linux/arch/powerpc/boot/mktree.c
David Gibson f6dfc80554 [POWERPC] Support for the Ebony 440GP reference board in arch/powerpc
This adds platform support code for the Ebony (440GP) evaluation
board.  This includes both code in arch/powerpc/platforms/44x for
board initialization, and zImage wrapper code to correctly tweak the
flattened device tree based on information from the firmware.  The
zImage supports both IBM OpenBIOS (aka "treeboot") and old versions of
uboot which don't support a flattened device tree.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2007-05-08 14:47:32 +10:00

150 lines
3.4 KiB
C

/*
* 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 < 5) {
fprintf(stderr, "usage: %s <zImage-file> <boot-image> <load address> <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 */
bt.bb_dest = htonl(strtoul(argv[3], NULL, 0));
bt.bb_entry_point = htonl(strtoul(argv[4], NULL, 0));
/* 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);
}