Re: [PATCH] support PCI MCFG space on Intel i915 bridges

[Jesse Barnes <jesse.barnes@intel.com>]

On Sunday, April 29, 2007 7:10 pm Robert Hancock wrote:
> Jesse Barnes wrote:
> > Add support for Intel 915 bridge chips to the new PCI MMConfig
> > detection code.  Tested and works on my sole 915 based platform (a
> > Toshiba laptop).  I added register masking per Oliver's suggestion,
> > and moved the __init qualifier to after the 'static const char' to
> > match Ogawa-san's recent cleanup patches.
> >
> > Signed-off-by:  Jesse Barnes <jesse.barnes@intel.com>
> >
> > diff --git a/arch/i386/pci/mmconfig-shared.c
> > b/arch/i386/pci/mmconfig-shared.c index 747d8c6..1339d31 100644
> > --- a/arch/i386/pci/mmconfig-shared.c
> > +++ b/arch/i386/pci/mmconfig-shared.c
> > @@ -72,6 +72,26 @@ static const char __init *pci_mmcfg_e7520(void)
> >  	return "Intel Corporation E7520 Memory Controller Hub";
> >  }
> >
> > +static const char __init *pci_mmcfg_intel_915(void)
> > +{
> > +       u32 pciexbar, len = 0;
> > +
> > +       pci_conf1_read(0, 0, PCI_DEVFN(0,0), 0x48, 4, &pciexbar);
> > +
> > +       /* No enable bit or size field, so assume 256M range is
> > enabled. */ +       len = 0x10000000U;
>
> Check the 915 spec more carefully, there is an enable bit, it's in
> the DEVEN register offset 54h, the bit is called PCIEXBAREN (bit 31).
> If that is not set you should be setting pci_mmcfg_config_num to 0
> and bailing out.

Right, but you patch should obsolete this stuff anyway.  I'll test it 
out in the next few days.

Jesse