/*
** mmio_rd <phys_addr> <number-of-unsigned-longs>
**
** eg mmio_rd fed01500 1
*/
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

#include <sys/mman.h>

int main(int argc, char **argv)
{
	int fd = open("/dev/mem", O_RDONLY | O_SYNC);
	unsigned long phys_addr, len;	/* arg1, arg2 */
	unsigned long i, page_addr, page_size = getpagesize();
	volatile unsigned long *mem;

	if (fd < 0)
		perror("open /dev/mem");

	if (argc < 3)
		exit(-2);

	phys_addr = strtoul(argv[1], NULL, 16);
	phys_addr &= ~(sizeof(mem[0]) - 1);

	len = strtoul(argv[2], NULL, 16);

	/* KISS, can only dump one page at a time */
	if (len < 0 || (len > page_size / sizeof(mem[0])))
		exit(-22);

	page_addr = phys_addr & ~(page_size - 1);
	i = (phys_addr - page_addr) / sizeof(mem[0]);

	mem = mmap(NULL, page_size, PROT_READ, MAP_SHARED, fd, page_addr);
	if (mem == MAP_FAILED) {
		perror("mmap()");
		exit(-1);
	}

	for (; len && (i < (page_size / sizeof(mem[0]))); i++, len--) {
/*  printf("%016lx: ", page_addr + i*sizeof(mem[0])); */
		printf("0x%016lx\n", mem[i]);
	}

	return 0;
}