drm/i915: Sanitize engine context sizes

Pre-calculate engine context size based on engine class and device
generation and store it in the engine instance.

v2:
- Squash and get rid of hw_context_size (Chris)

v3:
- Move after MMIO init for probing on Gen7 and 8 (Chris)
- Retained rounding (Tvrtko)
v4:
- Rebase for deferred legacy context allocation
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Oscar Mateo <oscar.mateo@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: intel-gvt-dev@lists.freedesktop.org
Acked-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>

drivers/gpu/drm/i915/gvt/scheduler.c

@@ -69,8 +69,7 @@ static int populate_shadow_context(struct intel_vgpu_workload *workload)
 	gvt_dbg_sched("ring id %d workload lrca %x", ring_id,
 			workload->ctx_desc.lrca);
 
-	context_page_num = intel_lr_context_size(
-			gvt->dev_priv->engine[ring_id]);
+	context_page_num = gvt->dev_priv->engine[ring_id]->context_size;
 
 	context_page_num = context_page_num >> PAGE_SHIFT;
 
@@ -333,8 +332,7 @@ static void update_guest_context(struct intel_vgpu_workload *workload)
 	gvt_dbg_sched("ring id %d workload lrca %x\n", ring_id,
 			workload->ctx_desc.lrca);
 
-	context_page_num = intel_lr_context_size(
-			gvt->dev_priv->engine[ring_id]);
+	context_page_num = gvt->dev_priv->engine[ring_id]->context_size;
 
 	context_page_num = context_page_num >> PAGE_SHIFT;
 

drivers/gpu/drm/i915/i915_drv.c

@@ -835,10 +835,6 @@ static int i915_driver_init_early(struct drm_i915_private *dev_priv,
 	intel_uc_init_early(dev_priv);
 	i915_memcpy_init_early(dev_priv);
 
-	ret = intel_engines_init_early(dev_priv);
-	if (ret)
-		return ret;
-
 	ret = i915_workqueues_init(dev_priv);
 	if (ret < 0)
 		goto err_engines;
@@ -948,14 +944,21 @@ static int i915_driver_init_mmio(struct drm_i915_private *dev_priv)
 
 	ret = i915_mmio_setup(dev_priv);
 	if (ret < 0)
-		goto put_bridge;
+		goto err_bridge;
 
 	intel_uncore_init(dev_priv);
+
+	ret = intel_engines_init_mmio(dev_priv);
+	if (ret)
+		goto err_uncore;
+
 	i915_gem_init_mmio(dev_priv);
 
 	return 0;
 
-put_bridge:
+err_uncore:
+	intel_uncore_fini(dev_priv);
+err_bridge:
 	pci_dev_put(dev_priv->bridge_dev);
 
 	return ret;

drivers/gpu/drm/i915/i915_drv.h

@@ -2359,7 +2359,6 @@ struct drm_i915_private {
 	 */
 	struct mutex av_mutex;
 
-	uint32_t hw_context_size;
 	struct list_head context_list;
 
 	u32 fdi_rx_config;
@@ -3023,7 +3022,7 @@ extern unsigned long i915_gfx_val(struct drm_i915_private *dev_priv);
 extern void i915_update_gfx_val(struct drm_i915_private *dev_priv);
 int vlv_force_gfx_clock(struct drm_i915_private *dev_priv, bool on);
 
-int intel_engines_init_early(struct drm_i915_private *dev_priv);
+int intel_engines_init_mmio(struct drm_i915_private *dev_priv);
 int intel_engines_init(struct drm_i915_private *dev_priv);
 
 /* intel_hotplug.c */

drivers/gpu/drm/i915/i915_gem_context.c

@@ -92,33 +92,6 @@
 
 #define ALL_L3_SLICES(dev) (1 << NUM_L3_SLICES(dev)) - 1
 
-static int get_context_size(struct drm_i915_private *dev_priv)
-{
-	int ret;
-	u32 reg;
-
-	switch (INTEL_GEN(dev_priv)) {
-	case 6:
-		reg = I915_READ(CXT_SIZE);
-		ret = GEN6_CXT_TOTAL_SIZE(reg) * 64;
-		break;
-	case 7:
-		reg = I915_READ(GEN7_CXT_SIZE);
-		if (IS_HASWELL(dev_priv))
-			ret = HSW_CXT_TOTAL_SIZE;
-		else
-			ret = GEN7_CXT_TOTAL_SIZE(reg) * 64;
-		break;
-	case 8:
-		ret = GEN8_CXT_TOTAL_SIZE;
-		break;
-	default:
-		BUG();
-	}
-
-	return ret;
-}
-
 void i915_gem_context_free(struct kref *ctx_ref)
 {
 	struct i915_gem_context *ctx = container_of(ctx_ref, typeof(*ctx), ref);
@@ -384,21 +357,6 @@ int i915_gem_context_init(struct drm_i915_private *dev_priv)
 	BUILD_BUG_ON(MAX_CONTEXT_HW_ID > INT_MAX);
 	ida_init(&dev_priv->context_hw_ida);
 
-	if (i915.enable_execlists) {
-		/* NB: intentionally left blank. We will allocate our own
-		 * backing objects as we need them, thank you very much */
-		dev_priv->hw_context_size = 0;
-	} else if (HAS_HW_CONTEXTS(dev_priv)) {
-		dev_priv->hw_context_size =
-			round_up(get_context_size(dev_priv),
-				 I915_GTT_PAGE_SIZE);
-		if (dev_priv->hw_context_size > (1<<20)) {
-			DRM_DEBUG_DRIVER("Disabling HW Contexts; invalid size %d\n",
-					 dev_priv->hw_context_size);
-			dev_priv->hw_context_size = 0;
-		}
-	}
-
 	ctx = i915_gem_create_context(dev_priv, NULL);
 	if (IS_ERR(ctx)) {
 		DRM_ERROR("Failed to create default global context (error %ld)\n",
@@ -418,8 +376,8 @@ int i915_gem_context_init(struct drm_i915_private *dev_priv)
 	GEM_BUG_ON(!i915_gem_context_is_kernel(ctx));
 
 	DRM_DEBUG_DRIVER("%s context support initialized\n",
-			i915.enable_execlists ? "LR" :
-			dev_priv->hw_context_size ? "HW" : "fake");
+			 dev_priv->engine[RCS]->context_size ? "logical" :
+			 "fake");
 	return 0;
 }
 
@@ -882,11 +840,6 @@ int i915_gem_switch_to_kernel_context(struct drm_i915_private *dev_priv)
 	return 0;
 }
 
-static bool contexts_enabled(struct drm_device *dev)
-{
-	return i915.enable_execlists || to_i915(dev)->hw_context_size;
-}
-
 static bool client_is_banned(struct drm_i915_file_private *file_priv)
 {
 	return file_priv->context_bans > I915_MAX_CLIENT_CONTEXT_BANS;
@@ -895,12 +848,13 @@ static bool client_is_banned(struct drm_i915_file_private *file_priv)
 int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
 				  struct drm_file *file)
 {
+	struct drm_i915_private *dev_priv = to_i915(dev);
 	struct drm_i915_gem_context_create *args = data;
 	struct drm_i915_file_private *file_priv = file->driver_priv;
 	struct i915_gem_context *ctx;
 	int ret;
 
-	if (!contexts_enabled(dev))
+	if (!dev_priv->engine[RCS]->context_size)
 		return -ENODEV;
 
 	if (args->pad != 0)
@@ -918,7 +872,7 @@ int i915_gem_context_create_ioctl(struct drm_device *dev, void *data,
 	if (ret)
 		return ret;
 
-	ctx = i915_gem_create_context(to_i915(dev), file_priv);
+	ctx = i915_gem_create_context(dev_priv, file_priv);
 	mutex_unlock(&dev->struct_mutex);
 	if (IS_ERR(ctx))
 		return PTR_ERR(ctx);

drivers/gpu/drm/i915/i915_guc_submission.c

@@ -1051,8 +1051,7 @@ static int guc_ads_create(struct intel_guc *guc)
 		dev_priv->engine[RCS]->status_page.ggtt_offset;
 
 	for_each_engine(engine, dev_priv, id)
-		blob->ads.eng_state_size[engine->guc_id] =
-			intel_lr_context_size(engine);
+		blob->ads.eng_state_size[engine->guc_id] = engine->context_size;
 
 	base = guc_ggtt_offset(vma);
 	blob->ads.scheduler_policies = base + ptr_offset(blob, policies);

drivers/gpu/drm/i915/i915_reg.h

@@ -3370,16 +3370,6 @@ enum skl_disp_power_wells {
 #define GEN7_CXT_VFSTATE_SIZE(ctx_reg)	(((ctx_reg) >> 0) & 0x3f)
 #define GEN7_CXT_TOTAL_SIZE(ctx_reg)	(GEN7_CXT_EXTENDED_SIZE(ctx_reg) + \
 					 GEN7_CXT_VFSTATE_SIZE(ctx_reg))
-/* Haswell does have the CXT_SIZE register however it does not appear to be
- * valid. Now, docs explain in dwords what is in the context object. The full
- * size is 70720 bytes, however, the power context and execlist context will
- * never be saved (power context is stored elsewhere, and execlists don't work
- * on HSW) - so the final size, including the extra state required for the
- * Resource Streamer, is 66944 bytes, which rounds to 17 pages.
- */
-#define HSW_CXT_TOTAL_SIZE		(17 * PAGE_SIZE)
-/* Same as Haswell, but 72064 bytes now. */
-#define GEN8_CXT_TOTAL_SIZE		(18 * PAGE_SIZE)
 
 enum {
 	INTEL_ADVANCED_CONTEXT = 0,

drivers/gpu/drm/i915/intel_engine_cs.c

@@ -26,6 +26,22 @@
 #include "intel_ringbuffer.h"
 #include "intel_lrc.h"
 
+/* Haswell does have the CXT_SIZE register however it does not appear to be
+ * valid. Now, docs explain in dwords what is in the context object. The full
+ * size is 70720 bytes, however, the power context and execlist context will
+ * never be saved (power context is stored elsewhere, and execlists don't work
+ * on HSW) - so the final size, including the extra state required for the
+ * Resource Streamer, is 66944 bytes, which rounds to 17 pages.
+ */
+#define HSW_CXT_TOTAL_SIZE		(17 * PAGE_SIZE)
+/* Same as Haswell, but 72064 bytes now. */
+#define GEN8_CXT_TOTAL_SIZE		(18 * PAGE_SIZE)
+
+#define GEN8_LR_CONTEXT_RENDER_SIZE	(20 * PAGE_SIZE)
+#define GEN9_LR_CONTEXT_RENDER_SIZE	(22 * PAGE_SIZE)
+
+#define GEN8_LR_CONTEXT_OTHER_SIZE	( 2 * PAGE_SIZE)
+
 struct engine_class_info {
 	const char *name;
 	int (*init_legacy)(struct intel_engine_cs *engine);
@@ -107,6 +123,69 @@ static const struct engine_info intel_engines[] = {
 	},
 };
 
+/**
+ * ___intel_engine_context_size() - return the size of the context for an engine
+ * @dev_priv: i915 device private
+ * @class: engine class
+ *
+ * Each engine class may require a different amount of space for a context
+ * image.
+ *
+ * Return: size (in bytes) of an engine class specific context image
+ *
+ * Note: this size includes the HWSP, which is part of the context image
+ * in LRC mode, but does not include the "shared data page" used with
+ * GuC submission. The caller should account for this if using the GuC.
+ */
+static u32
+__intel_engine_context_size(struct drm_i915_private *dev_priv, u8 class)
+{
+	u32 cxt_size;
+
+	BUILD_BUG_ON(I915_GTT_PAGE_SIZE != PAGE_SIZE);
+
+	switch (class) {
+	case RENDER_CLASS:
+		switch (INTEL_GEN(dev_priv)) {
+		default:
+			MISSING_CASE(INTEL_GEN(dev_priv));
+		case 9:
+			return GEN9_LR_CONTEXT_RENDER_SIZE;
+		case 8:
+			return i915.enable_execlists ?
+			       GEN8_LR_CONTEXT_RENDER_SIZE :
+			       GEN8_CXT_TOTAL_SIZE;
+		case 7:
+			if (IS_HASWELL(dev_priv))
+				return HSW_CXT_TOTAL_SIZE;
+
+			cxt_size = I915_READ(GEN7_CXT_SIZE);
+			return round_up(GEN7_CXT_TOTAL_SIZE(cxt_size) * 64,
+					PAGE_SIZE);
+		case 6:
+			cxt_size = I915_READ(CXT_SIZE);
+			return round_up(GEN6_CXT_TOTAL_SIZE(cxt_size) * 64,
+					PAGE_SIZE);
+		case 5:
+		case 4:
+		case 3:
+		case 2:
+		/* For the special day when i810 gets merged. */
+		case 1:
+			return 0;
+		}
+		break;
+	default:
+		MISSING_CASE(class);
+	case VIDEO_DECODE_CLASS:
+	case VIDEO_ENHANCEMENT_CLASS:
+	case COPY_ENGINE_CLASS:
+		if (INTEL_GEN(dev_priv) < 8)
+			return 0;
+		return GEN8_LR_CONTEXT_OTHER_SIZE;
+	}
+}
+
 static int
 intel_engine_setup(struct drm_i915_private *dev_priv,
 		   enum intel_engine_id id)
@@ -135,6 +214,11 @@ intel_engine_setup(struct drm_i915_private *dev_priv,
 	engine->class = info->class;
 	engine->instance = info->instance;
 
+	engine->context_size = __intel_engine_context_size(dev_priv,
+							   engine->class);
+	if (WARN_ON(engine->context_size > BIT(20)))
+		engine->context_size = 0;
+
 	/* Nothing to do here, execute in order of dependencies */
 	engine->schedule = NULL;
 
@@ -145,12 +229,12 @@ intel_engine_setup(struct drm_i915_private *dev_priv,
 }
 
 /**
- * intel_engines_init_early() - allocate the Engine Command Streamers
+ * intel_engines_init_mmio() - allocate and prepare the Engine Command Streamers
  * @dev_priv: i915 device private
  *
  * Return: non-zero if the initialization failed.
  */
-int intel_engines_init_early(struct drm_i915_private *dev_priv)
+int intel_engines_init_mmio(struct drm_i915_private *dev_priv)
 {
 	struct intel_device_info *device_info = mkwrite_device_info(dev_priv);
 	const unsigned int ring_mask = INTEL_INFO(dev_priv)->ring_mask;
@@ -200,7 +284,7 @@ int intel_engines_init_early(struct drm_i915_private *dev_priv)
 }
 
 /**
- * intel_engines_init() - allocate, populate and init the Engine Command Streamers
+ * intel_engines_init() - init the Engine Command Streamers
  * @dev_priv: i915 device private
  *
  * Return: non-zero if the initialization failed.

drivers/gpu/drm/i915/intel_lrc.c

@@ -138,10 +138,6 @@
 #include "i915_drv.h"
 #include "intel_mocs.h"
 
-#define GEN9_LR_CONTEXT_RENDER_SIZE (22 * PAGE_SIZE)
-#define GEN8_LR_CONTEXT_RENDER_SIZE (20 * PAGE_SIZE)
-#define GEN8_LR_CONTEXT_OTHER_SIZE (2 * PAGE_SIZE)
-
 #define RING_EXECLIST_QFULL		(1 << 0x2)
 #define RING_EXECLIST1_VALID		(1 << 0x3)
 #define RING_EXECLIST0_VALID		(1 << 0x4)
@@ -1918,53 +1914,6 @@ populate_lr_context(struct i915_gem_context *ctx,
 	return 0;
 }
 
-/**
- * intel_lr_context_size() - return the size of the context for an engine
- * @engine: which engine to find the context size for
- *
- * Each engine may require a different amount of space for a context image,
- * so when allocating (or copying) an image, this function can be used to
- * find the right size for the specific engine.
- *
- * Return: size (in bytes) of an engine-specific context image
- *
- * Note: this size includes the HWSP, which is part of the context image
- * in LRC mode, but does not include the "shared data page" used with
- * GuC submission. The caller should account for this if using the GuC.
- */
-uint32_t intel_lr_context_size(struct intel_engine_cs *engine)
-{
-	struct drm_i915_private *dev_priv = engine->i915;
-	int ret;
-
-	WARN_ON(INTEL_GEN(dev_priv) < 8);
-
-	switch (engine->class) {
-	case RENDER_CLASS:
-		switch (INTEL_GEN(dev_priv)) {
-		default:
-			MISSING_CASE(INTEL_GEN(dev_priv));
-		case 9:
-			ret = GEN9_LR_CONTEXT_RENDER_SIZE;
-			break;
-		case 8:
-			ret = GEN8_LR_CONTEXT_RENDER_SIZE;
-			break;
-		}
-		break;
-
-	default:
-		MISSING_CASE(engine->class);
-	case VIDEO_DECODE_CLASS:
-	case VIDEO_ENHANCEMENT_CLASS:
-	case COPY_ENGINE_CLASS:
-		ret = GEN8_LR_CONTEXT_OTHER_SIZE;
-		break;
-	}
-
-	return ret;
-}
-
 static int execlists_context_deferred_alloc(struct i915_gem_context *ctx,
 					    struct intel_engine_cs *engine)
 {
@@ -1977,8 +1926,7 @@ static int execlists_context_deferred_alloc(struct i915_gem_context *ctx,
 
 	WARN_ON(ce->state);
 
-	context_size = round_up(intel_lr_context_size(engine),
-				I915_GTT_PAGE_SIZE);
+	context_size = round_up(engine->context_size, I915_GTT_PAGE_SIZE);
 
 	/* One extra page as the sharing data between driver and GuC */
 	context_size += PAGE_SIZE * LRC_PPHWSP_PN;

drivers/gpu/drm/i915/intel_lrc.h

@@ -78,8 +78,6 @@ int logical_xcs_ring_init(struct intel_engine_cs *engine);
 struct drm_i915_private;
 struct i915_gem_context;
 
-uint32_t intel_lr_context_size(struct intel_engine_cs *engine);
-
 void intel_lr_context_resume(struct drm_i915_private *dev_priv);
 uint64_t intel_lr_context_descriptor(struct i915_gem_context *ctx,
 				     struct intel_engine_cs *engine);

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -1444,7 +1444,7 @@ alloc_context_vma(struct intel_engine_cs *engine)
 	struct drm_i915_gem_object *obj;
 	struct i915_vma *vma;
 
-	obj = i915_gem_object_create(i915, i915->hw_context_size);
+	obj = i915_gem_object_create(i915, engine->context_size);
 	if (IS_ERR(obj))
 		return ERR_CAST(obj);
 
@@ -1487,7 +1487,7 @@ static int intel_ring_context_pin(struct intel_engine_cs *engine,
 		return 0;
 	GEM_BUG_ON(!ce->pin_count); /* no overflow please! */
 
-	if (engine->id == RCS && !ce->state && engine->i915->hw_context_size) {
+	if (!ce->state && engine->context_size) {
 		struct i915_vma *vma;
 
 		vma = alloc_context_vma(engine);

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -196,13 +196,14 @@ struct intel_engine_cs {
 	enum intel_engine_id id;
 	unsigned int uabi_id;
 	unsigned int hw_id;
+	unsigned int guc_id;
 
 	u8 class;
 	u8 instance;
-
-	unsigned int guc_id;
+	u32 context_size;
 	u32 mmio_base;
 	unsigned int irq_shift;
+
 	struct intel_ring *buffer;
 	struct intel_timeline *timeline;