drm/i915: Integrate GuC-based command submission

GuC-based submission is mostly the same as execlist mode, up to
intel_logical_ring_advance_and_submit(), where the context being
dispatched would be added to the execlist queue; at this point
we submit the context to the GuC backend instead.

There are, however, a few other changes also required, notably:
1.  Contexts must be pinned at GGTT addresses accessible by the GuC
    i.e. NOT in the range [0..WOPCM_SIZE), so we have to add the
    PIN_OFFSET_BIAS flag to the relevant GGTT-pinning calls.

2.  The GuC's TLB must be invalidated after a context is pinned at
    a new GGTT address.

3.  GuC firmware uses the one page before Ring Context as shared data.
    Therefore, whenever driver wants to get base address of LRC, we
    will offset one page for it. LRC_PPHWSP_PN is defined as the page
    number of LRCA.

4.  In the work queue used to pass requests to the GuC, the GuC
    firmware requires the ring-tail-offset to be represented as an
    11-bit value, expressed in QWords. Therefore, the ringbuffer
    size must be reduced to the representable range (4 pages).

v2:
    Defer adding #defines until needed [Chris Wilson]
    Rationalise type declarations [Chris Wilson]

v4:
    Squashed kerneldoc patch into here [Daniel Vetter]

v5:
    Update request->tail in code common to both GuC and execlist modes.
    Add a private version of lr_context_update(), as sharing the
        execlist version leads to race conditions when the CPU and
        the GuC both update TAIL in the context image.
    Conversion of error-captured HWS page to string must account
        for offset from start of object to actual HWS (LRC_PPHWSP_PN).

Issue: VIZ-4884
Signed-off-by: Alex Dai <yu.dai@intel.com>
Signed-off-by: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Tom O'Rourke <Tom.O'Rourke@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 38 insertions, 17 deletions

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index f3411f835a5a..e77b6b0d44d9 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -263,7 +263,8 @@ int intel_sanitize_enable_execlists(struct drm_device *dev, int enable_execlists
  */
 u32 intel_execlists_ctx_id(struct drm_i915_gem_object *ctx_obj)
 {
-	u32 lrca = i915_gem_obj_ggtt_offset(ctx_obj);
+	u32 lrca = i915_gem_obj_ggtt_offset(ctx_obj) +
+			LRC_PPHWSP_PN * PAGE_SIZE;
 
 	/* LRCA is required to be 4K aligned so the more significant 20 bits
 	 * are globally unique */
@@ -276,7 +277,8 @@ uint64_t intel_lr_context_descriptor(struct intel_context *ctx,
 	struct drm_device *dev = ring->dev;
 	struct drm_i915_gem_object *ctx_obj = ctx->engine[ring->id].state;
 	uint64_t desc;
-	uint64_t lrca = i915_gem_obj_ggtt_offset(ctx_obj);
+	uint64_t lrca = i915_gem_obj_ggtt_offset(ctx_obj) +
+			LRC_PPHWSP_PN * PAGE_SIZE;
 
 	WARN_ON(lrca & 0xFFFFFFFF00000FFFULL);
 
@@ -350,7 +352,7 @@ static int execlists_update_context(struct drm_i915_gem_request *rq)
 	WARN_ON(!i915_gem_obj_is_pinned(ctx_obj));
 	WARN_ON(!i915_gem_obj_is_pinned(rb_obj));
 
-	page = i915_gem_object_get_page(ctx_obj, 1);
+	page = i915_gem_object_get_page(ctx_obj, LRC_STATE_PN);
 	reg_state = kmap_atomic(page);
 
 	reg_state[CTX_RING_TAIL+1] = rq->tail;
@@ -548,8 +550,6 @@ static int execlists_context_queue(struct drm_i915_gem_request *request)
 
 	i915_gem_request_reference(request);
 
-	request->tail = request->ringbuf->tail;
-
 	spin_lock_irq(&ring->execlist_lock);
 
 	list_for_each_entry(cursor, &ring->execlist_queue, execlist_link)
@@ -702,13 +702,19 @@ static void
 intel_logical_ring_advance_and_submit(struct drm_i915_gem_request *request)
 {
 	struct intel_engine_cs *ring = request->ring;
+	struct drm_i915_private *dev_priv = request->i915;
 
 	intel_logical_ring_advance(request->ringbuf);
 
+	request->tail = request->ringbuf->tail;
+
 	if (intel_ring_stopped(ring))
 		return;
 
-	execlists_context_queue(request);
+	if (dev_priv->guc.execbuf_client)
+		i915_guc_submit(dev_priv->guc.execbuf_client, request);
+	else
+		execlists_context_queue(request);
 }
 
 static void __wrap_ring_buffer(struct intel_ringbuffer *ringbuf)
@@ -998,6 +1004,7 @@ int logical_ring_flush_all_caches(struct drm_i915_gem_request *req)
 
 static int intel_lr_context_pin(struct drm_i915_gem_request *rq)
 {
+	struct drm_i915_private *dev_priv = rq->i915;
 	struct intel_engine_cs *ring = rq->ring;
 	struct drm_i915_gem_object *ctx_obj = rq->ctx->engine[ring->id].state;
 	struct intel_ringbuffer *ringbuf = rq->ringbuf;
@@ -1005,14 +1012,18 @@ static int intel_lr_context_pin(struct drm_i915_gem_request *rq)
 
 	WARN_ON(!mutex_is_locked(&ring->dev->struct_mutex));
 	if (rq->ctx->engine[ring->id].pin_count++ == 0) {
-		ret = i915_gem_obj_ggtt_pin(ctx_obj,
-				GEN8_LR_CONTEXT_ALIGN, 0);
+		ret = i915_gem_obj_ggtt_pin(ctx_obj, GEN8_LR_CONTEXT_ALIGN,
+				PIN_OFFSET_BIAS | GUC_WOPCM_TOP);
 		if (ret)
 			goto reset_pin_count;
 
 		ret = intel_pin_and_map_ringbuffer_obj(ring->dev, ringbuf);
 		if (ret)
 			goto unpin_ctx_obj;
+
+		/* Invalidate GuC TLB. */
+		if (i915.enable_guc_submission)
+			I915_WRITE(GEN8_GTCR, GEN8_GTCR_INVALIDATE);
 	}
 
 	return ret;
@@ -2137,7 +2148,7 @@ populate_lr_context(struct intel_context *ctx, struct drm_i915_gem_object *ctx_o
 
 	/* The second page of the context object contains some fields which must
 	 * be set up prior to the first execution. */
-	page = i915_gem_object_get_page(ctx_obj, 1);
+	page = i915_gem_object_get_page(ctx_obj, LRC_STATE_PN);
 	reg_state = kmap_atomic(page);
 
 	/* A context is actually a big batch buffer with several MI_LOAD_REGISTER_IMM
@@ -2307,12 +2318,13 @@ static void lrc_setup_hardware_status_page(struct intel_engine_cs *ring,
 		struct drm_i915_gem_object *default_ctx_obj)
 {
 	struct drm_i915_private *dev_priv = ring->dev->dev_private;
+	struct page *page;
 
-	/* The status page is offset 0 from the default context object
-	 * in LRC mode. */
-	ring->status_page.gfx_addr = i915_gem_obj_ggtt_offset(default_ctx_obj);
-	ring->status_page.page_addr =
-			kmap(sg_page(default_ctx_obj->pages->sgl));
+	/* The HWSP is part of the default context object in LRC mode. */
+	ring->status_page.gfx_addr = i915_gem_obj_ggtt_offset(default_ctx_obj)
+			+ LRC_PPHWSP_PN * PAGE_SIZE;
+	page = i915_gem_object_get_page(default_ctx_obj, LRC_PPHWSP_PN);
+	ring->status_page.page_addr = kmap(page);
 	ring->status_page.obj = default_ctx_obj;
 
 	I915_WRITE(RING_HWS_PGA(ring->mmio_base),
@@ -2338,6 +2350,7 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
 {
 	const bool is_global_default_ctx = (ctx == ring->default_context);
 	struct drm_device *dev = ring->dev;
+	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct drm_i915_gem_object *ctx_obj;
 	uint32_t context_size;
 	struct intel_ringbuffer *ringbuf;
@@ -2348,6 +2361,9 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
 
 	context_size = round_up(get_lr_context_size(ring), 4096);
 
+	/* One extra page as the sharing data between driver and GuC */
+	context_size += PAGE_SIZE * LRC_PPHWSP_PN;
+
 	ctx_obj = i915_gem_alloc_object(dev, context_size);
 	if (!ctx_obj) {
 		DRM_DEBUG_DRIVER("Alloc LRC backing obj failed.\n");
@@ -2355,13 +2371,18 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
 	}
 
 	if (is_global_default_ctx) {
-		ret = i915_gem_obj_ggtt_pin(ctx_obj, GEN8_LR_CONTEXT_ALIGN, 0);
+		ret = i915_gem_obj_ggtt_pin(ctx_obj, GEN8_LR_CONTEXT_ALIGN,
+				PIN_OFFSET_BIAS | GUC_WOPCM_TOP);
 		if (ret) {
 			DRM_DEBUG_DRIVER("Pin LRC backing obj failed: %d\n",
 					ret);
 			drm_gem_object_unreference(&ctx_obj->base);
 			return ret;
 		}
+
+		/* Invalidate GuC TLB. */
+		if (i915.enable_guc_submission)
+			I915_WRITE(GEN8_GTCR, GEN8_GTCR_INVALIDATE);
 	}
 
 	ringbuf = kzalloc(sizeof(*ringbuf), GFP_KERNEL);
@@ -2374,7 +2395,7 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
 
 	ringbuf->ring = ring;
 
-	ringbuf->size = 32 * PAGE_SIZE;
+	ringbuf->size = 4 * PAGE_SIZE;
 	ringbuf->effective_size = ringbuf->size;
 	ringbuf->head = 0;
 	ringbuf->tail = 0;
@@ -2474,7 +2495,7 @@ void intel_lr_context_reset(struct drm_device *dev,
 			WARN(1, "Failed get_pages for context obj\n");
 			continue;
 		}
-		page = i915_gem_object_get_page(ctx_obj, 1);
+		page = i915_gem_object_get_page(ctx_obj, LRC_STATE_PN);
 		reg_state = kmap_atomic(page);
 
 		reg_state[CTX_RING_HEAD+1] = 0;