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Diffstat (limited to 'drivers/pci/intel-iommu.c')
-rw-r--r--drivers/pci/intel-iommu.c82
1 files changed, 77 insertions, 5 deletions
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c
index 855dd7ca47f3..b1e97e682500 100644
--- a/drivers/pci/intel-iommu.c
+++ b/drivers/pci/intel-iommu.c
@@ -48,6 +48,7 @@
#define IS_GFX_DEVICE(pdev) ((pdev->class >> 16) == PCI_BASE_CLASS_DISPLAY)
#define IS_ISA_DEVICE(pdev) ((pdev->class >> 8) == PCI_CLASS_BRIDGE_ISA)
+#define IS_AZALIA(pdev) ((pdev)->vendor == 0x8086 && (pdev)->device == 0x3a3e)
#define IOAPIC_RANGE_START (0xfee00000)
#define IOAPIC_RANGE_END (0xfeefffff)
@@ -94,6 +95,7 @@ static inline unsigned long virt_to_dma_pfn(void *p)
/* global iommu list, set NULL for ignored DMAR units */
static struct intel_iommu **g_iommus;
+static void __init check_tylersburg_isoch(void);
static int rwbf_quirk;
/*
@@ -1934,6 +1936,9 @@ error:
}
static int iommu_identity_mapping;
+#define IDENTMAP_ALL 1
+#define IDENTMAP_GFX 2
+#define IDENTMAP_AZALIA 4
static int iommu_domain_identity_map(struct dmar_domain *domain,
unsigned long long start,
@@ -2151,8 +2156,14 @@ static int domain_add_dev_info(struct dmar_domain *domain,
static int iommu_should_identity_map(struct pci_dev *pdev, int startup)
{
- if (iommu_identity_mapping == 2)
- return IS_GFX_DEVICE(pdev);
+ if ((iommu_identity_mapping & IDENTMAP_AZALIA) && IS_AZALIA(pdev))
+ return 1;
+
+ if ((iommu_identity_mapping & IDENTMAP_GFX) && IS_GFX_DEVICE(pdev))
+ return 1;
+
+ if (!(iommu_identity_mapping & IDENTMAP_ALL))
+ return 0;
/*
* We want to start off with all devices in the 1:1 domain, and
@@ -2332,11 +2343,14 @@ int __init init_dmars(void)
}
if (iommu_pass_through)
- iommu_identity_mapping = 1;
+ iommu_identity_mapping |= IDENTMAP_ALL;
+
#ifdef CONFIG_DMAR_BROKEN_GFX_WA
- else
- iommu_identity_mapping = 2;
+ iommu_identity_mapping |= IDENTMAP_GFX;
#endif
+
+ check_tylersburg_isoch();
+
/*
* If pass through is not set or not enabled, setup context entries for
* identity mappings for rmrr, gfx, and isa and may fall back to static
@@ -3670,3 +3684,61 @@ static void __devinit quirk_iommu_rwbf(struct pci_dev *dev)
}
DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x2a40, quirk_iommu_rwbf);
+
+/* 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
+ this in a function called from init_dmars(), instead of in a PCI
+ quirk, because we don't want to print the obnoxious "BIOS broken"
+ message if VT-d is actually disabled.
+*/
+static void __init check_tylersburg_isoch(void)
+{
+ struct pci_dev *pdev;
+ uint32_t vtisochctrl;
+
+ /* If there's no Azalia in the system anyway, forget it. */
+ pdev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x3a3e, NULL);
+ if (!pdev)
+ return;
+ pci_dev_put(pdev);
+
+ /* System Management Registers. Might be hidden, in which case
+ we can't do the sanity check. But that's OK, because the
+ known-broken BIOSes _don't_ actually hide it, so far. */
+ pdev = pci_get_device(PCI_VENDOR_ID_INTEL, 0x342e, NULL);
+ if (!pdev)
+ return;
+
+ if (pci_read_config_dword(pdev, 0x188, &vtisochctrl)) {
+ pci_dev_put(pdev);
+ return;
+ }
+
+ pci_dev_put(pdev);
+
+ /* If Azalia DMA is routed to the non-isoch DMAR unit, fine. */
+ if (vtisochctrl & 1)
+ return;
+
+ /* Drop all bits other than the number of TLB entries */
+ vtisochctrl &= 0x1c;
+
+ /* If we have the recommended number of TLB entries (16), fine. */
+ if (vtisochctrl == 0x10)
+ return;
+
+ /* Zero TLB entries? You get to ride the short bus to school. */
+ if (!vtisochctrl) {
+ WARN(1, "Your BIOS is broken; DMA routed to ISOCH DMAR unit but no TLB space.\n"
+ "BIOS vendor: %s; Ver: %s; Product Version: %s\n",
+ dmi_get_system_info(DMI_BIOS_VENDOR),
+ dmi_get_system_info(DMI_BIOS_VERSION),
+ dmi_get_system_info(DMI_PRODUCT_VERSION));
+ iommu_identity_mapping |= IDENTMAP_AZALIA;
+ return;
+ }
+
+ printk(KERN_WARNING "DMAR: Recommended TLB entries for ISOCH unit is 16; your BIOS set %d\n",
+ vtisochctrl);
+}