Re: [PATCH] PCI: Add ATS-disable quirk for AMD Stoney GPUs

[Joerg Roedel <jroedel@suse.de>]

On Fri, Apr 07, 2017 at 02:53:05PM +0200, David Woodhouse wrote:
> On Fri, 2017-04-07 at 14:40 +0200, Joerg Roedel wrote:
> > 
> > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c
> > index 6736836..3bc9856 100644
> > --- a/drivers/pci/quirks.c
> > +++ b/drivers/pci/quirks.c
> > @@ -4634,3 +4634,22 @@ static void quirk_no_aersid(struct pci_dev *pdev)
> >  DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2031, quirk_no_aersid);
> >  DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2032, quirk_no_aersid);
> >  DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, 0x2033, quirk_no_aersid);
> > +
> > +/*
> > + * Some devices have a broken ATS implementation causing IOMMU stalls.
> > + * Don't use ATS for those devices.
> > + */
> > +static void quirk_disable_ats(struct pci_dev *pdev)
> > +{
> > +#ifdef CONFIG_PCI_ATS
> > +       /*
> > +        * Set pdev->ats_cap = 0 to make pci_enable_ats() bail out
> > +        * early.
> > +        */
> > +       dev_info(&pdev->dev, "QUIRK: Disabling ATS");
> > +       pdev->ats_cap = 0;
> > +#endif
> > +}
> > +
> > +/* AMD Stoney platform GPU */
> > +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x98e4, quirk_disable_ats);
> 
> Why not put the #ifdef around *all* of the above?

Good point, I'll change that.