diff options
Diffstat (limited to 'hw/acpi/cpu_hotplug.c')
| -rw-r--r-- | hw/acpi/cpu_hotplug.c | 21 |
1 files changed, 20 insertions, 1 deletions
diff --git a/hw/acpi/cpu_hotplug.c b/hw/acpi/cpu_hotplug.c index fe75bd9ac9..e19d902063 100644 --- a/hw/acpi/cpu_hotplug.c +++ b/hw/acpi/cpu_hotplug.c @@ -34,7 +34,15 @@ static uint64_t cpu_status_read(void *opaque, hwaddr addr, unsigned int size) static void cpu_status_write(void *opaque, hwaddr addr, uint64_t data, unsigned int size) { - /* TODO: implement VCPU removal on guest signal that CPU can be removed */ + /* firmware never used to write in CPU present bitmap so use + this fact as means to switch QEMU into modern CPU hotplug + mode by writing 0 at the beginning of legacy CPU bitmap + */ + if (addr == 0 && data == 0) { + AcpiCpuHotplug *cpus = opaque; + object_property_set_bool(cpus->device, false, "cpu-hotplug-legacy", + &error_abort); + } } static const MemoryRegionOps AcpiCpuHotplug_ops = { @@ -83,6 +91,17 @@ void legacy_acpi_cpu_hotplug_init(MemoryRegion *parent, Object *owner, memory_region_init_io(&gpe_cpu->io, owner, &AcpiCpuHotplug_ops, gpe_cpu, "acpi-cpu-hotplug", ACPI_GPE_PROC_LEN); memory_region_add_subregion(parent, base, &gpe_cpu->io); + gpe_cpu->device = owner; +} + +void acpi_switch_to_modern_cphp(AcpiCpuHotplug *gpe_cpu, + CPUHotplugState *cpuhp_state, + uint16_t io_port) +{ + MemoryRegion *parent = pci_address_space_io(PCI_DEVICE(gpe_cpu->device)); + + memory_region_del_subregion(parent, &gpe_cpu->io); + cpu_hotplug_hw_init(parent, gpe_cpu->device, cpuhp_state, io_port); } void build_legacy_cpu_hotplug_aml(Aml *ctx, MachineState *machine, |