Re: [PATCH 3/5] fbdev: sh_mobile_lcdc: increase maximum framebuffer

[Guennadi Liakhovetski <g.liakhovetski@gmx.de>]

On Mon, 27 Dec 2010, Magnus Damm wrote:

> Hi Guennadi,
> 
> On Sun, Dec 26, 2010 at 6:44 AM, Guennadi Liakhovetski
> <g.liakhovetski@gmx.de> wrote:
> > Paul, apart from increasing the fb size to 1080p, this patch also fixes a
> > regression, which leads to unusable by applications framebuffer on some
> > platforms, including migor. This happens, when one of parameters lies
> > outside of limits, being checked in sh_mobile_check_var(). On migor it is
> >
> >                .left_margin = 0,
> >
> > Then the fb-console is working, but, e.g., mplayer is not. So, we need
> > this patch in 2.6.37 too, please. Unfortunately, it also introduces a
> > wrong format printk format, which a later patch of yours fixes, so, you
> > might want to push that patch too, although, that's not that important.
> 
> It's great that you work on fixing this issue, thank you.
> 
> In the long run I wonder if it's best to try to get rid of the
> MAX_XRES/MAX_YRES stuff from the LCDC driver. I understand that you
> need to allocate the frame buffer memory early on, but it would be
> much better if the maximum values could be kept in platform data. The
> maximum resolution varies with CPU type, so a one-for-all modification
> like this may break older platforms.

Hm, I'l not sure how it can break other platforms. You mean they just will 
fail to allocate that much RAM? Otherwise it shouldn't cause any problems. 
But yes, I'll make an incremental patch to let platform override those 
values, and use defaults otherwise, would that be ok?

Thanks
Guennadi
---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/