> -----Original Message----- > From: Joerg Roedel [mailto:joro@xxxxxxxxxx] > Sent: Friday, April 07, 2017 10:32 AM > To: Bjorn Helgaas > Cc: linux-pci@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx; Daniel Drake; > Deucher, Alexander; Samuel Sieb; David Woodhouse; Joerg Roedel > Subject: [PATCH v2] PCI: Add ATS-disable quirk for AMD Stoney GPUs > > From: Joerg Roedel <jroedel@xxxxxxx> > > ATS is broken on this hardware and causes IOMMU stalls and > system failure. Disable ATS on these devices to make them > usable again with IOMMU enabled. > > Note that the commit in the Fixes-tag is not buggy, it > just uncovers the problem in the hardware by increasing > the ATS-flush rate. > > Fixes: b1516a14657a ('iommu/amd: Implement flush queue') > Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Acked-by: Alex Deucher <alexander.deucher@xxxxxxx> > --- > drivers/pci/quirks.c | 19 +++++++++++++++++++ > 1 file changed, 19 insertions(+) > > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c > index 6736836..7cbe316 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); > + > +#ifdef CONFIG_PCI_ATS > +/* > + * 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) > +{ > + /* > + * Set pdev->ats_cap = 0 to make pci_enable_ats() bail out > + * early. > + */ > + dev_info(&pdev->dev, "QUIRK: Disabling ATS"); > + pdev->ats_cap = 0; > +} > + > +/* AMD Stoney platform GPU */ > +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_ATI, 0x98e4, > quirk_disable_ats); > +#endif /* CONFIG_PCI_ATS */ > -- > 1.9.1
