QEMU (with its pseries machine type) doesn't actually run the PowerVM hypervisor, but rather it directly implements a very similar hypervisor-guest interface (based on the Power Architecture Platform Reference and Open Firmware) such that they are treated as the same hardware platform in Linux's eyes.

QEMU is also capable of emulating a variety of other PowerPC machine types, including PowerNV/OpenPOWER bare-metal systems, various Power Macs, RS/6000s etc.