VTCR_EL2_TGRAN_SL0_BASE
FIELD_PREP(VTCR_EL2_SL0, (VTCR_EL2_TGRAN_SL0_BASE - (4 - (levels))))
((sl0) + 4 - VTCR_EL2_TGRAN_SL0_BASE)
s8 start_level = VTCR_EL2_TGRAN_SL0_BASE - sl0;
s8 start_level = VTCR_EL2_TGRAN_SL0_BASE - sl0;