vdpa/mlx5: Accept Init -> Ready VQ transition in resume_vq()

Until now resume_vq() was used only for the suspend/resume scenario.
This change also allows calling resume_vq() to bring it from Init to
Ready state (VQ initialization).
Signed-off-by: Dragos Tatulea <dtatulea@nvidia.com>
Reviewed-by: Cosmin Ratiu <cratiu@nvidia.com>
Message-Id: <20240626-stage-vdpa-vq-precreate-v2-16-560c491078df@nvidia.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>
Acked-by: Eugenio Pérez <eperezma@redhat.com>

drivers/vdpa/mlx5/net/mlx5_vnet.c

@@ -1557,11 +1557,31 @@ static void suspend_vqs(struct mlx5_vdpa_net *ndev)
 
 static void resume_vq(struct mlx5_vdpa_net *ndev, struct mlx5_vdpa_virtqueue *mvq)
 {
-	if (!mvq->initialized || !is_resumable(ndev))
+	if (!mvq->initialized)
 		return;
 
-	if (mvq->fw_state != MLX5_VIRTIO_NET_Q_OBJECT_STATE_SUSPEND)
+	switch (mvq->fw_state) {
+	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_INIT:
+		/* Due to a FW quirk we need to modify the VQ fields first then change state.
+		 * This should be fixed soon. After that, a single command can be used.
+		 */
+		if (modify_virtqueue(ndev, mvq, 0))
+			mlx5_vdpa_warn(&ndev->mvdev,
+				"modify vq properties failed for vq %u\n", mvq->index);
+		break;
+	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_SUSPEND:
+		if (!is_resumable(ndev)) {
+			mlx5_vdpa_warn(&ndev->mvdev, "vq %d is not resumable\n", mvq->index);
+			return;
+		}
+		break;
+	case MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY:
 		return;
+	default:
+		mlx5_vdpa_warn(&ndev->mvdev, "resume vq %u called from bad state %d\n",
+			       mvq->index, mvq->fw_state);
+		return;
+	}
 
 	if (modify_virtqueue_state(ndev, mvq, MLX5_VIRTIO_NET_Q_OBJECT_STATE_RDY))
 		mlx5_vdpa_warn(&ndev->mvdev, "modify to resume failed for vq %u\n", mvq->index);