drm/i915/gvt: add hotplug emulation

Add function to emulate hotplug interrupt for SKL/KBL platforms
Signed-off-by: Hang Yuan <hang.yuan@linux.intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

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

@@ -445,6 +445,36 @@ void intel_gvt_emulate_vblank(struct intel_gvt *gvt)
 	mutex_unlock(&gvt->lock);
 }
 
+/**
+ * intel_vgpu_emulate_hotplug - trigger hotplug event for vGPU
+ * @vgpu: a vGPU
+ * @conncted: link state
+ *
+ * This function is used to trigger hotplug interrupt for vGPU
+ *
+ */
+void intel_vgpu_emulate_hotplug(struct intel_vgpu *vgpu, bool connected)
+{
+	struct drm_i915_private *dev_priv = vgpu->gvt->dev_priv;
+
+	/* TODO: add more platforms support */
+	if (IS_SKYLAKE(dev_priv) || IS_KABYLAKE(dev_priv)) {
+		if (connected) {
+			vgpu_vreg_t(vgpu, SFUSE_STRAP) |=
+				SFUSE_STRAP_DDID_DETECTED;
+			vgpu_vreg_t(vgpu, SDEISR) |= SDE_PORTD_HOTPLUG_CPT;
+		} else {
+			vgpu_vreg_t(vgpu, SFUSE_STRAP) &=
+				~SFUSE_STRAP_DDID_DETECTED;
+			vgpu_vreg_t(vgpu, SDEISR) &= ~SDE_PORTD_HOTPLUG_CPT;
+		}
+		vgpu_vreg_t(vgpu, SDEIIR) |= SDE_PORTD_HOTPLUG_CPT;
+		vgpu_vreg_t(vgpu, PCH_PORT_HOTPLUG) |=
+				PORTD_HOTPLUG_STATUS_MASK;
+		intel_vgpu_trigger_virtual_event(vgpu, DP_D_HOTPLUG);
+	}
+}
+
 /**
  * intel_vgpu_clean_display - clean vGPU virtual display emulation
  * @vgpu: a vGPU

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

@@ -185,6 +185,7 @@ static const struct intel_gvt_ops intel_gvt_ops = {
 	.vgpu_query_plane = intel_vgpu_query_plane,
 	.vgpu_get_dmabuf = intel_vgpu_get_dmabuf,
 	.write_protect_handler = intel_vgpu_page_track_handler,
+	.emulate_hotplug = intel_vgpu_emulate_hotplug,
 };
 
 static void init_device_info(struct intel_gvt *gvt)

drivers/gpu/drm/i915/gvt/gvt.h

@@ -536,6 +536,8 @@ int intel_vgpu_emulate_cfg_read(struct intel_vgpu *vgpu, unsigned int offset,
 int intel_vgpu_emulate_cfg_write(struct intel_vgpu *vgpu, unsigned int offset,
 		void *p_data, unsigned int bytes);
 
+void intel_vgpu_emulate_hotplug(struct intel_vgpu *vgpu, bool connected);
+
 static inline u64 intel_vgpu_get_bar_gpa(struct intel_vgpu *vgpu, int bar)
 {
 	/* We are 64bit bar. */
@@ -577,6 +579,7 @@ struct intel_gvt_ops {
 	int (*vgpu_get_dmabuf)(struct intel_vgpu *vgpu, unsigned int);
 	int (*write_protect_handler)(struct intel_vgpu *, u64, void *,
 				     unsigned int);
+	void (*emulate_hotplug)(struct intel_vgpu *vgpu, bool connected);
 };