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Disable automatic load CCS load balancing

PATCH In review Andi Shyti 5 participants 17 messages Feb 15, 2024 – Feb 20, 2024

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Andi Shyti

author
#0 lore raw

cover Disable automatic load CCS load balancing

Hi,

this series does basically two things:

1. Disables automatic load balancing as adviced by the hardware workaround.

2. Forces the sharing of the load submitted to CCS among all the CCS available (as of now only DG2 has more than one CCS). This way the user, when sending a query, will see only one CCS available.

Andi

Andi Shyti (2):
drm/i915/gt: Disable HW load balancing for CCS
drm/i915/gt: Set default CCS mode '1'

 drivers/gpu/drm/i915/gt/intel_gt.c          | 11 +++++++++++
 drivers/gpu/drm/i915/gt/intel_gt_regs.h     |  3 +++
 drivers/gpu/drm/i915/gt/intel_workarounds.c |  6 ++++++
 drivers/gpu/drm/i915/i915_drv.h             | 17 +++++++++++++++++
 drivers/gpu/drm/i915/i915_query.c           |  5 +++--
 5 files changed, 40 insertions(+), 2 deletions(-)
Signature · 1 line
2.43.0
author
#1 lore raw

PATCH 1/2 drm/i915/gt: Disable HW load balancing for CCS

The hardware should not dynamically balance the load between CCS engines. Wa_16016805146 recommends disabling it across all platforms.

Fixes d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Cc Chris Wilson <[email protected]>
Cc Joonas Lahtinen <[email protected]>
Cc Matt Roper <[email protected]>
Cc <[email protected]> # v6.2+
---
 drivers/gpu/drm/i915/gt/intel_gt_regs.h     | 1 +
 drivers/gpu/drm/i915/gt/intel_workarounds.c | 6 ++++++
 2 files changed, 7 insertions(+)
drivers/gpu/drm/i915/gt/intel_gt_regs.h +1 -0
index 50962cfd1353..cf709f6c05ae 100644
@@ -1478,6 +1478,7 @@
 
 #define GEN12_RCU_MODE				_MMIO(0x14800)
 #define   GEN12_RCU_MODE_CCS_ENABLE		REG_BIT(0)
+#define   XEHP_RCU_MODE_FIXED_SLICE_CCS_MODE	REG_BIT(1)
 
 #define CHV_FUSE_GT				_MMIO(VLV_GUNIT_BASE + 0x2168)
 #define   CHV_FGT_DISABLE_SS0			(1 << 10)
drivers/gpu/drm/i915/gt/intel_workarounds.c +6 -0
index d67d44611c28..7f42c8015f71 100644
@@ -2988,6 +2988,12 @@ general_render_compute_wa_init(struct intel_engine_cs *engine, struct i915_wa_li
 		wa_mcr_masked_en(wal, GEN8_HALF_SLICE_CHICKEN1,
 				 GEN7_PSD_SINGLE_PORT_DISPATCH_ENABLE);
 	}
+
+	/*
+	 * Wa_16016805146: disable the CCS load balancing
+	 * indiscriminately for all the platforms
+	 */
+	wa_masked_en(wal, GEN12_RCU_MODE, XEHP_RCU_MODE_FIXED_SLICE_CCS_MODE);
 }
 
 static void
Signature · 1 line
2.43.0
#2 lore raw

Re: [PATCH 1/2] drm/i915/gt: Disable HW load balancing for CCS

Quoted 2 lines · Andi Shyti

The hardware should not dynamically balance the load between CCS engines. Wa_16016805146 recommends disabling it across all

Is this the right workaround number? When I check the database, this workaround was rejected on both DG2-G10 and DG2-G11, and doesn't even have an entry for DG2-G12.

There are other workarounds that sound somewhat related to load balancing (e.g., part 3 of Wa_14019159160), but what's asked there is more involved than just setting one register bit and conflicts a bit with the second patch of this series.

Matt

Quoted 45 lines

platforms.

Fixes d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Cc Chris Wilson <[email protected]>
Cc Joonas Lahtinen <[email protected]>
Cc Matt Roper <[email protected]>
Cc <[email protected]> # v6.2+
---
 drivers/gpu/drm/i915/gt/intel_gt_regs.h     | 1 +
 drivers/gpu/drm/i915/gt/intel_workarounds.c | 6 ++++++
 2 files changed, 7 insertions(+)
drivers/gpu/drm/i915/gt/intel_gt_regs.h +1 -0
index 50962cfd1353..cf709f6c05ae 100644
@@ -1478,6 +1478,7 @@
 
 #define GEN12_RCU_MODE				_MMIO(0x14800)
 #define   GEN12_RCU_MODE_CCS_ENABLE		REG_BIT(0)
+#define   XEHP_RCU_MODE_FIXED_SLICE_CCS_MODE	REG_BIT(1)
 
 #define CHV_FUSE_GT				_MMIO(VLV_GUNIT_BASE + 0x2168)
 #define   CHV_FGT_DISABLE_SS0			(1 << 10)
drivers/gpu/drm/i915/gt/intel_workarounds.c +6 -0
index d67d44611c28..7f42c8015f71 100644
@@ -2988,6 +2988,12 @@ general_render_compute_wa_init(struct intel_engine_cs *engine, struct i915_wa_li
 		wa_mcr_masked_en(wal, GEN8_HALF_SLICE_CHICKEN1,
 				 GEN7_PSD_SINGLE_PORT_DISPATCH_ENABLE);
 	}
+
+	/*
+	 * Wa_16016805146: disable the CCS load balancing
+	 * indiscriminately for all the platforms
+	 */
+	wa_masked_en(wal, GEN12_RCU_MODE, XEHP_RCU_MODE_FIXED_SLICE_CCS_MODE);
 }
 
 static void
Signature · 1 line
2.43.0
Signature · 4 lines
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation
author
#3 lore raw

Re: [PATCH 1/2] drm/i915/gt: Disable HW load balancing for CCS

Hi Matt,

Quoted 4 lines · Matt Roper
Quoted 2 lines · Andi Shyti

The hardware should not dynamically balance the load between CCS engines. Wa_16016805146 recommends disabling it across all

Quoted 8 lines

Is this the right workaround number? When I check the database, this workaround was rejected on both DG2-G10 and DG2-G11, and doesn't even have an entry for DG2-G12.

There are other workarounds that sound somewhat related to load balancing (e.g., part 3 of Wa_14019159160), but what's asked there is more involved than just setting one register bit and conflicts a bit with the second patch of this series.

thanks for checking it. Indeed the WA I mentioned is limited to a specific platform. This recommendation comes in different WA, e.g. this one: Wa_14019186972 (3rd point). Will start using that as a reference.

Thank you.
Andi

Quoted 55 lines

Matt

Quoted 45 lines

platforms.

Fixes d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Cc Chris Wilson <[email protected]>
Cc Joonas Lahtinen <[email protected]>
Cc Matt Roper <[email protected]>
Cc <[email protected]> # v6.2+
---
 drivers/gpu/drm/i915/gt/intel_gt_regs.h     | 1 +
 drivers/gpu/drm/i915/gt/intel_workarounds.c | 6 ++++++
 2 files changed, 7 insertions(+)
drivers/gpu/drm/i915/gt/intel_gt_regs.h +1 -0
index 50962cfd1353..cf709f6c05ae 100644
@@ -1478,6 +1478,7 @@
 
 #define GEN12_RCU_MODE				_MMIO(0x14800)
 #define   GEN12_RCU_MODE_CCS_ENABLE		REG_BIT(0)
+#define   XEHP_RCU_MODE_FIXED_SLICE_CCS_MODE	REG_BIT(1)
 
 #define CHV_FUSE_GT				_MMIO(VLV_GUNIT_BASE + 0x2168)
 #define   CHV_FGT_DISABLE_SS0			(1 << 10)
drivers/gpu/drm/i915/gt/intel_workarounds.c +6 -0
index d67d44611c28..7f42c8015f71 100644
@@ -2988,6 +2988,12 @@ general_render_compute_wa_init(struct intel_engine_cs *engine, struct i915_wa_li
 		wa_mcr_masked_en(wal, GEN8_HALF_SLICE_CHICKEN1,
 				 GEN7_PSD_SINGLE_PORT_DISPATCH_ENABLE);
 	}
+
+	/*
+	 * Wa_16016805146: disable the CCS load balancing
+	 * indiscriminately for all the platforms
+	 */
+	wa_masked_en(wal, GEN12_RCU_MODE, XEHP_RCU_MODE_FIXED_SLICE_CCS_MODE);
 }
 
 static void
Signature · 1 line
2.43.0
Signature · 4 lines
Matt Roper
Graphics Software Engineer
Linux GPU Platform Enablement
Intel Corporation
author
#4 lore raw

Re: [PATCH 1/2] drm/i915/gt: Disable HW load balancing for CCS

Quoted 14 lines · Andi Shyti
Quoted 4 lines · Matt Roper
Quoted 2 lines · Andi Shyti

The hardware should not dynamically balance the load between CCS engines. Wa_16016805146 recommends disabling it across all

Quoted 8 lines

Is this the right workaround number? When I check the database, this workaround was rejected on both DG2-G10 and DG2-G11, and doesn't even have an entry for DG2-G12.

There are other workarounds that sound somewhat related to load balancing (e.g., part 3 of Wa_14019159160), but what's asked there is more involved than just setting one register bit and conflicts a bit with the second patch of this series.

Quoted 4 lines

thanks for checking it. Indeed the WA I mentioned is limited to a specific platform. This recommendation comes in different WA, e.g. this one: Wa_14019186972 (3rd point). Will start using that as a reference.

actually you are right, I checked with Joonas and I will use Wa_14019159160.

Thanks,
Andi

author
#5 lore raw

PATCH 2/2 drm/i915/gt: Set default CCS mode '1'

In reply to Andi Shyti

Since CCS automatic load balancing is disabled, we will impose a fixed balancing policy that involves setting all the CCS engines to work together on the same load.

Simultaneously, the user will see only 1 CCS rather than the actual number. As of now, this change affects only DG2.

Fixes d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Cc Chris Wilson <[email protected]>
Cc Joonas Lahtinen <[email protected]>
Cc Matt Roper <[email protected]>
Cc <[email protected]> # v6.2+
---
 drivers/gpu/drm/i915/gt/intel_gt.c      | 11 +++++++++++
 drivers/gpu/drm/i915/gt/intel_gt_regs.h |  2 ++
 drivers/gpu/drm/i915/i915_drv.h         | 17 +++++++++++++++++
 drivers/gpu/drm/i915/i915_query.c       |  5 +++--
 4 files changed, 33 insertions(+), 2 deletions(-)
drivers/gpu/drm/i915/gt/intel_gt.c +11 -0
index a425db5ed3a2..e19df4ef47f6 100644
@@ -168,6 +168,14 @@ static void init_unused_rings(struct intel_gt *gt)
 	}
 }
 
+static void intel_gt_apply_ccs_mode(struct intel_gt *gt)
+{
+	if (!IS_DG2(gt->i915))
+		return;
+
+	intel_uncore_write(gt->uncore, XEHP_CCS_MODE, 0);
+}
+
 int intel_gt_init_hw(struct intel_gt *gt)
 {
 	struct drm_i915_private *i915 = gt->i915;
@@ -195,6 +203,9 @@ 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
drivers/gpu/drm/i915/gt/intel_gt_regs.h +2 -0
index cf709f6c05ae..c148113770ea 100644
@@ -1605,6 +1605,8 @@
 #define   GEN12_VOLTAGE_MASK			REG_GENMASK(10, 0)
 #define   GEN12_CAGF_MASK			REG_GENMASK(19, 11)
 
+#define XEHP_CCS_MODE                          _MMIO(0x14804)
+
 #define GEN11_GT_INTR_DW(x)			_MMIO(0x190018 + ((x) * 4))
 #define   GEN11_CSME				(31)
 #define   GEN12_HECI_2				(30)
drivers/gpu/drm/i915/i915_drv.h +17 -0
index e81b3b2858ac..0853ffd3cb8d 100644
@@ -396,6 +396,23 @@ static inline struct intel_gt *to_gt(const struct drm_i915_private *i915)
 	     (engine__); \
 	     (engine__) = rb_to_uabi_engine(rb_next(&(engine__)->uabi_node)))
 
+/*
+ * Exclude unavailable engines.
+ *
+ * Only the first CCS engine is utilized due to the disabling of CCS auto load
+ * balancing. As a result, all CCS engines operate collectively, functioning
+ * essentially as a single CCS engine, hence the count of active CCS engines is
+ * considered '1'.
+ * Currently, this applies to platforms with more than one CCS engine,
+ * specifically DG2.
+ */
+#define for_each_available_uabi_engine(engine__, i915__) \
+	for_each_uabi_engine(engine__, i915__) \
+		if ((IS_DG2(i915__)) && \
+		    ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+		    ((engine__)->uabi_instance)) { } \
+		else
+
 #define INTEL_INFO(i915)	((i915)->__info)
 #define RUNTIME_INFO(i915)	(&(i915)->__runtime)
 #define DRIVER_CAPS(i915)	(&(i915)->caps)
drivers/gpu/drm/i915/i915_query.c +3 -2
index fa3e937ed3f5..2d41bda626a6 100644
@@ -124,6 +124,7 @@ static int query_geometry_subslices(struct drm_i915_private *i915,
 	return fill_topology_info(sseu, query_item, sseu->geometry_subslice_mask);
 }
 
+
 static int
 query_engine_info(struct drm_i915_private *i915,
 		  struct drm_i915_query_item *query_item)
@@ -140,7 +141,7 @@ query_engine_info(struct drm_i915_private *i915,
 	if (query_item->flags)
 		return -EINVAL;
 
-	for_each_uabi_engine(engine, i915)
+	for_each_available_uabi_engine(engine, i915)
 		num_uabi_engines++;
 
 	len = struct_size(query_ptr, engines, num_uabi_engines);
@@ -155,7 +156,7 @@ query_engine_info(struct drm_i915_private *i915,
 
 	info_ptr = &query_ptr->engines[0];
 
-	for_each_uabi_engine(engine, i915) {
+	for_each_available_uabi_engine(engine, i915) {
 		info.engine.engine_class = engine->uabi_class;
 		info.engine.engine_instance = engine->uabi_instance;
 		info.flags = I915_ENGINE_INFO_HAS_LOGICAL_INSTANCE;
Signature · 1 line
2.43.0
#6 lore raw

Re: [PATCH 2/2] drm/i915/gt: Set default CCS mode '1'

Quoted 6 lines · Andi Shyti

Since CCS automatic load balancing is disabled, we will impose a fixed balancing policy that involves setting all the CCS engines to work together on the same load.

Simultaneously, the user will see only 1 CCS rather than the actual number. As of now, this change affects only DG2.

These two paragraphs are mutually exclusive. You can't have four CCS engines 'working together' if only one engine exists. I think you are meaning that we only export 1 CCS engine and that single engine is configured to control all the EUs. As opposed to running in 4 CCS engine mode where the EUs are (dynamically or statically) divided amongst those four engines.

John.

Quoted 114 lines
Fixes d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Cc Chris Wilson <[email protected]>
Cc Joonas Lahtinen <[email protected]>
Cc Matt Roper <[email protected]>
Cc <[email protected]> # v6.2+
---
  drivers/gpu/drm/i915/gt/intel_gt.c      | 11 +++++++++++
  drivers/gpu/drm/i915/gt/intel_gt_regs.h |  2 ++
  drivers/gpu/drm/i915/i915_drv.h         | 17 +++++++++++++++++
  drivers/gpu/drm/i915/i915_query.c       |  5 +++--
  4 files changed, 33 insertions(+), 2 deletions(-)
drivers/gpu/drm/i915/gt/intel_gt.c +11 -0
index a425db5ed3a2..e19df4ef47f6 100644
@@ -168,6 +168,14 @@ static void init_unused_rings(struct intel_gt *gt)
  	}
  }
 
+static void intel_gt_apply_ccs_mode(struct intel_gt *gt)
+{
+	if (!IS_DG2(gt->i915))
+		return;
+
+	intel_uncore_write(gt->uncore, XEHP_CCS_MODE, 0);
+}
+
  int intel_gt_init_hw(struct intel_gt *gt)
  {
  	struct drm_i915_private *i915 = gt->i915;
@@ -195,6 +203,9 @@ 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
drivers/gpu/drm/i915/gt/intel_gt_regs.h +2 -0
index cf709f6c05ae..c148113770ea 100644
@@ -1605,6 +1605,8 @@
  #define   GEN12_VOLTAGE_MASK			REG_GENMASK(10, 0)
  #define   GEN12_CAGF_MASK			REG_GENMASK(19, 11)
 
+#define XEHP_CCS_MODE                          _MMIO(0x14804)
+
  #define GEN11_GT_INTR_DW(x)			_MMIO(0x190018 + ((x) * 4))
  #define   GEN11_CSME				(31)
  #define   GEN12_HECI_2				(30)
drivers/gpu/drm/i915/i915_drv.h +17 -0
index e81b3b2858ac..0853ffd3cb8d 100644
@@ -396,6 +396,23 @@ static inline struct intel_gt *to_gt(const struct drm_i915_private *i915)
  	     (engine__); \
  	     (engine__) = rb_to_uabi_engine(rb_next(&(engine__)->uabi_node)))
 
+/*
+ * Exclude unavailable engines.
+ *
+ * Only the first CCS engine is utilized due to the disabling of CCS auto load
+ * balancing. As a result, all CCS engines operate collectively, functioning
+ * essentially as a single CCS engine, hence the count of active CCS engines is
+ * considered '1'.
+ * Currently, this applies to platforms with more than one CCS engine,
+ * specifically DG2.
+ */
+#define for_each_available_uabi_engine(engine__, i915__) \
+	for_each_uabi_engine(engine__, i915__) \
+		if ((IS_DG2(i915__)) && \
+		    ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+		    ((engine__)->uabi_instance)) { } \
+		else
+
  #define INTEL_INFO(i915)	((i915)->__info)
  #define RUNTIME_INFO(i915)	(&(i915)->__runtime)
  #define DRIVER_CAPS(i915)	(&(i915)->caps)
drivers/gpu/drm/i915/i915_query.c +3 -2
index fa3e937ed3f5..2d41bda626a6 100644
@@ -124,6 +124,7 @@ static int query_geometry_subslices(struct drm_i915_private *i915,
  	return fill_topology_info(sseu, query_item, sseu->geometry_subslice_mask);
  }
 
+
  static int
  query_engine_info(struct drm_i915_private *i915,
  		  struct drm_i915_query_item *query_item)
@@ -140,7 +141,7 @@ query_engine_info(struct drm_i915_private *i915,
  	if (query_item->flags)
  		return -EINVAL;
 
-	for_each_uabi_engine(engine, i915)
+	for_each_available_uabi_engine(engine, i915)
  		num_uabi_engines++;
 
  	len = struct_size(query_ptr, engines, num_uabi_engines);
@@ -155,7 +156,7 @@ query_engine_info(struct drm_i915_private *i915,
 
  	info_ptr = &query_ptr->engines[0];
 
-	for_each_uabi_engine(engine, i915) {
+	for_each_available_uabi_engine(engine, i915) {
  		info.engine.engine_class = engine->uabi_class;
  		info.engine.engine_instance = engine->uabi_instance;
  		info.flags = I915_ENGINE_INFO_HAS_LOGICAL_INSTANCE;
author
#7 lore raw

Re: [PATCH 2/2] drm/i915/gt: Set default CCS mode '1'

Hi John,

Quoted 5 lines · John Harrison
Quoted 4 lines · Andi Shyti

Since CCS automatic load balancing is disabled, we will impose a fixed balancing policy that involves setting all the CCS engines to work together on the same load.

Quoted 7 lines
Quoted 2 lines

Simultaneously, the user will see only 1 CCS rather than the actual number. As of now, this change affects only DG2.

These two paragraphs are mutually exclusive. You can't have four CCS engines 'working together' if only one engine exists. I think you are meaning that we only export 1 CCS engine and that single engine is configured to control all the EUs. As opposed to running in 4 CCS engine mode where the EUs are (dynamically or statically) divided amongst those four engines.

The balancing is done statically. The dynamic balancing is disabled in patch 1.

The 2 or 4 CCS engines will share the same workload.

Because the user won't be able anymore to select the CCS engine he wants to use, he will see only one CCS.

I think we are saying the same thing using different words :) I can try in v2 to reword the commit better.

Thanks for looking into this.
Andi

Quoted 106 lines

John.

Quoted 104 lines
Fixes d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Cc Chris Wilson <[email protected]>
Cc Joonas Lahtinen <[email protected]>
Cc Matt Roper <[email protected]>
Cc <[email protected]> # v6.2+
---
  drivers/gpu/drm/i915/gt/intel_gt.c      | 11 +++++++++++
  drivers/gpu/drm/i915/gt/intel_gt_regs.h |  2 ++
  drivers/gpu/drm/i915/i915_drv.h         | 17 +++++++++++++++++
  drivers/gpu/drm/i915/i915_query.c       |  5 +++--
  4 files changed, 33 insertions(+), 2 deletions(-)
drivers/gpu/drm/i915/gt/intel_gt.c +11 -0
index a425db5ed3a2..e19df4ef47f6 100644
@@ -168,6 +168,14 @@ static void init_unused_rings(struct intel_gt *gt)
  	}
  }
+static void intel_gt_apply_ccs_mode(struct intel_gt *gt)
+{
+	if (!IS_DG2(gt->i915))
+		return;
+
+	intel_uncore_write(gt->uncore, XEHP_CCS_MODE, 0);
+}
+
  int intel_gt_init_hw(struct intel_gt *gt)
  {
  	struct drm_i915_private *i915 = gt->i915;
@@ -195,6 +203,9 @@ 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
drivers/gpu/drm/i915/gt/intel_gt_regs.h +2 -0
index cf709f6c05ae..c148113770ea 100644
@@ -1605,6 +1605,8 @@
  #define   GEN12_VOLTAGE_MASK			REG_GENMASK(10, 0)
  #define   GEN12_CAGF_MASK			REG_GENMASK(19, 11)
+#define XEHP_CCS_MODE                          _MMIO(0x14804)
+
  #define GEN11_GT_INTR_DW(x)			_MMIO(0x190018 + ((x) * 4))
  #define   GEN11_CSME				(31)
  #define   GEN12_HECI_2				(30)
drivers/gpu/drm/i915/i915_drv.h +17 -0
index e81b3b2858ac..0853ffd3cb8d 100644
@@ -396,6 +396,23 @@ static inline struct intel_gt *to_gt(const struct drm_i915_private *i915)
  	     (engine__); \
  	     (engine__) = rb_to_uabi_engine(rb_next(&(engine__)->uabi_node)))
+/*
+ * Exclude unavailable engines.
+ *
+ * Only the first CCS engine is utilized due to the disabling of CCS auto load
+ * balancing. As a result, all CCS engines operate collectively, functioning
+ * essentially as a single CCS engine, hence the count of active CCS engines is
+ * considered '1'.
+ * Currently, this applies to platforms with more than one CCS engine,
+ * specifically DG2.
+ */
+#define for_each_available_uabi_engine(engine__, i915__) \
+	for_each_uabi_engine(engine__, i915__) \
+		if ((IS_DG2(i915__)) && \
+		    ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+		    ((engine__)->uabi_instance)) { } \
+		else
+
  #define INTEL_INFO(i915)	((i915)->__info)
  #define RUNTIME_INFO(i915)	(&(i915)->__runtime)
  #define DRIVER_CAPS(i915)	(&(i915)->caps)
drivers/gpu/drm/i915/i915_query.c +3 -2
index fa3e937ed3f5..2d41bda626a6 100644
@@ -124,6 +124,7 @@ static int query_geometry_subslices(struct drm_i915_private *i915,
  	return fill_topology_info(sseu, query_item, sseu->geometry_subslice_mask);
  }
+
  static int
  query_engine_info(struct drm_i915_private *i915,
  		  struct drm_i915_query_item *query_item)
@@ -140,7 +141,7 @@ query_engine_info(struct drm_i915_private *i915,
  	if (query_item->flags)
  		return -EINVAL;
-	for_each_uabi_engine(engine, i915)
+	for_each_available_uabi_engine(engine, i915)
  		num_uabi_engines++;
  	len = struct_size(query_ptr, engines, num_uabi_engines);
@@ -155,7 +156,7 @@ query_engine_info(struct drm_i915_private *i915,
  	info_ptr = &query_ptr->engines[0];
-	for_each_uabi_engine(engine, i915) {
+	for_each_available_uabi_engine(engine, i915) {
  		info.engine.engine_class = engine->uabi_class;
  		info.engine.engine_instance = engine->uabi_instance;
  		info.flags = I915_ENGINE_INFO_HAS_LOGICAL_INSTANCE;
#8 lore raw

Re: [PATCH 2/2] drm/i915/gt: Set default CCS mode '1'

Quoted 15 lines · Andi Shyti

Hi John,

Quoted 5 lines · John Harrison
Quoted 4 lines · Andi Shyti

Since CCS automatic load balancing is disabled, we will impose a fixed balancing policy that involves setting all the CCS engines to work together on the same load.

Quoted 7 lines
Quoted 2 lines

Simultaneously, the user will see only 1 CCS rather than the actual number. As of now, this change affects only DG2.

These two paragraphs are mutually exclusive. You can't have four CCS engines 'working together' if only one engine exists. I think you are meaning that we only export 1 CCS engine and that single engine is configured to control all the EUs. As opposed to running in 4 CCS engine mode where the EUs are (dynamically or statically) divided amongst those four engines.

Quoted 4 lines

The balancing is done statically. The dynamic balancing is disabled in patch 1.

The 2 or 4 CCS engines will share the same workload.

But they don't.

In i915, we use 'engine' to refer to a command streamer and all the associated hardware. This is distinct from the EUs which sit behind and can be driven by one or more command streamers. Saying that multiple engines are sharing a workload implies that you are submitting the context to multiple command streamers in parallel. I.e. a similar process to media frame split where they have a set of LRCA contexts bound together which are submitted in parallel to two or more video decode engines (VCS0, VCS1, etc.). That is not what is happening here.

Here, you are submitting a single context with a singe ring buffer to a single engine - CCS0. That engine is configured to own all EUs. Which actually means that submitting a compute task to another CCS engine will achieve nothing because there are no EUs available to those other engines. They will simply hang when waiting for the walker instruction to complete.

Quoted 5 lines

Because the user won't be able anymore to select the CCS engine he wants to use, he will see only one CCS.

I think we are saying the same thing using different words :)

But words are important.

John.

Quoted 110 lines

I can try in v2 to reword the commit better.

Thanks for looking into this.
Andi

Quoted 105 lines

John.

Quoted 103 lines
Fixes d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Cc Chris Wilson <[email protected]>
Cc Joonas Lahtinen <[email protected]>
Cc Matt Roper <[email protected]>
Cc <[email protected]> # v6.2+
---
   drivers/gpu/drm/i915/gt/intel_gt.c      | 11 +++++++++++
   drivers/gpu/drm/i915/gt/intel_gt_regs.h |  2 ++
   drivers/gpu/drm/i915/i915_drv.h         | 17 +++++++++++++++++
   drivers/gpu/drm/i915/i915_query.c       |  5 +++--
   4 files changed, 33 insertions(+), 2 deletions(-)
drivers/gpu/drm/i915/gt/intel_gt.c +11 -0
index a425db5ed3a2..e19df4ef47f6 100644
@@ -168,6 +168,14 @@ static void init_unused_rings(struct intel_gt *gt)
   	}
   }
+static void intel_gt_apply_ccs_mode(struct intel_gt *gt)
+{
+	if (!IS_DG2(gt->i915))
+		return;
+
+	intel_uncore_write(gt->uncore, XEHP_CCS_MODE, 0);
+}
+
   int intel_gt_init_hw(struct intel_gt *gt)
   {
   	struct drm_i915_private *i915 = gt->i915;
@@ -195,6 +203,9 @@ 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
drivers/gpu/drm/i915/gt/intel_gt_regs.h +2 -0
index cf709f6c05ae..c148113770ea 100644
@@ -1605,6 +1605,8 @@
   #define   GEN12_VOLTAGE_MASK			REG_GENMASK(10, 0)
   #define   GEN12_CAGF_MASK			REG_GENMASK(19, 11)
+#define XEHP_CCS_MODE                          _MMIO(0x14804)
+
   #define GEN11_GT_INTR_DW(x)			_MMIO(0x190018 + ((x) * 4))
   #define   GEN11_CSME				(31)
   #define   GEN12_HECI_2				(30)
drivers/gpu/drm/i915/i915_drv.h +17 -0
index e81b3b2858ac..0853ffd3cb8d 100644
@@ -396,6 +396,23 @@ static inline struct intel_gt *to_gt(const struct drm_i915_private *i915)
   	     (engine__); \
   	     (engine__) = rb_to_uabi_engine(rb_next(&(engine__)->uabi_node)))
+/*
+ * Exclude unavailable engines.
+ *
+ * Only the first CCS engine is utilized due to the disabling of CCS auto load
+ * balancing. As a result, all CCS engines operate collectively, functioning
+ * essentially as a single CCS engine, hence the count of active CCS engines is
+ * considered '1'.
+ * Currently, this applies to platforms with more than one CCS engine,
+ * specifically DG2.
+ */
+#define for_each_available_uabi_engine(engine__, i915__) \
+	for_each_uabi_engine(engine__, i915__) \
+		if ((IS_DG2(i915__)) && \
+		    ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+		    ((engine__)->uabi_instance)) { } \
+		else
+
   #define INTEL_INFO(i915)	((i915)->__info)
   #define RUNTIME_INFO(i915)	(&(i915)->__runtime)
   #define DRIVER_CAPS(i915)	(&(i915)->caps)
drivers/gpu/drm/i915/i915_query.c +3 -2
index fa3e937ed3f5..2d41bda626a6 100644
@@ -124,6 +124,7 @@ static int query_geometry_subslices(struct drm_i915_private *i915,
   	return fill_topology_info(sseu, query_item, sseu->geometry_subslice_mask);
   }
+
   static int
   query_engine_info(struct drm_i915_private *i915,
   		  struct drm_i915_query_item *query_item)
@@ -140,7 +141,7 @@ query_engine_info(struct drm_i915_private *i915,
   	if (query_item->flags)
   		return -EINVAL;
-	for_each_uabi_engine(engine, i915)
+	for_each_available_uabi_engine(engine, i915)
   		num_uabi_engines++;
   	len = struct_size(query_ptr, engines, num_uabi_engines);
@@ -155,7 +156,7 @@ query_engine_info(struct drm_i915_private *i915,
   	info_ptr = &query_ptr->engines[0];
-	for_each_uabi_engine(engine, i915) {
+	for_each_available_uabi_engine(engine, i915) {
   		info.engine.engine_class = engine->uabi_class;
   		info.engine.engine_instance = engine->uabi_instance;
   		info.flags = I915_ENGINE_INFO_HAS_LOGICAL_INSTANCE;
#9 lore raw

Re: [PATCH 2/2] drm/i915/gt: Set default CCS mode '1'

In reply to Andi Shyti
Quoted 77 lines · Andi Shyti

Since CCS automatic load balancing is disabled, we will impose a fixed balancing policy that involves setting all the CCS engines to work together on the same load.

Simultaneously, the user will see only 1 CCS rather than the actual number. As of now, this change affects only DG2.

Fixes d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Cc Chris Wilson <[email protected]>
Cc Joonas Lahtinen <[email protected]>
Cc Matt Roper <[email protected]>
Cc <[email protected]> # v6.2+
---
  drivers/gpu/drm/i915/gt/intel_gt.c      | 11 +++++++++++
  drivers/gpu/drm/i915/gt/intel_gt_regs.h |  2 ++
  drivers/gpu/drm/i915/i915_drv.h         | 17 +++++++++++++++++
  drivers/gpu/drm/i915/i915_query.c       |  5 +++--
  4 files changed, 33 insertions(+), 2 deletions(-)
drivers/gpu/drm/i915/gt/intel_gt.c +11 -0
index a425db5ed3a2..e19df4ef47f6 100644
@@ -168,6 +168,14 @@ static void init_unused_rings(struct intel_gt *gt)
  	}
  }
 
+static void intel_gt_apply_ccs_mode(struct intel_gt *gt)
+{
+	if (!IS_DG2(gt->i915))
+		return;
+
+	intel_uncore_write(gt->uncore, XEHP_CCS_MODE, 0);
+}
+
  int intel_gt_init_hw(struct intel_gt *gt)
  {
  	struct drm_i915_private *i915 = gt->i915;
@@ -195,6 +203,9 @@ 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
drivers/gpu/drm/i915/gt/intel_gt_regs.h +2 -0
index cf709f6c05ae..c148113770ea 100644
@@ -1605,6 +1605,8 @@
  #define   GEN12_VOLTAGE_MASK			REG_GENMASK(10, 0)
  #define   GEN12_CAGF_MASK			REG_GENMASK(19, 11)
 
+#define XEHP_CCS_MODE                          _MMIO(0x14804)
+
  #define GEN11_GT_INTR_DW(x)			_MMIO(0x190018 + ((x) * 4))
  #define   GEN11_CSME				(31)
  #define   GEN12_HECI_2				(30)
drivers/gpu/drm/i915/i915_drv.h +7 -0
index e81b3b2858ac..0853ffd3cb8d 100644
@@ -396,6 +396,23 @@ static inline struct intel_gt *to_gt(const struct drm_i915_private *i915)
  	     (engine__); \
  	     (engine__) = rb_to_uabi_engine(rb_next(&(engine__)->uabi_node)))
 
+/*
+ * Exclude unavailable engines.
+ *
+ * Only the first CCS engine is utilized due to the disabling of CCS auto load
+ * balancing. As a result, all CCS engines operate collectively, functioning
+ * essentially as a single CCS engine, hence the count of active CCS engines is
+ * considered '1'.

drivers/gpu/drm/i915/i915_drv.h static inline struct intel_gt *to_gt(const struct drm_i915_private *i915) · line 415

Quoted 10 lines
drivers/gpu/drm/i915/i915_drv.h +10 -0
+ * Currently, this applies to platforms with more than one CCS engine,
+ * specifically DG2.
+ */
+#define for_each_available_uabi_engine(engine__, i915__) \
+	for_each_uabi_engine(engine__, i915__) \
+		if ((IS_DG2(i915__)) && \
+		    ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+		    ((engine__)->uabi_instance)) { } \
+		else
+

If you don't want userspace to see some engines, just don't add them to the uabi list in intel_engines_driver_register or thereabouts?

Similar as we do for gsc which uses I915_NO_UABI_CLASS, although for ccs you can choose a different approach, whatever is more elegant.

That is also needed for i915->engine_uabi_class_count to be right, so userspace stats which rely on it are correct.

Regards,

Tvrtko

Quoted 33 lines
drivers/gpu/drm/i915/i915_drv.h +0 -0
  #define INTEL_INFO(i915)	((i915)->__info)
  #define RUNTIME_INFO(i915)	(&(i915)->__runtime)
  #define DRIVER_CAPS(i915)	(&(i915)->caps)
drivers/gpu/drm/i915/i915_query.c +3 -2
index fa3e937ed3f5..2d41bda626a6 100644
@@ -124,6 +124,7 @@ static int query_geometry_subslices(struct drm_i915_private *i915,
  	return fill_topology_info(sseu, query_item, sseu->geometry_subslice_mask);
  }
 
+
  static int
  query_engine_info(struct drm_i915_private *i915,
  		  struct drm_i915_query_item *query_item)
@@ -140,7 +141,7 @@ query_engine_info(struct drm_i915_private *i915,
  	if (query_item->flags)
  		return -EINVAL;
 
-	for_each_uabi_engine(engine, i915)
+	for_each_available_uabi_engine(engine, i915)
  		num_uabi_engines++;
 
  	len = struct_size(query_ptr, engines, num_uabi_engines);
@@ -155,7 +156,7 @@ query_engine_info(struct drm_i915_private *i915,
 
  	info_ptr = &query_ptr->engines[0];
 
-	for_each_uabi_engine(engine, i915) {
+	for_each_available_uabi_engine(engine, i915) {
  		info.engine.engine_class = engine->uabi_class;
  		info.engine.engine_instance = engine->uabi_instance;
  		info.flags = I915_ENGINE_INFO_HAS_LOGICAL_INSTANCE;
#10 lore raw

Re: [PATCH 2/2] drm/i915/gt: Set default CCS mode '1'

Quoted 91 lines · Tvrtko Ursulin
Quoted 79 lines · Andi Shyti

Since CCS automatic load balancing is disabled, we will impose a fixed balancing policy that involves setting all the CCS engines to work together on the same load.

Simultaneously, the user will see only 1 CCS rather than the actual number. As of now, this change affects only DG2.

Fixes d2eae8e98d59 ("drm/i915/dg2: Drop force_probe requirement")
Cc Chris Wilson <[email protected]>
Cc Joonas Lahtinen <[email protected]>
Cc Matt Roper <[email protected]>
Cc <[email protected]> # v6.2+

---
  drivers/gpu/drm/i915/gt/intel_gt.c      | 11 +++++++++++ drivers/gpu/drm/i915/gt/intel_gt_regs.h |  2 ++ drivers/gpu/drm/i915/i915_drv.h         | 17 +++++++++++++++++ drivers/gpu/drm/i915/i915_query.c       |  5 +++--

  4 files changed, 33 insertions(+), 2 deletions(-)
drivers/gpu/drm/i915/gt/intel_gt.c +11 -0
index a425db5ed3a2..e19df4ef47f6 100644
@@ -168,6 +168,14 @@ static void init_unused_rings(struct intel_gt *gt)
       }
   }
+static void intel_gt_apply_ccs_mode(struct intel_gt *gt)
+{
+    if (!IS_DG2(gt->i915))
+        return;
+
+    intel_uncore_write(gt->uncore, XEHP_CCS_MODE, 0);
+}
+
   int intel_gt_init_hw(struct intel_gt *gt)
   {
       struct drm_i915_private *i915 = gt->i915;
@@ -195,6 +203,9 @@ 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
drivers/gpu/drm/i915/gt/intel_gt_regs.h +2 -0
index cf709f6c05ae..c148113770ea 100644
@@ -1605,6 +1605,8 @@
   #define   GEN12_VOLTAGE_MASK            REG_GENMASK(10, 0)
   #define   GEN12_CAGF_MASK            REG_GENMASK(19, 11)
+#define XEHP_CCS_MODE                          _MMIO(0x14804)
+
   #define GEN11_GT_INTR_DW(x)            _MMIO(0x190018 + ((x) * 4))
   #define   GEN11_CSME                (31)
   #define   GEN12_HECI_2                (30)
drivers/gpu/drm/i915/i915_drv.h +4 -0
index e81b3b2858ac..0853ffd3cb8d 100644
@@ -396,6 +396,23 @@ static inline struct intel_gt *to_gt(const struct 
 drm_i915_private *i915)
            (engine__); \
            (engine__) = rb_to_uabi_engine(rb_next(&(engine__)->uabi_node)))
+/*
+ * Exclude unavailable engines.
+ *
+ * Only the first CCS engine is utilized due to the disabling of CCS 

auto load
+ * balancing. As a result, all CCS engines operate collectively, functioning
+ * essentially as a single CCS engine, hence the count of active CCS engines is
+ * considered '1'.
+ * Currently, this applies to platforms with more than one CCS engine,
+ * specifically DG2.
+ */

drivers/gpu/drm/i915/i915_drv.h static inline struct intel_gt *to_gt(const struct drm_i915_private *i915) · line 415

Quoted 7 lines
drivers/gpu/drm/i915/i915_drv.h +7 -0
+#define for_each_available_uabi_engine(engine__, i915__) \
+    for_each_uabi_engine(engine__, i915__) \
+        if ((IS_DG2(i915__)) && \
+            ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+            ((engine__)->uabi_instance)) { } \
+        else
+

If you don't want userspace to see some engines, just don't add them to the uabi list in intel_engines_driver_register or thereabouts?

Quoted 3 lines

Similar as we do for gsc which uses I915_NO_UABI_CLASS, although for ccs you can choose a different approach, whatever is more elegant.

That is also needed for i915->engine_uabi_class_count to be right, so userspace stats which rely on it are correct.

I later realized it is more than that - everything that uses intel_engine_lookup_user to look up class instance passed in from userspace relies on the engine not being on the user list otherwise userspace could bypass the fact engine query does not list it. Like PMU, Perf/POA, context engine map and SSEU context query.

Regards,

Tvrtko

Quoted 34 lines

Regards,

Tvrtko

Quoted 29 lines

  #define INTEL_INFO(i915)    ((i915)->__info) #define RUNTIME_INFO(i915)    (&(i915)->__runtime) #define DRIVER_CAPS(i915)    (&(i915)->caps)

drivers/gpu/drm/i915/i915_query.c +1 -0
index fa3e937ed3f5..2d41bda626a6 100644
@@ -124,6 +124,7 @@ static int query_geometry_subslices(struct 
 drm_i915_private *i915,
       return fill_topology_info(sseu, query_item, sseu->geometry_subslice_mask);
   }
+

  static int
  query_engine_info(struct drm_i915_private *i915, struct drm_i915_query_item *query_item)

drivers/gpu/drm/i915/i915_query.c +2 -2
@@ -140,7 +141,7 @@ query_engine_info(struct drm_i915_private *i915,
       if (query_item->flags)
           return -EINVAL;
-    for_each_uabi_engine(engine, i915)
+    for_each_available_uabi_engine(engine, i915)
           num_uabi_engines++;
       len = struct_size(query_ptr, engines, num_uabi_engines);
@@ -155,7 +156,7 @@ query_engine_info(struct drm_i915_private *i915,
       info_ptr = &query_ptr->engines[0];
-    for_each_uabi_engine(engine, i915) {
+    for_each_available_uabi_engine(engine, i915) {
           info.engine.engine_class = engine->uabi_class;
           info.engine.engine_instance = engine->uabi_instance;
           info.flags = I915_ENGINE_INFO_HAS_LOGICAL_INSTANCE;
author
#11 lore raw

Re: [PATCH 2/2] drm/i915/gt: Set default CCS mode '1'

Hi Tvrtko,

Quoted 2 lines · Tvrtko Ursulin
Quoted 1 line · Tvrtko Ursulin

On 15/02/2024 13:59, Andi Shyti wrote:

...

Quoted 15 lines
Quoted 15 lines
Quoted 15 lines

+/*
+ * Exclude unavailable engines.
+ *
+ * Only the first CCS engine is utilized due to the disabling of CCS auto load
+ * balancing. As a result, all CCS engines operate collectively, functioning
+ * essentially as a single CCS engine, hence the count of active CCS engines is
+ * considered '1'.
+ * Currently, this applies to platforms with more than one CCS engine,
+ * specifically DG2.
+ */
+#define for_each_available_uabi_engine(engine__, i915__) \
+    for_each_uabi_engine(engine__, i915__) \

Quoted 8 lines
Quoted 8 lines
Quoted 5 lines

+        if ((IS_DG2(i915__)) && \
+            ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+            ((engine__)->uabi_instance)) { } \
+        else
+

If you don't want userspace to see some engines, just don't add them to the uabi list in intel_engines_driver_register or thereabouts?

It will be dynamic. In next series I am preparing the user will be able to increase the number of CCS engines he wants to use.

Quoted 5 lines
Quoted 5 lines

Similar as we do for gsc which uses I915_NO_UABI_CLASS, although for ccs you can choose a different approach, whatever is more elegant.

That is also needed for i915->engine_uabi_class_count to be right, so userspace stats which rely on it are correct.

Oh yes. Will update it.

Quoted 5 lines

I later realized it is more than that - everything that uses intel_engine_lookup_user to look up class instance passed in from userspace relies on the engine not being on the user list otherwise userspace could bypass the fact engine query does not list it. Like PMU, Perf/POA, context engine map and SSEU context query.

Correct, will look into that, thank you!

Andi

#12 lore raw

Re: [PATCH 2/2] drm/i915/gt: Set default CCS mode '1'

Quoted 32 lines · Andi Shyti

Hi Tvrtko,

Quoted 2 lines · Tvrtko Ursulin
Quoted 1 line · Tvrtko Ursulin

On 15/02/2024 13:59, Andi Shyti wrote:

...

Quoted 15 lines
Quoted 15 lines
Quoted 15 lines

+/*
+ * Exclude unavailable engines.
+ *
+ * Only the first CCS engine is utilized due to the disabling of CCS auto load
+ * balancing. As a result, all CCS engines operate collectively, functioning
+ * essentially as a single CCS engine, hence the count of active CCS engines is
+ * considered '1'.
+ * Currently, this applies to platforms with more than one CCS engine,
+ * specifically DG2.
+ */
+#define for_each_available_uabi_engine(engine__, i915__) \
+    for_each_uabi_engine(engine__, i915__) \

Quoted 8 lines
Quoted 8 lines
Quoted 5 lines

+        if ((IS_DG2(i915__)) && \
+            ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+            ((engine__)->uabi_instance)) { } \
+        else
+

If you don't want userspace to see some engines, just don't add them to the uabi list in intel_engines_driver_register or thereabouts?

Quoted 2 lines

It will be dynamic. In next series I am preparing the user will be able to increase the number of CCS engines he wants to use.

Oh tricky and new. Does it need to be at runtime or could be boot time?

If you are aiming to make the static single CCS only into the 6.9 release, and you feel running out of time, you could always do a simple solution for now. The one I mentioned of simply not registering on the uabi list. Then you can refine more leisurely for the next release.

Regards,

Tvrtko

Quoted 18 lines
Quoted 6 lines
Quoted 6 lines

Similar as we do for gsc which uses I915_NO_UABI_CLASS, although for ccs you can choose a different approach, whatever is more elegant.

That is also needed for i915->engine_uabi_class_count to be right, so userspace stats which rely on it are correct.

Oh yes. Will update it.

Quoted 5 lines

I later realized it is more than that - everything that uses intel_engine_lookup_user to look up class instance passed in from userspace relies on the engine not being on the user list otherwise userspace could bypass the fact engine query does not list it. Like PMU, Perf/POA, context engine map and SSEU context query.

Correct, will look into that, thank you!

Andi

author
#13 lore raw

Re: [PATCH 2/2] drm/i915/gt: Set default CCS mode '1'

Quoted 31 lines · Tvrtko Ursulin
Quoted 30 lines · Andi Shyti
Quoted 2 lines · Tvrtko Ursulin
Quoted 1 line · Tvrtko Ursulin

On 15/02/2024 13:59, Andi Shyti wrote:

...

Quoted 23 lines
Quoted 23 lines
Quoted 13 lines

+/*
+ * Exclude unavailable engines.
+ *
+ * Only the first CCS engine is utilized due to the disabling of CCS auto load
+ * balancing. As a result, all CCS engines operate collectively, functioning
+ * essentially as a single CCS engine, hence the count of active CCS engines is
+ * considered '1'.
+ * Currently, this applies to platforms with more than one CCS engine,
+ * specifically DG2.
+ */

drivers/gpu/drm/i915/i915_drv.h static inline struct intel_gt *to_gt(const struct drm_i915_private *i915) · line 415

Quoted 7 lines
drivers/gpu/drm/i915/i915_drv.h +7 -0
+#define for_each_available_uabi_engine(engine__, i915__) \
+    for_each_uabi_engine(engine__, i915__) \
+        if ((IS_DG2(i915__)) && \
+            ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+            ((engine__)->uabi_instance)) { } \
+        else
+

If you don't want userspace to see some engines, just don't add them to the uabi list in intel_engines_driver_register or thereabouts?

Quoted 4 lines
Quoted 2 lines

It will be dynamic. In next series I am preparing the user will be able to increase the number of CCS engines he wants to use.

Oh tricky and new. Does it need to be at runtime or could be boot time?

At boot time the CCS mode has to be set to '1', i.e. only one CCS will be visible to the user. Then, during the normal execution of the driver, the user can decide to change the mode and therefore we would need to expose more than one CCS engine.

Quoted 4 lines

If you are aiming to make the static single CCS only into the 6.9 release, and you feel running out of time, you could always do a simple solution for now. The one I mentioned of simply not registering on the uabi list. Then you can refine more leisurely for the next release.

Thanks. I started working on a dynamic rebuilt of the uabi_engines, but in this series it wouldn't fit.

I will add the limitation during the list creation.

Thanks a lot,
Andi

#14 lore raw

✗ Fi.CI.CHECKPATCH: warning for Disable automatic load CCS load balancing

In reply to Andi Shyti
== Series Details ==

== Series Details ==

Series: Disable automatic load CCS load balancing
URL : https://patchwork.freedesktop.org/series/129951/
State : warning

== Summary ==

Error: dim checkpatch failed
36e5f8a455e7 drm/i915/gt: Disable HW load balancing for CCS
f1bfa29b3219 drm/i915/gt: Set default CCS mode '1'
-:80: ERROR:COMPLEX_MACRO: Macros with complex values should be enclosed in parentheses #80: FILE: drivers/gpu/drm/i915/i915_drv.h:409:
+#define for_each_available_uabi_engine(engine__, i915__) \
+ for_each_uabi_engine(engine__, i915__) \
+ if ((IS_DG2(i915__)) && \
+ ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+ ((engine__)->uabi_instance)) { } \
+ else

-:80: CHECK:MACRO_ARG_REUSE: Macro argument reuse 'engine__' - possible side-effects? #80: FILE: drivers/gpu/drm/i915/i915_drv.h:409:
+#define for_each_available_uabi_engine(engine__, i915__) \
+ for_each_uabi_engine(engine__, i915__) \
+ if ((IS_DG2(i915__)) && \
+ ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+ ((engine__)->uabi_instance)) { } \
+ else

-:80: CHECK:MACRO_ARG_REUSE: Macro argument reuse 'i915__' - possible side-effects? #80: FILE: drivers/gpu/drm/i915/i915_drv.h:409:
+#define for_each_available_uabi_engine(engine__, i915__) \
+ for_each_uabi_engine(engine__, i915__) \
+ if ((IS_DG2(i915__)) && \
+ ((engine__)->uabi_class == I915_ENGINE_CLASS_COMPUTE) && \
+ ((engine__)->uabi_instance)) { } \
+ else

-:82: ERROR:TRAILING_STATEMENTS: trailing statements should be on next line #82: FILE: drivers/gpu/drm/i915/i915_drv.h:411:
+ if ((IS_DG2(i915__)) && \
[...]
+ ((engine__)->uabi_instance)) { } \

-:98: CHECK:LINE_SPACING: Please don't use multiple blank lines #98: FILE: drivers/gpu/drm/i915/i915_query.c:127:

+

total: 2 errors, 0 warnings, 3 checks, 77 lines checked

#16 lore raw

✗ Fi.CI.BAT: failure for Disable automatic load CCS load balancing

In reply to Andi Shyti
== Series Details ==

== Series Details ==

Series: Disable automatic load CCS load balancing
URL : https://patchwork.freedesktop.org/series/129951/
State : failure

== Summary ==

CI Bug Log - changes from CI_DRM_14278 -> Patchwork_129951v1
====================================================

Summary
-------

**FAILURE**

Serious unknown changes coming with Patchwork_129951v1 absolutely need to be verified manually.

If you think the reported changes have nothing to do with the changes
introduced in Patchwork_129951v1, please notify your bug team ([email protected]) to allow them to document this new failure mode, which will reduce false positives in CI.

External URL: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/index.html

Participating hosts (36 -> 35)
------------------------------

Additional (1): bat-mtlp-8
Missing (2): bat-kbl-2 fi-snb-2520m

Possible new issues
-------------------

Here are the unknown changes that may have been introduced in Patchwork_129951v1:

### IGT changes ###

#### Possible regressions ####

* igt@i915_module_load@load:
- fi-skl-6600u: [PASS][1] -> [ABORT][2]
[1]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-skl-6600u/igt@[email protected]
[2]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-skl-6600u/igt@[email protected]
- fi-glk-j4005: [PASS][3] -> [ABORT][4]
[3]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-glk-j4005/igt@[email protected]
[4]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-glk-j4005/igt@[email protected]
- fi-skl-guc: [PASS][5] -> [ABORT][6]
[5]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-skl-guc/igt@[email protected]
[6]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-skl-guc/igt@[email protected]
- fi-kbl-7567u: [PASS][7] -> [ABORT][8]
[7]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-kbl-7567u/igt@[email protected]
[8]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-kbl-7567u/igt@[email protected]
- fi-cfl-8700k: [PASS][9] -> [ABORT][10]
[9]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-cfl-8700k/igt@[email protected]
[10]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-cfl-8700k/igt@[email protected]
- fi-bsw-nick: [PASS][11] -> [ABORT][12]
[11]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-bsw-nick/igt@[email protected]
[12]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-bsw-nick/igt@[email protected]
- fi-cfl-guc: [PASS][13] -> [ABORT][14]
[13]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-cfl-guc/igt@[email protected]
[14]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-cfl-guc/igt@[email protected]
- fi-kbl-x1275: [PASS][15] -> [ABORT][16]
[15]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-kbl-x1275/igt@[email protected]
[16]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-kbl-x1275/igt@[email protected]
- fi-cfl-8109u: [PASS][17] -> [ABORT][18]
[17]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-cfl-8109u/igt@[email protected]
[18]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-cfl-8109u/igt@[email protected]
- fi-ivb-3770: [PASS][19] -> [ABORT][20]
[19]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-ivb-3770/igt@[email protected]
[20]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-ivb-3770/igt@[email protected]
- fi-kbl-guc: [PASS][21] -> [ABORT][22]
[21]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-kbl-guc/igt@[email protected]
[22]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-kbl-guc/igt@[email protected]

* igt@i915_selftest@live@client:
- fi-elk-e7500: [PASS][23] -> [DMESG-WARN][24] +42 other tests dmesg-warn
[23]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-elk-e7500/igt@i915_selftest@[email protected]
[24]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-elk-e7500/igt@i915_selftest@[email protected]

* igt@i915_selftest@live@coherency:
- bat-jsl-3: [PASS][25] -> [DMESG-WARN][26] +41 other tests dmesg-warn
[25]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/bat-jsl-3/igt@i915_selftest@[email protected]
[26]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-jsl-3/igt@i915_selftest@[email protected]

* igt@i915_selftest@live@gt_contexts:
- fi-ilk-650: [PASS][27] -> [DMESG-WARN][28] +42 other tests dmesg-warn
[27]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-ilk-650/igt@i915_selftest@live@gt_contexts.html
[28]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-ilk-650/igt@i915_selftest@live@gt_contexts.html

* igt@i915_selftest@live@gt_pm:
- bat-jsl-1: [PASS][29] -> [DMESG-WARN][30] +41 other tests dmesg-warn
[29]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/bat-jsl-1/igt@i915_selftest@live@gt_pm.html
[30]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-jsl-1/igt@i915_selftest@live@gt_pm.html

#### Suppressed ####

The following results come from untrusted machines, tests, or statuses. They do not affect the overall result.

* igt@gem_exec_fence@basic-busy@rcs0:
- {bat-arls-1}: [PASS][31] -> [DMESG-WARN][32]
[31]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/bat-arls-1/igt@gem_exec_fence@[email protected]
[32]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-arls-1/igt@gem_exec_fence@[email protected]

Known issues
------------

Here are the changes found in Patchwork_129951v1 that come from known issues:

### CI changes ###

#### Issues hit ####

* boot:
- fi-apl-guc: [PASS][33] -> [FAIL][34] ([i915#8293])
[33]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/fi-apl-guc/boot.html
[34]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/fi-apl-guc/boot.html

### IGT changes ###

#### Issues hit ####

* igt@debugfs_test@basic-hwmon:
- bat-mtlp-8: NOTRUN -> [SKIP][35] ([i915#9318])
[35]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@gem_lmem_swapping@verify-random:
- bat-mtlp-8: NOTRUN -> [SKIP][36] ([i915#4613]) +3 other tests skip
[36]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@gem_mmap@basic:
- bat-mtlp-8: NOTRUN -> [SKIP][37] ([i915#4083])
[37]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@gem_mmap_gtt@basic:
- bat-mtlp-8: NOTRUN -> [SKIP][38] ([i915#4077]) +2 other tests skip
[38]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@gem_render_tiled_blits@basic:
- bat-mtlp-8: NOTRUN -> [SKIP][39] ([i915#4079]) +1 other test skip
[39]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@i915_pm_rps@basic-api:
- bat-mtlp-8: NOTRUN -> [SKIP][40] ([i915#6621])
[40]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@kms_addfb_basic@addfb25-y-tiled-small-legacy:
- bat-mtlp-8: NOTRUN -> [SKIP][41] ([i915#5190])
[41]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@kms_addfb_basic@basic-y-tiled-legacy:
- bat-mtlp-8: NOTRUN -> [SKIP][42] ([i915#4212]) +8 other tests skip
[42]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@kms_cursor_legacy@basic-busy-flip-before-cursor-legacy:
- bat-mtlp-8: NOTRUN -> [SKIP][43] ([i915#4213]) +1 other test skip
[43]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@kms_dsc@dsc-basic:
- bat-mtlp-8: NOTRUN -> [SKIP][44] ([i915#3555] / [i915#3840] / [i915#9159])
[44]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@kms_force_connector_basic@force-load-detect:
- bat-mtlp-8: NOTRUN -> [SKIP][45] ([fdo#109285])
[45]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@kms_force_connector_basic@prune-stale-modes:
- bat-mtlp-8: NOTRUN -> [SKIP][46] ([i915#5274])
[46]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@kms_setmode@basic-clone-single-crtc:
- bat-mtlp-8: NOTRUN -> [SKIP][47] ([i915#3555] / [i915#8809])
[47]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@prime_vgem@basic-fence-mmap:
- bat-mtlp-8: NOTRUN -> [SKIP][48] ([i915#3708] / [i915#4077]) +1 other test skip
[48]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

* igt@prime_vgem@basic-fence-read:
- bat-mtlp-8: NOTRUN -> [SKIP][49] ([i915#3708]) +2 other tests skip
[49]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-mtlp-8/igt@[email protected]

#### Possible fixes ####

* igt@gem_exec_create@basic@smem:
- {bat-arls-1}: [DMESG-WARN][50] ([i915#10194]) -> [PASS][51]
[50]: https://intel-gfx-ci.01.org/tree/drm-tip/CI_DRM_14278/bat-arls-1/igt@gem_exec_create@[email protected]
[51]: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/bat-arls-1/igt@gem_exec_create@[email protected]

{name}: This element is suppressed. This means it is ignored when computing
the status of the difference (SUCCESS, WARNING, or FAILURE).

[fdo#109285]: https://bugs.freedesktop.org/show_bug.cgi?id=109285
[i915#10194]: https://gitlab.freedesktop.org/drm/intel/issues/10194
[i915#3555]: https://gitlab.freedesktop.org/drm/intel/issues/3555
[i915#3708]: https://gitlab.freedesktop.org/drm/intel/issues/3708
[i915#3840]: https://gitlab.freedesktop.org/drm/intel/issues/3840
[i915#4077]: https://gitlab.freedesktop.org/drm/intel/issues/4077
[i915#4079]: https://gitlab.freedesktop.org/drm/intel/issues/4079
[i915#4083]: https://gitlab.freedesktop.org/drm/intel/issues/4083
[i915#4212]: https://gitlab.freedesktop.org/drm/intel/issues/4212
[i915#4213]: https://gitlab.freedesktop.org/drm/intel/issues/4213
[i915#4613]: https://gitlab.freedesktop.org/drm/intel/issues/4613
[i915#5190]: https://gitlab.freedesktop.org/drm/intel/issues/5190
[i915#5274]: https://gitlab.freedesktop.org/drm/intel/issues/5274
[i915#6621]: https://gitlab.freedesktop.org/drm/intel/issues/6621
[i915#8293]: https://gitlab.freedesktop.org/drm/intel/issues/8293
[i915#8809]: https://gitlab.freedesktop.org/drm/intel/issues/8809
[i915#9159]: https://gitlab.freedesktop.org/drm/intel/issues/9159
[i915#9318]: https://gitlab.freedesktop.org/drm/intel/issues/9318
[i915#9688]: https://gitlab.freedesktop.org/drm/intel/issues/9688

Build changes
-------------

* Linux: CI_DRM_14278 -> Patchwork_129951v1

CI-20190529: 20190529
CI_DRM_14278: 000df4b23820dc3866d8c92c228c778ef33bf396 @ git://anongit.freedesktop.org/gfx-ci/linux
IGT_7714: 7714
Patchwork_129951v1: 000df4b23820dc3866d8c92c228c778ef33bf396 @ git://anongit.freedesktop.org/gfx-ci/linux

### Linux commits

08e0f187cab5 drm/i915/gt: Set default CCS mode '1' c21b8eb46264 drm/i915/gt: Disable HW load balancing for CCS

== Logs ==

For more details see: https://intel-gfx-ci.01.org/tree/drm-tip/Patchwork_129951v1/index.html