[U-Boot] [PATCH v2] NS16550: buffer reads

[Graeme Russ]

Hi Simon,

On Wed, Oct 26, 2011 at 10:17 AM, Simon Glass <sjg at chromium.org> wrote:

[big snip]

> Did I mention a can of worms? After 65 messages on this topic Scott's
> patch seems pretty appealing right now! We can even move it up a level
> in the s/w stack if that helps.

But I agree with Wolfgang that Scott's proposal only hides the real
problem even deeper and will make a real solution more difficult
next time around

> But to continue this a little, and donning my asbestos suit, should
> U-Boot have a CONFIG to enable an event loop called in delay
> functions, network functions, read/write operations, etc.? It would
> permit us to solve this problem properly I think, if we think it is
> worth solving. Not saying it is a good idea...

That is what the watchdog code does - It is a horrible hack, and every now
and again, another patch comes through which adds another call to the
watchdog trigger in some obscure loop in some obscure code location. Or
someone submits new code for a board that does not have a watchdog that
somebody else then uses on a board that does have one and the watchdog
suddenly triggers resetting the board. It's messy and ugly.

My biggest point about the 'dropped character' issue is that the fix is
simple provided the 'tasks' that use the serial console behave and inform
the serial console driver that they have finished receiving characters -
not a big ask in my opinion. Way smaller that spattering 'Check the
serial port' all over the code

Regards,

Graeme