1 files changed, 43 insertions, 8 deletions

diff --git a/drivers/gpu/drm/i915/gvt/render.c b/drivers/gpu/drm/i915/gvt/render.c
index c6e7972ac21d..504e57c3bc23 100644
--- a/drivers/gpu/drm/i915/gvt/render.c
+++ b/drivers/gpu/drm/i915/gvt/render.c
@@ -35,6 +35,7 @@
 
 #include "i915_drv.h"
 #include "gvt.h"
+#include "trace.h"
 
 struct render_mmio {
 	int ring_id;
@@ -260,7 +261,8 @@ static void restore_mocs(struct intel_vgpu *vgpu, int ring_id)
 
 #define CTX_CONTEXT_CONTROL_VAL	0x03
 
-void intel_gvt_load_render_mmio(struct intel_vgpu *vgpu, int ring_id)
+/* Switch ring mmio values (context) from host to a vgpu. */
+static void switch_mmio_to_vgpu(struct intel_vgpu *vgpu, int ring_id)
 {
 	struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
 	struct render_mmio *mmio;
@@ -305,14 +307,15 @@ void intel_gvt_load_render_mmio(struct intel_vgpu *vgpu, int ring_id)
 		I915_WRITE(mmio->reg, v);
 		POSTING_READ(mmio->reg);
 
-		gvt_dbg_render("load reg %x old %x new %x\n",
-				i915_mmio_reg_offset(mmio->reg),
-				mmio->value, v);
+		trace_render_mmio(vgpu->id, "load",
+				  i915_mmio_reg_offset(mmio->reg),
+				  mmio->value, v);
 	}
 	handle_tlb_pending_event(vgpu, ring_id);
 }
 
-void intel_gvt_restore_render_mmio(struct intel_vgpu *vgpu, int ring_id)
+/* Switch ring mmio values (context) from vgpu to host. */
+static void switch_mmio_to_host(struct intel_vgpu *vgpu, int ring_id)
 {
 	struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
 	struct render_mmio *mmio;
@@ -340,11 +343,43 @@ void intel_gvt_restore_render_mmio(struct intel_vgpu *vgpu, int ring_id)
 		} else
 			v = mmio->value;
 
+		if (mmio->in_context)
+			continue;
+
 		I915_WRITE(mmio->reg, v);
 		POSTING_READ(mmio->reg);
 
-		gvt_dbg_render("restore reg %x old %x new %x\n",
-				i915_mmio_reg_offset(mmio->reg),
-				mmio->value, v);
+		trace_render_mmio(vgpu->id, "restore",
+				  i915_mmio_reg_offset(mmio->reg),
+				  mmio->value, v);
 	}
 }
+
+/**
+ * intel_gvt_switch_render_mmio - switch mmio context of specific engine
+ * @pre: the last vGPU that own the engine
+ * @next: the vGPU to switch to
+ * @ring_id: specify the engine
+ *
+ * If pre is null indicates that host own the engine. If next is null
+ * indicates that we are switching to host workload.
+ */
+void intel_gvt_switch_mmio(struct intel_vgpu *pre,
+			   struct intel_vgpu *next, int ring_id)
+{
+	if (WARN_ON(!pre && !next))
+		return;
+
+	gvt_dbg_render("switch ring %d from %s to %s\n", ring_id,
+		       pre ? "vGPU" : "host", next ? "vGPU" : "HOST");
+
+	/**
+	 * TODO: Optimize for vGPU to vGPU switch by merging
+	 * switch_mmio_to_host() and switch_mmio_to_vgpu().
+	 */
+	if (pre)
+		switch_mmio_to_host(pre, ring_id);
+
+	if (next)
+		switch_mmio_to_vgpu(next, ring_id);
+}