ref: 168077885110cb40635ffe6afe5ecab2e4000a87
dir: /sys/src/boot/zynq/boothead.c/
#include <u.h> #include <libc.h> char *data; uchar head[0x8c0]; void usage(void) { fprint(2, "usage: %s file\n", argv0); exits("usage"); } void u32(int n, u32int p) { head[n] = p; head[n+1] = p >> 8; head[n+2] = p >> 16; head[n+3] = p >> 24; } u32int gu32(int n) { return head[n] | head[n+1] << 8 | head[n+2] << 16 | head[n+3] << 24; } void main(int argc, char **argv) { int fd, sz, i; u32int ck; ARGBEGIN { default: usage(); } ARGEND; if(argc != 1) usage(); fd = open(argv[0], OREAD); if(fd < 0) sysfatal("open: %r"); sz = seek(fd, 0, 2); if(sz < 0) sysfatal("seek: %r"); data = malloc(sz); if(data == nil) sysfatal("malloc: %r"); seek(fd, 0, 0); if(readn(fd, data, sz) < sz) sysfatal("read: %r"); close(fd); memset(head, 0, sizeof(head)); u32(0x20, 0xaa995566); u32(0x24, 0x584C4E58); u32(0x30, sizeof(head)); u32(0x34, sz); u32(0x40, sz); ck = 0; for(i = 0x20; i < 0x48; i += 4) ck += gu32(i); u32(0x48, ~ck); u32(0xa0, -1); write(1, head, sizeof(head)); write(1, data, sz); exits(nil); }