xref: /openbmc/qemu/hw/s390x/sclpcpu.c (revision a6caeee8)
1 /*
2  * SCLP event type
3  *    Signal CPU - Trigger SCLP interrupt for system CPU configure or
4  *    de-configure
5  *
6  * Copyright IBM, Corp. 2013
7  *
8  * Authors:
9  *  Thang Pham <thang.pham@us.ibm.com>
10  *
11  * This work is licensed under the terms of the GNU GPL, version 2 or (at your
12  * option) any later version.  See the COPYING file in the top-level directory.
13  *
14  */
15 
16 #include "qemu/osdep.h"
17 #include "hw/s390x/sclp.h"
18 #include "qemu/module.h"
19 #include "hw/s390x/event-facility.h"
20 #include "sysemu/cpus.h"
21 
22 typedef struct ConfigMgtData {
23     EventBufferHeader ebh;
24     uint8_t reserved;
25     uint8_t event_qualifier;
26 } QEMU_PACKED ConfigMgtData;
27 
28 #define EVENT_QUAL_CPU_CHANGE  1
29 
30 void raise_irq_cpu_hotplug(void)
31 {
32     Object *obj = object_resolve_path_type("", TYPE_SCLP_CPU_HOTPLUG, NULL);
33 
34     SCLP_EVENT(obj)->event_pending = true;
35 
36     /* Trigger SCLP read operation */
37     sclp_service_interrupt(0);
38 }
39 
40 static sccb_mask_t send_mask(void)
41 {
42     return SCLP_EVENT_MASK_CONFIG_MGT_DATA;
43 }
44 
45 static sccb_mask_t receive_mask(void)
46 {
47     return 0;
48 }
49 
50 static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
51                            int *slen)
52 {
53     ConfigMgtData *cdata = (ConfigMgtData *) evt_buf_hdr;
54     if (*slen < sizeof(ConfigMgtData)) {
55         return 0;
56     }
57 
58     /* Event is no longer pending */
59     if (!event->event_pending) {
60         return 0;
61     }
62     event->event_pending = false;
63 
64     /* Event header data */
65     cdata->ebh.length = cpu_to_be16(sizeof(ConfigMgtData));
66     cdata->ebh.type = SCLP_EVENT_CONFIG_MGT_DATA;
67     cdata->ebh.flags |= SCLP_EVENT_BUFFER_ACCEPTED;
68 
69     /* Trigger a rescan of CPUs by setting event qualifier */
70     cdata->event_qualifier = EVENT_QUAL_CPU_CHANGE;
71     *slen -= sizeof(ConfigMgtData);
72 
73     return 1;
74 }
75 
76 static void cpu_class_init(ObjectClass *oc, void *data)
77 {
78     SCLPEventClass *k = SCLP_EVENT_CLASS(oc);
79     DeviceClass *dc = DEVICE_CLASS(oc);
80 
81     k->get_send_mask = send_mask;
82     k->get_receive_mask = receive_mask;
83     k->read_event_data = read_event_data;
84     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
85     /*
86      * Reason: raise_irq_cpu_hotplug() depends on an unique
87      * TYPE_SCLP_CPU_HOTPLUG device, which is already created
88      * by the sclp event facility
89      */
90     dc->user_creatable = false;
91 }
92 
93 static const TypeInfo sclp_cpu_info = {
94     .name          = TYPE_SCLP_CPU_HOTPLUG,
95     .parent        = TYPE_SCLP_EVENT,
96     .instance_size = sizeof(SCLPEvent),
97     .class_init    = cpu_class_init,
98     .class_size    = sizeof(SCLPEventClass),
99 };
100 
101 static void sclp_cpu_register_types(void)
102 {
103     type_register_static(&sclp_cpu_info);
104 }
105 
106 type_init(sclp_cpu_register_types)
107