[coreboot - Bug #141] GRUB payload hangs in HP Elitebooks

[Riku Viitanen]

Issue #141 has been updated by Riku Viitanen.

Patch has now been merged to GRUB upstream.
https://git.savannah.gnu.org/cgit/grub.git/commit/?id=830456a6e3b6ac92d10f92...

----------------------------------------
Bug #141: GRUB payload hangs in HP Elitebooks
https://ticket.coreboot.org/issues/141#change-1531

* Author: Iru Cai
* Status: New
* Priority: Normal
* Assignee: Iru Cai
* Start date: 2017-09-19
----------------------------------------
There may be some problem when initializing the keyboard controller, but SeaBIOS payload works fine. Using GRUB payload directly or chainload GRUB payload with SeaBIOS will both hang the system.

I modified GRUB and find it hangs in set_scancodes(void), when calling the first write_mode. After ``grub_outb (mode, KEYBOARD_REG_DATA);``, the ``keyboard_controller_wait_until_ready()`` function goes to an infinite loop.

~~~
write_mode (int mode)
{
  unsigned i;
  for (i = 0; i < GRUB_AT_TRIES; i++)
    {
      grub_uint8_t ack;
      keyboard_controller_wait_until_ready ();
      grub_outb (0xf0, KEYBOARD_REG_DATA);
      keyboard_controller_wait_until_ready ();
      grub_outb (mode, KEYBOARD_REG_DATA);
      keyboard_controller_wait_until_ready ();
      ack = wait_ack ();
      if (ack == GRUB_AT_NACK)
        continue;
      if (ack == GRUB_AT_ACK)
        break;
      return 0;
    }

return (i != GRUB_AT_TRIES);
}
~~~

---Files--------------------------------
seabios.log (31.5 KB)
0005-at-keyboard-timeout.patch (1.09 KB)