IXGBE_VFTDH
regs_buff[35 + i] = IXGBE_READ_REG(hw, IXGBE_VFTDH(i));
IXGBE_WRITE_REG(hw, IXGBE_VFTDH(reg_idx), 0);
u32 head = IXGBE_READ_REG(hw, IXGBE_VFTDH(ring->reg_idx));
IXGBE_READ_REG(hw, IXGBE_VFTDH(tx_ring->reg_idx)),