Re: [PATCH v2 5/6] gpu: nova-core: skip the IFR header if present

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

On Thu Apr 16, 2026 at 9:00 AM JST, Timur Tabi wrote:
> On Wed, 2026-04-15 at 21:08 +0000, Timur Tabi wrote:
>> The second two I made up, so they can't be imported.  NV_PBUS_IFR_FMT_FIXED0_SIGNATURE_VALUE comes
>> from dev_bus.h as you said, but NV_ROM_DIRECTORY_IDENTIFIER comes from kernel_gsp_vbios_tu102.c,
>> so
>> I don't think it can be imported either.
>> 
>> Also, what tree is your DIFF for? 
>
> I've given this some thought, and I don't think it's the right approach.  It has the side effect of
> having vbios.rs depend on constants that are defined in GSP version-specific header files.  It's
> also a convoluted way to add just one constant.
>
> So I think I will just keep
>
> /// IFR signature: ASCII "NVGI" as a little-endian u32.
> const NV_PBUS_IFR_FMT_FIXED0_SIGNATURE_VALUE: u32 = 0x4947564E;
>
> in vbios.rs

Yeah, thinking again about it, these values are from the VBIOS - thus
they are fixed irrespective of the GSP firmware version. We use the
bindings to shield us against subtle changes between GSP firmware
releases, but that's not going to happen here.

Getting our values from the bindings would also extend them from being
pure-GSP to covering other stuff, which is something we should try to
avoid.