6.6-stable review patch. If anyone has any objections, please let me know.
------------------
From: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx>
commit ea315f98e5d6d3191b74beb0c3e5fc16081d517c upstream.
We want a fixed load CCS balancing consisting in all slices
sharing one single user engine. For this reason do not create the
intel_engine_cs structure with its dedicated command streamer for
CCS slices beyond the first.
Fixes: d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Signed-off-by: Andi Shyti <andi.shyti@xxxxxxxxxxxxxxx>
Cc: Chris Wilson <chris.p.wilson@xxxxxxxxxxxxxxx>
Cc: Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>
Cc: Matt Roper <matthew.d.roper@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v6.2+
Acked-by: Michal Mrozek <michal.mrozek@xxxxxxxxx>
Reviewed-by: Matt Roper <matthew.d.roper@xxxxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/20240328073409.674098-3-andi.shyti@xxxxxxxxxxxxxxx
(cherry picked from commit c7a5aa4e57f88470313a8277eb299b221b86e3b1)
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/gpu/drm/i915/gt/intel_engine_cs.c | 17 +++++++++++++++++
1 file changed, 17 insertions(+)
--- a/drivers/gpu/drm/i915/gt/intel_engine_cs.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_cs.c
@@ -912,6 +912,23 @@ static intel_engine_mask_t init_engine_m
info->engine_mask &= ~BIT(GSC0);
}
+ /*
+ * Do not create the command streamer for CCS slices beyond the first.
+ * All the workload submitted to the first engine will be shared among
+ * all the slices.
+ *
+ * Once the user will be allowed to customize the CCS mode, then this
+ * check needs to be removed.
+ */
+ if (IS_DG2(gt->i915)) {
+ u8 first_ccs = __ffs(CCS_MASK(gt));
+
+ /* Mask off all the CCS engine */
+ info->engine_mask &= ~GENMASK(CCS3, CCS0);
+ /* Put back in the first CCS engine */
+ info->engine_mask |= BIT(_CCS(first_ccs));
+ }
+
return info->engine_mask;
}
