xref: /openbmc/qemu/hw/ipmi/ipmi_bmc_extern.c (revision 3d9569b8)
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 "qemu/error-report.h"
32 #include "qemu/module.h"
33 #include "qapi/error.h"
34 #include "qemu/timer.h"
35 #include "chardev/char-fe.h"
36 #include "sysemu/sysemu.h"
37 #include "hw/ipmi/ipmi.h"
38 
39 #define VM_MSG_CHAR        0xA0 /* Marks end of message */
40 #define VM_CMD_CHAR        0xA1 /* Marks end of a command */
41 #define VM_ESCAPE_CHAR     0xAA /* Set bit 4 from the next byte to 0 */
42 
43 #define VM_PROTOCOL_VERSION        1
44 #define VM_CMD_VERSION             0xff /* A version number byte follows */
45 #define VM_CMD_NOATTN              0x00
46 #define VM_CMD_ATTN                0x01
47 #define VM_CMD_ATTN_IRQ            0x02
48 #define VM_CMD_POWEROFF            0x03
49 #define VM_CMD_RESET               0x04
50 #define VM_CMD_ENABLE_IRQ          0x05 /* Enable/disable the messaging irq */
51 #define VM_CMD_DISABLE_IRQ         0x06
52 #define VM_CMD_SEND_NMI            0x07
53 #define VM_CMD_CAPABILITIES        0x08
54 #define   VM_CAPABILITIES_POWER    0x01
55 #define   VM_CAPABILITIES_RESET    0x02
56 #define   VM_CAPABILITIES_IRQ      0x04
57 #define   VM_CAPABILITIES_NMI      0x08
58 #define   VM_CAPABILITIES_ATTN     0x10
59 #define   VM_CAPABILITIES_GRACEFUL_SHUTDOWN 0x20
60 #define VM_CMD_GRACEFUL_SHUTDOWN   0x09
61 
62 #define TYPE_IPMI_BMC_EXTERN "ipmi-bmc-extern"
63 #define IPMI_BMC_EXTERN(obj) OBJECT_CHECK(IPMIBmcExtern, (obj), \
64                                         TYPE_IPMI_BMC_EXTERN)
65 typedef struct IPMIBmcExtern {
66     IPMIBmc parent;
67 
68     CharBackend chr;
69 
70     bool connected;
71 
72     unsigned char inbuf[MAX_IPMI_MSG_SIZE + 2];
73     unsigned int inpos;
74     bool in_escape;
75     bool in_too_many;
76     bool waiting_rsp;
77     bool sending_cmd;
78 
79     unsigned char outbuf[(MAX_IPMI_MSG_SIZE + 2) * 2 + 1];
80     unsigned int outpos;
81     unsigned int outlen;
82 
83     struct QEMUTimer *extern_timer;
84 
85     /* A reset event is pending to be sent upstream. */
86     bool send_reset;
87 } IPMIBmcExtern;
88 
89 static int can_receive(void *opaque);
90 static void receive(void *opaque, const uint8_t *buf, int size);
91 static void chr_event(void *opaque, int event);
92 
93 static unsigned char
94 ipmb_checksum(const unsigned char *data, int size, unsigned char start)
95 {
96         unsigned char csum = start;
97 
98         for (; size > 0; size--, data++) {
99                 csum += *data;
100         }
101         return csum;
102 }
103 
104 static void continue_send(IPMIBmcExtern *ibe)
105 {
106     int ret;
107     if (ibe->outlen == 0) {
108         goto check_reset;
109     }
110  send:
111     ret = qemu_chr_fe_write(&ibe->chr, ibe->outbuf + ibe->outpos,
112                             ibe->outlen - ibe->outpos);
113     if (ret > 0) {
114         ibe->outpos += ret;
115     }
116     if (ibe->outpos < ibe->outlen) {
117         /* Not fully transmitted, try again in a 10ms */
118         timer_mod_ns(ibe->extern_timer,
119                      qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 10000000);
120     } else {
121         /* Sent */
122         ibe->outlen = 0;
123         ibe->outpos = 0;
124         if (!ibe->sending_cmd) {
125             ibe->waiting_rsp = true;
126         } else {
127             ibe->sending_cmd = false;
128         }
129     check_reset:
130         if (ibe->connected && ibe->send_reset) {
131             /* Send the reset */
132             ibe->outbuf[0] = VM_CMD_RESET;
133             ibe->outbuf[1] = VM_CMD_CHAR;
134             ibe->outlen = 2;
135             ibe->outpos = 0;
136             ibe->send_reset = false;
137             ibe->sending_cmd = true;
138             goto send;
139         }
140 
141         if (ibe->waiting_rsp) {
142             /* Make sure we get a response within 4 seconds. */
143             timer_mod_ns(ibe->extern_timer,
144                          qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) + 4000000000ULL);
145         }
146     }
147     return;
148 }
149 
150 static void extern_timeout(void *opaque)
151 {
152     IPMIBmcExtern *ibe = opaque;
153     IPMIInterface *s = ibe->parent.intf;
154 
155     if (ibe->connected) {
156         if (ibe->waiting_rsp && (ibe->outlen == 0)) {
157             IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
158             /* The message response timed out, return an error. */
159             ibe->waiting_rsp = false;
160             ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
161             ibe->inbuf[2] = ibe->outbuf[2];
162             ibe->inbuf[3] = IPMI_CC_TIMEOUT;
163             k->handle_rsp(s, ibe->outbuf[0], ibe->inbuf + 1, 3);
164         } else {
165             continue_send(ibe);
166         }
167     }
168 }
169 
170 static void addchar(IPMIBmcExtern *ibe, unsigned char ch)
171 {
172     switch (ch) {
173     case VM_MSG_CHAR:
174     case VM_CMD_CHAR:
175     case VM_ESCAPE_CHAR:
176         ibe->outbuf[ibe->outlen] = VM_ESCAPE_CHAR;
177         ibe->outlen++;
178         ch |= 0x10;
179         /* No break */
180 
181     default:
182         ibe->outbuf[ibe->outlen] = ch;
183         ibe->outlen++;
184     }
185 }
186 
187 static void ipmi_bmc_extern_handle_command(IPMIBmc *b,
188                                        uint8_t *cmd, unsigned int cmd_len,
189                                        unsigned int max_cmd_len,
190                                        uint8_t msg_id)
191 {
192     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(b);
193     IPMIInterface *s = ibe->parent.intf;
194     uint8_t err = 0, csum;
195     unsigned int i;
196 
197     if (ibe->outlen) {
198         /* We already have a command queued.  Shouldn't ever happen. */
199         error_report("IPMI KCS: Got command when not finished with the"
200                      " previous command");
201         abort();
202     }
203 
204     /* If it's too short or it was truncated, return an error. */
205     if (cmd_len < 2) {
206         err = IPMI_CC_REQUEST_DATA_LENGTH_INVALID;
207     } else if ((cmd_len > max_cmd_len) || (cmd_len > MAX_IPMI_MSG_SIZE)) {
208         err = IPMI_CC_REQUEST_DATA_TRUNCATED;
209     } else if (!ibe->connected) {
210         err = IPMI_CC_BMC_INIT_IN_PROGRESS;
211     }
212     if (err) {
213         IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
214         unsigned char rsp[3];
215         rsp[0] = cmd[0] | 0x04;
216         rsp[1] = cmd[1];
217         rsp[2] = err;
218         ibe->waiting_rsp = false;
219         k->handle_rsp(s, msg_id, rsp, 3);
220         goto out;
221     }
222 
223     addchar(ibe, msg_id);
224     for (i = 0; i < cmd_len; i++) {
225         addchar(ibe, cmd[i]);
226     }
227     csum = ipmb_checksum(&msg_id, 1, 0);
228     addchar(ibe, -ipmb_checksum(cmd, cmd_len, csum));
229 
230     ibe->outbuf[ibe->outlen] = VM_MSG_CHAR;
231     ibe->outlen++;
232 
233     /* Start the transmit */
234     continue_send(ibe);
235 
236  out:
237     return;
238 }
239 
240 static void handle_hw_op(IPMIBmcExtern *ibe, unsigned char hw_op)
241 {
242     IPMIInterface *s = ibe->parent.intf;
243     IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
244 
245     switch (hw_op) {
246     case VM_CMD_VERSION:
247         /* We only support one version at this time. */
248         break;
249 
250     case VM_CMD_NOATTN:
251         k->set_atn(s, 0, 0);
252         break;
253 
254     case VM_CMD_ATTN:
255         k->set_atn(s, 1, 0);
256         break;
257 
258     case VM_CMD_ATTN_IRQ:
259         k->set_atn(s, 1, 1);
260         break;
261 
262     case VM_CMD_POWEROFF:
263         k->do_hw_op(s, IPMI_POWEROFF_CHASSIS, 0);
264         break;
265 
266     case VM_CMD_RESET:
267         k->do_hw_op(s, IPMI_RESET_CHASSIS, 0);
268         break;
269 
270     case VM_CMD_ENABLE_IRQ:
271         k->set_irq_enable(s, 1);
272         break;
273 
274     case VM_CMD_DISABLE_IRQ:
275         k->set_irq_enable(s, 0);
276         break;
277 
278     case VM_CMD_SEND_NMI:
279         k->do_hw_op(s, IPMI_SEND_NMI, 0);
280         break;
281 
282     case VM_CMD_GRACEFUL_SHUTDOWN:
283         k->do_hw_op(s, IPMI_SHUTDOWN_VIA_ACPI_OVERTEMP, 0);
284         break;
285     }
286 }
287 
288 static void handle_msg(IPMIBmcExtern *ibe)
289 {
290     IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(ibe->parent.intf);
291 
292     if (ibe->in_escape) {
293         ipmi_debug("msg escape not ended\n");
294         return;
295     }
296     if (ibe->inpos < 5) {
297         ipmi_debug("msg too short\n");
298         return;
299     }
300     if (ibe->in_too_many) {
301         ibe->inbuf[3] = IPMI_CC_REQUEST_DATA_TRUNCATED;
302         ibe->inpos = 4;
303     } else if (ipmb_checksum(ibe->inbuf, ibe->inpos, 0) != 0) {
304         ipmi_debug("msg checksum failure\n");
305         return;
306     } else {
307         ibe->inpos--; /* Remove checkum */
308     }
309 
310     timer_del(ibe->extern_timer);
311     ibe->waiting_rsp = false;
312     k->handle_rsp(ibe->parent.intf, ibe->inbuf[0], ibe->inbuf + 1, ibe->inpos - 1);
313 }
314 
315 static int can_receive(void *opaque)
316 {
317     return 1;
318 }
319 
320 static void receive(void *opaque, const uint8_t *buf, int size)
321 {
322     IPMIBmcExtern *ibe = opaque;
323     int i;
324     unsigned char hw_op;
325 
326     for (i = 0; i < size; i++) {
327         unsigned char ch = buf[i];
328 
329         switch (ch) {
330         case VM_MSG_CHAR:
331             handle_msg(ibe);
332             ibe->in_too_many = false;
333             ibe->inpos = 0;
334             break;
335 
336         case VM_CMD_CHAR:
337             if (ibe->in_too_many) {
338                 ipmi_debug("cmd in too many\n");
339                 ibe->in_too_many = false;
340                 ibe->inpos = 0;
341                 break;
342             }
343             if (ibe->in_escape) {
344                 ipmi_debug("cmd in escape\n");
345                 ibe->in_too_many = false;
346                 ibe->inpos = 0;
347                 ibe->in_escape = false;
348                 break;
349             }
350             ibe->in_too_many = false;
351             if (ibe->inpos < 1) {
352                 break;
353             }
354             hw_op = ibe->inbuf[0];
355             ibe->inpos = 0;
356             goto out_hw_op;
357             break;
358 
359         case VM_ESCAPE_CHAR:
360             ibe->in_escape = true;
361             break;
362 
363         default:
364             if (ibe->in_escape) {
365                 ch &= ~0x10;
366                 ibe->in_escape = false;
367             }
368             if (ibe->in_too_many) {
369                 break;
370             }
371             if (ibe->inpos >= sizeof(ibe->inbuf)) {
372                 ibe->in_too_many = true;
373                 break;
374             }
375             ibe->inbuf[ibe->inpos] = ch;
376             ibe->inpos++;
377             break;
378         }
379     }
380     return;
381 
382  out_hw_op:
383     handle_hw_op(ibe, hw_op);
384 }
385 
386 static void chr_event(void *opaque, int event)
387 {
388     IPMIBmcExtern *ibe = opaque;
389     IPMIInterface *s = ibe->parent.intf;
390     IPMIInterfaceClass *k = IPMI_INTERFACE_GET_CLASS(s);
391     unsigned char v;
392 
393     switch (event) {
394     case CHR_EVENT_OPENED:
395         ibe->connected = true;
396         ibe->outpos = 0;
397         ibe->outlen = 0;
398         addchar(ibe, VM_CMD_VERSION);
399         addchar(ibe, VM_PROTOCOL_VERSION);
400         ibe->outbuf[ibe->outlen] = VM_CMD_CHAR;
401         ibe->outlen++;
402         addchar(ibe, VM_CMD_CAPABILITIES);
403         v = VM_CAPABILITIES_IRQ | VM_CAPABILITIES_ATTN;
404         if (k->do_hw_op(ibe->parent.intf, IPMI_POWEROFF_CHASSIS, 1) == 0) {
405             v |= VM_CAPABILITIES_POWER;
406         }
407         if (k->do_hw_op(ibe->parent.intf, IPMI_SHUTDOWN_VIA_ACPI_OVERTEMP, 1)
408             == 0) {
409             v |= VM_CAPABILITIES_GRACEFUL_SHUTDOWN;
410         }
411         if (k->do_hw_op(ibe->parent.intf, IPMI_RESET_CHASSIS, 1) == 0) {
412             v |= VM_CAPABILITIES_RESET;
413         }
414         if (k->do_hw_op(ibe->parent.intf, IPMI_SEND_NMI, 1) == 0) {
415             v |= VM_CAPABILITIES_NMI;
416         }
417         addchar(ibe, v);
418         ibe->outbuf[ibe->outlen] = VM_CMD_CHAR;
419         ibe->outlen++;
420         ibe->sending_cmd = false;
421         continue_send(ibe);
422         break;
423 
424     case CHR_EVENT_CLOSED:
425         if (!ibe->connected) {
426             return;
427         }
428         ibe->connected = false;
429         /*
430          * Don't hang the OS trying to handle the ATN bit, other end will
431          * resend on a reconnect.
432          */
433         k->set_atn(s, 0, 0);
434         if (ibe->waiting_rsp) {
435             ibe->waiting_rsp = false;
436             ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
437             ibe->inbuf[2] = ibe->outbuf[2];
438             ibe->inbuf[3] = IPMI_CC_BMC_INIT_IN_PROGRESS;
439             k->handle_rsp(s, ibe->outbuf[0], ibe->inbuf + 1, 3);
440         }
441         break;
442     }
443 }
444 
445 static void ipmi_bmc_extern_handle_reset(IPMIBmc *b)
446 {
447     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(b);
448 
449     ibe->send_reset = true;
450     continue_send(ibe);
451 }
452 
453 static void ipmi_bmc_extern_realize(DeviceState *dev, Error **errp)
454 {
455     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(dev);
456 
457     if (!qemu_chr_fe_backend_connected(&ibe->chr)) {
458         error_setg(errp, "IPMI external bmc requires chardev attribute");
459         return;
460     }
461 
462     qemu_chr_fe_set_handlers(&ibe->chr, can_receive, receive,
463                              chr_event, NULL, ibe, NULL, true);
464 }
465 
466 static int ipmi_bmc_extern_post_migrate(void *opaque, int version_id)
467 {
468     IPMIBmcExtern *ibe = opaque;
469 
470     /*
471      * We don't directly restore waiting_rsp, Instead, we return an
472      * error on the interface if a response was being waited for.
473      */
474     if (ibe->waiting_rsp) {
475         IPMIInterface *ii = ibe->parent.intf;
476         IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
477 
478         ibe->waiting_rsp = false;
479         ibe->inbuf[1] = ibe->outbuf[1] | 0x04;
480         ibe->inbuf[2] = ibe->outbuf[2];
481         ibe->inbuf[3] = IPMI_CC_BMC_INIT_IN_PROGRESS;
482         iic->handle_rsp(ii, ibe->outbuf[0], ibe->inbuf + 1, 3);
483     }
484     return 0;
485 }
486 
487 static const VMStateDescription vmstate_ipmi_bmc_extern = {
488     .name = TYPE_IPMI_BMC_EXTERN,
489     .version_id = 1,
490     .minimum_version_id = 1,
491     .post_load = ipmi_bmc_extern_post_migrate,
492     .fields      = (VMStateField[]) {
493         VMSTATE_BOOL(send_reset, IPMIBmcExtern),
494         VMSTATE_BOOL(waiting_rsp, IPMIBmcExtern),
495         VMSTATE_END_OF_LIST()
496     }
497 };
498 
499 static void ipmi_bmc_extern_init(Object *obj)
500 {
501     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(obj);
502 
503     ibe->extern_timer = timer_new_ns(QEMU_CLOCK_VIRTUAL, extern_timeout, ibe);
504     vmstate_register(NULL, 0, &vmstate_ipmi_bmc_extern, ibe);
505 }
506 
507 static void ipmi_bmc_extern_finalize(Object *obj)
508 {
509     IPMIBmcExtern *ibe = IPMI_BMC_EXTERN(obj);
510 
511     timer_del(ibe->extern_timer);
512     timer_free(ibe->extern_timer);
513 }
514 
515 static Property ipmi_bmc_extern_properties[] = {
516     DEFINE_PROP_CHR("chardev", IPMIBmcExtern, chr),
517     DEFINE_PROP_END_OF_LIST(),
518 };
519 
520 static void ipmi_bmc_extern_class_init(ObjectClass *oc, void *data)
521 {
522     DeviceClass *dc = DEVICE_CLASS(oc);
523     IPMIBmcClass *bk = IPMI_BMC_CLASS(oc);
524 
525     bk->handle_command = ipmi_bmc_extern_handle_command;
526     bk->handle_reset = ipmi_bmc_extern_handle_reset;
527     dc->hotpluggable = false;
528     dc->realize = ipmi_bmc_extern_realize;
529     dc->props = ipmi_bmc_extern_properties;
530 }
531 
532 static const TypeInfo ipmi_bmc_extern_type = {
533     .name          = TYPE_IPMI_BMC_EXTERN,
534     .parent        = TYPE_IPMI_BMC,
535     .instance_size = sizeof(IPMIBmcExtern),
536     .instance_init = ipmi_bmc_extern_init,
537     .instance_finalize = ipmi_bmc_extern_finalize,
538     .class_init    = ipmi_bmc_extern_class_init,
539  };
540 
541 static void ipmi_bmc_extern_register_types(void)
542 {
543     type_register_static(&ipmi_bmc_extern_type);
544 }
545 
546 type_init(ipmi_bmc_extern_register_types)
547