Hi Johan,
Johan Hovold 於 2018/1/9 下午 07:08 寫道:
On Thu, Jan 04, 2018 at 10:29:17AM +0800, Ji-Ze Hong (Peter Hong) wrote:
The F81532/534 had 4 clocksource 1.846/18.46/14.77/24MHz and baud rates
can be up to 1.5Mbits with 24MHz.
This device may generate data overrun when baud rate setting to 921600bps
or higher with old UART trigger level setting (8x14=112) with full
loading. We'll change trigger level from 8x14=112 to 8x8=64 to avoid data
overrun.
Also the read/write of EP0 will be affected by this patch. The worst case
of responding time is 20s when all serial port are full loading and trying
to access EP0, so we change EP0 timeout from 10 to 20s.
Surely you meant 1 and 2 seconds respectively here? And if you have
indeed measured response times close to 2000 ms then perhaps you want to
add even more margin?
Normally, the communication with F81534 ep0 will take less than 1 sec
(even only some milliseconds), but It maybe take much long time with
huge loading with UART functional.
We had tested it on BurnInTest, 4 ports with 921600bps + MSR status
check to perform huge loading test. The worst case to read MSR register
via ep0 will take 15~18 seconds. So We'll still remain the max waiting
time for access ep0 with 2x10=20s in high baud rate mode.
Thanks
--
With Best Regards,
Peter Hong
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