[U-Boot] The abortboot routine misses key hits issued via netconsole.

[Michael Zaidman]

Hello,

The "Hit any key to stop autoboot:" of abortboot routine misses
the key hits issued via netconsole.
It happens due to delays of 10ms used to count passed seconds in
the abortboot routine of main.c file. All key events arrived
asynchronously during these delays are lost.

I solved it localy on my mpc8349 @ 514MHz based board by expanding
netloop receive window for netconsole case by 10 in nc_tstc routine and
eliminating 10ms delays from wait loop of abortboot routine when
compiled with CONFIG_NETCONSOLE and stdin configured to "nc".

This solution has following drawback - the Console multiplexing
(CONFIG_CONSOLE_MUX) will not work because it relates on tstc
immediate return. The mitigation factors are:
1) The console mutiplexing could not work anyway when is used with
netconsole due to the same limitation as in case with abortboot
explained above.
2) See CAVEATS in README.iomux;
3) Currently, AFAIK, console multiplexing is not used by any board.

Definitely, not resetting of the eth interface as discussed in
http://lists.denx.de/pipermail/u-boot/2010-January/067260.html
would be better solution but I am afraid its proper realization may
require significant effort under current IP stack architectural limitations.

Any thoughts/opinions/comments will be highly appreciated.

Regards,
Michael