Re: [coreboot] Resource Allocation discussion

[Myles Watson]

On Tue, Dec 2, 2008 at 11:44 AM, Marc Jones  wrote:
> On Tue, Dec 2, 2008 at 6:57 AM, Myles Watson  wrote:
> > > -----Original Message-----
> > > From: Marc Jones [mailto:[e-mail]]
> > > Sent: Monday, December 01, 2008 10:42 PM
> > > To: Myles Watson
> > > Cc: Coreboot
> > > Subject: Re: [coreboot] Resource Allocation discussion
> > >
> > > Hi Myles,
> > > I will try to help..... :)
> > >
> > > On Mon, Dec 1, 2008 at 2:37 PM, Myles Watson  wrote:
> > > > The resource patches I submitted work fairly well, but still need a
> > >
> > > little
> > > > help.
> > > >
> > > > I haven't touched subtractively decoded resources, and that's where
>
> the
> > > > breakage is right now.
> > > >
> > > > Questions:
> > > > Who should have a resource that moves all other IO resources above
> > >
> > > 0x400
> > > > or 0x1000?
> > >
> > > What do you mean? By definition the subtractive port takes all
> > > unclaimed cycles. There should be a LPC or ISA bridge in the
> > > southbridge that forwards cycles that the legacy southbridge devices
> > > don't claim.
> >
> > Sorry.  I wasn't clear enough again.  What I meant was something more
>
> like:
> > Since the resource allocation algorithm can't avoid resources that it
> > doesn't know about, who decides if the subtractive area to avoid is
> > 0x0-0x400, 0x0-0x1000, or some other range?  If I declare some device to
> > hold these addresses so that no other resource ends up there, should it
>
> be
> > subtractive?  I'm inclined to put it in the domain or in the SuperIO.
>
> I think it belongs in the southbridge lpc/isa device which is in the
> domain. It should be 0x0-0x1000.

So like this? For qemu:

static void i82371eb_isa_read_resources(struct device *dev)
{
    struct resource *res;
    res = new_resource(dev, IOINDEX_SUBTRACTIVE(0,0));
    res->base = 0x0UL;
    res->size = 0x1000UL;
    res->limit = 0xFFFUL;
    res->flags = IORESOURCE_MEM | IORESOURCE_SUBTRACTIVE |
             IORESOURCE_ASSIGNED | IORESOURCE_FIXED;
}

static void i82371eb_isa_set_resources(struct device *dev)
{
    struct resource *res;
    res = probe_resource(dev, IOINDEX_SUBTRACTIVE(0,0));
    res->flags |= IORESOURCE_STORED;
    pci_set_resources(dev);
}

Thanks for the help.

Myles