xref: /openbmc/qemu/hw/ipmi/smbus_ipmi.c (revision effd60c8)
1 /*
2  * QEMU IPMI SMBus (SSIF) emulation
3  *
4  * Copyright (c) 2015,2016 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 #include "qemu/osdep.h"
25 #include "migration/vmstate.h"
26 #include "hw/i2c/smbus_slave.h"
27 #include "qapi/error.h"
28 #include "qemu/error-report.h"
29 #include "hw/ipmi/ipmi.h"
30 #include "qom/object.h"
31 #include "hw/acpi/ipmi.h"
32 
33 #define TYPE_SMBUS_IPMI "smbus-ipmi"
34 OBJECT_DECLARE_SIMPLE_TYPE(SMBusIPMIDevice, SMBUS_IPMI)
35 
36 #define SSIF_IPMI_REQUEST                       2
37 #define SSIF_IPMI_MULTI_PART_REQUEST_START      6
38 #define SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE     7
39 #define SSIF_IPMI_MULTI_PART_REQUEST_END        8
40 #define SSIF_IPMI_RESPONSE                      3
41 #define SSIF_IPMI_MULTI_PART_RESPONSE_MIDDLE    9
42 #define SSIF_IPMI_MULTI_PART_RETRY              0xa
43 
44 #define MAX_SSIF_IPMI_MSG_SIZE 255
45 #define MAX_SSIF_IPMI_MSG_CHUNK 32
46 
47 #define IPMI_GET_SYS_INTF_CAP_CMD 0x57
48 
49 struct SMBusIPMIDevice {
50     SMBusDevice parent;
51 
52     IPMIBmc *bmc;
53 
54     uint8_t outmsg[MAX_SSIF_IPMI_MSG_SIZE];
55     uint32_t outlen;
56     uint32_t currblk;
57 
58     /* Holds the SMBUS message currently being sent to the host. */
59     uint8_t outbuf[MAX_SSIF_IPMI_MSG_CHUNK + 1]; /* len + message. */
60     uint32_t outpos;
61 
62     uint8_t inmsg[MAX_SSIF_IPMI_MSG_SIZE];
63     uint32_t inlen;
64 
65     /*
66      * This is a response number that we send with the command to make
67      * sure that the response matches the command.
68      */
69     uint8_t waiting_rsp;
70 
71     uint32_t uuid;
72 };
73 
74 static void smbus_ipmi_handle_event(IPMIInterface *ii)
75 {
76     /* No interrupts, so nothing to do here. */
77 }
78 
79 static void smbus_ipmi_handle_rsp(IPMIInterface *ii, uint8_t msg_id,
80                                   unsigned char *rsp, unsigned int rsp_len)
81 {
82     SMBusIPMIDevice *sid = SMBUS_IPMI(ii);
83 
84     if (sid->waiting_rsp == msg_id) {
85         sid->waiting_rsp++;
86 
87         if (rsp_len > MAX_SSIF_IPMI_MSG_SIZE) {
88             rsp[2] = IPMI_CC_REQUEST_DATA_TRUNCATED;
89             rsp_len = MAX_SSIF_IPMI_MSG_SIZE;
90         }
91         memcpy(sid->outmsg, rsp, rsp_len);
92         sid->outlen = rsp_len;
93         sid->outpos = 0;
94         sid->currblk = 0;
95     }
96 }
97 
98 static void smbus_ipmi_set_atn(IPMIInterface *ii, int val, int irq)
99 {
100     /* This is where PEC would go. */
101 }
102 
103 static void smbus_ipmi_set_irq_enable(IPMIInterface *ii, int val)
104 {
105 }
106 
107 static void smbus_ipmi_send_msg(SMBusIPMIDevice *sid)
108 {
109     uint8_t *msg = sid->inmsg;
110     uint32_t len = sid->inlen;
111     IPMIBmcClass *bk = IPMI_BMC_GET_CLASS(sid->bmc);
112 
113     sid->outlen = 0;
114     sid->outpos = 0;
115     sid->currblk = 0;
116 
117     if (msg[0] == (IPMI_NETFN_APP << 2) && msg[1] == IPMI_GET_SYS_INTF_CAP_CMD)
118     {
119         /* We handle this ourself. */
120         sid->outmsg[0] = (IPMI_NETFN_APP + 1) << 2;
121         sid->outmsg[1] = msg[1];
122         if (len < 3) {
123             sid->outmsg[2] = IPMI_CC_REQUEST_DATA_LENGTH_INVALID;
124             sid->outlen = 3;
125         } else if ((msg[2] & 0x0f) != 0) {
126             sid->outmsg[2] = IPMI_CC_INVALID_DATA_FIELD;
127             sid->outlen = 3;
128         } else {
129             sid->outmsg[2] = 0;
130             sid->outmsg[3] = 0;
131             sid->outmsg[4] = (2 << 6); /* Multi-part supported. */
132             sid->outmsg[5] = MAX_SSIF_IPMI_MSG_SIZE;
133             sid->outmsg[6] = MAX_SSIF_IPMI_MSG_SIZE;
134             sid->outlen = 7;
135         }
136         return;
137     }
138 
139     bk->handle_command(sid->bmc, sid->inmsg, sid->inlen, sizeof(sid->inmsg),
140                        sid->waiting_rsp);
141 }
142 
143 static uint8_t ipmi_receive_byte(SMBusDevice *dev)
144 {
145     SMBusIPMIDevice *sid = SMBUS_IPMI(dev);
146 
147     if (sid->outpos >= sizeof(sid->outbuf)) {
148         return 0xff;
149     }
150 
151     return sid->outbuf[sid->outpos++];
152 }
153 
154 static int ipmi_load_readbuf(SMBusIPMIDevice *sid)
155 {
156     unsigned int block = sid->currblk, pos, len;
157 
158     if (sid->outlen == 0) {
159         return -1;
160     }
161 
162     if (sid->outlen <= 32) {
163         if (block != 0) {
164             return -1;
165         }
166         sid->outbuf[0] = sid->outlen;
167         memcpy(sid->outbuf + 1, sid->outmsg, sid->outlen);
168         sid->outpos = 0;
169         return 0;
170     }
171 
172     if (block == 0) {
173         sid->outbuf[0] = 32;
174         sid->outbuf[1] = 0;
175         sid->outbuf[2] = 1;
176         memcpy(sid->outbuf + 3, sid->outmsg, 30);
177         sid->outpos = 0;
178         return 0;
179     }
180 
181     /*
182      * Calculate the position in outmsg.  30 for the first block, 31
183      * for the rest of the blocks.
184      */
185     pos = 30 + (block - 1) * 31;
186 
187     if (pos >= sid->outlen) {
188         return -1;
189     }
190 
191     len = sid->outlen - pos;
192     if (len > 31) {
193         /* More chunks after this. */
194         len = 31;
195         /* Blocks start at 0 for the first middle transaction. */
196         sid->outbuf[1] = block - 1;
197     } else {
198         sid->outbuf[1] = 0xff; /* End of message marker. */
199     }
200 
201     sid->outbuf[0] = len + 1;
202     memcpy(sid->outbuf + 2, sid->outmsg + pos, len);
203     sid->outpos = 0;
204     return 0;
205 }
206 
207 static int ipmi_write_data(SMBusDevice *dev, uint8_t *buf, uint8_t len)
208 {
209     SMBusIPMIDevice *sid = SMBUS_IPMI(dev);
210     bool send = false;
211     uint8_t cmd;
212     int ret = 0;
213 
214     /* length is guaranteed to be >= 1. */
215     cmd = *buf++;
216     len--;
217 
218     /* Handle read request, which don't have any data in the write part. */
219     switch (cmd) {
220     case SSIF_IPMI_RESPONSE:
221         sid->currblk = 0;
222         ret = ipmi_load_readbuf(sid);
223         break;
224 
225     case SSIF_IPMI_MULTI_PART_RESPONSE_MIDDLE:
226         sid->currblk++;
227         ret = ipmi_load_readbuf(sid);
228         break;
229 
230     case SSIF_IPMI_MULTI_PART_RETRY:
231         if (len >= 1) {
232             sid->currblk = buf[0];
233             ret = ipmi_load_readbuf(sid);
234         } else {
235             ret = -1;
236         }
237         break;
238 
239     default:
240         break;
241     }
242 
243     /* This should be a message write, make the length is there and correct. */
244     if (len >= 1) {
245         if (*buf != len - 1 || *buf > MAX_SSIF_IPMI_MSG_CHUNK) {
246             return -1; /* Bogus message */
247         }
248         buf++;
249         len--;
250     }
251 
252     switch (cmd) {
253     case SSIF_IPMI_REQUEST:
254         send = true;
255         /* FALLTHRU */
256     case SSIF_IPMI_MULTI_PART_REQUEST_START:
257         if (len < 2) {
258             return -1; /* Bogus. */
259         }
260         memcpy(sid->inmsg, buf, len);
261         sid->inlen = len;
262         break;
263 
264     case SSIF_IPMI_MULTI_PART_REQUEST_END:
265         send = true;
266         /* FALLTHRU */
267     case SSIF_IPMI_MULTI_PART_REQUEST_MIDDLE:
268         if (!sid->inlen) {
269             return -1; /* Bogus. */
270         }
271         if (sid->inlen + len > MAX_SSIF_IPMI_MSG_SIZE) {
272             sid->inlen = 0; /* Discard the message. */
273             return -1; /* Bogus. */
274         }
275         if (len < 32) {
276             /*
277              * Special hack, a multi-part middle that is less than 32 bytes
278              * marks the end of a message.  The specification is fairly
279              * confusing, so some systems to this, even sending a zero
280              * length end message to mark the end.
281              */
282             send = true;
283         }
284         if (len > 0) {
285             memcpy(sid->inmsg + sid->inlen, buf, len);
286         }
287         sid->inlen += len;
288         break;
289     }
290 
291     if (send && sid->inlen) {
292         smbus_ipmi_send_msg(sid);
293     }
294 
295     return ret;
296 }
297 
298 static const VMStateDescription vmstate_smbus_ipmi = {
299     .name = TYPE_SMBUS_IPMI,
300     .version_id = 1,
301     .minimum_version_id = 1,
302     .fields = (const VMStateField[]) {
303         VMSTATE_SMBUS_DEVICE(parent, SMBusIPMIDevice),
304         VMSTATE_UINT8(waiting_rsp, SMBusIPMIDevice),
305         VMSTATE_UINT32(outlen, SMBusIPMIDevice),
306         VMSTATE_UINT32(currblk, SMBusIPMIDevice),
307         VMSTATE_UINT8_ARRAY(outmsg, SMBusIPMIDevice, MAX_SSIF_IPMI_MSG_SIZE),
308         VMSTATE_UINT32(outpos, SMBusIPMIDevice),
309         VMSTATE_UINT8_ARRAY(outbuf, SMBusIPMIDevice,
310                             MAX_SSIF_IPMI_MSG_CHUNK + 1),
311         VMSTATE_UINT32(inlen, SMBusIPMIDevice),
312         VMSTATE_UINT8_ARRAY(inmsg, SMBusIPMIDevice, MAX_SSIF_IPMI_MSG_SIZE),
313         VMSTATE_END_OF_LIST()
314     }
315 };
316 
317 static void smbus_ipmi_realize(DeviceState *dev, Error **errp)
318 {
319     SMBusIPMIDevice *sid = SMBUS_IPMI(dev);
320     IPMIInterface *ii = IPMI_INTERFACE(dev);
321 
322     if (!sid->bmc) {
323         error_setg(errp, "IPMI device requires a bmc attribute to be set");
324         return;
325     }
326 
327     sid->uuid = ipmi_next_uuid();
328 
329     sid->bmc->intf = ii;
330 }
331 
332 static void smbus_ipmi_init(Object *obj)
333 {
334     SMBusIPMIDevice *sid = SMBUS_IPMI(obj);
335 
336     ipmi_bmc_find_and_link(obj, (Object **) &sid->bmc);
337 }
338 
339 static void smbus_ipmi_get_fwinfo(struct IPMIInterface *ii, IPMIFwInfo *info)
340 {
341     SMBusIPMIDevice *sid = SMBUS_IPMI(ii);
342 
343     info->interface_name = "smbus";
344     info->interface_type = IPMI_SMBIOS_SSIF;
345     info->ipmi_spec_major_revision = 2;
346     info->ipmi_spec_minor_revision = 0;
347     info->i2c_slave_address = sid->bmc->slave_addr;
348     info->base_address = sid->parent.i2c.address;
349     info->memspace = IPMI_MEMSPACE_SMBUS;
350     info->register_spacing = 1;
351     info->uuid = sid->uuid;
352 }
353 
354 static void smbus_ipmi_class_init(ObjectClass *oc, void *data)
355 {
356     DeviceClass *dc = DEVICE_CLASS(oc);
357     IPMIInterfaceClass *iic = IPMI_INTERFACE_CLASS(oc);
358     SMBusDeviceClass *sc = SMBUS_DEVICE_CLASS(oc);
359     AcpiDevAmlIfClass *adevc = ACPI_DEV_AML_IF_CLASS(oc);
360 
361     sc->receive_byte = ipmi_receive_byte;
362     sc->write_data = ipmi_write_data;
363     dc->vmsd = &vmstate_smbus_ipmi;
364     dc->realize = smbus_ipmi_realize;
365     iic->set_atn = smbus_ipmi_set_atn;
366     iic->handle_rsp = smbus_ipmi_handle_rsp;
367     iic->handle_if_event = smbus_ipmi_handle_event;
368     iic->set_irq_enable = smbus_ipmi_set_irq_enable;
369     iic->get_fwinfo = smbus_ipmi_get_fwinfo;
370     adevc->build_dev_aml = build_ipmi_dev_aml;
371 }
372 
373 static const TypeInfo smbus_ipmi_info = {
374     .name          = TYPE_SMBUS_IPMI,
375     .parent        = TYPE_SMBUS_DEVICE,
376     .instance_size = sizeof(SMBusIPMIDevice),
377     .instance_init = smbus_ipmi_init,
378     .class_init    = smbus_ipmi_class_init,
379     .interfaces = (InterfaceInfo[]) {
380         { TYPE_IPMI_INTERFACE },
381         { TYPE_ACPI_DEV_AML_IF },
382         { }
383     }
384 };
385 
386 static void smbus_ipmi_register_types(void)
387 {
388     type_register_static(&smbus_ipmi_info);
389 }
390 
391 type_init(smbus_ipmi_register_types)
392