[U-Boot] [U-Boot-Users] [PATCH] Allow console input to be disabled

Wolfgang Denk
2008-08-11T12:19:15Z

Dear Haavard Skinnemoen,

In message <20080811131944.500ef1e9@hskinnemo-gx745.norway.atmel.com> you wrote:
>
> The intention is to allow boards to use a single serial port for two
> purposes: Communicating with some other device (which will get really
> confused if u-boot interferes) and as a debug port. The user/developer
> must have a way to switch between the two roles, and if the first role
> is selected, u-boot must stay the hell away from the serial port.

I understand this. But then, the "silencing" should be done based on
the jumper setting ONLY, without any environment variable setting.

> The user will be able to switch between the two by means of an on-board
> jumper, so if he needs to interact with u-boot, he can simply flip the
> jumper and hook up a PC.

If the user typed "setenv silent=1;saveenv;reset" then hooking up a
PC will not help at all because he still has a "silent" board.

> But I guess there's another side-effect from this patch which is
> somewhat more nasty: The user can _also_ disable the debug port by
> simply setting an environment variable. That might be a bad idea, and
> probably not even necessary for Mark's purposes.

Now you get it. That's what the whole discussion is about. See
Detlev's posting that started it.

> So how about introducing a new flag, e.g. GD_FLG_DISABLE_CONSOLE, and
> use that instead? If set, it will disable both input and output, while
> GD_FLG_SILENT will just disable console output.

Sounds much better to me.

Best regards,

Wolfgang Denk

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