MIPS support in naken_asm includes standard MIPS (including 64 bit instructions), MIPS32, PIC32, and Playstation 2's R5900.
This is the generic MIPS option. It defaults to big endian, although it can be switched to little endian with the .little_endian directive.
This is pretty much the same as the .mips option, except it defaults to little endian. Again, it can be switched to big endian with the .big_endian directive.
This is pretty much the same as the .mips32 option.
This is the same as .mips except it defaults to little endian and adds Playstation 2 specific instructions including SIMD vector instructions.
This is for the Nintendo 64 Reality Signal Processor (RSP). This adds all the vector instructions for the processor inside the graphics chip in the Nintendo 64. The syntax naken_asm uses is the same syntax used in the official RSP programmer's guide and defaults to big endian.