drm: nova: Add an info ioctl

Add an extensible info ioctl and use it to report basic GPU information.
One of the first things userspace needs to know about a GPU is its
architecture and which chip it is, so add those as the first fields in
the GPU info result. The chip identifier is opaque to userspace and is
only meaningful when compared against the values of enum
drm_nova_chipid.

The ioctl selects an information type by ID and writes the result through
a sized userspace buffer. The kernel truncates results to the supplied
size, allowing information structures to grow and new logical information
groups to be added without introducing new ioctls. Passing a NULL data
pointer returns the size of the requested information structure instead.

Suggested-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Alistair Popple <apopple@nvidia.com>
Link: https://patch.msgid.link/20260909064506.910162-8-apopple@nvidia.com
[ Avoid 'as' casts (add From<Chipset> for u32, From<Architecture> for
  u32 and use IntoSafeCast, IntoSafeCastArch); improve / simplify a few
  comments. - Danilo ]
Signed-off-by: Danilo Krummrich <dakr@kernel.org>

0 files changed, 0 insertions, 0 deletions