xref: /openbmc/qemu/hw/ipmi/ipmi_bmc_extern.c (revision e4370165)
1 /*
2  * IPMI BMC external connection
3  *
4  * Copyright (c) 2015 Corey Minyard, MontaVista Software, LLC
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 
25 /*
26  * This is designed to connect with OpenIPMI's lanserv serial interface
27  * using the "VM" connection type.  See that for details.
28  */
29 
30 #include "qemu/osdep.h"
31 #include "qapi/error.h"
32 #include "qemu/timer.h"
33 #include "sysemu/char.h"
34 #include "sysemu/sysemu.h"
35 #include "hw/ipmi/ipmi.h"
36 
37 #define VM_MSG_CHAR        0xA0 /* Marks end of message */
38 #define VM_CMD_CHAR        0xA1 /* Marks end of a command */
39 #define VM_ESCAPE_CHAR     0xAA /* Set bit 4 from the next byte to 0 */
40 
41 #define VM_PROTOCOL_VERSION        1
42 #define VM_CMD_VERSION             0xff /* A version number byte follows */
43 #define VM_CMD_NOATTN              0x00
44 #define VM_CMD_ATTN                0x01
45 #define VM_CMD_ATTN_IRQ            0x02
46 #define VM_CMD_POWEROFF            0x03
47 #define VM_CMD_RESET               0x04
48 #define VM_CMD_ENABLE_IRQ          0x05 /* Enable/disable the messaging irq */
49 #define VM_CMD_DISABLE_IRQ         0x06
50 #define VM_CMD_SEND_NMI            0x07
51 #define VM_CMD_CAPABILITIES        0x08
52 #define   VM_CAPABILITIES_POWER    0x01
53 #define   VM_CAPABILITIES_RESET    0x02
54 #define   VM_CAPABILITIES_IRQ      0x04
55 #define   VM_CAPABILITIES_NMI      0x08
56 #define   VM_CAPABILITIES_ATTN     0x10
57 #define VM_CMD_FORCEOFF            0x09
58 
59 #define TYPE_IPMI_BMC_EXTERN "ipmi-bmc-extern"
60 #define IPMI_BMC_EXTERN(obj) OBJECT_CHECK(IPMIBmcExtern, (obj), \
61                                         TYPE_IPMI_BMC_EXTERN)
62 typedef struct IPMIBmcExtern {
63     IPMIBmc parent;
64 
65     CharBackend chr;
66 
67     bool connected;
68 
69     unsigned char inbuf[MAX_IPMI_MSG_SIZE + 2];
70     unsigned int inpos;
71     bool in_escape;
72     bool in_too_many;
73     bool waiting_rsp;
74     bool sending_cmd;
75 
76     unsigned char outbuf[(MAX_IPMI_MSG_SIZE + 2) * 2 + 1];
77     unsigned int outpos;
78     unsigned int outlen;
79 
80     struct QEMUTimer *extern_timer;
81 
82     /* A reset event is pending to be sent upstream. */
83     bool send_reset;
84 } IPMIBmcExtern;
85 
86 static int can_receive(void *opaque);
87 static void receive(void *opaque, const uint8_t *buf, int size);
88 static void chr_event(void *opaque, int event);
89 
90 static unsigned char
91 ipmb_checksum(const unsigned char *data, int size, unsigned char start)
92 {
93         unsigned char csum = start;
94 
95         for (; size > 0; size--, data++) {
96                 csum += *data;
97         }
98         return csum;
99 }
100 
101 static void continue_send(IPMIBmcExtern *ibe)
102 {
103     int ret;
104     if (ibe->outlen == 0) {
105         goto check_reset;
106     }
107  send:
108     ret = qemu_chr_fe_write(&ibe->chr, ibe->outbuf + ibe->outpos,
109                             ibe->outlen - ibe->outpos);
110     if (ret > 0) {
111         ibe->outpos += ret;
112     }
113     if (ibe->outpos < ibe->outlen) {
114         /* Not fully transmitted, try again in a 10ms */
115         timer_mod_ns(ibe->extern_timer,
116                      qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 10000000);
117     } else {
118         /* Sent */
119         ibe->outlen = 0;
120         ibe->outpos = 0;
121         if (!ibe->sending_cmd) {
122             ibe->waiting_rsp = true;
123         } else {
124             ibe->sending_cmd = false;
125         }
126     check_reset:
127         if (ibe->connected && ibe->send_reset) {
128             /* Send the reset */
129             ibe->outbuf[0] = VM_CMD_RESET;
130             ibe->outbuf[1] = VM_CMD_CHAR;
131             ibe->outlen = 2;
132             ibe->outpos = 0;
133             ibe->send_reset = false;
134             ibe->sending_cmd = true;
135             goto send;
136         }
137 
138         if (ibe->waiting_rsp) {
139             /* Make sure we get a response within 4 seconds. */
140             timer_mod_ns(ibe->extern_timer,
141                          qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 4000000000ULL);
142         }
143     }
144     return;
145 }
146 
147 static void extern_timeout(void *opaque)
148 {
149     IPMIBmcExtern *ibe = opaque;
150     IPMIInterface *s = ibe->parent.intf;
151 
152     if (ibe->connected) {
153         if (ibe->waiting_rsp && (ibe->outlen == 0)) {
154             IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
155             /* The message response timed out, return an error. */
156             ibe->waiting_rsp = false;
157             ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
158             ibe->inbuf[2] = ibe->outbuf[2];
159             ibe->inbuf[3] = IPMI_CC_TIMEOUT;
160             k->handle_rsp(s, ibe->outbuf[0], ibe->inbuf + 1, 3);
161         } else {
162             continue_send(ibe);
163         }
164     }
165 }
166 
167 static void addchar(IPMIBmcExtern *ibe, unsigned char ch)
168 {
169     switch (ch) {
170     case VM_MSG_CHAR:
171     case VM_CMD_CHAR:
172     case VM_ESCAPE_CHAR:
173         ibe->outbuf[ibe->outlen] = VM_ESCAPE_CHAR;
174         ibe->outlen++;
175         ch |= 0x10;
176         /* No break */
177 
178     default:
179         ibe->outbuf[ibe->outlen] = ch;
180         ibe->outlen++;
181     }
182 }
183 
184 static void ipmi_bmc_extern_handle_command(IPMIBmc *b,
185                                        uint8_t *cmd, unsigned int cmd_len,
186                                        unsigned int max_cmd_len,
187                                        uint8_t msg_id)
188 {
189     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(b);
190     IPMIInterface *s = ibe->parent.intf;
191     uint8_t err = 0, csum;
192     unsigned int i;
193 
194     if (ibe->outlen) {
195         /* We already have a command queued.  Shouldn't ever happen. */
196         fprintf(stderr, "IPMI KCS: Got command when not finished with the"
197                 " previous command\n");
198         abort();
199     }
200 
201     /* If it's too short or it was truncated, return an error. */
202     if (cmd_len < 2) {
203         err = IPMI_CC_REQUEST_DATA_LENGTH_INVALID;
204     } else if ((cmd_len > max_cmd_len) || (cmd_len > MAX_IPMI_MSG_SIZE)) {
205         err = IPMI_CC_REQUEST_DATA_TRUNCATED;
206     } else if (!ibe->connected) {
207         err = IPMI_CC_BMC_INIT_IN_PROGRESS;
208     }
209     if (err) {
210         IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
211         unsigned char rsp[3];
212         rsp[0] = cmd[0] | 0x04;
213         rsp[1] = cmd[1];
214         rsp[2] = err;
215         ibe->waiting_rsp = false;
216         k->handle_rsp(s, msg_id, rsp, 3);
217         goto out;
218     }
219 
220     addchar(ibe, msg_id);
221     for (i = 0; i < cmd_len; i++) {
222         addchar(ibe, cmd[i]);
223     }
224     csum = ipmb_checksum(&msg_id, 1, 0);
225     addchar(ibe, -ipmb_checksum(cmd, cmd_len, csum));
226 
227     ibe->outbuf[ibe->outlen] = VM_MSG_CHAR;
228     ibe->outlen++;
229 
230     /* Start the transmit */
231     continue_send(ibe);
232 
233  out:
234     return;
235 }
236 
237 static void handle_hw_op(IPMIBmcExtern *ibe, unsigned char hw_op)
238 {
239     IPMIInterface *s = ibe->parent.intf;
240     IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
241 
242     switch (hw_op) {
243     case VM_CMD_VERSION:
244         /* We only support one version at this time. */
245         break;
246 
247     case VM_CMD_NOATTN:
248         k->set_atn(s, 0, 0);
249         break;
250 
251     case VM_CMD_ATTN:
252         k->set_atn(s, 1, 0);
253         break;
254 
255     case VM_CMD_ATTN_IRQ:
256         k->set_atn(s, 1, 1);
257         break;
258 
259     case VM_CMD_POWEROFF:
260         k->do_hw_op(s, IPMI_POWEROFF_CHASSIS, 0);
261         break;
262 
263     case VM_CMD_RESET:
264         k->do_hw_op(s, IPMI_RESET_CHASSIS, 0);
265         break;
266 
267     case VM_CMD_ENABLE_IRQ:
268         k->set_irq_enable(s, 1);
269         break;
270 
271     case VM_CMD_DISABLE_IRQ:
272         k->set_irq_enable(s, 0);
273         break;
274 
275     case VM_CMD_SEND_NMI:
276         k->do_hw_op(s, IPMI_SEND_NMI, 0);
277         break;
278 
279     case VM_CMD_FORCEOFF:
280         qemu_system_shutdown_request();
281         break;
282     }
283 }
284 
285 static void handle_msg(IPMIBmcExtern *ibe)
286 {
287     IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(ibe->parent.intf);
288 
289     if (ibe->in_escape) {
290         ipmi_debug("msg escape not ended\n");
291         return;
292     }
293     if (ibe->inpos < 5) {
294         ipmi_debug("msg too short\n");
295         return;
296     }
297     if (ibe->in_too_many) {
298         ibe->inbuf[3] = IPMI_CC_REQUEST_DATA_TRUNCATED;
299         ibe->inpos = 4;
300     } else if (ipmb_checksum(ibe->inbuf, ibe->inpos, 0) != 0) {
301         ipmi_debug("msg checksum failure\n");
302         return;
303     } else {
304         ibe->inpos--; /* Remove checkum */
305     }
306 
307     timer_del(ibe->extern_timer);
308     ibe->waiting_rsp = false;
309     k->handle_rsp(ibe->parent.intf, ibe->inbuf[0], ibe->inbuf + 1, ibe->inpos - 1);
310 }
311 
312 static int can_receive(void *opaque)
313 {
314     return 1;
315 }
316 
317 static void receive(void *opaque, const uint8_t *buf, int size)
318 {
319     IPMIBmcExtern *ibe = opaque;
320     int i;
321     unsigned char hw_op;
322 
323     for (i = 0; i < size; i++) {
324         unsigned char ch = buf[i];
325 
326         switch (ch) {
327         case VM_MSG_CHAR:
328             handle_msg(ibe);
329             ibe->in_too_many = false;
330             ibe->inpos = 0;
331             break;
332 
333         case VM_CMD_CHAR:
334             if (ibe->in_too_many) {
335                 ipmi_debug("cmd in too many\n");
336                 ibe->in_too_many = false;
337                 ibe->inpos = 0;
338                 break;
339             }
340             if (ibe->in_escape) {
341                 ipmi_debug("cmd in escape\n");
342                 ibe->in_too_many = false;
343                 ibe->inpos = 0;
344                 ibe->in_escape = false;
345                 break;
346             }
347             ibe->in_too_many = false;
348             if (ibe->inpos < 1) {
349                 break;
350             }
351             hw_op = ibe->inbuf[0];
352             ibe->inpos = 0;
353             goto out_hw_op;
354             break;
355 
356         case VM_ESCAPE_CHAR:
357             ibe->in_escape = true;
358             break;
359 
360         default:
361             if (ibe->in_escape) {
362                 ch &= ~0x10;
363                 ibe->in_escape = false;
364             }
365             if (ibe->in_too_many) {
366                 break;
367             }
368             if (ibe->inpos >= sizeof(ibe->inbuf)) {
369                 ibe->in_too_many = true;
370                 break;
371             }
372             ibe->inbuf[ibe->inpos] = ch;
373             ibe->inpos++;
374             break;
375         }
376     }
377     return;
378 
379  out_hw_op:
380     handle_hw_op(ibe, hw_op);
381 }
382 
383 static void chr_event(void *opaque, int event)
384 {
385     IPMIBmcExtern *ibe = opaque;
386     IPMIInterface *s = ibe->parent.intf;
387     IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
388     unsigned char v;
389 
390     switch (event) {
391     case CHR_EVENT_OPENED:
392         ibe->connected = true;
393         ibe->outpos = 0;
394         ibe->outlen = 0;
395         addchar(ibe, VM_CMD_VERSION);
396         addchar(ibe, VM_PROTOCOL_VERSION);
397         ibe->outbuf[ibe->outlen] = VM_CMD_CHAR;
398         ibe->outlen++;
399         addchar(ibe, VM_CMD_CAPABILITIES);
400         v = VM_CAPABILITIES_IRQ | VM_CAPABILITIES_ATTN;
401         if (k->do_hw_op(ibe->parent.intf, IPMI_POWEROFF_CHASSIS, 1) == 0) {
402             v |= VM_CAPABILITIES_POWER;
403         }
404         if (k->do_hw_op(ibe->parent.intf, IPMI_RESET_CHASSIS, 1) == 0) {
405             v |= VM_CAPABILITIES_RESET;
406         }
407         if (k->do_hw_op(ibe->parent.intf, IPMI_SEND_NMI, 1) == 0) {
408             v |= VM_CAPABILITIES_NMI;
409         }
410         addchar(ibe, v);
411         ibe->outbuf[ibe->outlen] = VM_CMD_CHAR;
412         ibe->outlen++;
413         ibe->sending_cmd = false;
414         continue_send(ibe);
415         break;
416 
417     case CHR_EVENT_CLOSED:
418         if (!ibe->connected) {
419             return;
420         }
421         ibe->connected = false;
422         if (ibe->waiting_rsp) {
423             ibe->waiting_rsp = false;
424             ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
425             ibe->inbuf[2] = ibe->outbuf[2];
426             ibe->inbuf[3] = IPMI_CC_BMC_INIT_IN_PROGRESS;
427             k->handle_rsp(s, ibe->outbuf[0], ibe->inbuf + 1, 3);
428         }
429         break;
430     }
431 }
432 
433 static void ipmi_bmc_extern_handle_reset(IPMIBmc *b)
434 {
435     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(b);
436 
437     ibe->send_reset = true;
438     continue_send(ibe);
439 }
440 
441 static void ipmi_bmc_extern_realize(DeviceState *dev, Error **errp)
442 {
443     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(dev);
444 
445     if (!qemu_chr_fe_get_driver(&ibe->chr)) {
446         error_setg(errp, "IPMI external bmc requires chardev attribute");
447         return;
448     }
449 
450     qemu_chr_fe_set_handlers(&ibe->chr, can_receive, receive,
451                              chr_event, ibe, NULL, true);
452 }
453 
454 static int ipmi_bmc_extern_post_migrate(void *opaque, int version_id)
455 {
456     IPMIBmcExtern *ibe = opaque;
457 
458     /*
459      * We don't directly restore waiting_rsp, Instead, we return an
460      * error on the interface if a response was being waited for.
461      */
462     if (ibe->waiting_rsp) {
463         IPMIInterface *ii = ibe->parent.intf;
464         IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
465 
466         ibe->waiting_rsp = false;
467         ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
468         ibe->inbuf[2] = ibe->outbuf[2];
469         ibe->inbuf[3] = IPMI_CC_BMC_INIT_IN_PROGRESS;
470         iic->handle_rsp(ii, ibe->outbuf[0], ibe->inbuf + 1, 3);
471     }
472     return 0;
473 }
474 
475 static const VMStateDescription vmstate_ipmi_bmc_extern = {
476     .name = TYPE_IPMI_BMC_EXTERN,
477     .version_id = 1,
478     .minimum_version_id = 1,
479     .post_load = ipmi_bmc_extern_post_migrate,
480     .fields      = (VMStateField[]) {
481         VMSTATE_BOOL(send_reset, IPMIBmcExtern),
482         VMSTATE_BOOL(waiting_rsp, IPMIBmcExtern),
483         VMSTATE_END_OF_LIST()
484     }
485 };
486 
487 static void ipmi_bmc_extern_init(Object *obj)
488 {
489     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(obj);
490 
491     ibe->extern_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, extern_timeout, ibe);
492     vmstate_register(NULL, 0, &vmstate_ipmi_bmc_extern, ibe);
493 }
494 
495 static void ipmi_bmc_extern_finalize(Object *obj)
496 {
497     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(obj);
498 
499     timer_del(ibe->extern_timer);
500     timer_free(ibe->extern_timer);
501 }
502 
503 static Property ipmi_bmc_extern_properties[] = {
504     DEFINE_PROP_CHR("chardev", IPMIBmcExtern, chr),
505     DEFINE_PROP_END_OF_LIST(),
506 };
507 
508 static void ipmi_bmc_extern_class_init(ObjectClass *oc, void *data)
509 {
510     DeviceClass *dc = DEVICE_CLASS(oc);
511     IPMIBmcClass *bk = IPMI_BMC_CLASS(oc);
512 
513     bk->handle_command = ipmi_bmc_extern_handle_command;
514     bk->handle_reset = ipmi_bmc_extern_handle_reset;
515     dc->realize = ipmi_bmc_extern_realize;
516     dc->props = ipmi_bmc_extern_properties;
517 }
518 
519 static const TypeInfo ipmi_bmc_extern_type = {
520     .name          = TYPE_IPMI_BMC_EXTERN,
521     .parent        = TYPE_IPMI_BMC,
522     .instance_size = sizeof(IPMIBmcExtern),
523     .instance_init = ipmi_bmc_extern_init,
524     .instance_finalize = ipmi_bmc_extern_finalize,
525     .class_init    = ipmi_bmc_extern_class_init,
526  };
527 
528 static void ipmi_bmc_extern_register_types(void)
529 {
530     type_register_static(&ipmi_bmc_extern_type);
531 }
532 
533 type_init(ipmi_bmc_extern_register_types)
534