calculate agaw for each iommu

"SAGAW" capability may be different across iommus. Use a default agaw, but if default agaw is not supported in some iommus, choose a less supported agaw.

Signed-off-by: Weidong Han <weidong.han@intel.com>
Signed-off-by: Joerg Roedel <joerg.roedel@amd.com>

2 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/dma_remapping.h b/include/linux/dma_remapping.h
index 7799a85614c1..136f170cecc2 100644
--- a/include/linux/dma_remapping.h
+++ b/include/linux/dma_remapping.h
@@ -17,6 +17,7 @@ struct dmar_domain;
 struct root_entry;
 
 extern void free_dmar_iommu(struct intel_iommu *iommu);
+extern int iommu_calculate_agaw(struct intel_iommu *iommu);
 
 extern int dmar_disabled;
 
diff --git a/include/linux/intel-iommu.h b/include/linux/intel-iommu.h
index 1bff7bf1bc2c..06349fd5871b 100644
--- a/include/linux/intel-iommu.h
+++ b/include/linux/intel-iommu.h
@@ -290,6 +290,7 @@ struct intel_iommu {
         u32             gcmd; /* Holds TE, EAFL. Don't need SRTP, SFL, WBF */
         spinlock_t      register_lock; /* protect register handling */
         int             seq_id; /* sequence id of the iommu */
+        int             agaw; /* agaw of this iommu */
 
 #ifdef CONFIG_DMAR
         unsigned long   *domain_ids; /* bitmap of domains */