diff options
| author | David Woodhouse <David.Woodhouse@intel.com> | 2015-09-09 11:58:59 +0100 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2015-10-15 11:24:45 +0100 |
| commit | ae853ddb9ad5e7c01cad3fbf016040acd961f407 (patch) | |
| tree | 7d48a76f8849125e95dcddc5b29937317537abd5 /drivers/iommu/intel-iommu.c | |
| parent | d14053b3c714178525f22660e6aaf41263d00056 (diff) | |
iommu/vt-d: Introduce intel_iommu=pasid28, and pasid_enabled() macro
As long as we use an identity mapping to work around the worst of the
hardware bugs which caused us to defeature it and change the definition
of the capability bit, we *can* use PASID support on the devices which
advertised it in bit 28 of the Extended Capability Register.
Allow people to do so with 'intel_iommu=pasid28' on the command line.
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/iommu/intel-iommu.c')
| -rw-r--r-- | drivers/iommu/intel-iommu.c | 20 |
1 files changed, 14 insertions, 6 deletions
diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 17b4744628ab..6a01735f4df3 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -497,13 +497,21 @@ static int dmar_forcedac; static int intel_iommu_strict; static int intel_iommu_superpage = 1; static int intel_iommu_ecs = 1; +static int intel_iommu_pasid28; +static int iommu_identity_mapping; + +#define IDENTMAP_ALL 1 +#define IDENTMAP_GFX 2 +#define IDENTMAP_AZALIA 4 /* We only actually use ECS when PASID support (on the new bit 40) * is also advertised. Some early implementations — the ones with * PASID support on bit 28 — have issues even when we *only* use * extended root/context tables. */ +#define pasid_enabled(iommu) (ecap_pasid(iommu->ecap) || \ + (intel_iommu_pasid28 && ecap_broken_pasid(iommu->ecap))) #define ecs_enabled(iommu) (intel_iommu_ecs && ecap_ecs(iommu->ecap) && \ - ecap_pasid(iommu->ecap)) + pasid_enabled(iommu)) int intel_iommu_gfx_mapped; EXPORT_SYMBOL_GPL(intel_iommu_gfx_mapped); @@ -566,6 +574,11 @@ static int __init intel_iommu_setup(char *str) printk(KERN_INFO "Intel-IOMMU: disable extended context table support\n"); intel_iommu_ecs = 0; + } else if (!strncmp(str, "pasid28", 7)) { + printk(KERN_INFO + "Intel-IOMMU: enable pre-production PASID support\n"); + intel_iommu_pasid28 = 1; + iommu_identity_mapping |= IDENTMAP_GFX; } str += strcspn(str, ","); @@ -2403,11 +2416,6 @@ found_domain: return domain; } -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, unsigned long long end) |