Re: [PATCH v3 0/8] Introduce debugfs support in IOMMU

[Suthikulpanit, Suravee]

On 2/6/2025 12:59 PM, Dheeraj Kumar Srivastava wrote:
> From: root <root@xxxxxxxxxxxxxxxxxxx>
>
> Introducing debugfs support in AMD/IOMMU driver that will allow
> userspace to dump below IOMMU information
> 1) MMIO and Capability register per IOMMU
> 2) Command buffer
> 3) Device table entry
> 4) Interrupt remapping table entry
>
> Analyzing contents of IOMMU data structures helps in understanding IOMMU
> capabilities and behavior and debug issues faster.
>
> 1. MMIO and Capability registers - Add support to dump MMIO and Capability
>     registers per IOMMU.
>
>     Example:
>     a. Write MMIO register offset to dump it
>        $ echo 0x18 > /sys/kernel/debug/iommu/amd/iommu00/mmio
>        $ cat /sys/kernel/debug/iommu/amd/iommu00/mmio
>
>        Output:
>        $ 0x0003f48d

Correction: Based on the documentation in patch 8/8, the output would be

	Offset:0x18 Value:0x0003f48d

>      b. Write capability register offset to dump it
>         $ echo 0x10 > /sys/kernel/debug/iommu/amd/iommu00/capability
>         $ cat /sys/kernel/debug/iommu/amd/iommu00/capability
>
>         Output:
>         $ 0x00203040

Correction: Based on the documentation in patch 8/8, the output would be

	Offset:0x10 Value:0x00203040

Suravee