iommu: Add event tracing feature to iommu

Add tracing feature to iommu to report various iommu events. Classes
iommu_group, iommu_device, and iommu_map_unmap are defined.

iommu_group class events can be enabled to trigger when devices get added
to and removed from an iommu group. Trace information includes iommu group
id and device name.

iommu:add_device_to_group
iommu:remove_device_from_group

iommu_device class events can be enabled to trigger when devices are attached
to and detached from a domain. Trace information includes device name.

iommu:attach_device_to_domain
iommu:detach_device_from_domain

iommu_map_unmap class events can be enabled to trigger when iommu map and
unmap iommu ops. Trace information includes iova, physical address (map event
only), and size.

iommu:map
iommu:unmap

Signed-off-by: Shuah Khan <shuah.kh@samsung.com>
Signed-off-by: Joerg Roedel <joro@8bytes.org>
diff --git a/drivers/iommu/Makefile b/drivers/iommu/Makefile
index 14c1f47..5d58bf1 100644
--- a/drivers/iommu/Makefile
+++ b/drivers/iommu/Makefile
@@ -1,4 +1,5 @@
 obj-$(CONFIG_IOMMU_API) += iommu.o
+obj-$(CONFIG_IOMMU_API) += iommu-traces.o
 obj-$(CONFIG_OF_IOMMU)	+= of_iommu.o
 obj-$(CONFIG_MSM_IOMMU) += msm_iommu.o msm_iommu_dev.o
 obj-$(CONFIG_AMD_IOMMU) += amd_iommu.o amd_iommu_init.o