drm/i915/guc: Assert that all GGTT offsets used by the GuC are mappable

Add an assertion to the plain i915_ggtt_offset() to double check that
any offset we hand to the GuC is outside of its unmappable ranges.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20161224193146.4402-1-chris@chris-wilson.co.uk
Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>

drivers/gpu/drm/i915/i915_guc_submission.c

@@ -270,11 +270,11 @@ static void guc_ctx_desc_init(struct intel_guc *guc,
 
 		/* The state page is after PPHWSP */
 		lrc->ring_lcra =
-			i915_ggtt_offset(ce->state) + LRC_STATE_PN * PAGE_SIZE;
+			guc_ggtt_offset(ce->state) + LRC_STATE_PN * PAGE_SIZE;
 		lrc->context_id = (client->ctx_index << GUC_ELC_CTXID_OFFSET) |
 				(guc_engine_id << GUC_ELC_ENGINE_OFFSET);
 
-		lrc->ring_begin = i915_ggtt_offset(ce->ring->vma);
+		lrc->ring_begin = guc_ggtt_offset(ce->ring->vma);
 		lrc->ring_end = lrc->ring_begin + ce->ring->size - 1;
 		lrc->ring_next_free_location = lrc->ring_begin;
 		lrc->ring_current_tail_pointer_value = 0;
@@ -290,7 +290,7 @@ static void guc_ctx_desc_init(struct intel_guc *guc,
 	 * The doorbell, process descriptor, and workqueue are all parts
 	 * of the client object, which the GuC will reference via the GGTT
 	 */
-	gfx_addr = i915_ggtt_offset(client->vma);
+	gfx_addr = guc_ggtt_offset(client->vma);
 	desc.db_trigger_phy = sg_dma_address(client->vma->pages->sgl) +
 				client->doorbell_offset;
 	desc.db_trigger_cpu =
@@ -1226,7 +1226,7 @@ static void guc_log_create(struct intel_guc *guc)
 		(GUC_LOG_ISR_PAGES << GUC_LOG_ISR_SHIFT) |
 		(GUC_LOG_CRASH_PAGES << GUC_LOG_CRASH_SHIFT);
 
-	offset = i915_ggtt_offset(vma) >> PAGE_SHIFT; /* in pages */
+	offset = guc_ggtt_offset(vma) >> PAGE_SHIFT; /* in pages */
 	guc->log.flags = (offset << GUC_LOG_BUF_ADDR_SHIFT) | flags;
 }
 
@@ -1329,7 +1329,7 @@ static void guc_addon_create(struct intel_guc *guc)
 	guc_policies_init(policies);
 
 	ads->scheduler_policies =
-		i915_ggtt_offset(vma) + sizeof(struct guc_ads);
+		guc_ggtt_offset(vma) + sizeof(struct guc_ads);
 
 	/* MMIO reg state */
 	reg_state = (void *)policies + sizeof(struct guc_policies);
@@ -1495,7 +1495,7 @@ int intel_guc_suspend(struct drm_i915_private *dev_priv)
 	/* any value greater than GUC_POWER_D0 */
 	data[1] = GUC_POWER_D1;
 	/* first page is shared data with GuC */
-	data[2] = i915_ggtt_offset(ctx->engine[RCS].state);
+	data[2] = guc_ggtt_offset(ctx->engine[RCS].state);
 
 	return intel_guc_send(guc, data, ARRAY_SIZE(data));
 }
@@ -1522,7 +1522,7 @@ int intel_guc_resume(struct drm_i915_private *dev_priv)
 	data[0] = INTEL_GUC_ACTION_EXIT_S_STATE;
 	data[1] = GUC_POWER_D0;
 	/* first page is shared data with GuC */
-	data[2] = i915_ggtt_offset(ctx->engine[RCS].state);
+	data[2] = guc_ggtt_offset(ctx->engine[RCS].state);
 
 	return intel_guc_send(guc, data, ARRAY_SIZE(data));
 }

drivers/gpu/drm/i915/intel_guc_loader.c

@@ -220,14 +220,14 @@ static void guc_params_init(struct drm_i915_private *dev_priv)
 		params[GUC_CTL_DEBUG] = GUC_LOG_DISABLED;
 
 	if (guc->ads_vma) {
-		u32 ads = i915_ggtt_offset(guc->ads_vma) >> PAGE_SHIFT;
+		u32 ads = guc_ggtt_offset(guc->ads_vma) >> PAGE_SHIFT;
 		params[GUC_CTL_DEBUG] |= ads << GUC_ADS_ADDR_SHIFT;
 		params[GUC_CTL_DEBUG] |= GUC_ADS_ENABLED;
 	}
 
 	/* If GuC submission is enabled, set up additional parameters here */
 	if (i915.enable_guc_submission) {
-		u32 pgs = i915_ggtt_offset(dev_priv->guc.ctx_pool_vma);
+		u32 pgs = guc_ggtt_offset(dev_priv->guc.ctx_pool_vma);
 		u32 ctx_in_16 = GUC_MAX_GPU_CONTEXTS / 16;
 
 		pgs >>= PAGE_SHIFT;
@@ -297,7 +297,7 @@ static int guc_ucode_xfer_dma(struct drm_i915_private *dev_priv,
 	I915_WRITE(DMA_COPY_SIZE, guc_fw->header_size + guc_fw->ucode_size);
 
 	/* Set the source address for the new blob */
-	offset = i915_ggtt_offset(vma) + guc_fw->header_offset;
+	offset = guc_ggtt_offset(vma) + guc_fw->header_offset;
 	I915_WRITE(DMA_ADDR_0_LOW, lower_32_bits(offset));
 	I915_WRITE(DMA_ADDR_0_HIGH, upper_32_bits(offset) & 0xFFFF);
 

drivers/gpu/drm/i915/intel_uc.h

@@ -28,6 +28,8 @@
 #include "i915_guc_reg.h"
 #include "intel_ringbuffer.h"
 
+#include "i915_vma.h"
+
 struct drm_i915_gem_request;
 
 /*
@@ -198,4 +200,11 @@ void i915_guc_register(struct drm_i915_private *dev_priv);
 void i915_guc_unregister(struct drm_i915_private *dev_priv);
 int i915_guc_log_control(struct drm_i915_private *dev_priv, u64 control_val);
 
+static inline u32 guc_ggtt_offset(struct i915_vma *vma)
+{
+	u32 offset = i915_ggtt_offset(vma);
+	GEM_BUG_ON(offset < GUC_WOPCM_TOP);
+	return offset;
+}
+
 #endif