diff options
author | Simon Glass <sjg@chromium.org> | 2020-07-10 03:43:14 +0300 |
---|---|---|
committer | Bin Meng <bmeng.cn@gmail.com> | 2020-07-17 09:32:24 +0300 |
commit | e1ddf67cb3982b5c49c1165da87917a82a285783 (patch) | |
tree | 1361a00a2d8d7a282be4e6c529539ecd8acabc70 | |
parent | ce04a9020c41a2ebf1d85e01532da69d2d2e2119 (diff) | |
download | u-boot-e1ddf67cb3982b5c49c1165da87917a82a285783.tar.xz |
timer: Allow delays with a 32-bit microsecond timer
The current get_timer_us() uses 64-bit arithmetic on 32-bit machines.
When implementing microsecond-level timeouts, 32-bits is plenty. Add a
new function that uses an unsigned long. On 64-bit machines this is
still 64-bit, but this doesn't introduce a penalty. On 32-bit machines
it is more efficient.
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>
-rw-r--r-- | include/time.h | 11 | ||||
-rw-r--r-- | lib/time.c | 5 |
2 files changed, 16 insertions, 0 deletions
diff --git a/include/time.h b/include/time.h index e99f9c8012..3f00e68713 100644 --- a/include/time.h +++ b/include/time.h @@ -17,6 +17,17 @@ unsigned long get_timer(unsigned long base); unsigned long timer_get_us(void); uint64_t get_timer_us(uint64_t base); +/** + * get_timer_us_long() - Get the number of elapsed microseconds + * + * This uses 32-bit arithmetic on 32-bit machines, which is enough to handle + * delays of over an hour. For 64-bit machines it uses a 64-bit value. + * + *@base: Base time to consider + *@return elapsed time since @base + */ +unsigned long get_timer_us_long(unsigned long base); + /* * timer_test_add_offset() * diff --git a/lib/time.c b/lib/time.c index 65db0f6cda..47f8c84327 100644 --- a/lib/time.c +++ b/lib/time.c @@ -152,6 +152,11 @@ uint64_t __weak get_timer_us(uint64_t base) return tick_to_time_us(get_ticks()) - base; } +unsigned long __weak get_timer_us_long(unsigned long base) +{ + return timer_get_us() - base; +} + unsigned long __weak notrace timer_get_us(void) { return tick_to_time(get_ticks() * 1000); |