[PATCH 6/8] drm/i915: reprogram NOA muxes on context switch when using perf

[Lionel Landwerlin <lionel.g.landwerlin@intel.com>]

If some of the contexts submitting workloads to the GPU have been
configured to shutdown slices/subslices, we might loose the NOA
configurations written in the NOA muxes. We need to reprogram them at
context switch.

Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
---
 drivers/gpu/drm/i915/i915_drv.h  |  2 +
 drivers/gpu/drm/i915/i915_perf.c | 92 +++++++++++++++++++++++++++++---
 drivers/gpu/drm/i915/intel_lrc.c | 71 +++++++++++++++++++++---
 drivers/gpu/drm/i915/intel_lrc.h |  1 +
 4 files changed, 153 insertions(+), 13 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index fdf71164ee24..b15f1fa4453a 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -3263,6 +3263,8 @@ int i915_perf_remove_config_ioctl(struct drm_device *dev, void *data,
 void i915_oa_init_reg_state(struct intel_engine_cs *engine,
 			    struct i915_gem_context *ctx,
 			    uint32_t *reg_state);
+u32 i915_oa_get_perctx_bb_size(struct intel_engine_cs *engine);
+u32 *i915_oa_emit_perctx_bb(struct intel_engine_cs *engine, u32 *batch);
 
 /* i915_gem_evict.c */
 int __must_check i915_gem_evict_something(struct i915_address_space *vm,
diff --git a/drivers/gpu/drm/i915/i915_perf.c b/drivers/gpu/drm/i915/i915_perf.c
index 2fc9c85a0d99..d1598f54e63b 100644
--- a/drivers/gpu/drm/i915/i915_perf.c
+++ b/drivers/gpu/drm/i915/i915_perf.c
@@ -1752,6 +1752,71 @@ static int gen8_emit_oa_config(struct i915_request *rq,
 	return 0;
 }
 
+#define MAX_LRI_SIZE (125U)
+
+u32 i915_oa_get_perctx_bb_size(struct intel_engine_cs *engine)
+{
+	struct drm_i915_private *dev_priv = engine->i915;
+	struct i915_perf_stream *stream = dev_priv->perf.oa.exclusive_stream;
+	struct i915_oa_config *oa_config;
+	u32 n_lri;
+
+	/* We only care about RCS. */
+	if (engine->id != RCS)
+		return 0;
+
+	/* Perf not supported. */
+	if (!dev_priv->perf.initialized)
+		return 0;
+
+	/* OA not currently configured. */
+	if (!stream)
+		return 0;
+
+	oa_config = stream->oa_config;
+
+	/* Very unlikely but possible that we have no muxes to configure. */
+	if (!oa_config->mux_regs_len)
+		return 0;
+
+	n_lri = (oa_config->mux_regs_len / MAX_LRI_SIZE) +
+		(oa_config->mux_regs_len % MAX_LRI_SIZE) != 0;
+
+	/* Return the size of MI_LOAD_REGISTER_IMMs + PIPE_CONTROL . */
+	return n_lri * 4 + oa_config->mux_regs_len * 8 + 24;
+}
+
+u32 *i915_oa_emit_perctx_bb(struct intel_engine_cs *engine, u32 *batch)
+{
+	struct drm_i915_private *dev_priv = engine->i915;
+	struct i915_oa_config *oa_config;
+	u32 i, n_loaded_regs;
+
+	if (i915_oa_get_perctx_bb_size(engine) == 0)
+		return batch;
+
+	oa_config = dev_priv->perf.oa.exclusive_stream->oa_config;
+
+	n_loaded_regs = 0;
+	for (i = 0; i < oa_config->mux_regs_len; i++) {
+		if ((n_loaded_regs % MAX_LRI_SIZE) == 0) {
+			u32 n_lri = min(oa_config->mux_regs_len - n_loaded_regs,
+					MAX_LRI_SIZE);
+			*batch++ = MI_LOAD_REGISTER_IMM(n_lri);
+		}
+
+		*batch++ = i915_mmio_reg_offset(oa_config->mux_regs[i].addr);
+		*batch++ = oa_config->mux_regs[i].value;
+		n_loaded_regs++;
+	}
+
+	batch = gen8_emit_pipe_control(batch,
+				       PIPE_CONTROL_MMIO_WRITE,
+				       0);
+
+	return batch;
+}
+
 static int gen8_switch_to_updated_kernel_context(struct drm_i915_private *dev_priv,
 						 const struct i915_oa_config *oa_config)
 {
@@ -1829,7 +1894,7 @@ static int gen8_configure_all_contexts(struct drm_i915_private *dev_priv,
 	/* Switch away from any user context. */
 	ret = gen8_switch_to_updated_kernel_context(dev_priv, oa_config);
 	if (ret)
-		goto out;
+		return ret;
 
 	/*
 	 * The OA register config is setup through the context image. This image
@@ -1846,7 +1911,16 @@ static int gen8_configure_all_contexts(struct drm_i915_private *dev_priv,
 	 */
 	ret = i915_gem_wait_for_idle(dev_priv, wait_flags);
 	if (ret)
-		goto out;
+		return ret;
+
+	/*
+	 * Reload the workaround batchbuffer to include NOA muxes
+	 * reprogramming on context-switch, so we don't loose configurations
+	 * after switch-from a context with disabled slices/subslices.
+	 */
+	ret = logical_render_ring_reload_wa_bb(dev_priv->engine[RCS]);
+	if (ret)
+		return ret;
 
 	/* Update all contexts now that we've stalled the submission. */
 	list_for_each_entry(ctx, &dev_priv->contexts.list, link) {
@@ -1858,10 +1932,8 @@ static int gen8_configure_all_contexts(struct drm_i915_private *dev_priv,
 			continue;
 
 		regs = i915_gem_object_pin_map(ce->state->obj, I915_MAP_WB);
-		if (IS_ERR(regs)) {
-			ret = PTR_ERR(regs);
-			goto out;
-		}
+		if (IS_ERR(regs))
+			return PTR_ERR(regs);
 
 		ce->state->obj->mm.dirty = true;
 		regs += LRC_STATE_PN * PAGE_SIZE / sizeof(*regs);
@@ -1871,7 +1943,6 @@ static int gen8_configure_all_contexts(struct drm_i915_private *dev_priv,
 		i915_gem_object_unpin_map(ce->state->obj);
 	}
 
- out:
 	return ret;
 }
 
@@ -2213,6 +2284,13 @@ static int i915_oa_stream_init(struct i915_perf_stream *stream,
 
 	dev_priv->perf.oa.exclusive_stream = stream;
 
+	ret = dev_priv->perf.oa.ops.enable_metric_set(dev_priv,
+						      stream->oa_config);
+	if (ret)
+		goto err_enable;
+
+	stream->ops = &i915_oa_stream_ops;
+
 	mutex_unlock(&dev_priv->drm.struct_mutex);
 
 	return 0;
diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 7a5efab3e4fb..a0f72fcda0d9 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -169,6 +169,8 @@ static void execlists_init_reg_state(u32 *reg_state,
 				     struct i915_gem_context *ctx,
 				     struct intel_engine_cs *engine,
 				     struct intel_ring *ring);
+static void execlists_init_reg_state_wa_bb(u32 *reg_state,
+					   struct intel_engine_cs *engine);
 
 static inline struct i915_priolist *to_priolist(struct rb_node *rb)
 {
@@ -1584,16 +1586,28 @@ gen10_init_indirectctx_bb(struct intel_engine_cs *engine, u32 *batch)
 	return batch;
 }
 
-#define CTX_WA_BB_OBJ_SIZE (PAGE_SIZE)
+static u32 *gen_init_perctx_bb(struct intel_engine_cs *engine, u32 *batch)
+{
+	batch = i915_oa_emit_perctx_bb(engine, batch);
+	*batch++ = MI_BATCH_BUFFER_END;
+
+	return batch;
+}
+
+/* Reserve a minimum of 200 dwords for indirect bb */
+#define CTX_WA_BB_MIN_DWORDS (200)
 
 static int lrc_setup_wa_ctx(struct intel_engine_cs *engine,
 			    struct i915_ctx_workarounds *wa_ctx)
 {
 	struct drm_i915_gem_object *obj;
 	struct i915_vma *vma;
+	u32 n_pages = DIV_ROUND_UP(i915_oa_get_perctx_bb_size(engine) +
+				   4 * CTX_WA_BB_MIN_DWORDS,
+				   PAGE_SIZE);
 	int err;
 
-	obj = i915_gem_object_create(engine->i915, CTX_WA_BB_OBJ_SIZE);
+	obj = i915_gem_object_create(engine->i915, n_pages * PAGE_SIZE);
 	if (IS_ERR(obj))
 		return PTR_ERR(obj);
 
@@ -1639,15 +1653,15 @@ static int intel_init_workaround_bb(struct intel_engine_cs *engine,
 	switch (INTEL_GEN(engine->i915)) {
 	case 10:
 		wa_bb_fn[0] = gen10_init_indirectctx_bb;
-		wa_bb_fn[1] = NULL;
+		wa_bb_fn[1] = gen_init_perctx_bb;
 		break;
 	case 9:
 		wa_bb_fn[0] = gen9_init_indirectctx_bb;
-		wa_bb_fn[1] = NULL;
+		wa_bb_fn[1] = gen_init_perctx_bb;
 		break;
 	case 8:
 		wa_bb_fn[0] = gen8_init_indirectctx_bb;
-		wa_bb_fn[1] = NULL;
+		wa_bb_fn[1] = gen_init_perctx_bb;
 		break;
 	default:
 		MISSING_CASE(INTEL_GEN(engine->i915));
@@ -1680,7 +1694,7 @@ static int intel_init_workaround_bb(struct intel_engine_cs *engine,
 		wa_bb[i]->size = batch_ptr - (batch + wa_bb[i]->offset);
 	}
 
-	BUG_ON(batch_ptr - batch > CTX_WA_BB_OBJ_SIZE);
+	BUG_ON(batch_ptr - batch > wa_ctx->vma->obj->base.size);
 
 	kunmap_atomic(batch);
 	if (ret)
@@ -2321,6 +2335,51 @@ int logical_render_ring_init(struct intel_engine_cs *engine)
 	return logical_ring_init(engine);
 }
 
+int logical_render_ring_reload_wa_bb(struct intel_engine_cs *engine)
+{
+	struct drm_i915_private *dev_priv = engine->i915;
+	struct i915_ctx_workarounds new_wa_ctx;
+	struct i915_gem_context *ctx;
+	int ret;
+
+	if (WARN_ON(engine->id != RCS))
+		return -EINVAL;
+
+	memset(&new_wa_ctx, 0, sizeof(new_wa_ctx));
+	ret = intel_init_workaround_bb(engine, &new_wa_ctx);
+	if (ret)
+		return ret;
+
+	if (engine->wa_ctx.vma)
+		lrc_destroy_wa_ctx(engine);
+
+	memcpy(&engine->wa_ctx, &new_wa_ctx, sizeof(engine->wa_ctx));
+
+	list_for_each_entry(ctx, &dev_priv->contexts.list, link) {
+		struct intel_context *ce = &ctx->engine[RCS];
+		u32 *regs;
+
+		/* Settings will be set upon first use. */
+		if (!ce->state)
+			continue;
+
+		regs = i915_gem_object_pin_map(ce->state->obj, I915_MAP_WB);
+		if (IS_ERR(regs)) {
+			ret = PTR_ERR(regs);
+			break;
+		}
+
+		ce->state->obj->mm.dirty = true;
+		regs += LRC_STATE_PN * PAGE_SIZE / sizeof(*regs);
+
+		execlists_init_reg_state_wa_bb(regs, engine);
+
+		i915_gem_object_unpin_map(ce->state->obj);
+	}
+
+	return ret;
+}
+
 int logical_xcs_ring_init(struct intel_engine_cs *engine)
 {
 	logical_ring_setup(engine);
diff --git a/drivers/gpu/drm/i915/intel_lrc.h b/drivers/gpu/drm/i915/intel_lrc.h
index 59d7b86012e9..d91d69a17206 100644
--- a/drivers/gpu/drm/i915/intel_lrc.h
+++ b/drivers/gpu/drm/i915/intel_lrc.h
@@ -71,6 +71,7 @@ enum {
 /* Logical Rings */
 void intel_logical_ring_cleanup(struct intel_engine_cs *engine);
 int logical_render_ring_init(struct intel_engine_cs *engine);
+int logical_render_ring_reload_wa_bb(struct intel_engine_cs *engine);
 int logical_xcs_ring_init(struct intel_engine_cs *engine);
 
 /* Logical Ring Contexts */
-- 
2.17.0

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx