drm/i915/xehp: Drop GETPARAM lookups of I915_PARAM_[SUB]SLICE_MASK
authorMatt Roper <matthew.d.roper@intel.com>
Wed, 1 Jun 2022 15:07:21 +0000 (08:07 -0700)
committerMatt Roper <matthew.d.roper@intel.com>
Thu, 2 Jun 2022 14:19:11 +0000 (07:19 -0700)
commitaa2bdc4843f5871e6c68fbec5e10c0dbaf10ff91
tree3439bbed1a98b454f15f42cba2726e7f0fae77bb
parent935a3c66eb9b66426d4be9b54666c77dbe7c32eb
drm/i915/xehp: Drop GETPARAM lookups of I915_PARAM_[SUB]SLICE_MASK

Slice/subslice/EU information should be obtained via the topology
queries provided by the I915_QUERY interface; let's turn off support for
the old GETPARAM lookups on Xe_HP and beyond where we can't return
meaningful values.

The slice mask lookup is meaningless since Xe_HP doesn't support
traditional slices (and we make no attempt to return the various new
units like gslices, cslices, mslices, etc.) here.

The subslice mask lookup is even more problematic; given the distinct
masks for geometry vs compute purposes, the combined mask returned here
is likely not what userspace would want to act upon anyway.  The value
is also limited to 32-bits by the nature of the GETPARAM ioctl which is
sufficient for the initial Xe_HP platforms, but is unable to convey the
larger masks that will be needed on other upcoming platforms.  Finally,
the value returned here becomes even less meaningful when used on
multi-tile platforms where each tile will have its own masks.

Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> # mesa
Reviewed-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220601150725.521468-3-matthew.d.roper@intel.com
drivers/gpu/drm/i915/i915_getparam.c