drm/nouveau: Fix drm_driver struct/nouveau.atomic parameter handling

Browse source

The way we handled the nouveau.atomic module parameter before was fairly
broken, and had a number of issues:

- It was only ever actually parsed in the case of PCI devices.
- When nouveau.atomic was enabled, it would add the cap for atomic
  modesetting to the global driver_pci structure. This meant that if one
  GPU on a system supported atomic and another didn't, it would still get
  enabled for both.

Looking into this exposed further silliness in the way that we actually
handle the drm_driver struct. We have one global structure for platform
devices, and another for PCI devices - both of which are literally
identical.

So before we start preparing to enable atomic modesetting by default, let's
fix this. Instead of sharing driver_pci and driver_platform, we instead
create driver_legacy_kms and driver_atomic_kms, each of which is identical
except for the DRIVER_ATOMIC capabilities flag, and then assign either
depending on the nouveau_atomic module parameter.

Doing this is also preferable, as the next step for enabling atomic
modesetting by default will be ensuring that we don't enable it for legacy
devices that still don't support it. This requires only checking the atomic
modesetting module parameter after the NVKM device is ready, as this allows
us to check the GPU family that nouveau is running on.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Dave Airlie <airlied@redhat.com>
Link: https://patch.msgid.link/20260813204803.2097176-4-lyude@redhat.com

...

This commit is contained in:

Lyude Paul 2026-08-13 16:46:49 -04:00

parent dfed5a2bb5

commit 830b2e55df

1 changed files with 58 additions and 42 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

98

drivers/gpu/drm/nouveau/nouveau_drm.c

View file