Enable only one CCS engine by default with all the compute sices
allocated to it.
While generating the list of UABI engines to be exposed to the
user, exclude any additional CCS engines beyond the first
instance.
This change can be tested with igt i915_query.
Fixes: d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Requires: 97aba5e46038 ("drm/i915/gt: Refactor uabi engine class/instance list creation")
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+
---
drivers/gpu/drm/i915/gt/intel_engine_user.c | 11 ++++++++++
drivers/gpu/drm/i915/gt/intel_gt.c | 23 +++++++++++++++++++++
drivers/gpu/drm/i915/gt/intel_gt_regs.h | 5 +++++
3 files changed, 39 insertions(+)
diff --git a/drivers/gpu/drm/i915/gt/intel_engine_user.c b/drivers/gpu/drm/i915/gt/intel_engine_user.c
index 11cc06c0c785..9ef1c4ce252d 100644
--- a/drivers/gpu/drm/i915/gt/intel_engine_user.c
+++ b/drivers/gpu/drm/i915/gt/intel_engine_user.c
@@ -208,6 +208,7 @@ void intel_engines_driver_register(struct drm_i915_private *i915)
struct list_head *it, *next;
struct rb_node **p, *prev;
LIST_HEAD(engines);
+ u16 uabi_ccs = 0;
sort_engines(i915, &engines);
@@ -244,6 +245,16 @@ void intel_engines_driver_register(struct drm_i915_private *i915)
if (uabi_class > I915_LAST_UABI_ENGINE_CLASS)
continue;
+ /*
+ * The load is balanced among all the available compute
+ * slices. Expose only the first instance of the compute
+ * engine.
+ */
+ if (IS_DG2(i915) &&
+ uabi_class == I915_ENGINE_CLASS_COMPUTE &&
+ uabi_ccs++)
+ continue;
+
GEM_BUG_ON(uabi_class >=
ARRAY_SIZE(i915->engine_uabi_class_count));
i915->engine_uabi_class_count[uabi_class]++;
diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
index a425db5ed3a2..0aac97439552 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt.c
+++ b/drivers/gpu/drm/i915/gt/intel_gt.c
@@ -168,6 +168,26 @@ static void init_unused_rings(struct intel_gt *gt)
}
}
+static void intel_gt_apply_ccs_mode(struct intel_gt *gt)
+{
+ u32 mode;
+ int cslice;
+
+ if (!IS_DG2(gt->i915))
+ return;
+
+ /* Set '0' as a default CCS id to all the cslices */
+ mode = 0;
+
+ for (cslice = 0; cslice < hweight32(CCS_MASK(gt)); cslice++)
+ /* Write 0x7 if no CCS context dispatches to this cslice */
+ if (!(CCS_MASK(gt) & BIT(cslice)))
+ mode |= XEHP_CCS_MODE_CSLICE(cslice,
+ XEHP_CCS_MODE_CSLICE_MASK);
+
+ intel_uncore_write(gt->uncore, XEHP_CCS_MODE, mode);
+}
+
int intel_gt_init_hw(struct intel_gt *gt)
{
struct drm_i915_private *i915 = gt->i915;
@@ -195,6 +215,9 @@ int intel_gt_init_hw(struct intel_gt *gt)
intel_gt_init_swizzling(gt);
+ /* Configure CCS mode */
+ intel_gt_apply_ccs_mode(gt);
+
/*
* At least 830 can leave some of the unused rings
* "active" (ie. head != tail) after resume which
diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
index cf709f6c05ae..8224dd99c7d7 100644
--- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h
+++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
@@ -1480,6 +1480,11 @@
#define GEN12_RCU_MODE_CCS_ENABLE REG_BIT(0)
#define XEHP_RCU_MODE_FIXED_SLICE_CCS_MODE REG_BIT(1)
+#define XEHP_CCS_MODE _MMIO(0x14804)
+#define XEHP_CCS_MODE_CSLICE_MASK REG_GENMASK(2, 0) /* CCS0-3 + rsvd */
+#define XEHP_CCS_MODE_CSLICE_WIDTH ilog2(XEHP_CCS_MODE_CSLICE_MASK + 1)
+#define XEHP_CCS_MODE_CSLICE(cslice, ccs) (ccs << (cslice * XEHP_CCS_MODE_CSLICE_WIDTH))
+
#define CHV_FUSE_GT _MMIO(VLV_GUNIT_BASE + 0x2168)
#define CHV_FGT_DISABLE_SS0 (1 << 10)
#define CHV_FGT_DISABLE_SS1 (1 << 11)
--
2.43.0
