acpi: factor out common cpu hotplug code for PIIX4/Q35

.. so it could be used for adding CPU hotplug to Q35 machine

Add an additional header with that will be shared between
C and ASL code: include/hw/acpi/cpu_hotplug_defs.h

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>

1 files changed, 64 insertions, 0 deletions

diff --git a/hw/acpi/cpu_hotplug.c b/hw/acpi/cpu_hotplug.c
new file mode 100644
index 0000000000..48928dc0ea
--- /dev/null
+++ b/hw/acpi/cpu_hotplug.c
@@ -0,0 +1,64 @@
+/*
+ * QEMU ACPI hotplug utilities
+ *
+ * Copyright (C) 2013 Red Hat Inc
+ *
+ * Authors:
+ *   Igor Mammedov <imammedo@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+#include "hw/hw.h"
+#include "hw/acpi/cpu_hotplug.h"
+
+static uint64_t cpu_status_read(void *opaque, hwaddr addr, unsigned int size)
+{
+    AcpiCpuHotplug *cpus = opaque;
+    uint64_t val = cpus->sts[addr];
+
+    return val;
+}
+
+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 */
+}
+
+static const MemoryRegionOps AcpiCpuHotplug_ops = {
+    .read = cpu_status_read,
+    .write = cpu_status_write,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 1,
+    },
+};
+
+void AcpiCpuHotplug_add(ACPIGPE *gpe, AcpiCpuHotplug *g, CPUState *cpu)
+{
+    CPUClass *k = CPU_GET_CLASS(cpu);
+    int64_t cpu_id;
+
+    *gpe->sts = *gpe->sts | ACPI_CPU_HOTPLUG_STATUS;
+    cpu_id = k->get_arch_id(CPU(cpu));
+    g->sts[cpu_id / 8] |= (1 << (cpu_id % 8));
+}
+
+void AcpiCpuHotplug_init(MemoryRegion *parent, Object *owner,
+                         AcpiCpuHotplug *gpe_cpu, uint16_t base)
+{
+    CPUState *cpu;
+
+    CPU_FOREACH(cpu) {
+        CPUClass *cc = CPU_GET_CLASS(cpu);
+        int64_t id = cc->get_arch_id(cpu);
+
+        g_assert((id / 8) < ACPI_GPE_PROC_LEN);
+        gpe_cpu->sts[id / 8] |= (1 << (id % 8));
+    }
+    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);
+}