[U-Boot] OMAP3, RFBI, splash screen

[U-Boot] OMAP3, RFBI, splash screen

[Sergey Lapin]

Hi, all!

I'm trying to implement splash screen on OMAP35xx-based device
with 128x128 1bpp display connected using RFBI, plain parallel interface.
Display has controller and own memory, and is controlled with parallel
interface, 8-bit wide data bus and signals.

This display works under Linux, but I can't implement
that using u-boot, display just doesn't power on, while I see
that data is on bus with oscilloscope. Linux version works
using interrupts, so I can't do this with u-boot, and that'd be simply
overkill using this in u-boot. I think I miss something simple.

Have anybody implemented such a thing, I just need to make
it into dumb parallel mode, just to display simple image.
Any examples, ideas?

All the best,
S.

[U-Boot] OMAP3, RFBI, splash screen

[Dirk Behme]

Sergey Lapin wrote:
> Hi, all!
> 
> I'm trying to implement splash screen on OMAP35xx-based device
> with 128x128 1bpp display connected using RFBI, plain parallel interface.
> Display has controller and own memory, and is controlled with parallel
> interface, 8-bit wide data bus and signals.
> 
> This display works under Linux, but I can't implement
> that using u-boot, display just doesn't power on, while I see
> that data is on bus with oscilloscope. Linux version works
> using interrupts, so I can't do this with u-boot, and that'd be simply
> overkill using this in u-boot. I think I miss something simple.
> 
> Have anybody implemented such a thing, I just need to make
> it into dumb parallel mode, just to display simple image.
> Any examples, ideas?

Most probably it won't help you, as it seems you have some HW 
configuration issues. But for OMAP3 splash screen example see

http://groups.google.com/group/beagleboard/browse_thread/thread/3ad9b803a3418624

Best regards

Dirk

[U-Boot] OMAP3, RFBI, splash screen

[Nishanth Menon]

Try2: to list..
On Fri, Sep 18, 2009 at 11:08 AM, Dirk Behme <dirk.behme@googlemail.com> wrote:
>
> Sergey Lapin wrote:
> > Hi, all!
> >
> > I'm trying to implement splash screen on OMAP35xx-based device
> > with 128x128 1bpp display connected using RFBI, plain parallel interface.
> > Display has controller and own memory, and is controlled with parallel
> > interface, 8-bit wide data bus and signals.
> >
> > This display works under Linux, but I can't implement
> > that using u-boot, display just doesn't power on, while I see
> > that data is on bus with oscilloscope. Linux version works
> > using interrupts, so I can't do this with u-boot, and that'd be simply
> > overkill using this in u-boot. I think I miss something simple.
> >
> > Have anybody implemented such a thing, I just need to make
> > it into dumb parallel mode, just to display simple image.
> > Any examples, ideas?
>
> Most probably it won't help you, as it seems you have some HW
> configuration issues. But for OMAP3 splash screen example see
>
> http://groups.google.com/group/beagleboard/browse_thread/thread/3ad9b803a3418624
Just FYI -> RFBI is pretty easy to configure up.. I dont recollect
seeing (Display Sub System) DSS support in mainline u-boot though..
Usually for RFBI display, there is a few configuration sequences you
need to do using RFBI CMD reg and is very display specific, followed
by filling up the screen with the data you need -> also note for
backlight, based on the board, you may need to look at the schematics
for required
gpio line to toggle to the right position.. you can usually reverse
engineer it from the corresponding linux driver for the same.. if you
have it.. also ensure you have the pin mux done correctly..

Regards,
Nishanth Menon