xref: /openbmc/qemu/hw/ipmi/ipmi_kcs.c (revision efb91426)
1 /*
2  * QEMU IPMI KCS emulation
3  *
4  * Copyright (c) 2015,2017 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 "qemu/log.h"
27 #include "qapi/error.h"
28 #include "hw/ipmi/ipmi_kcs.h"
29 
30 #define IPMI_KCS_OBF_BIT        0
31 #define IPMI_KCS_IBF_BIT        1
32 #define IPMI_KCS_SMS_ATN_BIT    2
33 #define IPMI_KCS_CD_BIT         3
34 
35 #define IPMI_KCS_OBF_MASK          (1 << IPMI_KCS_OBF_BIT)
36 #define IPMI_KCS_GET_OBF(d)        (((d) >> IPMI_KCS_OBF_BIT) & 0x1)
37 #define IPMI_KCS_SET_OBF(d, v)     (d) = (((d) & ~IPMI_KCS_OBF_MASK) | \
38                                        (((v) & 1) << IPMI_KCS_OBF_BIT))
39 #define IPMI_KCS_IBF_MASK          (1 << IPMI_KCS_IBF_BIT)
40 #define IPMI_KCS_GET_IBF(d)        (((d) >> IPMI_KCS_IBF_BIT) & 0x1)
41 #define IPMI_KCS_SET_IBF(d, v)     (d) = (((d) & ~IPMI_KCS_IBF_MASK) | \
42                                        (((v) & 1) << IPMI_KCS_IBF_BIT))
43 #define IPMI_KCS_SMS_ATN_MASK      (1 << IPMI_KCS_SMS_ATN_BIT)
44 #define IPMI_KCS_GET_SMS_ATN(d)    (((d) >> IPMI_KCS_SMS_ATN_BIT) & 0x1)
45 #define IPMI_KCS_SET_SMS_ATN(d, v) (d) = (((d) & ~IPMI_KCS_SMS_ATN_MASK) | \
46                                        (((v) & 1) << IPMI_KCS_SMS_ATN_BIT))
47 #define IPMI_KCS_CD_MASK           (1 << IPMI_KCS_CD_BIT)
48 #define IPMI_KCS_GET_CD(d)         (((d) >> IPMI_KCS_CD_BIT) & 0x1)
49 #define IPMI_KCS_SET_CD(d, v)      (d) = (((d) & ~IPMI_KCS_CD_MASK) | \
50                                        (((v) & 1) << IPMI_KCS_CD_BIT))
51 
52 #define IPMI_KCS_IDLE_STATE        0
53 #define IPMI_KCS_READ_STATE        1
54 #define IPMI_KCS_WRITE_STATE       2
55 #define IPMI_KCS_ERROR_STATE       3
56 
57 #define IPMI_KCS_GET_STATE(d)    (((d) >> 6) & 0x3)
58 #define IPMI_KCS_SET_STATE(d, v) ((d) = ((d) & ~0xc0) | (((v) & 0x3) << 6))
59 
60 #define IPMI_KCS_ABORT_STATUS_CMD       0x60
61 #define IPMI_KCS_WRITE_START_CMD        0x61
62 #define IPMI_KCS_WRITE_END_CMD          0x62
63 #define IPMI_KCS_READ_CMD               0x68
64 
65 #define IPMI_KCS_STATUS_NO_ERR          0x00
66 #define IPMI_KCS_STATUS_ABORTED_ERR     0x01
67 #define IPMI_KCS_STATUS_BAD_CC_ERR      0x02
68 #define IPMI_KCS_STATUS_LENGTH_ERR      0x06
69 
70 static void ipmi_kcs_raise_irq(IPMIKCS *ik)
71 {
72     if (ik->use_irq && ik->irqs_enabled && ik->raise_irq) {
73         ik->raise_irq(ik);
74     }
75 }
76 
77 static void ipmi_kcs_lower_irq(IPMIKCS *ik)
78 {
79     if (ik->lower_irq) {
80         ik->lower_irq(ik);
81     }
82 }
83 
84 #define SET_OBF() \
85     do {                                                                      \
86         IPMI_KCS_SET_OBF(ik->status_reg, 1);                                  \
87         if (!ik->obf_irq_set) {                                               \
88             ik->obf_irq_set = 1;                                              \
89             if (!ik->atn_irq_set) {                                           \
90                 ipmi_kcs_raise_irq(ik);                                  \
91             }                                                                 \
92         }                                                                     \
93     } while (0)
94 
95 static void ipmi_kcs_signal(IPMIKCS *ik, IPMIInterface *ii)
96 {
97     IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
98 
99     ik->do_wake = 1;
100     while (ik->do_wake) {
101         ik->do_wake = 0;
102         iic->handle_if_event(ii);
103     }
104 }
105 
106 static void ipmi_kcs_handle_event(IPMIInterface *ii)
107 {
108     IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
109     IPMIKCS *ik = iic->get_backend_data(ii);
110 
111     if (ik->cmd_reg == IPMI_KCS_ABORT_STATUS_CMD) {
112         if (IPMI_KCS_GET_STATE(ik->status_reg) != IPMI_KCS_ERROR_STATE) {
113             ik->waiting_rsp++; /* Invalidate the message */
114             ik->outmsg[0] = IPMI_KCS_STATUS_ABORTED_ERR;
115             ik->outlen = 1;
116             ik->outpos = 0;
117             IPMI_KCS_SET_STATE(ik->status_reg, IPMI_KCS_ERROR_STATE);
118             SET_OBF();
119         }
120         goto out;
121     }
122 
123     switch (IPMI_KCS_GET_STATE(ik->status_reg)) {
124     case IPMI_KCS_IDLE_STATE:
125         if (ik->cmd_reg == IPMI_KCS_WRITE_START_CMD) {
126             IPMI_KCS_SET_STATE(ik->status_reg, IPMI_KCS_WRITE_STATE);
127             ik->cmd_reg = -1;
128             ik->write_end = 0;
129             ik->inlen = 0;
130             SET_OBF();
131         }
132         break;
133 
134     case IPMI_KCS_READ_STATE:
135     handle_read:
136         if (ik->outpos >= ik->outlen) {
137             IPMI_KCS_SET_STATE(ik->status_reg, IPMI_KCS_IDLE_STATE);
138             SET_OBF();
139         } else if (ik->data_in_reg == IPMI_KCS_READ_CMD) {
140             ik->data_out_reg = ik->outmsg[ik->outpos];
141             ik->outpos++;
142             SET_OBF();
143         } else {
144             ik->outmsg[0] = IPMI_KCS_STATUS_BAD_CC_ERR;
145             ik->outlen = 1;
146             ik->outpos = 0;
147             IPMI_KCS_SET_STATE(ik->status_reg, IPMI_KCS_ERROR_STATE);
148             SET_OBF();
149             goto out;
150         }
151         break;
152 
153     case IPMI_KCS_WRITE_STATE:
154         if (ik->data_in_reg != -1) {
155             /*
156              * Don't worry about input overrun here, that will be
157              * handled in the BMC.
158              */
159             if (ik->inlen < sizeof(ik->inmsg)) {
160                 ik->inmsg[ik->inlen] = ik->data_in_reg;
161             }
162             ik->inlen++;
163         }
164         if (ik->write_end) {
165             IPMIBmcClass *bk = IPMI_BMC_GET_CLASS(ik->bmc);
166             ik->outlen = 0;
167             ik->write_end = 0;
168             ik->outpos = 0;
169             bk->handle_command(ik->bmc, ik->inmsg, ik->inlen, sizeof(ik->inmsg),
170                                ik->waiting_rsp);
171             goto out_noibf;
172         } else if (ik->cmd_reg == IPMI_KCS_WRITE_END_CMD) {
173             ik->cmd_reg = -1;
174             ik->write_end = 1;
175         }
176         SET_OBF();
177         break;
178 
179     case IPMI_KCS_ERROR_STATE:
180         if (ik->data_in_reg != -1) {
181             IPMI_KCS_SET_STATE(ik->status_reg, IPMI_KCS_READ_STATE);
182             ik->data_in_reg = IPMI_KCS_READ_CMD;
183             goto handle_read;
184         }
185         break;
186     }
187 
188     if (ik->cmd_reg != -1) {
189         /* Got an invalid command */
190         ik->outmsg[0] = IPMI_KCS_STATUS_BAD_CC_ERR;
191         ik->outlen = 1;
192         ik->outpos = 0;
193         IPMI_KCS_SET_STATE(ik->status_reg, IPMI_KCS_ERROR_STATE);
194     }
195 
196  out:
197     ik->cmd_reg = -1;
198     ik->data_in_reg = -1;
199     IPMI_KCS_SET_IBF(ik->status_reg, 0);
200  out_noibf:
201     return;
202 }
203 
204 static void ipmi_kcs_handle_rsp(IPMIInterface *ii, uint8_t msg_id,
205                                 unsigned char *rsp, unsigned int rsp_len)
206 {
207     IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
208     IPMIKCS *ik = iic->get_backend_data(ii);
209 
210     if (ik->waiting_rsp == msg_id) {
211         ik->waiting_rsp++;
212         if (rsp_len > sizeof(ik->outmsg)) {
213             ik->outmsg[0] = rsp[0];
214             ik->outmsg[1] = rsp[1];
215             ik->outmsg[2] = IPMI_CC_CANNOT_RETURN_REQ_NUM_BYTES;
216             ik->outlen = 3;
217         } else {
218             memcpy(ik->outmsg, rsp, rsp_len);
219             ik->outlen = rsp_len;
220         }
221         IPMI_KCS_SET_STATE(ik->status_reg, IPMI_KCS_READ_STATE);
222         ik->data_in_reg = IPMI_KCS_READ_CMD;
223         ipmi_kcs_signal(ik, ii);
224     }
225 }
226 
227 
228 static uint64_t ipmi_kcs_ioport_read(void *opaque, hwaddr addr, unsigned size)
229 {
230     IPMIInterface *ii = opaque;
231     IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
232     IPMIKCS *ik = iic->get_backend_data(ii);
233     uint32_t ret;
234 
235     switch (addr & ik->size_mask) {
236     case 0:
237         ret = ik->data_out_reg;
238         IPMI_KCS_SET_OBF(ik->status_reg, 0);
239         if (ik->obf_irq_set) {
240             ik->obf_irq_set = 0;
241             if (!ik->atn_irq_set) {
242                 ipmi_kcs_lower_irq(ik);
243             }
244         }
245         break;
246 
247     case 1:
248         ret = ik->status_reg;
249         if (ik->atn_irq_set) {
250             ik->atn_irq_set = 0;
251             if (!ik->obf_irq_set) {
252                 ipmi_kcs_lower_irq(ik);
253             }
254         }
255         break;
256 
257     default:
258         ret = 0xff;
259     }
260     return ret;
261 }
262 
263 static void ipmi_kcs_ioport_write(void *opaque, hwaddr addr, uint64_t val,
264                                   unsigned size)
265 {
266     IPMIInterface *ii = opaque;
267     IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
268     IPMIKCS *ik = iic->get_backend_data(ii);
269 
270     if (IPMI_KCS_GET_IBF(ik->status_reg)) {
271         return;
272     }
273 
274     switch (addr & ik->size_mask) {
275     case 0:
276         ik->data_in_reg = val;
277         break;
278 
279     case 1:
280         ik->cmd_reg = val;
281         break;
282 
283     default:
284         /* Ignore. */
285         break;
286     }
287     IPMI_KCS_SET_IBF(ik->status_reg, 1);
288     ipmi_kcs_signal(ik, ii);
289 }
290 
291 const MemoryRegionOps ipmi_kcs_io_ops = {
292     .read = ipmi_kcs_ioport_read,
293     .write = ipmi_kcs_ioport_write,
294     .impl = {
295         .min_access_size = 1,
296         .max_access_size = 1,
297     },
298     .endianness = DEVICE_LITTLE_ENDIAN,
299 };
300 
301 static void ipmi_kcs_set_atn(IPMIInterface *ii, int val, int irq)
302 {
303     IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
304     IPMIKCS *ik = iic->get_backend_data(ii);
305 
306     IPMI_KCS_SET_SMS_ATN(ik->status_reg, val);
307     if (val) {
308         if (irq && !ik->atn_irq_set) {
309             ik->atn_irq_set = 1;
310             if (!ik->obf_irq_set) {
311                 ipmi_kcs_raise_irq(ik);
312             }
313         }
314     } else {
315         if (ik->atn_irq_set) {
316             ik->atn_irq_set = 0;
317             if (!ik->obf_irq_set) {
318                 ipmi_kcs_lower_irq(ik);
319             }
320         }
321     }
322 }
323 
324 static void ipmi_kcs_set_irq_enable(IPMIInterface *ii, int val)
325 {
326     IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
327     IPMIKCS *ik = iic->get_backend_data(ii);
328 
329     ik->irqs_enabled = val;
330 }
331 
332 /* min_size must be a power of 2. */
333 static void ipmi_kcs_init(IPMIInterface *ii, unsigned int min_size,
334                           Error **errp)
335 {
336     IPMIInterfaceClass *iic = IPMI_INTERFACE_GET_CLASS(ii);
337     IPMIKCS *ik = iic->get_backend_data(ii);
338 
339     if (min_size == 0) {
340         min_size = 2;
341     }
342     ik->size_mask = min_size - 1;
343     ik->io_length = 2;
344     memory_region_init_io(&ik->io, NULL, &ipmi_kcs_io_ops, ii, "ipmi-kcs",
345                           min_size);
346 }
347 
348 int ipmi_kcs_vmstate_post_load(void *opaque, int version)
349 {
350     IPMIKCS *ik = opaque;
351 
352     /* Make sure all the values are sane. */
353     if (ik->outpos >= MAX_IPMI_MSG_SIZE || ik->outlen >= MAX_IPMI_MSG_SIZE ||
354         ik->outpos >= ik->outlen) {
355         qemu_log_mask(LOG_GUEST_ERROR,
356                       "ipmi:kcs: vmstate transfer received bad out values: %d %d\n",
357                       ik->outpos, ik->outlen);
358         ik->outpos = 0;
359         ik->outlen = 0;
360     }
361 
362     if (ik->inlen >= MAX_IPMI_MSG_SIZE) {
363         qemu_log_mask(LOG_GUEST_ERROR,
364                       "ipmi:kcs: vmstate transfer received bad in value: %d\n",
365                       ik->inlen);
366         ik->inlen = 0;
367     }
368 
369     return 0;
370 }
371 
372 static bool vmstate_kcs_before_version2(void *opaque, int version)
373 {
374     return version <= 1;
375 }
376 
377 const VMStateDescription vmstate_IPMIKCS = {
378     .name = TYPE_IPMI_INTERFACE_PREFIX "kcs",
379     .version_id = 2,
380     .minimum_version_id = 1,
381     .post_load = ipmi_kcs_vmstate_post_load,
382     .fields = (const VMStateField[]) {
383         VMSTATE_BOOL(obf_irq_set, IPMIKCS),
384         VMSTATE_BOOL(atn_irq_set, IPMIKCS),
385         VMSTATE_UNUSED_TEST(vmstate_kcs_before_version2, 1), /* Was use_irq */
386         VMSTATE_BOOL(irqs_enabled, IPMIKCS),
387         VMSTATE_UINT32(outpos, IPMIKCS),
388         VMSTATE_UINT32_V(outlen, IPMIKCS, 2),
389         VMSTATE_UINT8_ARRAY(outmsg, IPMIKCS, MAX_IPMI_MSG_SIZE),
390         VMSTATE_UINT32_V(inlen, IPMIKCS, 2),
391         VMSTATE_UINT8_ARRAY(inmsg, IPMIKCS, MAX_IPMI_MSG_SIZE),
392         VMSTATE_BOOL(write_end, IPMIKCS),
393         VMSTATE_UINT8(status_reg, IPMIKCS),
394         VMSTATE_UINT8(data_out_reg, IPMIKCS),
395         VMSTATE_INT16(data_in_reg, IPMIKCS),
396         VMSTATE_INT16(cmd_reg, IPMIKCS),
397         VMSTATE_UINT8(waiting_rsp, IPMIKCS),
398         VMSTATE_END_OF_LIST()
399     }
400 };
401 
402 void ipmi_kcs_get_fwinfo(IPMIKCS *ik, IPMIFwInfo *info)
403 {
404     info->interface_name = "kcs";
405     info->interface_type = IPMI_SMBIOS_KCS;
406     info->ipmi_spec_major_revision = 2;
407     info->ipmi_spec_minor_revision = 0;
408     info->base_address = ik->io_base;
409     info->i2c_slave_address = ik->bmc->slave_addr;
410     info->register_length = ik->io_length;
411     info->register_spacing = 1;
412     info->memspace = IPMI_MEMSPACE_IO;
413     info->irq_type = IPMI_LEVEL_IRQ;
414 }
415 
416 void ipmi_kcs_class_init(IPMIInterfaceClass *iic)
417 {
418     iic->init = ipmi_kcs_init;
419     iic->set_atn = ipmi_kcs_set_atn;
420     iic->handle_rsp = ipmi_kcs_handle_rsp;
421     iic->handle_if_event = ipmi_kcs_handle_event;
422     iic->set_irq_enable = ipmi_kcs_set_irq_enable;
423 }
424