[Qemu-devel] [RFC 18/42] acpi: hardware side of CPU hotplug

[Igor Mammedov <imammedo@redhat.com>]

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
 hw/acpi/Makefile.objs |   1 +
 hw/acpi/cpu.c         | 218 ++++++++++++++++++++++++++++++++++++++++++++++++++
 include/hw/acpi/cpu.h |  53 ++++++++++++
 trace-events          |   9 +++
 4 files changed, 281 insertions(+)
 create mode 100644 hw/acpi/cpu.c
 create mode 100644 include/hw/acpi/cpu.h

diff --git a/hw/acpi/Makefile.objs b/hw/acpi/Makefile.objs
index 66bd727..f200419 100644
--- a/hw/acpi/Makefile.objs
+++ b/hw/acpi/Makefile.objs
@@ -2,6 +2,7 @@ common-obj-$(CONFIG_ACPI_X86) += core.o piix4.o pcihp.o
 common-obj-$(CONFIG_ACPI_X86_ICH) += ich9.o tco.o
 common-obj-$(CONFIG_ACPI_CPU_HOTPLUG) += cpu_hotplug.o
 common-obj-$(CONFIG_ACPI_MEMORY_HOTPLUG) += memory_hotplug.o memory_hotplug_acpi_table.o
+common-obj-$(CONFIG_ACPI_CPU_HOTPLUG) += cpu.o
 obj-$(CONFIG_ACPI_NVDIMM) += nvdimm.o
 common-obj-$(CONFIG_ACPI) += acpi_interface.o
 common-obj-$(CONFIG_ACPI) += bios-linker-loader.o
diff --git a/hw/acpi/cpu.c b/hw/acpi/cpu.c
new file mode 100644
index 0000000..2b4feb0
--- /dev/null
+++ b/hw/acpi/cpu.c
@@ -0,0 +1,218 @@
+#include "qemu/osdep.h"
+#include "hw/boards.h"
+#include "hw/acpi/cpu.h"
+#include "qapi/error.h"
+#include "trace.h"
+
+#define ACPI_CPU_HOTPLUG_REG_LEN 12
+#define ACPI_CPU_SELECTOR_OFFSET_WR 0
+#define ACPI_CPU_FLAGS_OFFSET_RW 4
+
+static uint64_t cpu_hotplug_rd(void *opaque, hwaddr addr, unsigned size)
+{
+    uint64_t val = ~0;
+    CPUHotplugState *cpu_st = opaque;
+    AcpiCpuStatus *cdev;
+
+    if (cpu_st->selector >= cpu_st->dev_count) {
+        return val;
+    }
+
+    cdev = &cpu_st->devs[cpu_st->selector];
+    switch (addr) {
+    case ACPI_CPU_FLAGS_OFFSET_RW: /* pack and return is_* fields */
+        val = 0;
+        val |= cdev->is_enabled   ? 1 : 0;
+        val |= cdev->is_inserting ? 2 : 0;
+        val |= cdev->is_removing  ? 4 : 0;
+        trace_cpuhp_acpi_read_flags(cpu_st->selector, val);
+        break;
+    default:
+        break;
+    }
+    return val;
+}
+
+static void cpu_hotplug_wr(void *opaque, hwaddr addr, uint64_t data,
+                           unsigned int size)
+{
+    CPUHotplugState *cpu_st = opaque;
+    AcpiCpuStatus *cdev;
+    Error *local_err = NULL;
+
+    assert(cpu_st->dev_count);
+
+    if (addr) {
+        if (cpu_st->selector >= cpu_st->dev_count) {
+            trace_cpuhp_acpi_invalid_idx_selected(cpu_st->selector);
+            return;
+        }
+    }
+
+    switch (addr) {
+    case ACPI_CPU_SELECTOR_OFFSET_WR: /* current CPU selector */
+        cpu_st->selector = data;
+        trace_cpuhp_acpi_write_idx(cpu_st->selector);
+        break;
+    case ACPI_CPU_FLAGS_OFFSET_RW: /* set is_* fields  */
+        cdev = &cpu_st->devs[cpu_st->selector];
+        if (data & 2) { /* clear insert event */
+            cdev->is_inserting = false;
+            trace_cpuhp_acpi_clear_inserting_evt(cpu_st->selector);
+        } else if (data & 4) { /* clear remove event */
+            cdev->is_removing = false;
+            trace_cpuhp_acpi_clear_remove_evt(cpu_st->selector);
+        } else if (data & 8) {
+            DeviceState *dev = NULL;
+            HotplugHandler *hotplug_ctrl = NULL;
+
+            if (!cdev->is_enabled) {
+                trace_cpuhp_acpi_ejecting_invalid_cpu(cpu_st->selector);
+                break;
+            }
+
+            trace_cpuhp_acpi_ejecting_cpu(cpu_st->selector);
+            dev = DEVICE(cdev->cpu);
+            hotplug_ctrl = qdev_get_hotplug_handler(dev);
+            hotplug_handler_unplug(hotplug_ctrl, dev, &local_err);
+            if (local_err) {
+                break;
+            }
+        }
+        break;
+    default:
+        break;
+    }
+    error_free(local_err);
+}
+
+static const MemoryRegionOps cpu_hotplug_ops = {
+    .read = cpu_hotplug_rd,
+    .write = cpu_hotplug_wr,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+    .valid = {
+        .min_access_size = 1,
+        .max_access_size = 4,
+    },
+};
+
+void cpu_hotplug_hw_init(MemoryRegion *as, Object *owner,
+                         CPUHotplugState *state, hwaddr base_addr)
+{
+    MachineState *machine = MACHINE(qdev_get_machine());
+    MachineClass *mc = MACHINE_GET_CLASS(machine);
+    CPUArchIdList *id_list;
+    int i;
+
+    id_list = mc->possible_cpu_arch_ids(machine);
+    state->dev_count = id_list->len;
+    state->devs = g_new0(typeof(*state->devs), state->dev_count);
+    for (i = 0; i < id_list->len; i++) {
+        state->devs[i].cpu =  id_list->cpus[i].cpu;
+        state->devs[i].arch_id = id_list->cpus[i].arch_id;
+        state->devs[i].is_enabled =  id_list->cpus[i].cpu ? true : false;
+    }
+    g_free(id_list);
+    memory_region_init_io(&state->ctrl_reg, owner, &cpu_hotplug_ops, state,
+                          "acpi-mem-hotplug", ACPI_CPU_HOTPLUG_REG_LEN);
+    memory_region_add_subregion(as, base_addr, &state->ctrl_reg);
+}
+
+static AcpiCpuStatus *get_cpu_status(CPUHotplugState *cpu_st, DeviceState *dev)
+{
+    CPUClass *k = CPU_GET_CLASS(dev);
+    uint64_t cpu_arch_id = k->get_arch_id(CPU(dev));
+    int i;
+
+    for (i = 0; i < cpu_st->dev_count; i++) {
+        if (cpu_arch_id == cpu_st->devs[i].arch_id) {
+            return &cpu_st->devs[i];
+        }
+    }
+    return NULL;
+}
+
+void acpi_cpu_plug_cb(HotplugHandler *hotplug_dev,
+                      CPUHotplugState *cpu_st, DeviceState *dev, Error **errp)
+{
+    AcpiCpuStatus *cdev;
+
+    if (!cpu_st->is_enabled) {
+        error_setg(errp, "acpi: CPU hotplug is not enabled on: %s",
+                   object_get_typename(OBJECT(hotplug_dev)));
+        return;
+    }
+
+    cdev = get_cpu_status(cpu_st, dev);
+    if (!cdev) {
+        return;
+    }
+
+    cdev->cpu = CPU(dev);
+    cdev->is_enabled = true;
+    if (dev->hotplugged) {
+        cdev->is_inserting = true;
+        ACPI_SEND_EVENT(hotplug_dev, ACPI_CPU_HOTPLUG_STATUS);
+    }
+}
+
+void acpi_cpu_unplug_request_cb(HotplugHandler *hotplug_dev,
+                                CPUHotplugState *cpu_st,
+                                DeviceState *dev, Error **errp)
+{
+    AcpiCpuStatus *cdev;
+
+    if (!cpu_st->is_enabled) {
+        error_setg(errp, "acpi: CPU hotplug is not enabled on: %s",
+                   object_get_typename(OBJECT(hotplug_dev)));
+        return;
+    }
+
+    cdev = get_cpu_status(cpu_st, dev);
+    if (!cdev) {
+        return;
+    }
+
+    cdev->is_removing = true;
+    ACPI_SEND_EVENT(hotplug_dev, ACPI_CPU_HOTPLUG_STATUS);
+}
+
+void acpi_cpu_unplug_cb(CPUHotplugState *cpu_st,
+                        DeviceState *dev, Error **errp)
+{
+    AcpiCpuStatus *cdev;
+
+    cdev = get_cpu_status(cpu_st, dev);
+    if (!cdev) {
+        return;
+    }
+
+    cdev->cpu = NULL;
+    cdev->is_enabled = false;
+}
+
+static const VMStateDescription vmstate_cpuhp_sts = {
+    .name = "CPU hotplug device state",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields      = (VMStateField[]) {
+        VMSTATE_BOOL(is_enabled, AcpiCpuStatus),
+        VMSTATE_BOOL(is_inserting, AcpiCpuStatus),
+        VMSTATE_BOOL(is_removing, AcpiCpuStatus),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+const VMStateDescription vmstate_cpu_hotplug = {
+    .name = "CPU hotplug state",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .minimum_version_id_old = 1,
+    .fields      = (VMStateField[]) {
+        VMSTATE_UINT32(selector, CPUHotplugState),
+        VMSTATE_STRUCT_VARRAY_POINTER_UINT32(devs, CPUHotplugState, dev_count,
+                                             vmstate_cpuhp_sts, AcpiCpuStatus),
+        VMSTATE_END_OF_LIST()
+    }
+};
diff --git a/include/hw/acpi/cpu.h b/include/hw/acpi/cpu.h
new file mode 100644
index 0000000..c746292
--- /dev/null
+++ b/include/hw/acpi/cpu.h
@@ -0,0 +1,53 @@
+/*
+ * QEMU ACPI hotplug utilities
+ *
+ * Copyright (C) 2016 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.
+ */
+#ifndef ACPI_CPU_H
+#define ACPI_CPU_H
+
+#include "hw/qdev-core.h"
+#include "hw/acpi/acpi.h"
+#include "hw/hotplug.h"
+
+typedef struct AcpiCpuStatus {
+    struct CPUState *cpu;
+    uint64_t arch_id;
+    bool is_enabled;
+    bool is_inserting;
+    bool is_removing;
+} AcpiCpuStatus;
+
+typedef struct CPUHotplugState {
+    MemoryRegion ctrl_reg;
+    bool is_enabled;
+    uint32_t selector;
+    uint32_t dev_count;
+    AcpiCpuStatus *devs;
+} CPUHotplugState;
+
+void acpi_cpu_plug_cb(HotplugHandler *hotplug_dev,
+                      CPUHotplugState *cpu_st, DeviceState *dev, Error **errp);
+
+void acpi_cpu_unplug_request_cb(HotplugHandler *hotplug_dev,
+                                CPUHotplugState *cpu_st,
+                                DeviceState *dev, Error **errp);
+
+void acpi_cpu_unplug_cb(CPUHotplugState *cpu_st,
+                        DeviceState *dev, Error **errp);
+
+void cpu_hotplug_hw_init(MemoryRegion *as, Object *owner,
+                         CPUHotplugState *state, hwaddr base_addr);
+
+extern const VMStateDescription vmstate_cpu_hotplug;
+#define VMSTATE_CPU_HOTPLUG(cpuhp, state) \
+    VMSTATE_STRUCT(cpuhp, state, 1, \
+                   vmstate_cpu_hotplug, CPUHotplugState)
+
+#endif
diff --git a/trace-events b/trace-events
index 8350743..9df9531 100644
--- a/trace-events
+++ b/trace-events
@@ -1909,3 +1909,12 @@ aspeed_vic_update_fiq(int flags) "Raising FIQ: %d"
 aspeed_vic_update_irq(int flags) "Raising IRQ: %d"
 aspeed_vic_read(uint64_t offset, unsigned size, uint32_t value) "From 0x%" PRIx64 " of size %u: 0x%" PRIx32
 aspeed_vic_write(uint64_t offset, unsigned size, uint32_t data) "To 0x%" PRIx64 " of size %u: 0x%" PRIx32
+
+# hw/acpi/cpu.c
+cpuhp_acpi_invalid_idx_selected(uint32_t idx) "0x%"PRIx32
+cpuhp_acpi_read_flags(uint32_t idx, uint8_t flags) "idx[0x%"PRIx32"] flags: 0x%"PRIx8
+cpuhp_acpi_clear_inserting_evt(uint32_t idx) "idx[0x%"PRIx32"]"
+cpuhp_acpi_clear_remove_evt(uint32_t idx) "idx[0x%"PRIx32"]"
+cpuhp_acpi_write_idx(uint32_t idx) "set active cpu idx: 0x%"PRIx32
+cpuhp_acpi_ejecting_invalid_cpu(uint32_t idx) "0x%"PRIx32
+cpuhp_acpi_ejecting_cpu(uint32_t idx) "0x%"PRIx32
-- 
1.8.3.1