Hi Simon, On Fri, Jul 10, 2020 at 8:28 AM Simon Glass <s...@chromium.org> wrote: > > Hi Bin, > > On Tue, 7 Jul 2020 at 01:09, Bin Meng <bmeng...@gmail.com> wrote: > > > > Hi Simon, > > > > On Sat, Jul 4, 2020 at 12:38 AM Simon Glass <s...@chromium.org> wrote: > > > > > > The current get_timer_us() uses 64-bit arithmetic. When implementing > > > microsecond-level timeouts, 32-bits is plenty. Add a new function to > > > support this. > > > > > > Signed-off-by: Simon Glass <s...@chromium.org> > > > --- > > > > > > (no changes since v1) > > > > > > include/time.h | 11 +++++++++++ > > > lib/time.c | 5 +++++ > > > 2 files changed, 16 insertions(+) > > > > > > diff --git a/include/time.h b/include/time.h > > > index e99f9c8012..434e63b075 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. > > > + * > > > + *@base: Base time to consider > > > + *@return elapsed time since @base > > > + */ > > > +unsigned long get_timer_us_long(unsigned long base); > > > > The function name does not clear indicates this is 32-bit value > > because unsigned long is still 64-bit when building for 64-bit U-Boot. > > Yes that's right. My purpose is to use the natural long time. > > Shall I update the commit message?
I think we need to explicitly declare the return value to u32 or uint32_t to make a 32-bit variant function. Regards, Bin
