Comment 6 for bug 1853083

and it got:
[root@192 emu]# ./aix51
VNC server running on ::1:5900
qemu-system-ppc64: warning: TCG doesn't support requested feature, cap-cfpc=workaround
qemu-system-ppc64: warning: TCG doesn't support requested feature, cap-sbbc=workaround
qemu-system-ppc64: warning: TCG doesn't support requested feature, cap-ibs=workaround

SLOF **********************************************************************
QEMU Starting
 Build Date = Jul 3 2019 12:26:14
 FW Version = git-ba1ab360eebe6338
 Press "s" to enter Open Firmware.

Populating /vdevice methods
Populating /vdevice/vty@71000000
Populating /vdevice/nvram@71000001
Populating /vdevice/l-lan@71000002
Populating /vdevice/v-scsi@71000003
       SCSI: Looking for devices
          8000000000000000 DISK : "QEMU QEMU HARDDISK 2.5+"
          8200000000000000 CD-ROM : "QEMU QEMU CD-ROM 2.5+"
Populating /pci@800000020000000
                     00 0000 (D) : 1234 1111 qemu vga
                     00 0800 (D) : 1033 0194 serial bus [ usb-xhci ]
Installing QEMU fb

Scanning USB
  XHCI: Initializing
    USB Keyboard
    USB mouse
No console specified using screen & keyboard

  Welcome to Open Firmware

  Copyright (c) 2004, 2017 IBM Corporation All rights reserved.
  This program and the accompanying materials are made available
  under the terms of the BSD License available at
  http://www.opensource.org/licenses/bsd-license.php

Trying to load: -s verbose from: /vdevice/v-scsi@71000003/disk@8200000000000000: ...

and just hung there, took lots of CPU time, never proceed further.