[U-Boot] lcd-console / display rotation

[Hannes Petermaier]

> 
> +Anatolij, Nikita
> 
> Hi,
Hi,
many thanks for response.

> 
> On 2 March 2015 at 03:12, Hannes Petermaier
> <Hannes.Petermaier at br-automation.com> wrote:
> > Hello everybody,
> >
> > A short question about lcd-console:
> >
> > Today u-boot only supports a 'linear framebuffer', meaning the next 
pixel
> > of a character is allways right after left and the framebuffer address 
is
> > incrementing.
> > We call this the display is mounted with 0° rotation.
> >
> > In some cases we have a rotated display.
> > Maybe rotated by 90° to have portrait mode or even 180° due to 
mechanical
> > issues.
> >
> > My question is:
> > Is anybody currently working around this, having rotated display ?
> > If not so, i would like start a implementation.
> >
> > 180° is quite easy, we only need to add some offset (total len of
> > framebuffer) to our framebuffer base address and do -- instead ++ for
> > drawing characters. Font can be reused.
> >
> > In the other cases, 90° and 270° it will maybe a bit tricky. I think a
> > ?rotated font? is also necessary.
> >
> > Of course we have to think about the other functions like scroll 
up/down.
> 
> I don't know of anything, but it sounds useful.
Okay, Anatolij doesn't also know anything that there is something going 
on.
I will start to form some ideas how to implement such feature.

> 
> Also I wonder if some hardware has support for this?
"Support" is the wrong word, sometimes the the lcd is mechanical built in 
rotated and the logical start of the framebuffer isn't as usual at 
top-left, rather it it bottom-right - means rotated by 180°.
> 
> Nikita (on CC) is tidying up this part of U-Boot so get in touch with 
him.
Nikita, whats your opinion around that ?

> Regards,
> Simon
best regards,
Hannes