[PATCH 1/3] iommu: Print default domain type on boot

[Joerg Roedel]

From: Joerg Roedel <jroe...@suse.de>

Introduce a subsys_initcall for IOMMU code and use it to
print the default domain type at boot.

Signed-off-by: Joerg Roedel <jroe...@suse.de>
---
 drivers/iommu/iommu.c | 30 +++++++++++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index 0c674d80c37f..b57ce00c1310 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -80,12 +80,40 @@ struct iommu_group_attribute iommu_group_attr_##_name =     
        \
 static LIST_HEAD(iommu_device_list);
 static DEFINE_SPINLOCK(iommu_device_lock);
 
+/*
+ * Use a function instead of an array here because the domain-type is a
+ * bit-field, so an array would waste memory.
+ */
+static const char *iommu_domain_type_str(unsigned int t)
+{
+       switch (t) {
+               case IOMMU_DOMAIN_BLOCKED:
+                       return "Blocked";
+               case IOMMU_DOMAIN_IDENTITY:
+                       return "Passthrough";
+               case IOMMU_DOMAIN_UNMANAGED:
+                       return "Unmanaged";
+               case IOMMU_DOMAIN_DMA:
+                       return "Translated";
+               default:
+                       return "Unknown";
+       }
+}
+
+static int __init iommu_subsys_init(void)
+{
+       pr_info("Default domain type: %s\n",
+               iommu_domain_type_str(iommu_def_domain_type));
+
+       return 0;
+}
+subsys_initcall(iommu_subsys_init);
+
 int iommu_device_register(struct iommu_device *iommu)
 {
        spin_lock(&iommu_device_lock);
        list_add_tail(&iommu->list, &iommu_device_list);
        spin_unlock(&iommu_device_lock);
-
        return 0;
 }
 
-- 
2.17.1