The 32bit software are mostly compatible with Debian 4.0 (libc 2.3.6) onwards, and 64bit software are compatible with Debian 7.7 (libc 2.13) onwards.
The software with tag mipsel or mips64el here only support Linux running on MIPS machine in little-endian mode; software with tag mips or mips64 are for Linux running on MIPS machine in big-endian mode.