[Nouveau] [PATCH v4] pmu/gk20a: PMU boot support

[Alexandre Courbot]

>>>> - What about signature files that are required for secure boot?
>>> As with above, if it's possible to ship them in a single file with the
>>> ucode that it belongs to, that'd be ideal.  It's not a huge deal
>>> though.
>>
>> So here we actually have several files - it is kind of a mess
>> actually. However I could probably merge them into a single netlist
>> file like we did for the GPC/FE CS code.
> If that's possible, that'd be great.

I am still trying to figure out internally what makes the most sense,
but this is one of the open options. Another is to use another
packaging format that is already supported by upstream, or just to lay
all firmware binaries as-is, one file per firmware (hopefully properly
organized in nvidia/<chip>/). It's quite impressive how much
bikeshedding we can do on simple questions. :) Are you aware of a
"best practice" for upstream firmwares?

>> Right now my main concern is to get secure boot support in, and the
>> shortest path seems to be to not care about ABI compatibility between
>> Nouveau and NV firmwares (at least for PMU). Basically I am hoping
>> that you will agree to proceed this way in a first time. ^_^
> If it's really that urgent, my suggestion is to submit the patches as
> you did previously, keeping them confined to GK20A/GM20B, and I'll do
> something nicer to support boards in general.
>
> Frankly, I'd have had secure boot support in the driver already had
> NVIDIA played things a little differently...  Going forward, I'd like
> to see NVIDIA not treating the Tegra parts of nouveau as a little
> black box where anything goes and things are different from the rest
> of the driver.  The chips operate, for the most part, identically to
> their big siblings...

I agree that's not optimal, and I apologize for that. The main reason
is that Tegra and dGPU are working mostly separately within NVIDIA,
despite sharing the same driver. In this case I agree it does not make
much sense, as this code is not Tegra-specific.

But on the other hand, we need to start with a chip. It just happens
that for secure boot we are starting with Tegra, but this work should
be leverageable for dGPUs and I don't expect it to take too much
effort. Of course if we were good citizens we would do it ourselves
while we are at it. :/