Re: [PATCH v8 25/25] gpu: nova-core: mm: Add PRAMIN aperture self-tests

[Alexandre Courbot]

On Tue Mar 3, 2026 at 5:11 AM JST, Joel Fernandes wrote:
> On Mon, Mar 02, 2026 at 09:04:07PM +0900, Alexandre Courbot wrote:
>> > +    // PRAMIN support is only for MMU v2 for now (Turing/Ampere/Ada).
>> > +    if mmu_version != MmuVersion::V2 {
>>
>> Why is that? I thought PRAMIN was also working on Hopper+. Isn't it
>> orthogonal to the kind of MMU used?
>
> The PRAMIN aperture window register changed on Hopper+: pre-Hopper uses
> NV_PBUS_BAR0_WINDOW while Hopper+ uses NV_XAL_EP_BAR0_WINDOW. Our
> current code only programs the former, so we'd need a HAL to support
> both. For now, V2-only is the safe choice. I've updated the comment to
> explain this.

I see, but then it seems that the correct check would be against the `Chipset`, not the
version of the page table format? I understand the two are linked
transitively, but they are in practice different engines.