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Subject: Re: [PATCH RFC v1 01/11] uapi/virtio-iommu: Add page request grp-id
 and flags information
To:     Jean-Philippe Brucker <jean-philippe@linaro.org>
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From:   Vivek Kumar Gautam <vivek.gautam@arm.com>
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Date:   Thu, 30 Sep 2021 16:27:15 +0530
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On 9/30/21 2:19 PM, Jean-Philippe Brucker wrote:
> On Thu, Sep 30, 2021 at 10:26:35AM +0530, Vivek Kumar Gautam wrote:
>>> I'm not sure why we made it 32-bit in Linux UAPI, it's a little wasteful.
>>> PCIe PRGI is 9-bits and SMMU STAG is 16-bits. Since the scope of the grpid
>>> is the endpoint, 16-bit means 64k in-flight faults per endpoint, which
>>> seems more than enough.
>>
>> Right, I will update this to 16-bits field. It won't be okay to update the
>> iommu uAPI now, right?
> 
> Since there is no UAPI transport for the fault request/response at the
> moment, it should be possible to update it.

Righty! I will add a patch for that too then.


Thanks & regards

Vivek