Using redboot with x/y modem

Scott,

I tried a simple experiment to see if my hunch about interrupts was right. I have edited the code in command/cmd_mem.c to change the function do_mem_cp(). What I have done is disable the interrupts just before the cp command copies the data. I have left the interrupts disabled:

int do_mem_cp ( cmd_tbl_t *cmdtp, int flag, int argc, char *argv)
{
  ..
  ..
  // MJS: try disabling interrupts
  disable_interrupts();
  while (count-- > 0) {
    if (size == 4)
      *((ulong  *)dest) = *((ulong  *)addr);
    else if (size == 2)
      *((ushort *)dest) = *((ushort *)addr);
    else
      *((u_char *)dest) = *((u_char *)addr);
    addr += size;
    dest += size;
  }
  return 0;
}

I then typed these commands into u-boot:

cp 0x00050000 0x02000020 0x40000

go 0x02000154

and was very surprised to find that it now works perfectly!

If I remove the line which disables the interrupts then u-boot crashes and resets after I send the cp command. What does u-boot use interrupts for anyway? Timers for the timeouts perhaps? I am sure my quick and dirty fix here will have some serious side-effects somewhere else!

Mike