hv: init_iommu rework to enable IOMMU for partition mode ACRN

Current code enables IOMMU from init_iommu_vm0_domain which is called
from vm0/sos boot sequence. For partition mode VMs, this is not called as
VMs are numbered from 1.

This patch adds support to initialize root table pointer for each IOMMU
and enable all IOMMUs from init_iommu. Hence IOMMUs are enabled even
though ACRN does not boot vm0.

Tracked-On: #1246
Signed-off-by: Sainath Grandhi sainath.grandhi@intel.com

Author: Sainath Grandhi

hypervisor/arch/x86/vtd.c

@@ -662,9 +662,18 @@ static void dmar_set_root_table(struct dmar_drhd_rt *dmar_uint)
 {
 	uint64_t address;
 	uint32_t status;
+	void *root_table_vaddr = NULL;
 
 	spinlock_obtain(&(dmar_uint->lock));
 
+	root_table_vaddr = alloc_paging_struct();
+
+	if (root_table_vaddr != NULL) {
+		dmar_uint->root_table_addr = hva2hpa(root_table_vaddr);
+	} else {
+		ASSERT(false, "failed to allocate root table!");
+	}
+
 	/* Currently don't support extended root table */
 	address = dmar_uint->root_table_addr;
 
@@ -976,16 +985,7 @@ static int add_iommu_device(struct iommu_domain *domain, uint16_t segment,
 		return 1;
 	}
 
-	if (dmar_uint->root_table_addr == 0UL) {
-		void *root_table_vaddr = alloc_paging_struct();
-
-		if (root_table_vaddr != NULL) {
-			dmar_uint->root_table_addr = hva2hpa(root_table_vaddr);
-		} else {
-			ASSERT(false, "failed to allocate root table!");
-			return 1;
-		}
-	}
+	ASSERT(dmar_uint->root_table_addr != 0UL, "root table is not setup");
 
 	root_table =
 		(struct dmar_root_entry *)hpa2hva(dmar_uint->root_table_addr);
@@ -1280,6 +1280,8 @@ void init_iommu(void)
 	spinlock_init(&domain_lock);
 
 	register_hrhd_units();
+
+	enable_iommu();
 }
 
 void init_iommu_vm0_domain(struct vm *vm0)
@@ -1299,5 +1301,4 @@ void init_iommu_vm0_domain(struct vm *vm0)
 		}
 	}
 	cache_flush_invalidate_all();
-	enable_iommu();
 }