time: import time_after, time_before and friends from Linux
It is not safe to compare timer values directly.
On 32-bit systems, for example, timer_get_us() wraps around every
72 min. (2 ^ 32 / 1000000 =~ 4295 sec =~ 72 min). Depending on
the get_ticks() implementation, it may wrap more frequently.
The 72 min might be possible on the use of U-Boot.
Let's borrow time_after, time_before, and friends to solve the
wrap-around problem.
These macros were copied from include/linux/jiffies.h of Linux 4.9.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
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