[coreboot] qemu dts fixes

Myles Watson mylesgw at gmail.com
Tue Dec 2 04:45:09 CET 2008

> -----Original Message-----
> From: Jordan Crouse [mailto:jordan at cosmicpenguin.net]
> Sent: Monday, December 01, 2008 4:29 PM
> To: Myles Watson
> Cc: coreboot at coreboot.org
> Subject: Re: [coreboot] qemu dts fixes
> Myles Watson wrote:
> > On Mon, Dec 1, 2008 at 1:52 PM, Jordan Crouse
> <jordan at cosmicpenguin.net>wrote:
> >
> >> Myles Watson wrote:
> >>
> >>> This patch updates qemu.  It takes out the bus construct from the dts,
> >>> adds
> >>> the dts for ide, isa, and acpi.  It changes the default for ide to
> >>> enabled.
> >>> It makes it so that only the plugged in cards are dynamic.
> >>>
> >>> Since it's harder in emulation to tell if chips are cards or on the
> >>> mainboard, I may be wrong with the VGA card.  Help?
> >>>
> >> Excuse my ignorance, but why does it matter?   They are on the PCI bus
> >> regardless of where the logic lives, right?
> >
> >
> > It matters for the expansion ROM.  If it's onboard, then coreboot has to
> > include it in the lar, otherwise it just reads the "card's" ROM.  It
> also
> > changes the logic of whether or not we set subsytem IDs.
> So the defining criteria isn't "onboard or cards", its "need a ROM or
> not" - because not all onboard GPUs require an option ROM in the main
> system ROM - some can use an attached EEPROM (as do soldered down NICs
> and other such devices).

I guess the other thing is that you might want to throw an error if
something that's soldered on doesn't respond (and it won't change
addresses), but you won't even know if someone moves a card from slot to
slot or plugs in a new one.

> Its not a huge deal, since I see where you are doing with it - but it
> might relieve some confusion if we called it "need_optionrom" instead of
> "on_mainboard".

It's carried over from v2, but now is the time to change things that don't
make sense.


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