Hi Bin,
On Thu, 9 Jul 2020 at 18:44, Bin Meng bmeng.cn@gmail.com wrote:
Hi Simon,
On Fri, Jul 10, 2020 at 8:28 AM Simon Glass sjg@chromium.org wrote:
Hi Bin,
On Tue, 7 Jul 2020 at 01:09, Bin Meng bmeng.cn@gmail.com wrote:
Hi Simon,
On Sat, Jul 4, 2020 at 12:38 AM Simon Glass sjg@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 sjg@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.
But that is not my objective here. I just want something that is efficient on both 32- and 64-bit systems.
Regards, Simon