Loongson 3A is MIPS64R2-compatible, so this means that it should based on ISA_MIPS64R2 (not ISA_MIPS64) ? References: http://www.loongson.cn/uploadfile/201204/Loongson3A_processor_user_manual_P2_GS464processor_core_V1.3.pdf (Page 16)
Created attachment 7103 [details] Patch
Patch applied.