xref: /openbmc/qemu/hw/s390x/sclpcpu.c (revision 59a3a1c0)
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 "cpu.h"
21 #include "sysemu/cpus.h"
22 
23 typedef struct ConfigMgtData {
24     EventBufferHeader ebh;
25     uint8_t reserved;
26     uint8_t event_qualifier;
27 } QEMU_PACKED ConfigMgtData;
28 
29 #define EVENT_QUAL_CPU_CHANGE  1
30 
31 void raise_irq_cpu_hotplug(void)
32 {
33     Object *obj = object_resolve_path_type("", TYPE_SCLP_CPU_HOTPLUG, NULL);
34 
35     SCLP_EVENT(obj)->event_pending = true;
36 
37     /* Trigger SCLP read operation */
38     sclp_service_interrupt(0);
39 }
40 
41 static sccb_mask_t send_mask(void)
42 {
43     return SCLP_EVENT_MASK_CONFIG_MGT_DATA;
44 }
45 
46 static sccb_mask_t receive_mask(void)
47 {
48     return 0;
49 }
50 
51 static int read_event_data(SCLPEvent *event, EventBufferHeader *evt_buf_hdr,
52                            int *slen)
53 {
54     ConfigMgtData *cdata = (ConfigMgtData *) evt_buf_hdr;
55     if (*slen < sizeof(ConfigMgtData)) {
56         return 0;
57     }
58 
59     /* Event is no longer pending */
60     if (!event->event_pending) {
61         return 0;
62     }
63     event->event_pending = false;
64 
65     /* Event header data */
66     cdata->ebh.length = cpu_to_be16(sizeof(ConfigMgtData));
67     cdata->ebh.type = SCLP_EVENT_CONFIG_MGT_DATA;
68     cdata->ebh.flags |= SCLP_EVENT_BUFFER_ACCEPTED;
69 
70     /* Trigger a rescan of CPUs by setting event qualifier */
71     cdata->event_qualifier = EVENT_QUAL_CPU_CHANGE;
72     *slen -= sizeof(ConfigMgtData);
73 
74     return 1;
75 }
76 
77 static void cpu_class_init(ObjectClass *oc, void *data)
78 {
79     SCLPEventClass *k = SCLP_EVENT_CLASS(oc);
80     DeviceClass *dc = DEVICE_CLASS(oc);
81 
82     k->get_send_mask = send_mask;
83     k->get_receive_mask = receive_mask;
84     k->read_event_data = read_event_data;
85     set_bit(DEVICE_CATEGORY_MISC, dc->categories);
86     /*
87      * Reason: raise_irq_cpu_hotplug() depends on an unique
88      * TYPE_SCLP_CPU_HOTPLUG device, which is already created
89      * by the sclp event facility
90      */
91     dc->user_creatable = false;
92 }
93 
94 static const TypeInfo sclp_cpu_info = {
95     .name          = TYPE_SCLP_CPU_HOTPLUG,
96     .parent        = TYPE_SCLP_EVENT,
97     .instance_size = sizeof(SCLPEvent),
98     .class_init    = cpu_class_init,
99     .class_size    = sizeof(SCLPEventClass),
100 };
101 
102 static void sclp_cpu_register_types(void)
103 {
104     type_register_static(&sclp_cpu_info);
105 }
106 
107 type_init(sclp_cpu_register_types)
108