[PATCH v8 1/3] iommu/arm-smmu: add NVIDIA implementation for dual ARM MMU-500 usage

Krishna Reddy vdumpa at nvidia.com
Wed Jul 1 15:12:58 EDT 2020


>Yeah, I realised later last night that this probably originated from forking the whole driver downstream. But even then you could have treated the other one as a separate nsmmu with a single instance ;)

True, But the initial nvidia implementation had limitation that it can only handle one instance of usage. With your implementation hooks design, it should be able to handle multiple instances of usage now.

>Since it does add a bit of confusion to the code and comments, let's just keep things simple. I do like Jon's suggestion of actually enforcing that the number of "reg" regions exactly matches the number expected for the given compatible - I guess for now that means just hard-coding 2 and hoping the hardware folks don't cook up any more of these...

For T194, reg can just be forced to 2. No future plan to use more than two MMU-500s together as of now. 

-KR 


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