xref: /openbmc/qemu/hw/s390x/sclpquiesce.c (revision 1fd6bb44)
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)
124