xref: /openbmc/qemu/hw/s390x/3270-ccw.c (revision 10df8ff1)
1 /*
2  * Emulated ccw-attached 3270 implementation
3  *
4  * Copyright 2017 IBM Corp.
5  * Author(s): Yang Chen <bjcyang@linux.vnet.ibm.com>
6  *            Jing Liu <liujbjl@linux.vnet.ibm.com>
7  *
8  * This work is licensed under the terms of the GNU GPL, version 2 or (at
9  * your option) any later version. See the COPYING file in the top-level
10  * directory.
11  */
12 #include "qemu/osdep.h"
13 #include "qapi/error.h"
14 #include "qemu/module.h"
15 #include "cpu.h"
16 #include "hw/s390x/css.h"
17 #include "hw/s390x/css-bridge.h"
18 #include "hw/s390x/3270-ccw.h"
19 
20 /* Handle READ ccw commands from guest */
21 static int handle_payload_3270_read(EmulatedCcw3270Device *dev, CCW1 *ccw)
22 {
23     EmulatedCcw3270Class *ck = EMULATED_CCW_3270_GET_CLASS(dev);
24     CcwDevice *ccw_dev = CCW_DEVICE(dev);
25     int len;
26 
27     if (!ccw->cda) {
28         return -EFAULT;
29     }
30 
31     len = ck->read_payload_3270(dev);
32     ccw_dev->sch->curr_status.scsw.count = ccw->count - len;
33 
34     return 0;
35 }
36 
37 /* Handle WRITE ccw commands to write data to client */
38 static int handle_payload_3270_write(EmulatedCcw3270Device *dev, CCW1 *ccw)
39 {
40     EmulatedCcw3270Class *ck = EMULATED_CCW_3270_GET_CLASS(dev);
41     CcwDevice *ccw_dev = CCW_DEVICE(dev);
42     int len;
43 
44     if (!ccw->cda) {
45         return -EFAULT;
46     }
47 
48     len = ck->write_payload_3270(dev, ccw->cmd_code);
49 
50     if (len <= 0) {
51         return -EIO;
52     }
53 
54     ccw_dev->sch->curr_status.scsw.count = ccw->count - len;
55     return 0;
56 }
57 
58 static int emulated_ccw_3270_cb(SubchDev *sch, CCW1 ccw)
59 {
60     int rc = 0;
61     EmulatedCcw3270Device *dev = sch->driver_data;
62 
63     switch (ccw.cmd_code) {
64     case TC_WRITESF:
65     case TC_WRITE:
66     case TC_EWRITE:
67     case TC_EWRITEA:
68         rc = handle_payload_3270_write(dev, &ccw);
69         break;
70     case TC_RDBUF:
71     case TC_READMOD:
72         rc = handle_payload_3270_read(dev, &ccw);
73         break;
74     default:
75         rc = -ENOSYS;
76         break;
77     }
78 
79     if (rc == -EIO) {
80         /* I/O error, specific devices generate specific conditions */
81         SCSW *s = &sch->curr_status.scsw;
82 
83         sch->curr_status.scsw.dstat = SCSW_DSTAT_UNIT_CHECK;
84         sch->sense_data[0] = 0x40;    /* intervention-req */
85         s->ctrl &= ~SCSW_ACTL_START_PEND;
86         s->ctrl &= ~SCSW_CTRL_MASK_STCTL;
87         s->ctrl |= SCSW_STCTL_PRIMARY | SCSW_STCTL_SECONDARY |
88                    SCSW_STCTL_ALERT | SCSW_STCTL_STATUS_PEND;
89     }
90 
91     return rc;
92 }
93 
94 static void emulated_ccw_3270_realize(DeviceState *ds, Error **errp)
95 {
96     uint16_t chpid;
97     EmulatedCcw3270Device *dev = EMULATED_CCW_3270(ds);
98     EmulatedCcw3270Class *ck = EMULATED_CCW_3270_GET_CLASS(dev);
99     CcwDevice *cdev = CCW_DEVICE(ds);
100     CCWDeviceClass *cdk = CCW_DEVICE_GET_CLASS(cdev);
101     SubchDev *sch;
102     Error *err = NULL;
103 
104     sch = css_create_sch(cdev->devno, errp);
105     if (!sch) {
106         return;
107     }
108 
109     if (!ck->init) {
110         goto out_err;
111     }
112 
113     sch->driver_data = dev;
114     cdev->sch = sch;
115     chpid = css_find_free_chpid(sch->cssid);
116 
117     if (chpid > MAX_CHPID) {
118         error_setg(&err, "No available chpid to use.");
119         goto out_err;
120     }
121 
122     sch->id.reserved = 0xff;
123     sch->id.cu_type = EMULATED_CCW_3270_CU_TYPE;
124     css_sch_build_virtual_schib(sch, (uint8_t)chpid,
125                                 EMULATED_CCW_3270_CHPID_TYPE);
126     sch->do_subchannel_work = do_subchannel_work_virtual;
127     sch->ccw_cb = emulated_ccw_3270_cb;
128 
129     ck->init(dev, &err);
130     if (err) {
131         goto out_err;
132     }
133 
134     cdk->realize(cdev, &err);
135     if (err) {
136         goto out_err;
137     }
138 
139     return;
140 
141 out_err:
142     error_propagate(errp, err);
143     css_subch_assign(sch->cssid, sch->ssid, sch->schid, sch->devno, NULL);
144     cdev->sch = NULL;
145     g_free(sch);
146 }
147 
148 static Property emulated_ccw_3270_properties[] = {
149     DEFINE_PROP_END_OF_LIST(),
150 };
151 
152 static void emulated_ccw_3270_class_init(ObjectClass *klass, void *data)
153 {
154     DeviceClass *dc = DEVICE_CLASS(klass);
155 
156     dc->props = emulated_ccw_3270_properties;
157     dc->bus_type = TYPE_VIRTUAL_CSS_BUS;
158     dc->realize = emulated_ccw_3270_realize;
159     dc->hotpluggable = false;
160     set_bit(DEVICE_CATEGORY_DISPLAY, dc->categories);
161 }
162 
163 static const TypeInfo emulated_ccw_3270_info = {
164     .name = TYPE_EMULATED_CCW_3270,
165     .parent = TYPE_CCW_DEVICE,
166     .instance_size = sizeof(EmulatedCcw3270Device),
167     .class_init = emulated_ccw_3270_class_init,
168     .class_size = sizeof(EmulatedCcw3270Class),
169     .abstract = true,
170 };
171 
172 static void emulated_ccw_register(void)
173 {
174     type_register_static(&emulated_ccw_3270_info);
175 }
176 
177 type_init(emulated_ccw_register)
178