Re: [PATCH v5 3/4] gpu: nova-core: avoid probing non-display/compute PCI functions

[John Hubbard <jhubbard@nvidia.com>]

On 8/21/25 3:52 AM, Danilo Krummrich wrote:
> On Thu Aug 21, 2025 at 6:42 AM CEST, John Hubbard wrote:
>> NovaCore has so far been too imprecise about figuring out if .probe()
>> has found a supported PCI PF (Physical Function). By that I mean:
>> .probe() sets up BAR0 (which involves a lot of very careful devres and
>> Device<Bound> details behind the scenes). And then if it is dealing with
>> a non-supported device such as the .1 audio PF on many GPUs, it fails
>> out due to an unexpected BAR0 size. We have been fortunate that the BAR0
>> sizes are different.
>>
>> Really, we should be filtering on PCI class ID instead. These days I
>> think we can confidently pick out Nova's supported PF's via PCI class
>> ID. And if not, then we'll revisit.
>>
>> The approach here is to filter on "Display VGA" or "Display 3D", which
>> is how PCI class IDs express "this is a modern GPU's PF".
>>
>> Cc: Danilo Krummrich <dakr@kernel.org>
>> Cc: Alexandre Courbot <acourbot@nvidia.com>
>> Cc: Elle Rhumsaa <elle@weathered-steel.dev>
>> Signed-off-by: John Hubbard <jhubbard@nvidia.com>
>> ---
>>   drivers/gpu/nova-core/driver.rs | 33 ++++++++++++++++++++++++++++-----
>>   rust/kernel/pci.rs              | 21 +++++++++++++++++++++
> 
> Can you please split this one up in two patches?

Sure.

> 
>>   2 files changed, 49 insertions(+), 5 deletions(-)

thanks,
-- 
John Hubbard