Xiaomi and Samsung have reputedly teamed up to produce a custom SoC. Apparently, the chipset will feature the upcoming ARM Cortex-X2, along with ARM Mali GPU cores. The pair are believed to be in advanced negotiations.
https://www.notebookcheck.net/Xiaomi-custom-silicon-purported-to-be-in-the-pipeline-with-sporting-an-ARM-Cortex-X2-and-ARM-Mali-GPU-cores.535906.0.html