void
ramdisk_init(void)
{
int i;
char dev_name[] = "rd0";
dev_register(DEV_RAMDISK, &ramdisk_dev);
for (i = 1; i < RAM_DISKS; i++)
{
int len, vlen;
const char *parameter;
const char *value;
/* Considering RAM_DISKS < 10 for now. */
dev_name[2] = (i - 1) + 0x30;
parameter = bootparam_get_parameter(dev_name, &len);
if (!parameter)
continue;
value = bootparam_get_value("addr", &vlen,
parameter, len);
if (value)
ramdisk[i].phy_addr = strtoptr(value, NULL, 0);
value = bootparam_get_value("size", &vlen,
parameter, len);
if (value)
ramdisk[i].len = strtol(value, NULL, 0);
}
}
int main(int argc, char *argv[])
{
if(argc < 2) return usage();
int width = 4;
if(!strcmp(argv[1], "-b")) {
width = 1;
argc--;
argv++;
} else if(!strcmp(argv[1], "-s")) {
width = 2;
argc--;
argv++;
}
if(argc < 2) return usage();
uintptr_t addr = strtoptr(argv[1], 0, 16);
uintptr_t endaddr = 0;
char* end = strchr(argv[1], '-');
if (end)
endaddr = strtoptr(end + 1, 0, 16);
if (!endaddr)
endaddr = addr + width - 1;
if (endaddr <= addr) {
fprintf(stderr, "end address <= start address\n");
return -1;
}
bool set = false;
uint32_t value = 0;
if(argc > 2) {
set = true;
value = strtoul(argv[2], 0, 16);
}
int fd = open("/dev/mem", O_RDWR | O_SYNC);
if(fd < 0) {
fprintf(stderr,"cannot open /dev/mem\n");
return -1;
}
off64_t mmap_start = addr & ~(PAGE_SIZE - 1);
size_t mmap_size = endaddr - mmap_start + 1;
mmap_size = (mmap_size + PAGE_SIZE - 1) & ~(PAGE_SIZE - 1);
void* page = mmap64(0, mmap_size, PROT_READ | PROT_WRITE,
MAP_SHARED, fd, mmap_start);
if(page == MAP_FAILED){
fprintf(stderr,"cannot mmap region\n");
return -1;
}
while (addr <= endaddr) {
switch(width){
case 4: {
uint32_t* x = (uint32_t*) (((uintptr_t) page) + (addr & 4095));
if(set) *x = value;
fprintf(stderr,"%08"PRIxPTR": %08x\n", addr, *x);
break;
}
case 2: {
uint16_t* x = (uint16_t*) (((uintptr_t) page) + (addr & 4095));
if(set) *x = value;
fprintf(stderr,"%08"PRIxPTR": %04x\n", addr, *x);
break;
}
case 1: {
uint8_t* x = (uint8_t*) (((uintptr_t) page) + (addr & 4095));
if(set) *x = value;
fprintf(stderr,"%08"PRIxPTR": %02x\n", addr, *x);
break;
}
}
addr += width;
}
return 0;
}
