The right of redemption does not extend to any sale under and by virtue of a power contained in any deed of trust, mortgage, or other instrument, whereby the right is waived or surrendered by such mortgage or conveyance.
Waiver of right in mortgage or trust deed
Tenn. Code Ann. § 66-8-103, under Redemption of Real Estate Sold for Debt.
Tenn. Code Ann. § 66-8-103