Tenn. Code Ann. § 65-10-202

To secure this direct lien, such subcontractor, laborer, materialman, or other person rendering the labor or service, shall, within ninety (90) days after such work and labor is done or completed, or such materials are furnished, or such services are rendered, notify, in writing, any such railroad company, or the owners of such railroad, should it or they reside in the state, or its or their agents or attorneys, should it or they be beyond the limit of the state, that the lien is claimed, specifying in the face of the notice the character of the work and labor done or services rendered, or materials furnished, and the value of such labor, services or materials.