CONFIG_LOONGSON3_ENHANCEMENT is not available for thedefaultarchitecture x86.
Result is shown for architecture mips

New Loongson 3 CPU Enhancements

configname: CONFIG_LOONGSON3_ENHANCEMENT

CPU type
└─>New Loongson 3 CPU Enhancements
In linux kernel since version 3.10 (release Date: 2013-06-30)  
New Loongson 3 CPU (since Loongson-3A R2, as opposed to Loongson-3A
R1, Loongson-3B R1 and Loongson-3B R2) has many enhancements, such as
FTLB, L1-VCache, EI/DI/Wait/Prefetch instruction, DSP/DSPv2 ASE, User
Local register, Read-Inhibit/Execute-Inhibit, SFB (Store Fill Buffer),
Fast TLB refill support, etc.

This option enable those enhancements which are not probed at run
time. If you want a generic kernel to run on all Loongson 3 machines,
please say 'N' here. If you want a high-performance kernel to run on
new Loongson 3 machines only, please say 'Y' here.