From 4de75cf9391b538bbfe7dc0a9782f1ebe8e242ad Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Thu, 24 Sep 2009 01:01:29 +0100 Subject: [PATCH 1/7] intel-iommu: Make "Unknown DMAR structure" message more informative We might as well print the type of the DMAR structure we don't know how to handle when skipping it. Then someone getting this message has a chance of telling whether the structure is just bogus, or if there really is something valid that the kernel doesn't know how to handle. Signed-off-by: Roland Dreier Signed-off-by: David Woodhouse --- drivers/pci/dmar.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c index 14bbaa17e2ca..d199bcabed75 100644 --- a/drivers/pci/dmar.c +++ b/drivers/pci/dmar.c @@ -461,7 +461,8 @@ parse_dmar_table(void) break; default: printk(KERN_WARNING PREFIX - "Unknown DMAR structure type\n"); + "Unknown DMAR structure type %d\n", + entry_header->type); ret = 0; /* for forward compatibility */ break; } From 17b6097753e926ca546189463070a7e94e7ea9fa Mon Sep 17 00:00:00 2001 From: Roland Dreier Date: Thu, 24 Sep 2009 12:14:00 -0700 Subject: [PATCH 2/7] intel-iommu: Decode (and ignore) RHSA entries I recently got a system where the DMAR table included a couple of RHSA (remapping hardware static affinity) entries. Rather than printing a message about an "Unknown DMAR structure," it would probably be more useful to dump the RHSA structure (as other DMAR structures are dumped). Signed-off-by: Roland Dreier Signed-off-by: David Woodhouse --- drivers/pci/dmar.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c index d199bcabed75..22b02c6df854 100644 --- a/drivers/pci/dmar.c +++ b/drivers/pci/dmar.c @@ -354,6 +354,7 @@ dmar_table_print_dmar_entry(struct acpi_dmar_header *header) struct acpi_dmar_hardware_unit *drhd; struct acpi_dmar_reserved_memory *rmrr; struct acpi_dmar_atsr *atsr; + struct acpi_dmar_rhsa *rhsa; switch (header->type) { case ACPI_DMAR_TYPE_HARDWARE_UNIT: @@ -375,6 +376,12 @@ dmar_table_print_dmar_entry(struct acpi_dmar_header *header) atsr = container_of(header, struct acpi_dmar_atsr, header); printk(KERN_INFO PREFIX "ATSR flags: %#x\n", atsr->flags); break; + case ACPI_DMAR_HARDWARE_AFFINITY: + rhsa = container_of(header, struct acpi_dmar_rhsa, header); + printk(KERN_INFO PREFIX "RHSA base: %#016Lx proximity domain: %#x\n", + (unsigned long long)rhsa->base_address, + rhsa->proximity_domain); + break; } } @@ -459,6 +466,9 @@ parse_dmar_table(void) ret = dmar_parse_one_atsr(entry_header); #endif break; + case ACPI_DMAR_HARDWARE_AFFINITY: + /* We don't do anything with RHSA (yet?) */ + break; default: printk(KERN_WARNING PREFIX "Unknown DMAR structure type %d\n", From e0fc7e0b4b5e69616f10a894ab9afff3c64be74e Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Wed, 30 Sep 2009 09:12:17 -0700 Subject: [PATCH 3/7] intel-iommu: Yet another BIOS workaround: Isoch DMAR unit with no TLB space Asus decided to ship a BIOS which configures sound DMA to go via the dedicated IOMMU unit, but assigns precisely zero TLB entries to that unit. Which causes the whole thing to deadlock, including the DMA traffic on the _other_ IOMMU units. Nice one. Signed-off-by: David Woodhouse --- drivers/pci/intel-iommu.c | 82 ++++++++++++++++++++++++++++++++++++--- 1 file 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 @@ static struct dmar_domain *get_domain_for_dev(struct pci_dev *pdev, int gaw) } 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); +} From 8d86fb2c80ec376b35ae64ac858d406ae1d42a3f Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Mon, 12 Oct 2009 12:48:43 +0100 Subject: [PATCH 4/7] Rename pci_init() to pci_apply_final_quirks(), move it to quirks.c This function may have done more in the past, but all it does now is apply the PCI_FIXUP_FINAL quirks. So name it sensibly and put it where it belongs. Signed-off-by: David Woodhouse --- drivers/pci/pci.c | 13 ------------- drivers/pci/quirks.c | 13 +++++++++++++ 2 files changed, 13 insertions(+), 13 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 6edecff0b419..2b575cfb4b09 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -2719,17 +2719,6 @@ int __attribute__ ((weak)) pci_ext_cfg_avail(struct pci_dev *dev) return 1; } -static int __devinit pci_init(void) -{ - struct pci_dev *dev = NULL; - - while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) { - pci_fixup_device(pci_fixup_final, dev); - } - - return 0; -} - static int __init pci_setup(char *str) { while (str) { @@ -2767,8 +2756,6 @@ static int __init pci_setup(char *str) } early_param("pci", pci_setup); -device_initcall(pci_init); - EXPORT_SYMBOL(pci_reenable_device); EXPORT_SYMBOL(pci_enable_device_io); EXPORT_SYMBOL(pci_enable_device_mem); diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 6099facecd79..014227540ac9 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2572,6 +2572,19 @@ void pci_fixup_device(enum pci_fixup_pass pass, struct pci_dev *dev) } pci_do_fixups(dev, start, end); } + +static int __devinit pci_apply_final_quirks(void) +{ + struct pci_dev *dev = NULL; + + while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) { + pci_fixup_device(pci_fixup_final, dev); + } + + return 0; +} + +device_initcall(pci_apply_final_quirks); #else void pci_fixup_device(enum pci_fixup_pass pass, struct pci_dev *dev) {} #endif From 00010268842bda320d43159324651c330e1e8136 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Mon, 12 Oct 2009 12:50:34 +0100 Subject: [PATCH 5/7] Mark pci_apply_final_quirks() __init rather than __devinit It doesn't get invoked on hotplug; it can be thrown away after init. Signed-off-by: David Woodhouse --- drivers/pci/quirks.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 014227540ac9..77bf620ba218 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2573,7 +2573,7 @@ void pci_fixup_device(enum pci_fixup_pass pass, struct pci_dev *dev) pci_do_fixups(dev, start, end); } -static int __devinit pci_apply_final_quirks(void) +static int __init pci_apply_final_quirks(void) { struct pci_dev *dev = NULL; From cf6f3bf7e587a00217d7509b440f694711c76b2e Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Mon, 12 Oct 2009 12:51:22 +0100 Subject: [PATCH 6/7] Run pci_apply_final_quirks() sooner. Having this as a device_initcall() means that some real device drivers can actually initialise _before_ the quirks are run, which is wrong. We want it to run _before_ device_initcall(), but _after_ fs_initcall(), since some arch-specific PCI initialisation like pcibios_assign_resources() is done at fs_initcall(). We could use rootfs_initcall() but I actually want to use that for the IOMMU initialisation, which has to come after the quirks, but still before the real devices. So use fs_initcall_sync() instead -- since this is entirely synchronous, it doesn't hurt that it'll escape the synchronisation. Signed-off-by: David Woodhouse --- drivers/pci/quirks.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c index 77bf620ba218..4e1b1b81f370 100644 --- a/drivers/pci/quirks.c +++ b/drivers/pci/quirks.c @@ -2584,7 +2584,7 @@ static int __init pci_apply_final_quirks(void) return 0; } -device_initcall(pci_apply_final_quirks); +fs_initcall_sync(pci_apply_final_quirks); #else void pci_fixup_device(enum pci_fixup_pass pass, struct pci_dev *dev) {} #endif From 9a821b231644028f8e2a853eb33d1184e925b183 Mon Sep 17 00:00:00 2001 From: David Woodhouse Date: Mon, 12 Oct 2009 12:59:29 +0100 Subject: [PATCH 7/7] x86: Move pci_iommu_init to rootfs_initcall() We want this to happen after the PCI quirks, which are now running at the very end of the fs_initcalls. This works around the BIOS problems which were originally addressed by commit db8be50c4307dac2b37305fc59c8dc0f978d09ea ('USB: Work around BIOS bugs by quiescing USB controllers earlier'), which was reverted in commit d93a8f829fe1d2f3002f2c6ddb553d12db420412. Signed-off-by: David Woodhouse --- arch/x86/kernel/pci-dma.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c index 64b838eac18c..e0d9199d0eb9 100644 --- a/arch/x86/kernel/pci-dma.c +++ b/arch/x86/kernel/pci-dma.c @@ -311,7 +311,7 @@ void pci_iommu_shutdown(void) amd_iommu_shutdown(); } /* Must execute after PCI subsystem */ -fs_initcall(pci_iommu_init); +rootfs_initcall(pci_iommu_init); #ifdef CONFIG_PCI /* Many VIA bridges seem to corrupt data for DAC. Disable it here */