This feature is not documented in the PIIX4 datasheet. It appears to be only used on the i440fx PC machine. Add a property to the PIIX4_PM device to restrict its use. This fixes MIPS guest crashing QEMU when accessing ioport 0xaf00.
Philippe Mathieu-Daudé (2): hw/acpi/piix4: Add 'system-hotplug-support' property hw/acpi/piix4: Restrict system-hotplug-support to x86 i440fx PC machine include/hw/southbridge/piix.h | 3 ++- hw/acpi/piix4.c | 13 ++++++++++--- hw/i386/pc_piix.c | 1 + hw/isa/piix4.c | 2 +- 4 files changed, 14 insertions(+), 5 deletions(-) -- 2.21.1