diff options
Diffstat (limited to 'arch/powerpc/boot/mktree.c')
-rw-r--r-- | arch/powerpc/boot/mktree.c | 152 |
1 files changed, 152 insertions, 0 deletions
diff --git a/arch/powerpc/boot/mktree.c b/arch/powerpc/boot/mktree.c new file mode 100644 index 00000000000..4cb89299365 --- /dev/null +++ b/arch/powerpc/boot/mktree.c @@ -0,0 +1,152 @@ +/* + * Makes a tree bootable image for IBM Evaluation boards. + * Basically, just take a zImage, skip the ELF header, and stuff + * a 32 byte header on the front. + * + * We use htonl, which is a network macro, to make sure we're doing + * The Right Thing on an LE machine. It's non-obvious, but it should + * work on anything BSD'ish. + */ + +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/stat.h> +#include <unistd.h> +#include <netinet/in.h> +#ifdef __sun__ +#include <inttypes.h> +#else +#include <stdint.h> +#endif + +/* This gets tacked on the front of the image. There are also a few + * bytes allocated after the _start label used by the boot rom (see + * head.S for details). + */ +typedef struct boot_block { + uint32_t bb_magic; /* 0x0052504F */ + uint32_t bb_dest; /* Target address of the image */ + uint32_t bb_num_512blocks; /* Size, rounded-up, in 512 byte blks */ + uint32_t bb_debug_flag; /* Run debugger or image after load */ + uint32_t bb_entry_point; /* The image address to start */ + uint32_t bb_checksum; /* 32 bit checksum including header */ + uint32_t reserved[2]; +} boot_block_t; + +#define IMGBLK 512 +char tmpbuf[IMGBLK]; + +int main(int argc, char *argv[]) +{ + int in_fd, out_fd; + int nblks, i; + uint cksum, *cp; + struct stat st; + boot_block_t bt; + + if (argc < 3) { + fprintf(stderr, "usage: %s <zImage-file> <boot-image> [entry-point]\n",argv[0]); + exit(1); + } + + if (stat(argv[1], &st) < 0) { + perror("stat"); + exit(2); + } + + nblks = (st.st_size + IMGBLK) / IMGBLK; + + bt.bb_magic = htonl(0x0052504F); + + /* If we have the optional entry point parameter, use it */ + if (argc == 4) + bt.bb_dest = bt.bb_entry_point = htonl(strtoul(argv[3], NULL, 0)); + else + bt.bb_dest = bt.bb_entry_point = htonl(0x500000); + + /* We know these from the linker command. + * ...and then move it up into memory a little more so the + * relocation can happen. + */ + bt.bb_num_512blocks = htonl(nblks); + bt.bb_debug_flag = 0; + + bt.bb_checksum = 0; + + /* To be neat and tidy :-). + */ + bt.reserved[0] = 0; + bt.reserved[1] = 0; + + if ((in_fd = open(argv[1], O_RDONLY)) < 0) { + perror("zImage open"); + exit(3); + } + + if ((out_fd = open(argv[2], (O_RDWR | O_CREAT | O_TRUNC), 0666)) < 0) { + perror("bootfile open"); + exit(3); + } + + cksum = 0; + cp = (void *)&bt; + for (i=0; i<sizeof(bt)/sizeof(uint); i++) + cksum += *cp++; + + /* Assume zImage is an ELF file, and skip the 64K header. + */ + if (read(in_fd, tmpbuf, IMGBLK) != IMGBLK) { + fprintf(stderr, "%s is too small to be an ELF image\n", + argv[1]); + exit(4); + } + + if ((*(uint *)tmpbuf) != htonl(0x7f454c46)) { + fprintf(stderr, "%s is not an ELF image\n", argv[1]); + exit(4); + } + + if (lseek(in_fd, (64 * 1024), SEEK_SET) < 0) { + fprintf(stderr, "%s failed to seek in ELF image\n", argv[1]); + exit(4); + } + + nblks -= (64 * 1024) / IMGBLK; + + /* And away we go...... + */ + if (write(out_fd, &bt, sizeof(bt)) != sizeof(bt)) { + perror("boot-image write"); + exit(5); + } + + while (nblks-- > 0) { + if (read(in_fd, tmpbuf, IMGBLK) < 0) { + perror("zImage read"); + exit(5); + } + cp = (uint *)tmpbuf; + for (i=0; i<sizeof(tmpbuf)/sizeof(uint); i++) + cksum += *cp++; + if (write(out_fd, tmpbuf, sizeof(tmpbuf)) != sizeof(tmpbuf)) { + perror("boot-image write"); + exit(5); + } + } + + /* rewrite the header with the computed checksum. + */ + bt.bb_checksum = htonl(cksum); + if (lseek(out_fd, 0, SEEK_SET) < 0) { + perror("rewrite seek"); + exit(1); + } + if (write(out_fd, &bt, sizeof(bt)) != sizeof(bt)) { + perror("boot-image rewrite"); + exit(1); + } + + exit(0); +} |