summaryrefslogtreecommitdiffstats
path: root/tools/socfpgaimage.c
blob: 8fe91fe80ee9ac9ab5c2c0f7af25705f212bd486 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
/*
 * Copyright (C) 2014 Charles Manning <cdhmanning@gmail.com>
 *
 * SPDX-License-Identifier:	GPL-2.0+
 *
 * Reference doc http://www.altera.com.cn/literature/hb/cyclone-v/cv_5400A.pdf
 * Note this doc is not entirely accurate. Of particular interest to us is the
 * "header" length field being in U32s and not bytes.
 *
 * "Header" is a structure of the following format.
 * this is positioned at 0x40.
 *
 * Endian is LSB.
 *
 * Offset   Length   Usage
 * -----------------------
 *   0x40        4   Validation word 0x31305341
 *   0x44        1   Version (whatever, zero is fine)
 *   0x45        1   Flags   (unused, zero is fine)
 *   0x46        2   Length  (in units of u32, including the end checksum).
 *   0x48        2   Zero
 *   0x4A        2   Checksum over the header. NB Not CRC32
 *
 * At the end of the code we have a 32-bit CRC checksum over whole binary
 * excluding the CRC.
 *
 * Note that the CRC used here is **not** the zlib/Adler crc32. It is the
 * CRC-32 used in bzip2, ethernet and elsewhere.
 *
 * The image is padded out to 64k, because that is what is
 * typically used to write the image to the boot medium.
 */

#include "pbl_crc32.h"
#include "imagetool.h"
#include "mkimage.h"

#include <image.h>

#define HEADER_OFFSET	0x40
#define VALIDATION_WORD	0x31305341
#define PADDED_SIZE	0x10000

/* To allow for adding CRC, the max input size is a bit smaller. */
#define MAX_INPUT_SIZE	(PADDED_SIZE - sizeof(uint32_t))

static uint8_t buffer[PADDED_SIZE];

static struct socfpga_header {
	uint32_t validation;
	uint8_t  version;
	uint8_t  flags;
	uint16_t length_u32;
	uint16_t zero;
	uint16_t checksum;
} header;

/*
 * The header checksum is just a very simple checksum over
 * the header area.
 * There is still a crc32 over the whole lot.
 */
static uint16_t hdr_checksum(struct socfpga_header *header)
{
	int len = sizeof(*header) - sizeof(header->checksum);
	uint8_t *buf = (uint8_t *)header;
	uint16_t ret = 0;

	while (--len)
		ret += *buf++;

	return ret;
}


static void build_header(uint8_t *buf, uint8_t version, uint8_t flags,
			 uint16_t length_bytes)
{
	header.validation = cpu_to_le32(VALIDATION_WORD);
	header.version = version;
	header.flags = flags;
	header.length_u32 = cpu_to_le16(length_bytes/4);
	header.zero = 0;
	header.checksum = cpu_to_le16(hdr_checksum(&header));

	memcpy(buf, &header, sizeof(header));
}

/*
 * Perform a rudimentary verification of header and return
 * size of image.
 */
static int verify_header(const uint8_t *buf)
{
	memcpy(&header, buf, sizeof(header));

	if (le32_to_cpu(header.validation) != VALIDATION_WORD)
		return -1;
	if (le16_to_cpu(header.checksum) != hdr_checksum(&header))
		return -1;

	return le16_to_cpu(header.length_u32) * 4;
}

/* Sign the buffer and return the signed buffer size */
static int sign_buffer(uint8_t *buf,
			uint8_t version, uint8_t flags,
			int len, int pad_64k)
{
	uint32_t calc_crc;

	/* Align the length up */
	len = (len + 3) & (~3);

	/* Build header, adding 4 bytes to length to hold the CRC32. */
	build_header(buf + HEADER_OFFSET,  version, flags, len + 4);

	/* Calculate and apply the CRC */
	calc_crc = ~pbl_crc32(0, (char *)buf, len);

	*((uint32_t *)(buf + len)) = cpu_to_le32(calc_crc);

	if (!pad_64k)
		return len + 4;

	return PADDED_SIZE;
}

/* Verify that the buffer looks sane */
static int verify_buffer(const uint8_t *buf)
{
	int len; /* Including 32bit CRC */
	uint32_t calc_crc;
	uint32_t buf_crc;

	len = verify_header(buf + HEADER_OFFSET);
	if (len < 0) {
		debug("Invalid header\n");
		return -1;
	}

	if (len < HEADER_OFFSET || len > PADDED_SIZE) {
		debug("Invalid header length (%i)\n", len);
		return -1;
	}

	/*
	 * Adjust length to the base of the CRC.
	 * Check the CRC.
	*/
	len -= 4;

	calc_crc = ~pbl_crc32(0, (const char *)buf, len);

	buf_crc = le32_to_cpu(*((uint32_t *)(buf + len)));

	if (buf_crc != calc_crc) {
		fprintf(stderr, "CRC32 does not match (%08x != %08x)\n",
			buf_crc, calc_crc);
		return -1;
	}

	return 0;
}

/* mkimage glue functions */
static int socfpgaimage_verify_header(unsigned char *ptr, int image_size,
			struct image_tool_params *params)
{
	if (image_size != PADDED_SIZE)
		return -1;

	return verify_buffer(ptr);
}

static void socfpgaimage_print_header(const void *ptr)
{
	if (verify_buffer(ptr) == 0)
		printf("Looks like a sane SOCFPGA preloader\n");
	else
		printf("Not a sane SOCFPGA preloader\n");
}

static int socfpgaimage_check_params(struct image_tool_params *params)
{
	/* Not sure if we should be accepting fflags */
	return	(params->dflag && (params->fflag || params->lflag)) ||
		(params->fflag && (params->dflag || params->lflag)) ||
		(params->lflag && (params->dflag || params->fflag));
}

static int socfpgaimage_check_image_types(uint8_t type)
{
	if (type == IH_TYPE_SOCFPGAIMAGE)
		return EXIT_SUCCESS;
	return EXIT_FAILURE;
}

/*
 * To work in with the mkimage framework, we do some ugly stuff...
 *
 * First, socfpgaimage_vrec_header() is called.
 * We prepend a fake header big enough to make the file PADDED_SIZE.
 * This gives us enough space to do what we want later.
 *
 * Next, socfpgaimage_set_header() is called.
 * We fix up the buffer by moving the image to the start of the buffer.
 * We now have some room to do what we need (add CRC and padding).
 */

static int data_size;
#define FAKE_HEADER_SIZE (PADDED_SIZE - data_size)

static int socfpgaimage_vrec_header(struct image_tool_params *params,
				struct image_type_params *tparams)
{
	struct stat sbuf;

	if (params->datafile &&
	    stat(params->datafile, &sbuf) == 0 &&
	    sbuf.st_size <= MAX_INPUT_SIZE) {
		data_size = sbuf.st_size;
		tparams->header_size = FAKE_HEADER_SIZE;
	}
	return 0;
}

static void socfpgaimage_set_header(void *ptr, struct stat *sbuf, int ifd,
				struct image_tool_params *params)
{
	uint8_t *buf = (uint8_t *)ptr;

	/*
	 * This function is called after vrec_header() has been called.
	 * At this stage we have the FAKE_HEADER_SIZE dummy bytes followed by
	 * data_size image bytes. Total = PADDED_SIZE.
	 * We need to fix the buffer by moving the image bytes back to
	 * the beginning of the buffer, then actually do the signing stuff...
	 */
	memmove(buf, buf + FAKE_HEADER_SIZE, data_size);
	memset(buf + data_size, 0, FAKE_HEADER_SIZE);

	sign_buffer(buf, 0, 0, data_size, 0);
}

U_BOOT_IMAGE_TYPE(
	socfpgaimage,
	"Altera SOCFPGA preloader support",
	0, /* This will be modified by vrec_header() */
	(void *)buffer,
	socfpgaimage_check_params,
	socfpgaimage_verify_header,
	socfpgaimage_print_header,
	socfpgaimage_set_header,
	NULL,
	socfpgaimage_check_image_types,
	NULL,
	socfpgaimage_vrec_header
);
OpenPOWER on IntegriCloud