Re: [PATCH 1/3] gpu: nova-core: extract radix3 page table into its own module

[John Hubbard <jhubbard@nvidia.com>]

On 9/13/26 1:36 PM, Gary Guo wrote:
> On Sun Sep 13, 2026 at 8:54 PM BST, John Hubbard wrote:
>> In order to boot the GSP, nova-core loads the GSP firmware image into
>> system memory, and the GPU copies it into the framebuffer, the GPU's own
>> memory. The GPU finds the GSP firmware image's pages via "radix3", a
>> three-level page table of 4 KiB pages that the driver builds. Today the
>> table exists as fields within the GSP firmware wrapper, which is fine
>> because there is only one radix3 consumer.
>>
>> The upcoming r000 series[1], however, introduces a second radix3 caller:
>> the ucodes firmware image. That is because the GSP has been changed, so
>> that it automatically fetches the subset of ucodes that it requires,
>> thus reducing the size of the GSP image. This is a helpful change for
>> the firmware situation overall, but it will require nova-core to load
>> and provide ucodes, in much the same way that it was loading and
>> providing the GSP firmware image.
>>
>> Therefore, split out radix3 into its own module.
> 
> I find the name itself confusing if I don't read the docs. The radix in "radix3"
> is actually 512 (given 4 KiB page and 64-bit entry) and definitely not 3.
> 
> Perhaps name this "radixlv3" or something similar instead? Or perhaps call it
> GspPageTable?
Right, it's all about the number of levels, not the radix value, that's
true. Open RM loves "radix3" so much that I've become tone-deaf to the
name. :)

three_level_radix works, but is silly long for this.

Do we really care enough to insist on this, though? I'd be inclined
to ask to just leave it alone.

thanks,
-- 
John Hubbard