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 int event_type(void)
  26 {
  27     return 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 typedef struct QuiesceNotifier QuiesceNotifier;
  69
  70 static struct QuiesceNotifier {
  71     Notifier notifier;
  72     SCLPEvent *event;
  73 } qn;
  74
  75 static void quiesce_powerdown_req(Notifier *n, void *opaque)
  76 {
  77     QuiesceNotifier *qn = container_of(n, QuiesceNotifier, notifier);
  78     SCLPEvent *event = qn->event;
  79
  80     event->event_pending = true;
  81     /* trigger SCLP read operation */
  82     sclp_service_interrupt(0);
  83 }
  84
  85 static int quiesce_init(SCLPEvent *event)
  86 {
  87     event->event_type = SCLP_EVENT_SIGNAL_QUIESCE;
  88
  89     qn.notifier.notify = quiesce_powerdown_req;
  90     qn.event = event;
  91
  92     qemu_register_powerdown_notifier(&qn.notifier);
  93
  94     return 0;
  95 }
  96
  97 static void quiesce_class_init(ObjectClass *klass, void *data)
  98 {
  99     SCLPEventClass *k = SCLP_EVENT_CLASS(klass);
 100
 101     k->init = quiesce_init;
 102
 103     k->get_send_mask = send_mask;
 104     k->get_receive_mask = receive_mask;
 105     k->event_type = event_type;
 106     k->read_event_data = read_event_data;
 107     k->write_event_data = NULL;
 108 }
 109
 110 static const TypeInfo sclp_quiesce_info = {
 111     .name          = "sclpquiesce",
 112     .parent        = TYPE_SCLP_EVENT,
 113     .instance_size = sizeof(SCLPEvent),
 114     .class_init    = quiesce_class_init,
 115     .class_size    = sizeof(SCLPEventClass),
 116 };
 117
 118 static void register_types(void)
 119 {
 120     type_register_static(&sclp_quiesce_info);
 121 }
 122
 123 type_init(register_types)