diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/pci/dmar.c | 10 | ||||
| -rw-r--r-- | drivers/pci/intel-iommu.c | 22 |
2 files changed, 32 insertions, 0 deletions
diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c index 5f164ff3026..f5a662a50ac 100644 --- a/drivers/pci/dmar.c +++ b/drivers/pci/dmar.c @@ -491,6 +491,7 @@ int alloc_iommu(struct dmar_drhd_unit *drhd) int map_size; u32 ver; static int iommu_allocated = 0; + int agaw; iommu = kzalloc(sizeof(*iommu), GFP_KERNEL); if (!iommu) @@ -506,6 +507,15 @@ int alloc_iommu(struct dmar_drhd_unit *drhd) iommu->cap = dmar_readq(iommu->reg + DMAR_CAP_REG); iommu->ecap = dmar_readq(iommu->reg + DMAR_ECAP_REG); + agaw = iommu_calculate_agaw(iommu); + if (agaw < 0) { + printk(KERN_ERR + "Cannot get a valid agaw for iommu (seq_id = %d)\n", + iommu->seq_id); + goto error; + } + iommu->agaw = agaw; + /* the registers might be more than one page */ map_size = max_t(int, ecap_max_iotlb_offset(iommu->ecap), cap_max_fault_reg_offset(iommu->cap)); diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index 9dca689215e..3ecfa2304c2 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -362,6 +362,28 @@ void free_iova_mem(struct iova *iova) kmem_cache_free(iommu_iova_cache, iova); } + +static inline int width_to_agaw(int width); + +/* calculate agaw for each iommu. + * "SAGAW" may be different across iommus, use a default agaw, and + * get a supported less agaw for iommus that don't support the default agaw. + */ +int iommu_calculate_agaw(struct intel_iommu *iommu) +{ + unsigned long sagaw; + int agaw = -1; + + sagaw = cap_sagaw(iommu->cap); + for (agaw = width_to_agaw(DEFAULT_DOMAIN_ADDRESS_WIDTH); + agaw >= 0; agaw--) { + if (test_bit(agaw, &sagaw)) + break; + } + + return agaw; +} + /* in native case, each domain is related to only one iommu */ static struct intel_iommu *domain_get_iommu(struct dmar_domain *domain) { |