diff options
| author | Igor Mammedov <imammedo@redhat.com> | 2016-06-15 11:25:23 +0200 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2016-06-24 05:21:38 +0300 |
| commit | 679dd1a957df418453efdd3ed2914dba5cd73773 (patch) | |
| tree | 857364d455ba3943702e90d93e568b5da488273d /hw/acpi/cpu_hotplug.c | |
| parent | 76623d00ae578335f6c9f31cd13fc5bf1931dbc3 (diff) | |
| download | qemu-679dd1a957df418453efdd3ed2914dba5cd73773.tar.gz | |
pc: use new CPU hotplug interface since 2.7 machine type
For compatibility reasons PC/Q35 will start with legacy
CPU hotplug interface by default but with new CPU hotplug
AML code since 2.7 machine type. That way legacy firmware
that doesn't use QEMU generated ACPI tables will be
able to continue using legacy CPU hotplug interface.
While new machine type, with firmware supporting QEMU
provided ACPI tables, will generate new CPU hotplug AML,
which will switch to new CPU hotplug interface when
guest OS executes its _INI method on ACPI tables
loading.
Signed-off-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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, |