releases/2.6.35.9/intel_idle-do-not-use-the-lapic-timer-for-atom-c2.patch

   1 From c25d29952b2a8c9aaf00e081c9162a0e383030cd Mon Sep 17 00:00:00 2001
   2 From: Len Brown <len.brown@intel.com>
   3 Date: Sat, 23 Oct 2010 23:25:53 -0400
   4 Subject: intel_idle: do not use the LAPIC timer for ATOM C2
   5
   6 From: Len Brown <len.brown@intel.com>
   7
   8 commit c25d29952b2a8c9aaf00e081c9162a0e383030cd upstream.
   9
  10 If we use the LAPIC timer during ATOM C2 on
  11 some nvidia chisets, the system stalls.
  12
  13 https://bugzilla.kernel.org/show_bug.cgi?id=21032
  14
  15 Signed-off-by: Len Brown <len.brown@intel.com>
  16 Cc: Tom Gundersen <teg@jklm.no>
  17 Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
  18
  19 ---
  20  drivers/idle/intel_idle.c |    2 +-
  21  1 file changed, 1 insertion(+), 1 deletion(-)
  22
  23 --- a/drivers/idle/intel_idle.c
  24 +++ b/drivers/idle/intel_idle.c
  25 @@ -308,7 +308,7 @@ static int intel_idle_probe(void)
  26                 break;
  27
  28         case 0x1C:      /* 28 - Atom Processor */
  29 -               lapic_timer_reliable_states = (1 << 2) | (1 << 1); /* C2, C1 */
  30 +               lapic_timer_reliable_states = (1 << 1); /* C1 */
  31                 cpuidle_state_table = atom_cstates;
  32                 choose_substate = choose_zero_substate;
  33                 break;