drm/i915/gvt: rewrite gt reset handler using new function intel_gvt_reset_vgpu_locked

GT reset and FLR share some operations and they are both implemented in
our new function intel_gvt_reset_vgpu_locked(). This patch rewrite the
gt reset handler using this new function.

Besides, this new implementation fixed the old issue in GT reset. The
old implementation reset GGTT entries which is illegal. We only clear
GGTT entries at PCI level reset.
Signed-off-by: Changbin Du <changbin.du@intel.com>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>

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

@@ -231,77 +231,45 @@ static int mul_force_wake_write(struct intel_vgpu *vgpu,
 	return 0;
 }
 
-static int handle_device_reset(struct intel_vgpu *vgpu, unsigned int offset,
-		void *p_data, unsigned int bytes, unsigned long bitmap)
-{
-	struct intel_gvt_workload_scheduler *scheduler =
-		&vgpu->gvt->scheduler;
-
-	vgpu->resetting = true;
-
-	intel_vgpu_stop_schedule(vgpu);
-	/*
-	 * The current_vgpu will set to NULL after stopping the
-	 * scheduler when the reset is triggered by current vgpu.
-	 */
-	if (scheduler->current_vgpu == NULL) {
-		mutex_unlock(&vgpu->gvt->lock);
-		intel_gvt_wait_vgpu_idle(vgpu);
-		mutex_lock(&vgpu->gvt->lock);
-	}
-
-	intel_vgpu_reset_execlist(vgpu, bitmap);
-
-	/* full GPU reset */
-	if (bitmap == 0xff) {
-		mutex_unlock(&vgpu->gvt->lock);
-		intel_vgpu_clean_gtt(vgpu);
-		mutex_lock(&vgpu->gvt->lock);
-		intel_vgpu_init_mmio(vgpu);
-		populate_pvinfo_page(vgpu);
-		intel_vgpu_init_gtt(vgpu);
-	}
-
-	vgpu->resetting = false;
-
-	return 0;
-}
-
 static int gdrst_mmio_write(struct intel_vgpu *vgpu, unsigned int offset,
-		void *p_data, unsigned int bytes)
+			    void *p_data, unsigned int bytes)
 {
+	unsigned int engine_mask = 0;
 	u32 data;
-	u64 bitmap = 0;
 
 	write_vreg(vgpu, offset, p_data, bytes);
 	data = vgpu_vreg(vgpu, offset);
 
 	if (data & GEN6_GRDOM_FULL) {
 		gvt_dbg_mmio("vgpu%d: request full GPU reset\n", vgpu->id);
-		bitmap = 0xff;
-	}
-	if (data & GEN6_GRDOM_RENDER) {
-		gvt_dbg_mmio("vgpu%d: request RCS reset\n", vgpu->id);
-		bitmap |= (1 << RCS);
-	}
-	if (data & GEN6_GRDOM_MEDIA) {
-		gvt_dbg_mmio("vgpu%d: request VCS reset\n", vgpu->id);
-		bitmap |= (1 << VCS);
-	}
-	if (data & GEN6_GRDOM_BLT) {
-		gvt_dbg_mmio("vgpu%d: request BCS Reset\n", vgpu->id);
-		bitmap |= (1 << BCS);
-	}
-	if (data & GEN6_GRDOM_VECS) {
-		gvt_dbg_mmio("vgpu%d: request VECS Reset\n", vgpu->id);
-		bitmap |= (1 << VECS);
-	}
-	if (data & GEN8_GRDOM_MEDIA2) {
-		gvt_dbg_mmio("vgpu%d: request VCS2 Reset\n", vgpu->id);
-		if (HAS_BSD2(vgpu->gvt->dev_priv))
-			bitmap |= (1 << VCS2);
+		engine_mask = ALL_ENGINES;
+	} else {
+		if (data & GEN6_GRDOM_RENDER) {
+			gvt_dbg_mmio("vgpu%d: request RCS reset\n", vgpu->id);
+			engine_mask |= (1 << RCS);
+		}
+		if (data & GEN6_GRDOM_MEDIA) {
+			gvt_dbg_mmio("vgpu%d: request VCS reset\n", vgpu->id);
+			engine_mask |= (1 << VCS);
+		}
+		if (data & GEN6_GRDOM_BLT) {
+			gvt_dbg_mmio("vgpu%d: request BCS Reset\n", vgpu->id);
+			engine_mask |= (1 << BCS);
+		}
+		if (data & GEN6_GRDOM_VECS) {
+			gvt_dbg_mmio("vgpu%d: request VECS Reset\n", vgpu->id);
+			engine_mask |= (1 << VECS);
+		}
+		if (data & GEN8_GRDOM_MEDIA2) {
+			gvt_dbg_mmio("vgpu%d: request VCS2 Reset\n", vgpu->id);
+			if (HAS_BSD2(vgpu->gvt->dev_priv))
+				engine_mask |= (1 << VCS2);
+		}
 	}
-	return handle_device_reset(vgpu, offset, p_data, bytes, bitmap);
+
+	intel_gvt_reset_vgpu_locked(vgpu, false, engine_mask);
+
+	return 0;
 }
 
 static int gmbus_mmio_read(struct intel_vgpu *vgpu, unsigned int offset,