xref: /openbmc/qemu/hw/s390x/sclp.c (revision c71c3e99)
1 /*
2  * SCLP Support
3  *
4  * Copyright IBM, Corp. 2012
5  *
6  * Authors:
7  *  Christian Borntraeger <borntraeger@de.ibm.com>
8  *  Heinz Graalfs <graalfs@linux.vnet.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 
15 #include "cpu.h"
16 #include "sysemu/kvm.h"
17 #include "exec/memory.h"
18 
19 #include "hw/s390x/sclp.h"
20 
21 static inline S390SCLPDevice *get_event_facility(void)
22 {
23     ObjectProperty *op = object_property_find(qdev_get_machine(),
24                                               "s390-sclp-event-facility",
25                                               NULL);
26     assert(op);
27     return op->opaque;
28 }
29 
30 /* Provide information about the configuration, CPUs and storage */
31 static void read_SCP_info(SCCB *sccb)
32 {
33     ReadInfo *read_info = (ReadInfo *) sccb;
34     int shift = 0;
35 
36     while ((ram_size >> (20 + shift)) > 65535) {
37         shift++;
38     }
39     read_info->rnmax = cpu_to_be16(ram_size >> (20 + shift));
40     read_info->rnsize = 1 << shift;
41     sccb->h.response_code = cpu_to_be16(SCLP_RC_NORMAL_READ_COMPLETION);
42 }
43 
44 static void sclp_execute(SCCB *sccb, uint64_t code)
45 {
46     S390SCLPDevice *sdev = get_event_facility();
47 
48     switch (code) {
49     case SCLP_CMDW_READ_SCP_INFO:
50     case SCLP_CMDW_READ_SCP_INFO_FORCED:
51         read_SCP_info(sccb);
52         break;
53     default:
54         sdev->sclp_command_handler(sdev->ef, sccb, code);
55         break;
56     }
57 }
58 
59 int sclp_service_call(uint32_t sccb, uint64_t code)
60 {
61     int r = 0;
62     SCCB work_sccb;
63 
64     hwaddr sccb_len = sizeof(SCCB);
65 
66     /* first some basic checks on program checks */
67     if (cpu_physical_memory_is_io(sccb)) {
68         r = -PGM_ADDRESSING;
69         goto out;
70     }
71     if (sccb & ~0x7ffffff8ul) {
72         r = -PGM_SPECIFICATION;
73         goto out;
74     }
75 
76     /*
77      * we want to work on a private copy of the sccb, to prevent guests
78      * from playing dirty tricks by modifying the memory content after
79      * the host has checked the values
80      */
81     cpu_physical_memory_read(sccb, &work_sccb, sccb_len);
82 
83     /* Valid sccb sizes */
84     if (be16_to_cpu(work_sccb.h.length) < sizeof(SCCBHeader) ||
85         be16_to_cpu(work_sccb.h.length) > SCCB_SIZE) {
86         r = -PGM_SPECIFICATION;
87         goto out;
88     }
89 
90     sclp_execute((SCCB *)&work_sccb, code);
91 
92     cpu_physical_memory_write(sccb, &work_sccb,
93                               be16_to_cpu(work_sccb.h.length));
94 
95     sclp_service_interrupt(sccb);
96 
97 out:
98     return r;
99 }
100 
101 void sclp_service_interrupt(uint32_t sccb)
102 {
103     S390SCLPDevice *sdev = get_event_facility();
104     uint32_t param = sccb & ~3;
105 
106     /* Indicate whether an event is still pending */
107     param |= sdev->event_pending(sdev->ef) ? 1 : 0;
108 
109     if (!param) {
110         /* No need to send an interrupt, there's nothing to be notified about */
111         return;
112     }
113     s390_sclp_extint(param);
114 }
115 
116 /* qemu object creation and initialization functions */
117 
118 void s390_sclp_init(void)
119 {
120     DeviceState *dev  = qdev_create(NULL, "s390-sclp-event-facility");
121 
122     object_property_add_child(qdev_get_machine(), "s390-sclp-event-facility",
123                               OBJECT(dev), NULL);
124     qdev_init_nofail(dev);
125 }
126 
127 static int s390_sclp_dev_init(SysBusDevice *dev)
128 {
129     int r;
130     S390SCLPDevice *sdev = (S390SCLPDevice *)dev;
131     S390SCLPDeviceClass *sclp = SCLP_S390_DEVICE_GET_CLASS(dev);
132 
133     r = sclp->init(sdev);
134     if (!r) {
135         assert(sdev->event_pending);
136         assert(sdev->sclp_command_handler);
137     }
138 
139     return r;
140 }
141 
142 static void s390_sclp_device_class_init(ObjectClass *klass, void *data)
143 {
144     SysBusDeviceClass *dc = SYS_BUS_DEVICE_CLASS(klass);
145 
146     dc->init = s390_sclp_dev_init;
147 }
148 
149 static const TypeInfo s390_sclp_device_info = {
150     .name = TYPE_DEVICE_S390_SCLP,
151     .parent = TYPE_SYS_BUS_DEVICE,
152     .instance_size = sizeof(S390SCLPDevice),
153     .class_init = s390_sclp_device_class_init,
154     .class_size = sizeof(S390SCLPDeviceClass),
155     .abstract = true,
156 };
157 
158 static void s390_sclp_register_types(void)
159 {
160     type_register_static(&s390_sclp_device_info);
161 }
162 
163 type_init(s390_sclp_register_types)
164