[PATCH 0/5] Add debugfs support for ARM SMMUv3

[Qinxin Xia]

On 2026/5/27 08:07:17, Nicolin Chen <nicolinc at nvidia.com> wrote:
> On Wed, May 20, 2026 at 02:37:06PM +0800, Qinxin Xia wrote:
>> Add a comprehensive debugfs framework to the ARM SMMUv3 driver,
>> providing visibility into internal hardware state for debugging
>> and performance analysis. The debugfs entries are organized under
>> /sys/kernel/debug/iommu/arm_smmu_v3/, with per-SMMU instance directories
>> and per-device stream table entries.
>>
>> Each SMMU instance provides:
>> - capabilities – static SMMU features and queue sizes.
>> - registers – SMMU key registers.
>> - stream_table/ – a directory per device with subdirectories per Stream ID.
>>
>> Each Stream ID subdirectory contains:
>> - ste – the Stream Table Entry in decoded and raw format.
>> - cd – all valid Context Descriptors (Stage 1 translation tables) associated with the device.
>> - a symlink named with the device's BDF/name pointing to its sysfs directory for easy navigation.
>>
>> /sys/kernel/debug/iommu/arm_smmu_v3/smmu0/stream_table/
>>      ├── <sid>/
>>      │   ├── ste
>>      │   ├── cd
>>      │   └── <dev_name>
>>
>> Changes since RFCv2:
>>    Address review comments from Nicolin Chen, kernel test robot, and Sashiko
>>    automated review:
> 
> This seems to reuse the same message ID as RFCv2's?
> 
> So, it ended up with attaching to RFCv2, on my side (mutt).
> 
> Sashiko also failed to review against the new patches:
> https://sashiko.dev/#/patchset/20260328101706.3448655-1-xiaqinxin%40huawei.com
> 
> Nicolin
> 

Sorry for the late reply – I've been juggling a few things and missed 
this update earlier.

I'll fold all the fixes into the next spin. Expect v3 soon.:-)

-- 
Thanks,
Qinxin