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 <hw/qdev.h>
  15 #include "sysemu/sysemu.h"
  16 #include "hw/s390x/sclp.h"
  17 #include "hw/s390x/event-facility.h"
  18
  19 typedef struct SignalQuiesce {
  20     EventBufferHeader ebh;
  21     uint16_t timeout;
  22     uint8_t unit;
  23 } QEMU_PACKED SignalQuiesce;
  24
  25 static bool can_handle_event(uint8_t type)
  26 {
  27     return type == SCLP_EVENT_SIGNAL_QUIESCE;
  28 }
  29
  30 static unsigned int send_mask(void)
  31 {
  32     return SCLP_EVENT_MASK_SIGNAL_QUIESCE;
  33 }
  34
  35 static unsigned int receive_mask(void)
  36 {
  37     return 0;
  38 }
  39
  40 static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
  41                            int *slen)
  42 {
  43     SignalQuiesce *sq = (SignalQuiesce *) evt_buf_hdr;
  44
  45     if (*slen < sizeof(SignalQuiesce)) {
  46         return 0;
  47     }
  48
  49     if (!event->event_pending) {
  50         return 0;
  51     }
  52     event->event_pending = false;
  53
  54     sq->ebh.length = cpu_to_be16(sizeof(SignalQuiesce));
  55     sq->ebh.type = SCLP_EVENT_SIGNAL_QUIESCE;
  56     sq->ebh.flags |= SCLP_EVENT_BUFFER_ACCEPTED;
  57     /*
  58      * system_powerdown does not have a timeout. Fortunately the
  59      * timeout value is currently ignored by Linux, anyway
  60      */
  61     sq->timeout = cpu_to_be16(0);
  62     sq->unit = cpu_to_be16(0);
  63     *slen -= sizeof(SignalQuiesce);
  64
  65     return 1;
  66 }
  67
  68 static const VMStateDescription vmstate_sclpquiesce = {
  69     .name = "sclpquiesce",
  70     .version_id = 0,
  71     .minimum_version_id = 0,
  72     .minimum_version_id_old = 0,
  73     .fields      = (VMStateField[]) {
  74         VMSTATE_BOOL(event_pending, SCLPEvent),
  75         VMSTATE_END_OF_LIST()
  76      }
  77 };
  78
  79 typedef struct QuiesceNotifier QuiesceNotifier;
  80
  81 static struct QuiesceNotifier {
  82     Notifier notifier;
  83     SCLPEvent *event;
  84 } qn;
  85
  86 static 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
  96 static 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
 106 static void quiesce_reset(DeviceState *dev)
 107 {
 108    SCLPEvent *event = SCLP_EVENT(dev);
 109
 110    event->event_pending = false;
 111 }
 112
 113 static 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     k->init = quiesce_init;
 121
 122     k->get_send_mask = send_mask;
 123     k->get_receive_mask = receive_mask;
 124     k->can_handle_event = can_handle_event;
 125     k->read_event_data = read_event_data;
 126     k->write_event_data = NULL;
 127 }
 128
 129 static const TypeInfo sclp_quiesce_info = {
 130     .name          = "sclpquiesce",
 131     .parent        = TYPE_SCLP_EVENT,
 132     .instance_size = sizeof(SCLPEvent),
 133     .class_init    = quiesce_class_init,
 134     .class_size    = sizeof(SCLPEventClass),
 135 };
 136
 137 static void register_types(void)
 138 {
 139     type_register_static(&sclp_quiesce_info);
 140 }
 141
 142 type_init(register_types)