#include <errno.h> #include <stdio.h> #include <stdlib.h> #include <sys/mman.h> #include <unistd.h> #include <fcntl.h> static void *map_memory(const char *fn, unsigned base, unsigned size) { int fd; void *ptr; fd = open(fn, O_RDWR | O_SYNC); if(fd < 0) { perror("cannot open %s for mapping"); return MAP_FAILED; } ptr = mmap(0, size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, base); close(fd); if(ptr == MAP_FAILED) { fprintf(stderr,"cannot map %s (@%08x,%08x)\n", fn, base, size); } return ptr; } int main(int argc, char** argv) { void *grp_regs = map_memory("/dev/hw3d", 0, 1024 * 1024); printf("GPU base mapped at %p\n", grp_regs); int state_offset = 0x10140; printf("GPU state = %08lx\n", *((long*)((char*)grp_regs + state_offset)) ); return 0; }