On 2/12/26 4:05 PM, Shameer Kolothum Thodi wrote:
>
>> -----Original Message-----
>> From: Eric Auger <[email protected]>
>> Sent: 12 February 2026 14:57
>> To: Shameer Kolothum Thodi <[email protected]>; Nicolin Chen
>> <[email protected]>
>> Cc: [email protected]; [email protected];
>> [email protected]; [email protected]; [email protected]; Nathan Chen
>> <[email protected]>; Matt Ochs <[email protected]>; Jiandi An
>> <[email protected]>; Jason Gunthorpe <[email protected]>;
>> [email protected]; [email protected];
>> [email protected]; Krishnakant Jaju <[email protected]>
>> Subject: Re: [PATCH v2 05/24] hw/arm/smmuv3-accel: Introduce CMDQV ops
>> interface
>>>> I had
>>>> the impression you reverted to a fallback impl. If there is
>>>> specialization, I still think ops are relevant. Eric
>>> There is no fallback implementation. So just to confirm, you are suggesting
>>> to remove the ops completely or just keep the ops for reset/init only?
>> Depends on the code to come next. If your reset and init really differs
>> between normal accel SMMU and vcmdq enhanced accel SMMU, to me it is
>> still relevant to have separate implementations in different callbacks.
> It is not an either/or case.
>
> The vCMDQ path does not replace the normal accelerated SMMU init/reset.
> Instead, it requires additional init/reset steps on top of the regular accel
> flow.
>
> if (accel)
> accel_init();
>
> if (accel && cmdqv)
> cmdqv_init();
>
> So the vCMDQ logic is an extension of the accelerated mode, not a fallback
> or alternative implementation.
>
> I think the later patches in the series make this clearer.
> Please let me know if you still feel the ops necessary.
Well I am concerned by the lack of scalability overall. Until now this
was more or less generic. Now we may have several implementors coming
with their own implementations of even a vendor will come with several
generations: today it is tegra241_cmdq, tomorrow we will have
tegraxxx_cmdq, arm_cmdq, ... How to get prepared for this mess? Will we
have a property for each one?
Eric
>
> Thanks,
> Shameer
