time: move the CONFIG_SYS_TIMER_RATE handling to the compiler

CONFIG_SYS_TIMER_RATE might be a dynamic value, i.e. a function call
instead of a static value, thus it has to be evaluated at runtime. If it
is a static value, the compiler should be able to optimize the unused
branches out.

This will be needed for kirkwoods dynamic CONFIG_SYS_TCLK setting.

Cc: Pali Rohár <pali@kernel.org>
Signed-off-by: Michael Walle <michael@walle.cc>
Reviewed-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Stefan Roese <sr@denx.de>
This commit is contained in:
Michael Walle 2022-08-17 21:37:48 +02:00 committed by Stefan Roese
parent 7875f8019c
commit 616278bd2c

View file

@ -47,12 +47,15 @@ ulong timer_get_boot_us(void)
{
ulong count = timer_read_counter();
#if CONFIG_SYS_TIMER_RATE == 1000000
return count;
#elif CONFIG_SYS_TIMER_RATE > 1000000
return lldiv(count, CONFIG_SYS_TIMER_RATE / 1000000);
#elif defined(CONFIG_SYS_TIMER_RATE)
return (unsigned long long)count * 1000000 / CONFIG_SYS_TIMER_RATE;
#ifdef CONFIG_SYS_TIMER_RATE
const ulong timer_rate = CONFIG_SYS_TIMER_RATE;
if (timer_rate == 1000000)
return count;
else if (timer_rate > 1000000)
return lldiv(count, timer_rate / 1000000);
else
return (unsigned long long)count * 1000000 / timer_rate;
#else
/* Assume the counter is in microseconds */
return count;