From 5a9d0ab8fb97f2a0a4cc8c85e5f8d1698a9f52f7 Mon Sep 17 00:00:00 2001
From: Matt Roper <matthew.d.roper@intel.com>
Date: Wed, 1 Jun 2022 08:07:21 -0700
Subject: drm/i915/xehp: Drop GETPARAM lookups of I915_PARAM_[SUB]SLICE_MASK
Git-commit: aa2bdc4843f5871e6c68fbec5e10c0dbaf10ff91
Patch-mainline: v6.0-rc1
References: jsc#PED-1166 jsc#PED-1168 jsc#PED-1170 jsc#PED-1218 jsc#PED-1220 jsc#PED-1222 jsc#PED-1223 jsc#PED-1225 jsc#PED-2849
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
Acked-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/i915/i915_getparam.c | 8 ++++++++
1 file changed, 8 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_getparam.c b/drivers/gpu/drm/i915/i915_getparam.c
index c12a0adefda5..ac9767c56619 100644
--- a/drivers/gpu/drm/i915/i915_getparam.c
+++ b/drivers/gpu/drm/i915/i915_getparam.c
@@ -148,11 +148,19 @@ int i915_getparam_ioctl(struct drm_device *dev, void *data,
value = intel_engines_has_context_isolation(i915);
break;
case I915_PARAM_SLICE_MASK:
+ /* Not supported from Xe_HP onward; use topology queries */
+ if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50))
+ return -EINVAL;
+
value = sseu->slice_mask;
if (!value)
return -ENODEV;
break;
case I915_PARAM_SUBSLICE_MASK:
+ /* Not supported from Xe_HP onward; use topology queries */
+ if (GRAPHICS_VER_FULL(i915) >= IP_VER(12, 50))
+ return -EINVAL;
+
/* Only copy bits from the first slice */
memcpy(&value, sseu->subslice_mask,
min(sseu->ss_stride, (u8)sizeof(value)));
--
2.38.1