Re: linux logo at startup

[Gurunandan R Bhat <grbhat@xxxxxxxxxxxxxxx>]

On Fri, 25 Jun 1999, N.A. Prakash wrote:

> Would somebody please explain what VBE 2.0 compliance and frame buffering 
> have to do with the ability to display the penguin logo at boot time?

The main difference between VBE 1.0 and VBE 2.0 (among others) is that VBE
2.0 routines in the Video BIOS come with protected mode wrappers. VBE 1.0
BIOS routines on the other hand are real mode routines. Since Linux gets
into protected mode at the earliest (very very early) opportunity, it
cannot call upon VBE 1.0 BIOS functions to do the display stuff.

Frame buffering (to the best of my understanding) is not a issue that has
any direct bearing on generating that bird. Frame buffering becomes
possible with VBE 2.0 since protected mode can address large (>> 64K)
regions of contiguous memory and real-mode bank switching of video memory
becomes redundant. One can therefore treat one contiguous thunk of memory
as a "frame buffer" and leave it to the fb driver to map it on to video
memory.

I hope this helps



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