Re: [coreboot] [PATCH] 440BX registered SDRAM support

[Keith Hui]

On Tue, Mar 29, 2011 at 5:34 PM, Stefan Reinauer
 wrote:
> Keith Hui  [110329 06:11]:
> > > > if ((edosd & 0x84) == 0x84) {
> > > > edosd = 0x10; // Registered SDRAM
> > > > } else {
> > > > // Clear [4:3] in case it's EDO.
> > > > edosd &= 0x07;
> > > >
> > > > +//    } else if (edosd & 0x02) {
> > >
> > > Besides being commented out, this piece of code would never be executed,
> > > as there already is an else case.
> > > Also, modifying edosd in place is semi nice.
> >
> > So is this good, not so good, or bad?
> >
> > I want to know if I should split up edosd.
>
> Please do.

And so I did. Signoff in the patch.

edosd was a romcc-inspired trick because variables were a scarce resource.

The nbxecc simplification in this patch completed one full pass of
memtest86+ each with a regular and registered ECC DIMM installed.

With this patch the 440BX romstage is 60 bytes smaller, freeing up an
extra 64 bytes in the image.

Thanks
Keith