hw/acpi/cpu_hotplug.c

   1 /*
   2  * QEMU ACPI hotplug utilities
   3  *
   4  * Copyright (C) 2013 Red Hat Inc
   5  *
   6  * Authors:
   7  *   Igor Mammedov <imammedo@redhat.com>
   8  *
   9  * This work is licensed under the terms of the GNU GPL, version 2 or later.
  10  * See the COPYING file in the top-level directory.
  11  */
  12 #include "hw/hw.h"
  13 #include "hw/acpi/cpu_hotplug.h"
  14
  15 static uint64_t cpu_status_read(void *opaque, hwaddr addr, unsigned int size)
  16 {
  17     AcpiCpuHotplug *cpus = opaque;
  18     uint64_t val = cpus->sts[addr];
  19
  20     return val;
  21 }
  22
  23 static void cpu_status_write(void *opaque, hwaddr addr, uint64_t data,
  24                              unsigned int size)
  25 {
  26     /* TODO: implement VCPU removal on guest signal that CPU can be removed */
  27 }
  28
  29 static const MemoryRegionOps AcpiCpuHotplug_ops = {
  30     .read = cpu_status_read,
  31     .write = cpu_status_write,
  32     .endianness = DEVICE_LITTLE_ENDIAN,
  33     .valid = {
  34         .min_access_size = 1,
  35         .max_access_size = 1,
  36     },
  37 };
  38
  39 void AcpiCpuHotplug_add(ACPIGPE *gpe, AcpiCpuHotplug *g, CPUState *cpu)
  40 {
  41     CPUClass *k = CPU_GET_CLASS(cpu);
  42     int64_t cpu_id;
  43
  44     *gpe->sts = *gpe->sts | ACPI_CPU_HOTPLUG_STATUS;
  45     cpu_id = k->get_arch_id(CPU(cpu));
  46     g_assert((cpu_id / 8) < ACPI_GPE_PROC_LEN);
  47     g->sts[cpu_id / 8] |= (1 << (cpu_id % 8));
  48 }
  49
  50 void AcpiCpuHotplug_init(MemoryRegion *parent, Object *owner,
  51                          AcpiCpuHotplug *gpe_cpu, uint16_t base)
  52 {
  53     CPUState *cpu;
  54
  55     CPU_FOREACH(cpu) {
  56         CPUClass *cc = CPU_GET_CLASS(cpu);
  57         int64_t id = cc->get_arch_id(cpu);
  58
  59         g_assert((id / 8) < ACPI_GPE_PROC_LEN);
  60         gpe_cpu->sts[id / 8] |= (1 << (id % 8));
  61     }
  62     memory_region_init_io(&gpe_cpu->io, owner, &AcpiCpuHotplug_ops,
  63                           gpe_cpu, "acpi-cpu-hotplug", ACPI_GPE_PROC_LEN);
  64     memory_region_add_subregion(parent, base, &gpe_cpu->io);
  65 }