[PATCH v2 3/8] dt-bindings: media: mediatek,jpeg: Relax IOMMU max item count

Matthias Brugger matthias.bgg at gmail.com
Wed Oct 2 06:12:38 PDT 2024



On 02/10/2024 08:16, Krzysztof Kozlowski wrote:
> On Tue, Oct 01, 2024 at 07:27:21PM +0800, Fei Shao wrote:
>> On MediaTek platforms with Multimedia MMU (M4U), a multimedia hardware
>> can be assigned with a local arbiter (LARB) which has a maximum of 32
>> ports for MediaTek's IOMMU infrastructure. That means there can be at
>> most 32 items in the iommus property in theory.
>>
>> Instead of relaxing the max item count every time a newly introduced
>> device tree hits the limit, bump the number to 32 as an one-time effort.
>>
>> On the other hand, all existing and foreseeable JPEG decoder nodes at
>> this point have at least 2 IOMMUs, so set minItems to 2 accordingly.
>>
>> Signed-off-by: Fei Shao <fshao at chromium.org>
>> ---
>> It's not in the upstream tree yet, but the upcoming MT8188 DT will have
>> 6 IOMMUs in its JPEG decoder. This patch is to pave the way for that.
>>
>> Changes in v2:
>> New patch.
>>
> 
> I do not see any user of this in this patchset.
> 

I'm not sure I understand you: the binding describes the hardware. If it can 
have up to 32 ports, then this should be reflected in the binding.

Regards,
Matthias




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