]>
git.ipfire.org Git - people/ms/u-boot.git/blob - tools/mkexynosspl.c
2 * Copyright (C) 2012 Samsung Electronics
4 * SPDX-License-Identifier: GPL-2.0+
16 #define CHECKSUM_OFFSET (14*1024-4)
17 #define FILE_PERM (S_IRUSR | S_IWUSR | S_IRGRP \
18 | S_IWGRP | S_IROTH | S_IWOTH)
20 * Requirement for the fixed size SPL header:
21 * IROM code reads first (CHECKSUM_OFFSET + 4) bytes from boot device. It then
22 * calculates the checksum of CHECKSUM_OFFSET bytes and compares with data at
23 * CHECKSUM_OFFSET location.
25 * Requirement for the variable size SPL header:
27 * IROM code reads the below header to find out the size of the blob (total
28 * size, header size included) and its checksum. Then it reads the rest of the
29 * blob [i.e size - sizeof(struct var_size_header) bytes], calculates the
30 * checksum and compares it with value read from the header.
32 struct var_size_header
{
34 uint32_t spl_checksum
;
38 static const char *prog_name
;
40 static void write_to_file(int ofd
, void *buffer
, int size
)
42 if (write(ofd
, buffer
, size
) == size
)
45 fprintf(stderr
, "%s: Failed to write to output file: %s\n",
46 prog_name
, strerror(errno
));
51 * The argv is expected to include one optional parameter and two filenames:
54 * --vs - turns on the variable size SPL mode
55 * IN - the u-boot SPL binary, usually u-boot-spl.bin
56 * OUT - the prepared SPL blob, usually ${BOARD}-spl.bin
58 * This utility first reads the "u-boot-spl.bin" into a buffer. In case of
59 * fixed size SPL the buffer size is exactly CHECKSUM_OFFSET (such that
60 * smaller u-boot-spl.bin gets padded with 0xff bytes, the larger than limit
61 * u-boot-spl.bin causes an error). For variable size SPL the buffer size is
62 * eqaul to size of the IN file.
64 * Then it calculates checksum of the buffer by just summing up all bytes.
67 * - for fixed size SPL the buffer is written into the output file and the
68 * checksum is appended to the file in little endian format, which results
69 * in checksum added exactly at CHECKSUM_OFFSET.
71 * - for variable size SPL the checksum and file size are stored in the
72 * var_size_header structure (again, in little endian format) and the
73 * structure is written into the output file. Then the buffer is written
74 * into the output file.
76 int main(int argc
, char **argv
)
78 unsigned char *buffer
;
80 uint32_t checksum
= 0;
82 int var_size_flag
, read_size
, count
;
84 const int if_index
= argc
- 2; /* Input file name index in argv. */
85 const int of_index
= argc
- 1; /* Output file name index in argv. */
87 /* Strip path off the program name. */
88 prog_name
= strrchr(argv
[0], '/');
96 ((argc
== 4) && strcmp(argv
[1], "--vs"))) {
97 fprintf(stderr
, "Usage: %s [--vs] <infile> <outfile>\n",
102 /* four args mean variable size SPL wrapper is required */
103 var_size_flag
= (argc
== 4);
105 ifd
= open(argv
[if_index
], O_RDONLY
);
107 fprintf(stderr
, "%s: Can't open %s: %s\n",
108 prog_name
, argv
[if_index
], strerror(errno
));
112 ofd
= open(argv
[of_index
], O_WRONLY
| O_CREAT
| O_TRUNC
, FILE_PERM
);
114 fprintf(stderr
, "%s: Can't open %s: %s\n",
115 prog_name
, argv
[of_index
], strerror(errno
));
119 if (fstat(ifd
, &stat
)) {
120 fprintf(stderr
, "%s: Unable to get size of %s: %s\n",
121 prog_name
, argv
[if_index
], strerror(errno
));
131 if (len
> CHECKSUM_OFFSET
) {
133 "%s: %s is too big (exceeds %d bytes)\n",
134 prog_name
, argv
[if_index
], CHECKSUM_OFFSET
);
137 count
= CHECKSUM_OFFSET
;
141 buffer
= malloc(count
);
144 "%s: Failed to allocate %d bytes to store %s\n",
145 prog_name
, count
, argv
[if_index
]);
149 if (read(ifd
, buffer
, read_size
) != read_size
) {
150 fprintf(stderr
, "%s: Can't read %s: %s\n",
151 prog_name
, argv
[if_index
], strerror(errno
));
155 /* Pad if needed with 0xff to make flashing faster. */
156 if (read_size
< count
)
157 memset((char *)buffer
+ read_size
, 0xff, count
- read_size
);
159 for (i
= 0, checksum
= 0; i
< count
; i
++)
160 checksum
+= buffer
[i
];
161 checksum
= cpu_to_le32(checksum
);
164 /* Prepare and write out the variable size SPL header. */
165 struct var_size_header vsh
;
168 memset(&vsh
, 0, sizeof(vsh
));
169 memcpy(&vsh
.spl_checksum
, &checksum
, sizeof(checksum
));
171 spl_size
= cpu_to_le32(count
+ sizeof(struct var_size_header
));
172 memcpy(&vsh
.spl_size
, &spl_size
, sizeof(spl_size
));
173 write_to_file(ofd
, &vsh
, sizeof(vsh
));
176 write_to_file(ofd
, buffer
, count
);
178 /* For fixed size SPL checksum is appended in the end. */
180 write_to_file(ofd
, &checksum
, sizeof(checksum
));