[U-Boot] xyz-modem: Change getc timeout loop waiting

[Alexander Sverdlin]

Hi!

On Wed, 1 Aug 2018 08:44:13 +0300
Tomas Melin <tomas.melin at vaisala.com> wrote:

> > This commit breaks YMODEM SPL->U-Boot boot on Beagle Bone,
> > transfer is aborted (because of timeout) after 497kb
> > (u-boot.img is around 570kb).
> > Reverting the commit repairs YMODEM boot.
> 
> Is the timeout a watchdog timeout or some communication freeze?

I suppose, it reports false-positive timeout back to ymodem code.
Because all it does is terminating communication gracefully (with 'C'
and a bunch of CANs).
I need to check if timer overflow is possible on Beaglebone,
because the code is obviously not overflow-proof, but on the
other hand it happens within minutes and at least the timer variable
is 32 bit...

> In case watchdog is correctly configured, kicking should still
> happen.

-- 
Alexander Sverdlin.