iommu/amd: Don't initialize IOMMUv2 resources when not required
[pandora-kernel.git] / drivers / iommu / amd_iommu_v2.c
index 8add9f1..036fe9b 100644 (file)
@@ -921,7 +921,16 @@ static int __init amd_iommu_v2_init(void)
        size_t state_table_size;
        int ret;
 
-       pr_info("AMD IOMMUv2 driver by Joerg Roedel <joerg.roedel@amd.com>");
+       pr_info("AMD IOMMUv2 driver by Joerg Roedel <joerg.roedel@amd.com>\n");
+
+       if (!amd_iommu_v2_supported()) {
+               pr_info("AMD IOMMUv2 functionality not available on this sytem\n");
+               /*
+                * Load anyway to provide the symbols to other modules
+                * which may use AMD IOMMUv2 optionally.
+                */
+               return 0;
+       }
 
        spin_lock_init(&state_lock);
 
@@ -961,6 +970,9 @@ static void __exit amd_iommu_v2_exit(void)
        size_t state_table_size;
        int i;
 
+       if (!amd_iommu_v2_supported())
+               return;
+
        profile_event_unregister(PROFILE_TASK_EXIT, &profile_nb);
        amd_iommu_unregister_ppr_notifier(&ppr_nb);