[U-Boot] [PATCH 7/9] at91rm9200: fix DCC support

Wolfgang Denk
2009-03-09T15:50:49Z

Dear Jean-Christophe PLAGNIOL-VILLARD,

In message <20090309120954.GK24237@game.jcrosoft.org> you wrote:
>
> > > > The #ifdef above does not seem to depend on DCC at all?
> >
> > You did not answer this question.
> >
> > > > And what does it hurt if we always shut down the console? To me that
> > > > looks clearer than an additional #ifdef.
> the UART code is not active or compile so you can't do it.

This statement makes no sense to me. If the #ifdef has any effect,
then this code is actually compiled. What would happen if the
statement would be executed?

Actually this is a question I repeat in all my replies to your
posting - what exactly is the problem with the current code? Does it
cause crashes or so? Or is it just that you think it is not necessary
because UARTs are not active?

> > So what if we use "DCC multi support"? (whatever this is - or do you
> > mean CONFIG_SERIAL_MULTI instead?)
> yes the DCC can be optionnaly compile with the CONFIG_SERIAL_MULTI support
> but not necessarely

So we should deal with this situation. To me it seems the current
patch does not do that.

> > You did not answer my question. Even if there is no need to shut it
> > down if it was not used - what does it hurt if we do this always?
> we can't because the code needed to do it is not even compiled

Come on.

We're discussing this part of your patch:

> +#if defined(CONFIG_DBGU) || defined(CONFIG_USART0) || defined(CONFIG_USART1)
> /*shutdown the console to avoid strange chars during reset */
> us->US_CR = (AT91C_US_RSTRX | AT91C_US_RSTTX);
> +#endif

If this code is not even compiled, then your patch that adds the "#if
defined / #endif" lines makes no sense at all.

If this code is compiled, then my question is, which problems are
cause by running the single statement:

us->US_CR = (AT91C_US_RSTRX | AT91C_US_RSTTX);

?

Best regards,

Wolfgang Denk

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