[Intel-xe] [RFC v2 0/2] drm/xe/pvc: Enable fixed CCS mode

[Summers, Stuart]

On Wed, 2023-11-01 at 16:57 -0700, Niranjana Vishwanathapura wrote:
> Allow static assignment of compute slices to a user selected
> number of compute engines. Add a per-tile 'ccs_mode' sysfs
> interface for user selection. By default assign all compute
> resources to the first available compute engine. User must
> ensure the tile is idle while changing the ccs mode as this
> causes a tile reset. User must also ensure that there are no

How will the user know that the device is idle when the KMD/GuC are
responsible for submission management between processes? This is the
reason we went through the context creation interface in i915 rather
than having a user-specific interface like sysfs or ioctl.

Thanks,
Stuart

> open exec queues while changing the ccs mode. Also, error will
> be returned for exec queue creation with disabled ccs engines. 
> 
> Support this mode for PVC which can be extended to other
> platforms in future.
> 
> IGT: https://patchwork.freedesktop.org/series/125873/
> 
> v2: Fixed issue with HW config, ensure no exec queue is created
>     with disabled CCS engines.
> 
> Signed-off-by: Niranjana Vishwanathapura
> <niranjana.vishwanathapura at intel.com>
> 
> Niranjana Vishwanathapura (2):
>   drm/xe: Enable Fixed CCS mode setting
>   drm/xe: Prevent exec_queues creation on diabled CCS engines
> 
>  drivers/gpu/drm/xe/Makefile          |  1 +
>  drivers/gpu/drm/xe/regs/xe_gt_regs.h | 14 +++++
>  drivers/gpu/drm/xe/xe_device.c       |  1 +
>  drivers/gpu/drm/xe/xe_device_types.h |  9 ++++
>  drivers/gpu/drm/xe/xe_exec_queue.c   | 45 +++++++++++++++-
>  drivers/gpu/drm/xe/xe_gt.c           | 27 ++++++++--
>  drivers/gpu/drm/xe/xe_gt.h           |  2 +
>  drivers/gpu/drm/xe/xe_gt_ccs_mode.c  | 79
> ++++++++++++++++++++++++++++
>  drivers/gpu/drm/xe/xe_gt_ccs_mode.h  | 22 ++++++++
>  drivers/gpu/drm/xe/xe_gt_types.h     | 16 ++++++
>  drivers/gpu/drm/xe/xe_guc_ads.c      |  3 ++
>  drivers/gpu/drm/xe/xe_hw_engine.c    | 14 +++++
>  drivers/gpu/drm/xe/xe_tile_sysfs.c   | 62 ++++++++++++++++++++++
>  13 files changed, 288 insertions(+), 7 deletions(-)
>  create mode 100644 drivers/gpu/drm/xe/xe_gt_ccs_mode.c
>  create mode 100644 drivers/gpu/drm/xe/xe_gt_ccs_mode.h
>