Thanks Stefano,
On 09/18/2012 07:42 AM, Stefano Babic wrote:
On 18/09/2012 16:02, Eric Nelson wrote:
Hi Fabio and Stefano,
While trying to understand this, I wonder whether the use of overwrite_console() addresses Wolfgang's original concern.
I think the suggestion was to set the preboot variable to change things:
Wolfgang's first concern was to avoid to hardcode variable inside the code, as it was done in the original mx51 / mx53 code (and not only in i.MX boards).
#define CONFIG_PREBOOT "setenv stdout serial"
This makes sense if you want maintain the possibility that u-boot output is displayed on the LCD. Is this really the case ?
Sometimes it is.
We have customers of SABRE Lite that are new to embedded who have had to purchase serial adapters upon receiving their boards, though this is rare.
The other main use case is simpler: a serial port isn't hooked up during boot (i.e. in a production environment). In production, it would be more convenient to hook up a USB keyboard if needed.
In most cases, we want to display a splashscreen, while the console is still managed by serial line.
If this is the case, adding overwrite_console() tells video subsystem to not change the stdout variable, and then it is not required to set it back to serial neither in code nor with the help of the preboot variable.
The has the benefit of allowing saveenv to completely overwrite the decision.
Am I over-thinking this?
It depends if you want also U-Boot's output on the display or only a picture.
I'll rework the patch with overwrite_console() and keep these options in mind.
Thanks for the tips.
Regards,
Eric