diff options
| author | Sheng Yang <sheng@linux.intel.com> | 2009-03-18 15:33:05 +0800 |
|---|---|---|
| committer | David Woodhouse <David.Woodhouse@intel.com> | 2009-03-24 09:42:43 +0000 |
| commit | 58c610bd1a3f50820e45a7c09ec0e44d2cda15dd (patch) | |
| tree | 696539e1e17fd7600222865fa331e9144737a58b /drivers/pci | |
| parent | a1e4ee22863d41a6fbb24310d7951836cb6dafe7 (diff) | |
intel-iommu: Snooping control support
Snooping control enabled IOMMU to guarantee DMA cache coherency and thus reduce
software effort (VMM) in maintaining effective memory type.
Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Diffstat (limited to 'drivers/pci')
| -rw-r--r-- | drivers/pci/intel-iommu.c | 38 |
1 files changed, 33 insertions, 5 deletions
diff --git a/drivers/pci/intel-iommu.c b/drivers/pci/intel-iommu.c index f3f686581a9..be999ff025a 100644 --- a/drivers/pci/intel-iommu.c +++ b/drivers/pci/intel-iommu.c @@ -231,6 +231,7 @@ struct dmar_domain { int flags; /* flags to find out type of domain */ int iommu_coherency;/* indicate coherency of iommu access */ + int iommu_snooping; /* indicate snooping control feature*/ int iommu_count; /* reference count of iommu */ spinlock_t iommu_lock; /* protect iommu set in domain */ u64 max_addr; /* maximum mapped address */ @@ -421,7 +422,6 @@ static struct intel_iommu *domain_get_iommu(struct dmar_domain *domain) return g_iommus[iommu_id]; } -/* "Coherency" capability may be different across iommus */ static void domain_update_iommu_coherency(struct dmar_domain *domain) { int i; @@ -438,6 +438,29 @@ static void domain_update_iommu_coherency(struct dmar_domain *domain) } } +static void domain_update_iommu_snooping(struct dmar_domain *domain) +{ + int i; + + domain->iommu_snooping = 1; + + i = find_first_bit(&domain->iommu_bmp, g_num_of_iommus); + for (; i < g_num_of_iommus; ) { + if (!ecap_sc_support(g_iommus[i]->ecap)) { + domain->iommu_snooping = 0; + break; + } + i = find_next_bit(&domain->iommu_bmp, g_num_of_iommus, i+1); + } +} + +/* Some capabilities may be different across iommus */ +static void domain_update_iommu_cap(struct dmar_domain *domain) +{ + domain_update_iommu_coherency(domain); + domain_update_iommu_snooping(domain); +} + static struct intel_iommu *device_to_iommu(u8 bus, u8 devfn) { struct dmar_drhd_unit *drhd = NULL; @@ -1429,6 +1452,11 @@ static int domain_init(struct dmar_domain *domain, int guest_width) else domain->iommu_coherency = 0; + if (ecap_sc_support(iommu->ecap)) + domain->iommu_snooping = 1; + else + domain->iommu_snooping = 0; + domain->iommu_count = 1; /* always allocate the top pgd */ @@ -1557,7 +1585,7 @@ static int domain_context_mapping_one(struct dmar_domain *domain, spin_lock_irqsave(&domain->iommu_lock, flags); if (!test_and_set_bit(iommu->seq_id, &domain->iommu_bmp)) { domain->iommu_count++; - domain_update_iommu_coherency(domain); + domain_update_iommu_cap(domain); } spin_unlock_irqrestore(&domain->iommu_lock, flags); return 0; @@ -2820,7 +2848,7 @@ static void vm_domain_remove_one_dev_info(struct dmar_domain *domain, spin_lock_irqsave(&domain->iommu_lock, tmp_flags); clear_bit(iommu->seq_id, &domain->iommu_bmp); domain->iommu_count--; - domain_update_iommu_coherency(domain); + domain_update_iommu_cap(domain); spin_unlock_irqrestore(&domain->iommu_lock, tmp_flags); } @@ -2848,13 +2876,13 @@ static void vm_domain_remove_all_dev_info(struct dmar_domain *domain) iommu_detach_dev(iommu, info->bus, info->devfn); /* clear this iommu in iommu_bmp, update iommu count - * and coherency + * and capabilities */ spin_lock_irqsave(&domain->iommu_lock, flags2); if (test_and_clear_bit(iommu->seq_id, &domain->iommu_bmp)) { domain->iommu_count--; - domain_update_iommu_coherency(domain); + domain_update_iommu_cap(domain); } spin_unlock_irqrestore(&domain->iommu_lock, flags2); |