[U-Boot] Displaying characters on the display in u-boot

[Anatolij Gustschin]

Hi,

On Wed, 27 Mar 2013 21:05:55 +0530
Bhargav A K <bhargav.ak at sasken.com> wrote:
...
> > What U-Boot version do you use?
> 
> U-Boot 1.1.4-geb3fa991 (Feb 21 2013 - 10:11:04)
> (output of version command)

Very old, ;-).

> > This video_set_lut() function is only needed if you use 8 bits per
> > pixel frame buffer.
> 
> So can I comment it out, (or) just make a dummy call and dummy return from it.
> It wont affect my character(text) rendering on the display, correct ?

yes, just provide a dummy video_set_lut(). If you do not use the
GDF__8BIT_INDEX framebuffer format, the rendering will work.

> My last question, the board_video_init() function just initializes the board
> in display/video mode. For example if I have a GPIO to switch b/w command and
> video modes and a GPIO to switch on the LCD, etc., I'll have to do all such
> functions in it.
> 
> But if all of those are already done, I can just return a dummy from the
> function ?

Yes. If board specific video initialisation is done elsewhere the
board_video_init() can be a dummy function. Some video drivers
expect board_video_init() to return frame buffer base address but
i.e. in omap3 driver it returns 0 for successful video init or an
error code in case the board specific video init fails, thus
preventing further initialisation in the cfb_console driver.

Thanks,

Anatolij