)
74 	{
75 		buffer.push_back(0);
76 	}
77 	push_big_endian(buffer, v);
78 }
79 
80 void
81 binary_writer::write_data(uint64_t v)
82 {
83 	while (buffer.size() % 8 != 0)
84 	{
85 		buffer.push_back(0);
86 	}
87 	push_big_endian(buffer, v);
88 }
89 
90 void
91 binary_writer::write_to_file(int fd)
92 {
93 	// FIXME: Check return
94 	write(fd, buffer.data(), buffer.size());
95 }
96 
97 uint32_t
98 binary_writer::size()
99 {
100 	return buffer.size();
101 }
102 
103 void
104 asm_writer::write_line(const char *c)
105 {
106 	if (byte_count != 0)
107 	{
108 		byte_count = 0;
109 		buffer.push_back('\n');
110 	}
111 	write_string(c);
112 }
113 
114 void
115 asm_writer::write_byte(uint8_t b)
116 {
117 	char out[3] = {0};
118 	if (byte_count++ == 0)
119 	{
120 		buffer.push_back('\t');
121 	}
122 	write_string(".byte 0x");
123 	snprintf(out, 3, "%.2hhx", b);
124 	buffer.push_back(out[0]);
125 	buffer.push_back(out[1]);
126 	if (byte_count == 4)
127 	{
128 		buffer.push_back('\n');
129 		byte_count = 0;
130 	}
131 	else
132 	{
133 		buffer.push_back(';');
134 		buffer.push_back(' ');
135 	}
136 }
137 
138 void
139 asm_writer::write_label(const string &name)
140 {
141 	write_line("\t.globl ");
142 	push_string(buffer, name);
143 	buffer.push_back('\n');
144 	push_string(buffer, name);
145 	buffer.push_back(':');
146 	buffer.push_back('\n');
147 	buffer.push_back('_');
148 	push_string(buffer, name);
149 	buffer.push_back(':');
150 	buffer.push_back('\n');
151 
152 }
153 
154 void
155 asm_writer::write_comment(const string &name)
156 {
157 	write_line("\t/* ");
158 	push_string(buffer, name);
159 	write_string(" */\n");
160 }
161 
162 void
163 asm_writer::write_string(const char *c)
164 {
165 	while (*c)
166 	{
167 		buffer.push_back((uint8_t)*(c++));
168 	}
169 }
170 
171 
172 void
173 asm_writer::write_string(const string &name)
174 {
175 	write_line("\t.string \"");
176 	push_string(buffer, name);
177 	write_line("\"\n");
178 	bytes_written += name.size() + 1;
179 }
180 
181 void
182 asm_writer::write_data(uint8_t v)
183 {
184 	write_byte(v);
185 	bytes_written++;
186 }
187 
188 void
189 asm_writer::write_data(uint32_t v)
190 {
191 	if (bytes_written % 4 != 0)
192 	{
193 		write_line("\t.balign 4\n");
194 		bytes_written += (4 - (bytes_written % 4));
195 	}
196 	write_byte((v >> 24) & 0xff);
197 	write_byte((v >> 16) & 0xff);
198 	write_byte((v >> 8) & 0xff);
199 	write_byte((v >> 0) & 0xff);
200 	bytes_written += 4;
201 }
202 
203 void
204 asm_writer::write_data(uint64_t v)
205 {
206 	if (bytes_written % 8 != 0)
207 	{
208 		write_line("\t.balign 8\n");
209 		bytes_written += (8 - (bytes_written % 8));
210 	}
211 	write_byte((v >> 56) & 0xff);
212 	write_byte((v >> 48) & 0xff);
213 	write_byte((v >> 40) & 0xff);
214 	write_byte((v >> 32) & 0xff);
215 	write_byte((v >> 24) & 0xff);
216 	write_byte((v >> 16) & 0xff);
217 	write_byte((v >> 8) & 0xff);
218 	write_byte((v >> 0) & 0xff);
219 	bytes_written += 8;
220 }
221 
222 void
223 asm_writer::write_to_file(int fd)
224 {
225 	// FIXME: Check return
226 	write(fd, buffer.data(), buffer.size());
227 }
228 
229 uint32_t
230 asm_writer::size()
231 {
232 	return bytes_written;
233 }
234 
235 void
236 header::write(output_writer &out)
237 {
238 	out.write_label("dt_blob_start");
239 	out.write_label("dt_header");
240 	out.write_comment("magic");
241 	out.write_data(magic);
242 	out.write_comment("totalsize");
243 	out.write_data(totalsize);
244 	out.write_comment("off_dt_struct");
245 	out.write_data(off_dt_struct);
246 	out.write_comment("off_dt_strings");
247 	out.write_data(off_dt_strings);
248 	out.write_comment("off_mem_rsvmap");
249 	out.write_data(off_mem_rsvmap);
250 	out.write_comment("version");
251 	out.write_data(version);
252 	out.write_comment("last_comp_version");
253 	out.write_data(last_comp_version);
254 	out.write_comment("boot_cpuid_phys");
255 	out.write_data(boot_cpuid_phys);
256 	out.write_comment("size_dt_strings");
257 	out.write_data(size_dt_strings);
258 	out.write_comment("size_dt_struct");
259 	out.write_data(size_dt_struct);
260 }
261 
262 bool
263 header::read_dtb(input_buffer &input)
264 {
265 	if (!input.consume_binary(magic))
266 	{
267 		fprintf(stderr, "Missing magic token in header.");
268 		return false;
269 	}
270 	if (magic != 0xd00dfeed)
271 	{
272 		fprintf(stderr, "Bad magic token in header.  Got %" PRIx32
273 		                " expected 0xd00dfeed\n", magic);
274 		return false;
275 	}
276 	return input.consume_binary(totalsize) &&
277 	       input.consume_binary(off_dt_struct) &&
278 	       input.consume_binary(off_dt_strings) &&
279 	       input.consume_binary(off_mem_rsvmap) &&
280 	       input.consume_binary(version) &&
281 	       input.consume_binary(last_comp_version) &&
282 	       input.consume_binary(boot_cpuid_phys) &&
283 	       input.consume_binary(size_dt_strings) &&
284 	       input.consume_binary(size_dt_struct);
285 }
286 uint32_t
287 string_table::add_string(const string &str)
288 {
289 	auto old = string_offsets.find(str);
290 	if (old == string_offsets.end())
291 	{
292 		uint32_t start = size;
293 		// Don't forget the trailing nul
294 		size += str.size() + 1;
295 		string_offsets.insert(std::make_pair(str, start));
296 		strings.push_back(str);
297 		return start;
298 	}
299 	else
300 	{
301 		return old->second;
302 	}
303 }
304 
305 void
306 string_table::write(dtb::output_writer &writer)
307 {
308 	writer.write_comment("Strings table.");
309 	writer.write_label("dt_strings_start");
310 	for (auto &i : strings)
311 	{
312 		writer.write_string(i);
313 	}
314 	writer.write_label("dt_strings_end");
315 }
316 
317 } // namespace dtb
318 
319 } // namespace dtc
320 
321