Re: [Nouveau] [RFC 0/4] Implement full clockgating for Kepler1 and 2

[Mikko Perttunen]

On 01/16/2018 12:06 AM, Lyude Paul wrote:
> It's here! After a lot of investigation, rewrites, and traces, I present
> the patch series to implement all known levels of clockgating for
> Kepler1 and Kepler2 GPUs.
>
> Starting with Fermi GPUs (this is probably present on earlier GPUs as
> well, but with a far less easy to manage interface), nvidia added two
> clockgating levels that are handled mostly in firmware (with the
> exception of course, of the driver initially programming all of the
> register values containing engine delays and that stuff):
>    - CG_CTRL - Main register for enabling/disabling clockgating for
>      engines and hw blocks
>    - BLCG - "Block-level clockgating", a deeper level of clockgating
> Starting with kepler2 as well, nvidia also introduced:
>    - SLCG - "??? clockgating" even deeper level of clockgating

FWIW, SLCG stands for "second level clock gating".

Cheers,
Mikko