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: Philippe De Muyter <[EMAIL PROTECTED]> Signed-off-by: Greg Ungerer <[EMAIL PROTECTED]> --- diff -Naur linux-2.6.21/arch/m68knommu/platform/5307/timers.c linux-2.6.21-uc0/arch/m68knommu/platform/5307/timers.c --- linux-2.6.21/arch/m68knommu/platform/5307/timers.c 2007-05-01 17:12:41.000000000 +1000 +++ linux-2.6.21-uc0/arch/m68knommu/platform/5307/timers.c 2007-05-01 17:16:11.000000000 +1000 @@ -62,10 +62,13 @@ /***************************************************************************/ +static int ticks_per_intr; + void coldfire_timer_init(irq_handler_t handler) { __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 | MCFTIMER_TMR_RESTART | MCFTIMER_TMR_ENABLE, TA(MCFTIMER_TMR)); @@ -81,11 +84,10 @@ unsigned long coldfire_timer_offset(void) { - unsigned long trr, tcn, offset; + unsigned long tcn, offset; tcn = __raw_readw(TA(MCFTIMER_TCN)); - trr = __raw_readtrr(TA(MCFTIMER_TRR)); - offset = (tcn * (1000000 / HZ)) / trr; + offset = ((tcn + 1) * (1000000 / HZ)) / ticks_per_intr; /* Check if we just wrapped the counters and maybe missed a tick */ if ((offset < (1000000 / HZ / 2)) && mcf_timerirqpending(1)) - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/