LXR qemu/hw/s390x/sclpquiesce.c

   1/*
   2 * SCLP event type
   3 *    Signal Quiesce - trigger system powerdown request
   4 *
   5 * Copyright IBM, Corp. 2012
   6 *
   7 * Authors:
   8 *  Heinz Graalfs <graalfs@de.ibm.com>
   9 *
  10 * This work is licensed under the terms of the GNU GPL, version 2 or (at your
  11 * option) any later version.  See the COPYING file in the top-level directory.
  12 *
  13 */
  14#include "qemu/osdep.h"
  15#include "hw/qdev.h"
  16#include "sysemu/sysemu.h"
  17#include "hw/s390x/sclp.h"
  18#include "hw/s390x/event-facility.h"
  19
  20typedef struct SignalQuiesce {
  21    EventBufferHeader ebh;
  22    uint16_t timeout;
  23    uint8_t unit;
  24} QEMU_PACKED SignalQuiesce;
  25
  26static bool can_handle_event(uint8_t type)
  27{
  28    return type == SCLP_EVENT_SIGNAL_QUIESCE;
  29}
  30
  31static sccb_mask_t send_mask(void)
  32{
  33    return SCLP_EVENT_MASK_SIGNAL_QUIESCE;
  34}
  35
  36static sccb_mask_t receive_mask(void)
  37{
  38    return 0;
  39}
  40
  41static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
  42                           int *slen)
  43{
  44    SignalQuiesce *sq = (SignalQuiesce *) evt_buf_hdr;
  45
  46    if (*slen < sizeof(SignalQuiesce)) {
  47        return 0;
  48    }
  49
  50    if (!event->event_pending) {
  51        return 0;
  52    }
  53    event->event_pending = false;
  54
  55    sq->ebh.length = cpu_to_be16(sizeof(SignalQuiesce));
  56    sq->ebh.type = SCLP_EVENT_SIGNAL_QUIESCE;
  57    sq->ebh.flags |= SCLP_EVENT_BUFFER_ACCEPTED;
  58    /*
  59     * system_powerdown does not have a timeout. Fortunately the
  60     * timeout value is currently ignored by Linux, anyway
  61     */
  62    sq->timeout = cpu_to_be16(0);
  63    sq->unit = cpu_to_be16(0);
  64    *slen -= sizeof(SignalQuiesce);
  65
  66    return 1;
  67}
  68
  69static const VMStateDescription vmstate_sclpquiesce = {
  70    .name = TYPE_SCLP_QUIESCE,
  71    .version_id = 0,
  72    .minimum_version_id = 0,
  73    .fields = (VMStateField[]) {
  74        VMSTATE_BOOL(event_pending, SCLPEvent),
  75        VMSTATE_END_OF_LIST()
  76     }
  77};
  78
  79typedef struct QuiesceNotifier QuiesceNotifier;
  80
  81static struct QuiesceNotifier {
  82    Notifier notifier;
  83    SCLPEvent *event;
  84} qn;
  85
  86static void quiesce_powerdown_req(Notifier *n, void *opaque)
  87{
  88    QuiesceNotifier *qn = container_of(n, QuiesceNotifier, notifier);
  89    SCLPEvent *event = qn->event;
  90
  91    event->event_pending = true;
  92    /* trigger SCLP read operation */
  93    sclp_service_interrupt(0);
  94}
  95
  96static int quiesce_init(SCLPEvent *event)
  97{
  98    qn.notifier.notify = quiesce_powerdown_req;
  99    qn.event = event;
 100
 101    qemu_register_powerdown_notifier(&qn.notifier);
 102
 103    return 0;
 104}
 105
 106static void quiesce_reset(DeviceState *dev)
 107{
 108   SCLPEvent *event = SCLP_EVENT(dev);
 109
 110   event->event_pending = false;
 111}
 112
 113static void quiesce_class_init(ObjectClass *klass, void *data)
 114{
 115    DeviceClass *dc = DEVICE_CLASS(klass);
 116    SCLPEventClass *k = SCLP_EVENT_CLASS(klass);
 117
 118    dc->reset = quiesce_reset;
 119    dc->vmsd = &vmstate_sclpquiesce;
 120    set_bit(DEVICE_CATEGORY_MISC, dc->categories);
 121    /*
 122     * Reason: This is just an internal device - the notifier should
 123     * not be registered multiple times in quiesce_init()
 124     */
 125    dc->user_creatable = false;
 126
 127    k->init = quiesce_init;
 128    k->get_send_mask = send_mask;
 129    k->get_receive_mask = receive_mask;
 130    k->can_handle_event = can_handle_event;
 131    k->read_event_data = read_event_data;
 132    k->write_event_data = NULL;
 133}
 134
 135static const TypeInfo sclp_quiesce_info = {
 136    .name          = TYPE_SCLP_QUIESCE,
 137    .parent        = TYPE_SCLP_EVENT,
 138    .instance_size = sizeof(SCLPEvent),
 139    .class_init    = quiesce_class_init,
 140    .class_size    = sizeof(SCLPEventClass),
 141};
 142
 143static void register_types(void)
 144{
 145    type_register_static(&sclp_quiesce_info);
 146}
 147
 148type_init(register_types)
 149