-------------- Original message ----------------------
From: James Richard Tyrer <[EMAIL PROTECTED]>
> > -------------- Original message ---------------------- From: "Daniel 
> > Rozsnyó" <[EMAIL PROTECTED]>
> >> Patrick McNamara wrote:
> >>> Timothy Miller wrote:
> >>>> On 7/26/06, Richard Smith <[EMAIL PROTECTED]> wrote:
> >>>> 
> >>>>> As a linuxbios developer I'm nervious enough as is about with
> >>>>>  all this talk about making the RAM controller setup and
> >>>>> Video modes "Software" problems.
> >>>> No memory or video controllers are going to be running right on
> >>>>  reset. The only difference for us is that they're more complex
> >>>>  to program. Although Patrick's perl stuff is very complex, a 
> >>>> simple piece of C/asm code that converts timing numbers 
> >>>> directly to a video program would be very small.
> >>> Specifically it is 1667 bytes to generate the appropriate video 
> >>> controller binary image with arbitrary timing values.  That is 
> >>> when compiled with the stock gcc 3.4.5 optimizations.
> >>> 
> >> If the video-bios does support only the VGA modes (13 or how much 
> >> they are in the standard) then one can pre-generate the video 
> >> controller binary & store diffs for various modes. This might be 
> >> less, than a mode table + algoritm to generate the binary in 
> >> runtime.
> 
> [EMAIL PROTECTED] wrote:
> > Be careful about painting yourself into a corner.  OGD1 logic testing
> >  can begin with a limited set of VGA modes, but the final OGA1 design
> >  in TRV10/OGC1 will need to come to grips with providing a capability
> >  to power-up running any arbitrary video mode -- because some
> > monitors won't work any other way.  And remember,  part of the TRV10 
> > application space is embedded systems.  Cthulhu only knows what 
> > display systems it might have to drive.  Don't assume VESA mode 
> > compatibility.
> > 
> 
> I think that it is the other way around.  PC MotherBoards are going to 
> request a VGA mode that needs to be supported.  This VGA mode is only 
> used until the OS loads a graphics driver. Linux uses VGA/VESA for text 
> mode console so that is going to be needed unless we have a Kernel 
> driver for console mode.
> 
> OTOH, an embedded system that didn't boot with a VGA mode is going to 
> need to contain the code needed to load the driver to start up the 
> graphics card.  Such systems probably wouldn't even have a VGA/VESA 
> Video BIOS.
> 
> -- 
> JRT


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