Export IOMMU internals in DebugFS

modulename: iommu-debugfs.ko

configname: CONFIG_IOMMU_DEBUGFS

Linux Kernel Configuration
└─>Device Drivers
└─>IOMMU Hardware Support
└─>Export IOMMU internals in DebugFS
In linux kernel since version 4.2 (release Date: 2015-08-30)  
Allows exposure of IOMMU device internals. This option enables
the use of debugfs by IOMMU drivers as required. Devices can,
at initialization time, cause the IOMMU code to create a top-level
debug/iommu directory, and then populate a subdirectory with
entries as required.

source code: