Re: [PATCH 00/16] nova-core: run FWSEC-FRTS to perform first stage of GSP initialization

["Alexandre Courbot" <acourbot@nvidia.com>]

Hi Danilo,

On Tue Apr 22, 2025 at 5:40 PM JST, Danilo Krummrich wrote:
> On Sun, Apr 20, 2025 at 09:19:32PM +0900, Alexandre Courbot wrote:
>> Hi everyone,
>> 
>> This series is a continuation of my previous RFCs [1] to complete the
>> first step of GSP booting (running the FWSEC-FRTS firmware extracted
>> from the BIOS) on Ampere devices. While it is still far from bringing
>> the GPU into a state where it can do anything useful, it sets up the
>> basic layout of the driver upon which we can build in order to continue
>> with the next steps of GSP booting, as well as supporting more chipsets.
>> 
>> Upon successful probe, the driver will display the range of the WPR2
>> region constructed by FWSEC-FRTS:
>> 
>>   [   95.436000] NovaCore 0000:01:00.0: WPR2: 0xffc00000-0xffce0000
>>   [   95.436002] NovaCore 0000:01:00.0: GPU instance built
>> 
>> This code is based on nova-next with the try_access_with patch [2].
>
> Please make sure to compile with CLIPPY=1, the series has quite some clippy
> warnings.

Indeed, I just tried and it wasn't pretty - sorry for the omission.

>
> I also noticed that there are a lot of compiler warnings about unreachable pub
> fields with rustc 1.78, whereas with the latest stable compiler there are none.
>
> I'm not exactly sure why that is (and I haven't looked further), but the
> corresponding fields indeed seem to have unnecessary pub visibility.

I'll try building with 1.78 and fix that.

>
>> There is still a bit of unsafe code where it is not desired, notably to
>> transmute byte slices into types that implement FromBytes - this is
>> because support for doing such transmute operations safely are not in
>> the kernel crate yet.
>
> I assume you refer to [3]? As long as we put a TODO and follow up once the
> series lands, that's fine for me.

Yes, that's the idea. Will do.

>
>> 
>> [1] https://lore.kernel.org/rust-for-linux/20250320-nova_timer-v3-0-79aa2ad25a79@nvidia.com/
>> [2] https://lore.kernel.org/rust-for-linux/20250411-try_with-v4-0-f470ac79e2e2@nvidia.com/
> [3] https://lore.kernel.org/lkml/20250330234039.29814-1-christiansantoslima21@gmail.com/