From 9eecabcb9a924f1e11ba670365fd4babe423045c Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Tue, 21 Sep 2010 22:28:23 +0100 Subject: [PATCH] intel-iommu: Abort IOMMU setup for igfx if BIOS gave no shadow GTT space Yet another BIOS bug; Lenovo this time (X201). Red Hat bug #593516. Signed-off-by: David Woodhouse --- drivers/pci/intel-iommu.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+) diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index c3ceebb5be84..dee88c6cb3ef 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -3761,6 +3761,23 @@ static void __devinit quirk_iommu_rwbf(struct pci_dev *dev) DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2a40, quirk_iommu_rwbf); +static void __devinit quirk_calpella_no_shadow_gtt(struct pci_dev *dev) +{ + unsigned short ggc; + + if (pci_read_config_word(dev, 0x52, &ggc)) + return; + + if (!(ggc & 0x800)) { + printk(KERN_INFO "DMAR: BIOS has allocated no shadow GTT; disabling IOMMU for graphics\n"); + dmar_map_gfx = 0; + } +} +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0040, quirk_calpella_no_shadow_gtt); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0044, quirk_calpella_no_shadow_gtt); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x0062, quirk_calpella_no_shadow_gtt); +DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x006a, quirk_calpella_no_shadow_gtt); + /* On Tylersburg chipsets, some BIOSes have been known to enable the ISOCH DMAR unit for the Azalia sound device, but not give it any TLB entries, which causes it to deadlock. Check for that. We do -- GitLab