Re: [PATCH v4 3/3] of: Respect #{iommu,msi}-cells in maps
From: Vijayanand Jitta
Date: Sun Jan 18 2026 - 13:15:50 EST
On 1/7/2026 4:30 PM, Konrad Dybcio wrote:
> On 1/7/26 6:31 AM, Vijayanand Jitta wrote:
>>
>>
>> On 12/31/2025 5:12 PM, Vijayanand Jitta wrote:
>>> From: Robin Murphy <robin.murphy@xxxxxxx>
>>>
>>> So far our parsing of {iommu,msi}-map properites has always blindly
>>> asusmed that the output specifiers will always have exactly 1 cell.
>>> This typically does happen to be the case, but is not actually enforced
>>> (and the PCI msi-map binding even explicitly states support for 0 or 1
>>> cells) - as a result we've now ended up with dodgy DTs out in the field
>>> which depend on this behaviour to map a 1-cell specifier for a 2-cell
>>> provider, despite that being bogus per the bindings themselves.
>>>
>>> Since there is some potential use in being able to map at least single
>>> input IDs to multi-cell output specifiers (and properly support 0-cell
>>> outputs as well), add support for properly parsing and using the target
>>> nodes' #cells values, albeit with the unfortunate complication of still
>>> having to work around expectations of the old behaviour too.
>>>
>>> Since there are multi-cell output specifiers, the callers of of_map_id()
>>> may need to get the exact cell output value for further processing.
>>> Added support for that part --charan
>>>
>>> Signed-off-by: Robin Murphy <robin.murphy@xxxxxxx>
>>> Signed-off-by: Vijayanand Jitta <vijayanand.jitta@xxxxxxxxxxxxxxxx>
>>> ---
>
> [...]
>
>> Rob,
>>
>> Gentle ping, could you please let me know if the latest patchset looks good enough
>> to be considered for the next merge window?
>
> You have an outstanding build warning:
>
> <202601062128.BCmw1wNO-lkp@xxxxxxxxx>
>
> Konrad
Thanks, I have fixed those and sent out V5. Please review.
Thanks,
Vijay