Documentation/ABI/testing/debugfs-amd-iommu

Source file repositories/reference/linux-study-clean/Documentation/ABI/testing/debugfs-amd-iommu

File Facts

System: Linux kernel
Corpus path: Documentation/ABI/testing/debugfs-amd-iommu
Extension: [no extension]
Size: 3937 bytes
Lines: 132
Domain: Support Tooling And Documentation
Bucket: Documentation
Inferred role: Support Tooling And Documentation: Documentation
Status: atlas-only

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

No C-style include directives detected by the generator.

Detected Declarations

No top-level syscall, struct, function, initcall, or export declaration detected by the generator.

Annotated Snippet

What:		/sys/kernel/debug/iommu/amd/iommu<x>/mmio
Date:		January 2025
Contact:	Dheeraj Kumar Srivastava <dheerajkumar.srivastava@amd.com>
Description:
		This file provides read/write access for user input. Users specify the
		MMIO register offset for iommu<x>, and the file outputs the corresponding
		MMIO register value of iommu<x>

		Example::

		  $ echo "0x18" > /sys/kernel/debug/iommu/amd/iommu00/mmio
		  $ cat /sys/kernel/debug/iommu/amd/iommu00/mmio

		Output::

		  Offset:0x18 Value:0x000c22000003f48d

What:		/sys/kernel/debug/iommu/amd/iommu<x>/capability
Date:		January 2025
Contact:	Dheeraj Kumar Srivastava <dheerajkumar.srivastava@amd.com>
Description:
		This file provides read/write access for user input. Users specify the
		capability register offset for iommu<x>, and the file outputs the
		corresponding capability register value of iommu<x>.

		Example::

		  $ echo "0x10" > /sys/kernel/debug/iommu/amd/iommu00/capability
		  $ cat /sys/kernel/debug/iommu/amd/iommu00/capability

		Output::

		  Offset:0x10 Value:0x00203040

What:		/sys/kernel/debug/iommu/amd/iommu<x>/cmdbuf
Date:		January 2025
Contact:	Dheeraj Kumar Srivastava <dheerajkumar.srivastava@amd.com>
Description:
		This file is a read-only output file containing iommu<x> command
		buffer entries.

		Examples::

		  $ cat /sys/kernel/debug/iommu/amd/iommu<x>/cmdbuf

		Output::

		  CMD Buffer Head Offset:339 Tail Offset:339
		    0: 00835001 10000001 00003c00 00000000
		    1: 00000000 30000005 fffff003 7fffffff
		    2: 00835001 10000001 00003c01 00000000
		    3: 00000000 30000005 fffff003 7fffffff
		    4: 00835001 10000001 00003c02 00000000
		    5: 00000000 30000005 fffff003 7fffffff
		    6: 00835001 10000001 00003c03 00000000
		    7: 00000000 30000005 fffff003 7fffffff
		    8: 00835001 10000001 00003c04 00000000
		    9: 00000000 30000005 fffff003 7fffffff
		   10: 00835001 10000001 00003c05 00000000
		   11: 00000000 30000005 fffff003 7fffffff
		  [...]

What:		/sys/kernel/debug/iommu/amd/devid
Date:		January 2025
Contact:	Dheeraj Kumar Srivastava <dheerajkumar.srivastava@amd.com>
Description:
		This file provides read/write access for user input. Users specify the
		device ID, which can be used to dump IOMMU data structures such as the
		interrupt remapping table and device table.

Annotation

Atlas domain: Support Tooling And Documentation / Documentation.
Implementation status: atlas-only.

Implementation Notes

This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.