[coreboot] [RFC] port bochs-bios to gcc

Kevin O'Connor kevin at koconnor.net
Tue Feb 26 02:18:59 CET 2008

On Mon, Feb 25, 2008 at 01:35:18PM +0900, Jun Koi wrote:
> Hi Kevin,
> On 2/22/08, Kevin O'Connor <kevin at koconnor.net> wrote:
> > FYI.  I'm interested in reviving the ADLO effort.  I sent the
> >  following email to the bochs developers mailing list.
> >
> I think one of the reasons why they wrote the BIOS in asm is because
> it makes the result code small, as the size is limited in 64KB. What
> do you do to make sure that the ported code stays within the limit?
> Even if it is now, how about future, when you want to add more code?

Hi Jun,

My plan was to move all of the initialization code to 32bit mode.
That is why the first thing the code does is transition to 32bits.
The init code could then be relocated to anywhere in ram.  That would
leave the entire 0xf0000 block available for the real-mode irq

That said, I'm finding the gcc generated code to be significantly
smaller than the existing code.  I figure I'm more than half way
through porting of features, and I've used only about a fourth of the
available space.


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