Fix a race between clock_intr() and tick_ticker() when updating

'counter_upper' and 'counter_lower_last'. The race exists because
interrupts are enabled even though tick_ticker() executes in a
critical section.

Fix a bug in clock_intr() in how it updates the cached values of
'counter_upper' and 'counter_lower_last'. They are updated only
when the COUNT register rolls over. More interestingly it will *never*
update the cached values if 'counter_lower_last' happens to be zero.

Get rid of superfluous critical section in clock_intr(). There is no
reason to do this because clock_intr() executes in hard interrupt
context.

Switch back to using 'tick_ticker()' as the cpu ticker for Sibyte.

Reviewed by:	jmallett, mav

1 files changed, 0 insertions, 2 deletions

diff --git a/sys/mips/sibyte/sb_machdep.c b/sys/mips/sibyte/sb_machdep.c
index e8fcaa51f094..9e83426f6396 100644
--- a/sys/mips/sibyte/sb_machdep.c
+++ b/sys/mips/sibyte/sb_machdep.c
@@ -454,6 +454,4 @@ platform_start(__register_t a0, __register_t a1, __register_t a2,
 	mips_init();
 
 	mips_timer_init_params(sb_cpu_speed(), 0);
-
-	set_cputicker(sb_zbbus_cycle_count, sb_cpu_speed() / 2, 1);
 }