Commit 4342f4ac authored by Greg Ungerer's avatar Greg Ungerer Committed by Linus Torvalds

m68knommu: fix ColdFire timer off by 1

The coldfire timer runs from 0 to TRR included, then 0 again and so on.  It
counts thus actually TRR + 1 steps for 1 tick, not TRR.  Fix that.
Signed-off-by: default avatarPhilippe De Muyter <phdm@macqel.be>
Signed-off-by: default avatarGreg Ungerer <gerg@uclinux.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 4a0df2ef
...@@ -62,10 +62,13 @@ void coldfire_tick(void) ...@@ -62,10 +62,13 @@ void coldfire_tick(void)
/***************************************************************************/ /***************************************************************************/
static int ticks_per_intr;
void coldfire_timer_init(irq_handler_t handler) void coldfire_timer_init(irq_handler_t handler)
{ {
__raw_writew(MCFTIMER_TMR_DISABLE, TA(MCFTIMER_TMR)); __raw_writew(MCFTIMER_TMR_DISABLE, TA(MCFTIMER_TMR));
__raw_writetrr(((MCF_BUSCLK / 16) / HZ), TA(MCFTIMER_TRR)); ticks_per_intr = (MCF_BUSCLK / 16) / HZ;
__raw_writetrr(ticks_per_intr - 1, TA(MCFTIMER_TRR));
__raw_writew(MCFTIMER_TMR_ENORI | MCFTIMER_TMR_CLK16 | __raw_writew(MCFTIMER_TMR_ENORI | MCFTIMER_TMR_CLK16 |
MCFTIMER_TMR_RESTART | MCFTIMER_TMR_ENABLE, TA(MCFTIMER_TMR)); MCFTIMER_TMR_RESTART | MCFTIMER_TMR_ENABLE, TA(MCFTIMER_TMR));
...@@ -81,11 +84,10 @@ void coldfire_timer_init(irq_handler_t handler) ...@@ -81,11 +84,10 @@ void coldfire_timer_init(irq_handler_t handler)
unsigned long coldfire_timer_offset(void) unsigned long coldfire_timer_offset(void)
{ {
unsigned long trr, tcn, offset; unsigned long tcn, offset;
tcn = __raw_readw(TA(MCFTIMER_TCN)); tcn = __raw_readw(TA(MCFTIMER_TCN));
trr = __raw_readtrr(TA(MCFTIMER_TRR)); offset = ((tcn + 1) * (1000000 / HZ)) / ticks_per_intr;
offset = (tcn * (1000000 / HZ)) / trr;
/* Check if we just wrapped the counters and maybe missed a tick */ /* Check if we just wrapped the counters and maybe missed a tick */
if ((offset < (1000000 / HZ / 2)) && mcf_timerirqpending(1)) if ((offset < (1000000 / HZ / 2)) && mcf_timerirqpending(1))
......
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