xref: /qemu/hw/tpm/tpm_tis_common.c (revision e6b703f6c7a88f84c62d9b8335ee8f451caa9bda)
1 /*
2  * tpm_tis.c - QEMU's TPM TIS interface emulator
3  *
4  * Copyright (C) 2006,2010-2013 IBM Corporation
5  *
6  * Authors:
7  *  Stefan Berger <stefanb@us.ibm.com>
8  *  David Safford <safford@us.ibm.com>
9  *
10  * Xen 4 support: Andrease Niederl <andreas.niederl@iaik.tugraz.at>
11  *
12  * This work is licensed under the terms of the GNU GPL, version 2 or later.
13  * See the COPYING file in the top-level directory.
14  *
15  * Implementation of the TIS interface according to specs found at
16  * http://www.trustedcomputinggroup.org. This implementation currently
17  * supports version 1.3, 21 March 2013
18  * In the developers menu choose the PC Client section then find the TIS
19  * specification.
20  *
21  * TPM TIS for TPM 2 implementation following TCG PC Client Platform
22  * TPM Profile (PTP) Specification, Familiy 2.0, Revision 00.43
23  */
24 
25 #include "qemu/osdep.h"
26 #include "hw/isa/isa.h"
27 #include "qapi/error.h"
28 
29 #include "hw/acpi/tpm.h"
30 #include "hw/pci/pci_ids.h"
31 #include "sysemu/tpm_backend.h"
32 #include "tpm_int.h"
33 #include "tpm_util.h"
34 
35 #define TPM_TIS_NUM_LOCALITIES      5     /* per spec */
36 #define TPM_TIS_LOCALITY_SHIFT      12
37 #define TPM_TIS_NO_LOCALITY         0xff
38 
39 #define TPM_TIS_IS_VALID_LOCTY(x)   ((x) < TPM_TIS_NUM_LOCALITIES)
40 
41 #define TPM_TIS_BUFFER_MAX          4096
42 
43 typedef enum {
44     TPM_TIS_STATE_IDLE = 0,
45     TPM_TIS_STATE_READY,
46     TPM_TIS_STATE_COMPLETION,
47     TPM_TIS_STATE_EXECUTION,
48     TPM_TIS_STATE_RECEPTION,
49 } TPMTISState;
50 
51 typedef struct TPMSizedBuffer {
52     uint32_t size;
53     uint8_t  *buffer;
54 } TPMSizedBuffer;
55 
56 /* locality data  -- all fields are persisted */
57 typedef struct TPMLocality {
58     TPMTISState state;
59     uint8_t access;
60     uint32_t sts;
61     uint32_t iface_id;
62     uint32_t inte;
63     uint32_t ints;
64 
65     uint16_t w_offset;
66     uint16_t r_offset;
67     unsigned char w_buffer[TPM_TIS_BUFFER_MAX];
68     unsigned char r_buffer[TPM_TIS_BUFFER_MAX];
69 } TPMLocality;
70 
71 typedef struct TPMState {
72     ISADevice busdev;
73     MemoryRegion mmio;
74 
75     uint32_t offset;
76     uint8_t buf[TPM_TIS_BUFFER_MAX];
77 
78     uint8_t active_locty;
79     uint8_t aborting_locty;
80     uint8_t next_locty;
81 
82     TPMLocality loc[TPM_TIS_NUM_LOCALITIES];
83 
84     qemu_irq irq;
85     uint32_t irq_num;
86 
87     TPMBackendCmd cmd;
88 
89     TPMBackend *be_driver;
90     TPMVersion be_tpm_version;
91 
92     size_t be_buffer_size;
93 } TPMState;
94 
95 #define TPM(obj) OBJECT_CHECK(TPMState, (obj), TYPE_TPM_TIS)
96 
97 #define DEBUG_TIS 0
98 
99 #define DPRINTF(fmt, ...) do { \
100     if (DEBUG_TIS) { \
101         printf(fmt, ## __VA_ARGS__); \
102     } \
103 } while (0);
104 
105 /* tis registers */
106 #define TPM_TIS_REG_ACCESS                0x00
107 #define TPM_TIS_REG_INT_ENABLE            0x08
108 #define TPM_TIS_REG_INT_VECTOR            0x0c
109 #define TPM_TIS_REG_INT_STATUS            0x10
110 #define TPM_TIS_REG_INTF_CAPABILITY       0x14
111 #define TPM_TIS_REG_STS                   0x18
112 #define TPM_TIS_REG_DATA_FIFO             0x24
113 #define TPM_TIS_REG_INTERFACE_ID          0x30
114 #define TPM_TIS_REG_DATA_XFIFO            0x80
115 #define TPM_TIS_REG_DATA_XFIFO_END        0xbc
116 #define TPM_TIS_REG_DID_VID               0xf00
117 #define TPM_TIS_REG_RID                   0xf04
118 
119 /* vendor-specific registers */
120 #define TPM_TIS_REG_DEBUG                 0xf90
121 
122 #define TPM_TIS_STS_TPM_FAMILY_MASK         (0x3 << 26)/* TPM 2.0 */
123 #define TPM_TIS_STS_TPM_FAMILY1_2           (0 << 26)  /* TPM 2.0 */
124 #define TPM_TIS_STS_TPM_FAMILY2_0           (1 << 26)  /* TPM 2.0 */
125 #define TPM_TIS_STS_RESET_ESTABLISHMENT_BIT (1 << 25)  /* TPM 2.0 */
126 #define TPM_TIS_STS_COMMAND_CANCEL          (1 << 24)  /* TPM 2.0 */
127 
128 #define TPM_TIS_STS_VALID                 (1 << 7)
129 #define TPM_TIS_STS_COMMAND_READY         (1 << 6)
130 #define TPM_TIS_STS_TPM_GO                (1 << 5)
131 #define TPM_TIS_STS_DATA_AVAILABLE        (1 << 4)
132 #define TPM_TIS_STS_EXPECT                (1 << 3)
133 #define TPM_TIS_STS_SELFTEST_DONE         (1 << 2)
134 #define TPM_TIS_STS_RESPONSE_RETRY        (1 << 1)
135 
136 #define TPM_TIS_BURST_COUNT_SHIFT         8
137 #define TPM_TIS_BURST_COUNT(X) \
138     ((X) << TPM_TIS_BURST_COUNT_SHIFT)
139 
140 #define TPM_TIS_ACCESS_TPM_REG_VALID_STS  (1 << 7)
141 #define TPM_TIS_ACCESS_ACTIVE_LOCALITY    (1 << 5)
142 #define TPM_TIS_ACCESS_BEEN_SEIZED        (1 << 4)
143 #define TPM_TIS_ACCESS_SEIZE              (1 << 3)
144 #define TPM_TIS_ACCESS_PENDING_REQUEST    (1 << 2)
145 #define TPM_TIS_ACCESS_REQUEST_USE        (1 << 1)
146 #define TPM_TIS_ACCESS_TPM_ESTABLISHMENT  (1 << 0)
147 
148 #define TPM_TIS_INT_ENABLED               (1 << 31)
149 #define TPM_TIS_INT_DATA_AVAILABLE        (1 << 0)
150 #define TPM_TIS_INT_STS_VALID             (1 << 1)
151 #define TPM_TIS_INT_LOCALITY_CHANGED      (1 << 2)
152 #define TPM_TIS_INT_COMMAND_READY         (1 << 7)
153 
154 #define TPM_TIS_INT_POLARITY_MASK         (3 << 3)
155 #define TPM_TIS_INT_POLARITY_LOW_LEVEL    (1 << 3)
156 
157 #define TPM_TIS_INTERRUPTS_SUPPORTED (TPM_TIS_INT_LOCALITY_CHANGED | \
158                                       TPM_TIS_INT_DATA_AVAILABLE   | \
159                                       TPM_TIS_INT_STS_VALID | \
160                                       TPM_TIS_INT_COMMAND_READY)
161 
162 #define TPM_TIS_CAP_INTERFACE_VERSION1_3 (2 << 28)
163 #define TPM_TIS_CAP_INTERFACE_VERSION1_3_FOR_TPM2_0 (3 << 28)
164 #define TPM_TIS_CAP_DATA_TRANSFER_64B    (3 << 9)
165 #define TPM_TIS_CAP_DATA_TRANSFER_LEGACY (0 << 9)
166 #define TPM_TIS_CAP_BURST_COUNT_DYNAMIC  (0 << 8)
167 #define TPM_TIS_CAP_INTERRUPT_LOW_LEVEL  (1 << 4) /* support is mandatory */
168 #define TPM_TIS_CAPABILITIES_SUPPORTED1_3 \
169     (TPM_TIS_CAP_INTERRUPT_LOW_LEVEL | \
170      TPM_TIS_CAP_BURST_COUNT_DYNAMIC | \
171      TPM_TIS_CAP_DATA_TRANSFER_64B | \
172      TPM_TIS_CAP_INTERFACE_VERSION1_3 | \
173      TPM_TIS_INTERRUPTS_SUPPORTED)
174 
175 #define TPM_TIS_CAPABILITIES_SUPPORTED2_0 \
176     (TPM_TIS_CAP_INTERRUPT_LOW_LEVEL | \
177      TPM_TIS_CAP_BURST_COUNT_DYNAMIC | \
178      TPM_TIS_CAP_DATA_TRANSFER_64B | \
179      TPM_TIS_CAP_INTERFACE_VERSION1_3_FOR_TPM2_0 | \
180      TPM_TIS_INTERRUPTS_SUPPORTED)
181 
182 #define TPM_TIS_IFACE_ID_INTERFACE_TIS1_3   (0xf)     /* TPM 2.0 */
183 #define TPM_TIS_IFACE_ID_INTERFACE_FIFO     (0x0)     /* TPM 2.0 */
184 #define TPM_TIS_IFACE_ID_INTERFACE_VER_FIFO (0 << 4)  /* TPM 2.0 */
185 #define TPM_TIS_IFACE_ID_CAP_5_LOCALITIES   (1 << 8)  /* TPM 2.0 */
186 #define TPM_TIS_IFACE_ID_CAP_TIS_SUPPORTED  (1 << 13) /* TPM 2.0 */
187 #define TPM_TIS_IFACE_ID_INT_SEL_LOCK       (1 << 19) /* TPM 2.0 */
188 
189 #define TPM_TIS_IFACE_ID_SUPPORTED_FLAGS1_3 \
190     (TPM_TIS_IFACE_ID_INTERFACE_TIS1_3 | \
191      (~0u << 4)/* all of it is don't care */)
192 
193 /* if backend was a TPM 2.0: */
194 #define TPM_TIS_IFACE_ID_SUPPORTED_FLAGS2_0 \
195     (TPM_TIS_IFACE_ID_INTERFACE_FIFO | \
196      TPM_TIS_IFACE_ID_INTERFACE_VER_FIFO | \
197      TPM_TIS_IFACE_ID_CAP_5_LOCALITIES | \
198      TPM_TIS_IFACE_ID_CAP_TIS_SUPPORTED)
199 
200 #define TPM_TIS_TPM_DID       0x0001
201 #define TPM_TIS_TPM_VID       PCI_VENDOR_ID_IBM
202 #define TPM_TIS_TPM_RID       0x0001
203 
204 #define TPM_TIS_NO_DATA_BYTE  0xff
205 
206 /* local prototypes */
207 
208 static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr addr,
209                                   unsigned size);
210 
211 /* utility functions */
212 
213 static uint8_t tpm_tis_locality_from_addr(hwaddr addr)
214 {
215     return (uint8_t)((addr >> TPM_TIS_LOCALITY_SHIFT) & 0x7);
216 }
217 
218 static void tpm_tis_show_buffer(const unsigned char *buffer,
219                                 size_t buffer_size, const char *string)
220 {
221 #ifdef DEBUG_TIS
222     uint32_t len, i;
223 
224     len = MIN(tpm_cmd_get_size(buffer), buffer_size);
225     DPRINTF("tpm_tis: %s length = %d\n", string, len);
226     for (i = 0; i < len; i++) {
227         if (i && !(i % 16)) {
228             DPRINTF("\n");
229         }
230         DPRINTF("%.2X ", buffer[i]);
231     }
232     DPRINTF("\n");
233 #endif
234 }
235 
236 /*
237  * Set the given flags in the STS register by clearing the register but
238  * preserving the SELFTEST_DONE and TPM_FAMILY_MASK flags and then setting
239  * the new flags.
240  *
241  * The SELFTEST_DONE flag is acquired from the backend that determines it by
242  * peeking into TPM commands.
243  *
244  * A VM suspend/resume will preserve the flag by storing it into the VM
245  * device state, but the backend will not remember it when QEMU is started
246  * again. Therefore, we cache the flag here. Once set, it will not be unset
247  * except by a reset.
248  */
249 static void tpm_tis_sts_set(TPMLocality *l, uint32_t flags)
250 {
251     l->sts &= TPM_TIS_STS_SELFTEST_DONE | TPM_TIS_STS_TPM_FAMILY_MASK;
252     l->sts |= flags;
253 }
254 
255 /*
256  * Send a request to the TPM.
257  */
258 static void tpm_tis_tpm_send(TPMState *s, uint8_t locty)
259 {
260     TPMLocality *locty_data = &s->loc[locty];
261 
262     tpm_tis_show_buffer(s->loc[locty].w_buffer, s->be_buffer_size,
263                         "tpm_tis: To TPM");
264 
265     /*
266      * w_offset serves as length indicator for length of data;
267      * it's reset when the response comes back
268      */
269     s->loc[locty].state = TPM_TIS_STATE_EXECUTION;
270 
271     s->cmd = (TPMBackendCmd) {
272         .locty = locty,
273         .in = locty_data->w_buffer,
274         .in_len = locty_data->w_offset,
275         .out = locty_data->r_buffer,
276         .out_len = s->be_buffer_size,
277     };
278 
279     tpm_backend_deliver_request(s->be_driver, &s->cmd);
280 }
281 
282 /* raise an interrupt if allowed */
283 static void tpm_tis_raise_irq(TPMState *s, uint8_t locty, uint32_t irqmask)
284 {
285     if (!TPM_TIS_IS_VALID_LOCTY(locty)) {
286         return;
287     }
288 
289     if ((s->loc[locty].inte & TPM_TIS_INT_ENABLED) &&
290         (s->loc[locty].inte & irqmask)) {
291         DPRINTF("tpm_tis: Raising IRQ for flag %08x\n", irqmask);
292         qemu_irq_raise(s->irq);
293         s->loc[locty].ints |= irqmask;
294     }
295 }
296 
297 static uint32_t tpm_tis_check_request_use_except(TPMState *s, uint8_t locty)
298 {
299     uint8_t l;
300 
301     for (l = 0; l < TPM_TIS_NUM_LOCALITIES; l++) {
302         if (l == locty) {
303             continue;
304         }
305         if ((s->loc[l].access & TPM_TIS_ACCESS_REQUEST_USE)) {
306             return 1;
307         }
308     }
309 
310     return 0;
311 }
312 
313 static void tpm_tis_new_active_locality(TPMState *s, uint8_t new_active_locty)
314 {
315     bool change = (s->active_locty != new_active_locty);
316     bool is_seize;
317     uint8_t mask;
318 
319     if (change && TPM_TIS_IS_VALID_LOCTY(s->active_locty)) {
320         is_seize = TPM_TIS_IS_VALID_LOCTY(new_active_locty) &&
321                    s->loc[new_active_locty].access & TPM_TIS_ACCESS_SEIZE;
322 
323         if (is_seize) {
324             mask = ~(TPM_TIS_ACCESS_ACTIVE_LOCALITY);
325         } else {
326             mask = ~(TPM_TIS_ACCESS_ACTIVE_LOCALITY|
327                      TPM_TIS_ACCESS_REQUEST_USE);
328         }
329         /* reset flags on the old active locality */
330         s->loc[s->active_locty].access &= mask;
331 
332         if (is_seize) {
333             s->loc[s->active_locty].access |= TPM_TIS_ACCESS_BEEN_SEIZED;
334         }
335     }
336 
337     s->active_locty = new_active_locty;
338 
339     DPRINTF("tpm_tis: Active locality is now %d\n", s->active_locty);
340 
341     if (TPM_TIS_IS_VALID_LOCTY(new_active_locty)) {
342         /* set flags on the new active locality */
343         s->loc[new_active_locty].access |= TPM_TIS_ACCESS_ACTIVE_LOCALITY;
344         s->loc[new_active_locty].access &= ~(TPM_TIS_ACCESS_REQUEST_USE |
345                                                TPM_TIS_ACCESS_SEIZE);
346     }
347 
348     if (change) {
349         tpm_tis_raise_irq(s, s->active_locty, TPM_TIS_INT_LOCALITY_CHANGED);
350     }
351 }
352 
353 /* abort -- this function switches the locality */
354 static void tpm_tis_abort(TPMState *s, uint8_t locty)
355 {
356     s->loc[locty].r_offset = 0;
357     s->loc[locty].w_offset = 0;
358 
359     DPRINTF("tpm_tis: tis_abort: new active locality is %d\n", s->next_locty);
360 
361     /*
362      * Need to react differently depending on who's aborting now and
363      * which locality will become active afterwards.
364      */
365     if (s->aborting_locty == s->next_locty) {
366         s->loc[s->aborting_locty].state = TPM_TIS_STATE_READY;
367         tpm_tis_sts_set(&s->loc[s->aborting_locty],
368                         TPM_TIS_STS_COMMAND_READY);
369         tpm_tis_raise_irq(s, s->aborting_locty, TPM_TIS_INT_COMMAND_READY);
370     }
371 
372     /* locality after abort is another one than the current one */
373     tpm_tis_new_active_locality(s, s->next_locty);
374 
375     s->next_locty = TPM_TIS_NO_LOCALITY;
376     /* nobody's aborting a command anymore */
377     s->aborting_locty = TPM_TIS_NO_LOCALITY;
378 }
379 
380 /* prepare aborting current command */
381 static void tpm_tis_prep_abort(TPMState *s, uint8_t locty, uint8_t newlocty)
382 {
383     uint8_t busy_locty;
384 
385     s->aborting_locty = locty;
386     s->next_locty = newlocty;  /* locality after successful abort */
387 
388     /*
389      * only abort a command using an interrupt if currently executing
390      * a command AND if there's a valid connection to the vTPM.
391      */
392     for (busy_locty = 0; busy_locty < TPM_TIS_NUM_LOCALITIES; busy_locty++) {
393         if (s->loc[busy_locty].state == TPM_TIS_STATE_EXECUTION) {
394             /*
395              * request the backend to cancel. Some backends may not
396              * support it
397              */
398             tpm_backend_cancel_cmd(s->be_driver);
399             return;
400         }
401     }
402 
403     tpm_tis_abort(s, locty);
404 }
405 
406 /*
407  * Callback from the TPM to indicate that the response was received.
408  */
409 static void tpm_tis_request_completed(TPMIf *ti)
410 {
411     TPMState *s = TPM(ti);
412     uint8_t locty = s->cmd.locty;
413     uint8_t l;
414 
415     if (s->cmd.selftest_done) {
416         for (l = 0; l < TPM_TIS_NUM_LOCALITIES; l++) {
417             s->loc[locty].sts |= TPM_TIS_STS_SELFTEST_DONE;
418         }
419     }
420 
421     tpm_tis_sts_set(&s->loc[locty],
422                     TPM_TIS_STS_VALID | TPM_TIS_STS_DATA_AVAILABLE);
423     s->loc[locty].state = TPM_TIS_STATE_COMPLETION;
424     s->loc[locty].r_offset = 0;
425     s->loc[locty].w_offset = 0;
426 
427     tpm_tis_show_buffer(s->loc[locty].r_buffer, s->be_buffer_size,
428                         "tpm_tis: From TPM");
429 
430     if (TPM_TIS_IS_VALID_LOCTY(s->next_locty)) {
431         tpm_tis_abort(s, locty);
432     }
433 
434     tpm_tis_raise_irq(s, locty,
435                       TPM_TIS_INT_DATA_AVAILABLE | TPM_TIS_INT_STS_VALID);
436 }
437 
438 /*
439  * Read a byte of response data
440  */
441 static uint32_t tpm_tis_data_read(TPMState *s, uint8_t locty)
442 {
443     uint32_t ret = TPM_TIS_NO_DATA_BYTE;
444     uint16_t len;
445 
446     if ((s->loc[locty].sts & TPM_TIS_STS_DATA_AVAILABLE)) {
447         len = MIN(tpm_cmd_get_size(&s->loc[locty].r_buffer),
448                   s->be_buffer_size);
449 
450         ret = s->loc[locty].r_buffer[s->loc[locty].r_offset++];
451         if (s->loc[locty].r_offset >= len) {
452             /* got last byte */
453             tpm_tis_sts_set(&s->loc[locty], TPM_TIS_STS_VALID);
454             tpm_tis_raise_irq(s, locty, TPM_TIS_INT_STS_VALID);
455         }
456         DPRINTF("tpm_tis: tpm_tis_data_read byte 0x%02x   [%d]\n",
457                 ret, s->loc[locty].r_offset - 1);
458     }
459 
460     return ret;
461 }
462 
463 #ifdef DEBUG_TIS
464 static void tpm_tis_dump_state(void *opaque, hwaddr addr)
465 {
466     static const unsigned regs[] = {
467         TPM_TIS_REG_ACCESS,
468         TPM_TIS_REG_INT_ENABLE,
469         TPM_TIS_REG_INT_VECTOR,
470         TPM_TIS_REG_INT_STATUS,
471         TPM_TIS_REG_INTF_CAPABILITY,
472         TPM_TIS_REG_STS,
473         TPM_TIS_REG_DID_VID,
474         TPM_TIS_REG_RID,
475         0xfff};
476     int idx;
477     uint8_t locty = tpm_tis_locality_from_addr(addr);
478     hwaddr base = addr & ~0xfff;
479     TPMState *s = opaque;
480 
481     DPRINTF("tpm_tis: active locality      : %d\n"
482             "tpm_tis: state of locality %d : %d\n"
483             "tpm_tis: register dump:\n",
484             s->active_locty,
485             locty, s->loc[locty].state);
486 
487     for (idx = 0; regs[idx] != 0xfff; idx++) {
488         DPRINTF("tpm_tis: 0x%04x : 0x%08x\n", regs[idx],
489                 (int)tpm_tis_mmio_read(opaque, base + regs[idx], 4));
490     }
491 
492     DPRINTF("tpm_tis: read offset   : %d\n"
493             "tpm_tis: result buffer : ",
494             s->loc[locty].r_offset);
495     for (idx = 0;
496          idx < MIN(tpm_cmd_get_size(&s->loc[locty].r_buffer),
497                    s->be_buffer_size);
498          idx++) {
499         DPRINTF("%c%02x%s",
500                 s->loc[locty].r_offset == idx ? '>' : ' ',
501                 s->loc[locty].r_buffer[idx],
502                 ((idx & 0xf) == 0xf) ? "\ntpm_tis:                 " : "");
503     }
504     DPRINTF("\n"
505             "tpm_tis: write offset  : %d\n"
506             "tpm_tis: request buffer: ",
507             s->loc[locty].w_offset);
508     for (idx = 0;
509          idx < MIN(tpm_cmd_get_size(s->loc[locty].w_buffer),
510                    s->be_buffer_size);
511          idx++) {
512         DPRINTF("%c%02x%s",
513                 s->loc[locty].w_offset == idx ? '>' : ' ',
514                 s->loc[locty].w_buffer[idx],
515                 ((idx & 0xf) == 0xf) ? "\ntpm_tis:                 " : "");
516     }
517     DPRINTF("\n");
518 }
519 #endif
520 
521 /*
522  * Read a register of the TIS interface
523  * See specs pages 33-63 for description of the registers
524  */
525 static uint64_t tpm_tis_mmio_read(void *opaque, hwaddr addr,
526                                   unsigned size)
527 {
528     TPMState *s = opaque;
529     uint16_t offset = addr & 0xffc;
530     uint8_t shift = (addr & 0x3) * 8;
531     uint32_t val = 0xffffffff;
532     uint8_t locty = tpm_tis_locality_from_addr(addr);
533     uint32_t avail;
534     uint8_t v;
535 
536     if (tpm_backend_had_startup_error(s->be_driver)) {
537         return 0;
538     }
539 
540     switch (offset) {
541     case TPM_TIS_REG_ACCESS:
542         /* never show the SEIZE flag even though we use it internally */
543         val = s->loc[locty].access & ~TPM_TIS_ACCESS_SEIZE;
544         /* the pending flag is always calculated */
545         if (tpm_tis_check_request_use_except(s, locty)) {
546             val |= TPM_TIS_ACCESS_PENDING_REQUEST;
547         }
548         val |= !tpm_backend_get_tpm_established_flag(s->be_driver);
549         break;
550     case TPM_TIS_REG_INT_ENABLE:
551         val = s->loc[locty].inte;
552         break;
553     case TPM_TIS_REG_INT_VECTOR:
554         val = s->irq_num;
555         break;
556     case TPM_TIS_REG_INT_STATUS:
557         val = s->loc[locty].ints;
558         break;
559     case TPM_TIS_REG_INTF_CAPABILITY:
560         switch (s->be_tpm_version) {
561         case TPM_VERSION_UNSPEC:
562             val = 0;
563             break;
564         case TPM_VERSION_1_2:
565             val = TPM_TIS_CAPABILITIES_SUPPORTED1_3;
566             break;
567         case TPM_VERSION_2_0:
568             val = TPM_TIS_CAPABILITIES_SUPPORTED2_0;
569             break;
570         }
571         break;
572     case TPM_TIS_REG_STS:
573         if (s->active_locty == locty) {
574             if ((s->loc[locty].sts & TPM_TIS_STS_DATA_AVAILABLE)) {
575                 val = TPM_TIS_BURST_COUNT(
576                        MIN(tpm_cmd_get_size(&s->loc[locty].r_buffer),
577                            s->be_buffer_size)
578                        - s->loc[locty].r_offset) | s->loc[locty].sts;
579             } else {
580                 avail = s->be_buffer_size - s->loc[locty].w_offset;
581                 /*
582                  * byte-sized reads should not return 0x00 for 0x100
583                  * available bytes.
584                  */
585                 if (size == 1 && avail > 0xff) {
586                     avail = 0xff;
587                 }
588                 val = TPM_TIS_BURST_COUNT(avail) | s->loc[locty].sts;
589             }
590         }
591         break;
592     case TPM_TIS_REG_DATA_FIFO:
593     case TPM_TIS_REG_DATA_XFIFO ... TPM_TIS_REG_DATA_XFIFO_END:
594         if (s->active_locty == locty) {
595             if (size > 4 - (addr & 0x3)) {
596                 /* prevent access beyond FIFO */
597                 size = 4 - (addr & 0x3);
598             }
599             val = 0;
600             shift = 0;
601             while (size > 0) {
602                 switch (s->loc[locty].state) {
603                 case TPM_TIS_STATE_COMPLETION:
604                     v = tpm_tis_data_read(s, locty);
605                     break;
606                 default:
607                     v = TPM_TIS_NO_DATA_BYTE;
608                     break;
609                 }
610                 val |= (v << shift);
611                 shift += 8;
612                 size--;
613             }
614             shift = 0; /* no more adjustments */
615         }
616         break;
617     case TPM_TIS_REG_INTERFACE_ID:
618         val = s->loc[locty].iface_id;
619         break;
620     case TPM_TIS_REG_DID_VID:
621         val = (TPM_TIS_TPM_DID << 16) | TPM_TIS_TPM_VID;
622         break;
623     case TPM_TIS_REG_RID:
624         val = TPM_TIS_TPM_RID;
625         break;
626 #ifdef DEBUG_TIS
627     case TPM_TIS_REG_DEBUG:
628         tpm_tis_dump_state(opaque, addr);
629         break;
630 #endif
631     }
632 
633     if (shift) {
634         val >>= shift;
635     }
636 
637     DPRINTF("tpm_tis:  read.%u(%08x) = %08x\n", size, (int)addr, (int)val);
638 
639     return val;
640 }
641 
642 /*
643  * Write a value to a register of the TIS interface
644  * See specs pages 33-63 for description of the registers
645  */
646 static void tpm_tis_mmio_write(void *opaque, hwaddr addr,
647                                uint64_t val, unsigned size)
648 {
649     TPMState *s = opaque;
650     uint16_t off = addr & 0xffc;
651     uint8_t shift = (addr & 0x3) * 8;
652     uint8_t locty = tpm_tis_locality_from_addr(addr);
653     uint8_t active_locty, l;
654     int c, set_new_locty = 1;
655     uint16_t len;
656     uint32_t mask = (size == 1) ? 0xff : ((size == 2) ? 0xffff : ~0);
657 
658     DPRINTF("tpm_tis: write.%u(%08x) = %08x\n", size, (int)addr, (int)val);
659 
660     if (locty == 4) {
661         DPRINTF("tpm_tis: Access to locality 4 only allowed from hardware\n");
662         return;
663     }
664 
665     if (tpm_backend_had_startup_error(s->be_driver)) {
666         return;
667     }
668 
669     val &= mask;
670 
671     if (shift) {
672         val <<= shift;
673         mask <<= shift;
674     }
675 
676     mask ^= 0xffffffff;
677 
678     switch (off) {
679     case TPM_TIS_REG_ACCESS:
680 
681         if ((val & TPM_TIS_ACCESS_SEIZE)) {
682             val &= ~(TPM_TIS_ACCESS_REQUEST_USE |
683                      TPM_TIS_ACCESS_ACTIVE_LOCALITY);
684         }
685 
686         active_locty = s->active_locty;
687 
688         if ((val & TPM_TIS_ACCESS_ACTIVE_LOCALITY)) {
689             /* give up locality if currently owned */
690             if (s->active_locty == locty) {
691                 DPRINTF("tpm_tis: Releasing locality %d\n", locty);
692 
693                 uint8_t newlocty = TPM_TIS_NO_LOCALITY;
694                 /* anybody wants the locality ? */
695                 for (c = TPM_TIS_NUM_LOCALITIES - 1; c >= 0; c--) {
696                     if ((s->loc[c].access & TPM_TIS_ACCESS_REQUEST_USE)) {
697                         DPRINTF("tpm_tis: Locality %d requests use.\n", c);
698                         newlocty = c;
699                         break;
700                     }
701                 }
702                 DPRINTF("tpm_tis: TPM_TIS_ACCESS_ACTIVE_LOCALITY: "
703                         "Next active locality: %d\n",
704                         newlocty);
705 
706                 if (TPM_TIS_IS_VALID_LOCTY(newlocty)) {
707                     set_new_locty = 0;
708                     tpm_tis_prep_abort(s, locty, newlocty);
709                 } else {
710                     active_locty = TPM_TIS_NO_LOCALITY;
711                 }
712             } else {
713                 /* not currently the owner; clear a pending request */
714                 s->loc[locty].access &= ~TPM_TIS_ACCESS_REQUEST_USE;
715             }
716         }
717 
718         if ((val & TPM_TIS_ACCESS_BEEN_SEIZED)) {
719             s->loc[locty].access &= ~TPM_TIS_ACCESS_BEEN_SEIZED;
720         }
721 
722         if ((val & TPM_TIS_ACCESS_SEIZE)) {
723             /*
724              * allow seize if a locality is active and the requesting
725              * locality is higher than the one that's active
726              * OR
727              * allow seize for requesting locality if no locality is
728              * active
729              */
730             while ((TPM_TIS_IS_VALID_LOCTY(s->active_locty) &&
731                     locty > s->active_locty) ||
732                     !TPM_TIS_IS_VALID_LOCTY(s->active_locty)) {
733                 bool higher_seize = FALSE;
734 
735                 /* already a pending SEIZE ? */
736                 if ((s->loc[locty].access & TPM_TIS_ACCESS_SEIZE)) {
737                     break;
738                 }
739 
740                 /* check for ongoing seize by a higher locality */
741                 for (l = locty + 1; l < TPM_TIS_NUM_LOCALITIES; l++) {
742                     if ((s->loc[l].access & TPM_TIS_ACCESS_SEIZE)) {
743                         higher_seize = TRUE;
744                         break;
745                     }
746                 }
747 
748                 if (higher_seize) {
749                     break;
750                 }
751 
752                 /* cancel any seize by a lower locality */
753                 for (l = 0; l < locty - 1; l++) {
754                     s->loc[l].access &= ~TPM_TIS_ACCESS_SEIZE;
755                 }
756 
757                 s->loc[locty].access |= TPM_TIS_ACCESS_SEIZE;
758                 DPRINTF("tpm_tis: TPM_TIS_ACCESS_SEIZE: "
759                         "Locality %d seized from locality %d\n",
760                         locty, s->active_locty);
761                 DPRINTF("tpm_tis: TPM_TIS_ACCESS_SEIZE: Initiating abort.\n");
762                 set_new_locty = 0;
763                 tpm_tis_prep_abort(s, s->active_locty, locty);
764                 break;
765             }
766         }
767 
768         if ((val & TPM_TIS_ACCESS_REQUEST_USE)) {
769             if (s->active_locty != locty) {
770                 if (TPM_TIS_IS_VALID_LOCTY(s->active_locty)) {
771                     s->loc[locty].access |= TPM_TIS_ACCESS_REQUEST_USE;
772                 } else {
773                     /* no locality active -> make this one active now */
774                     active_locty = locty;
775                 }
776             }
777         }
778 
779         if (set_new_locty) {
780             tpm_tis_new_active_locality(s, active_locty);
781         }
782 
783         break;
784     case TPM_TIS_REG_INT_ENABLE:
785         if (s->active_locty != locty) {
786             break;
787         }
788 
789         s->loc[locty].inte &= mask;
790         s->loc[locty].inte |= (val & (TPM_TIS_INT_ENABLED |
791                                         TPM_TIS_INT_POLARITY_MASK |
792                                         TPM_TIS_INTERRUPTS_SUPPORTED));
793         break;
794     case TPM_TIS_REG_INT_VECTOR:
795         /* hard wired -- ignore */
796         break;
797     case TPM_TIS_REG_INT_STATUS:
798         if (s->active_locty != locty) {
799             break;
800         }
801 
802         /* clearing of interrupt flags */
803         if (((val & TPM_TIS_INTERRUPTS_SUPPORTED)) &&
804             (s->loc[locty].ints & TPM_TIS_INTERRUPTS_SUPPORTED)) {
805             s->loc[locty].ints &= ~val;
806             if (s->loc[locty].ints == 0) {
807                 qemu_irq_lower(s->irq);
808                 DPRINTF("tpm_tis: Lowering IRQ\n");
809             }
810         }
811         s->loc[locty].ints &= ~(val & TPM_TIS_INTERRUPTS_SUPPORTED);
812         break;
813     case TPM_TIS_REG_STS:
814         if (s->active_locty != locty) {
815             break;
816         }
817 
818         if (s->be_tpm_version == TPM_VERSION_2_0) {
819             /* some flags that are only supported for TPM 2 */
820             if (val & TPM_TIS_STS_COMMAND_CANCEL) {
821                 if (s->loc[locty].state == TPM_TIS_STATE_EXECUTION) {
822                     /*
823                      * request the backend to cancel. Some backends may not
824                      * support it
825                      */
826                     tpm_backend_cancel_cmd(s->be_driver);
827                 }
828             }
829 
830             if (val & TPM_TIS_STS_RESET_ESTABLISHMENT_BIT) {
831                 if (locty == 3 || locty == 4) {
832                     tpm_backend_reset_tpm_established_flag(s->be_driver, locty);
833                 }
834             }
835         }
836 
837         val &= (TPM_TIS_STS_COMMAND_READY | TPM_TIS_STS_TPM_GO |
838                 TPM_TIS_STS_RESPONSE_RETRY);
839 
840         if (val == TPM_TIS_STS_COMMAND_READY) {
841             switch (s->loc[locty].state) {
842 
843             case TPM_TIS_STATE_READY:
844                 s->loc[locty].w_offset = 0;
845                 s->loc[locty].r_offset = 0;
846             break;
847 
848             case TPM_TIS_STATE_IDLE:
849                 tpm_tis_sts_set(&s->loc[locty], TPM_TIS_STS_COMMAND_READY);
850                 s->loc[locty].state = TPM_TIS_STATE_READY;
851                 tpm_tis_raise_irq(s, locty, TPM_TIS_INT_COMMAND_READY);
852             break;
853 
854             case TPM_TIS_STATE_EXECUTION:
855             case TPM_TIS_STATE_RECEPTION:
856                 /* abort currently running command */
857                 DPRINTF("tpm_tis: %s: Initiating abort.\n",
858                         __func__);
859                 tpm_tis_prep_abort(s, locty, locty);
860             break;
861 
862             case TPM_TIS_STATE_COMPLETION:
863                 s->loc[locty].w_offset = 0;
864                 s->loc[locty].r_offset = 0;
865                 /* shortcut to ready state with C/R set */
866                 s->loc[locty].state = TPM_TIS_STATE_READY;
867                 if (!(s->loc[locty].sts & TPM_TIS_STS_COMMAND_READY)) {
868                     tpm_tis_sts_set(&s->loc[locty],
869                                     TPM_TIS_STS_COMMAND_READY);
870                     tpm_tis_raise_irq(s, locty, TPM_TIS_INT_COMMAND_READY);
871                 }
872                 s->loc[locty].sts &= ~(TPM_TIS_STS_DATA_AVAILABLE);
873             break;
874 
875             }
876         } else if (val == TPM_TIS_STS_TPM_GO) {
877             switch (s->loc[locty].state) {
878             case TPM_TIS_STATE_RECEPTION:
879                 if ((s->loc[locty].sts & TPM_TIS_STS_EXPECT) == 0) {
880                     tpm_tis_tpm_send(s, locty);
881                 }
882                 break;
883             default:
884                 /* ignore */
885                 break;
886             }
887         } else if (val == TPM_TIS_STS_RESPONSE_RETRY) {
888             switch (s->loc[locty].state) {
889             case TPM_TIS_STATE_COMPLETION:
890                 s->loc[locty].r_offset = 0;
891                 tpm_tis_sts_set(&s->loc[locty],
892                                 TPM_TIS_STS_VALID|
893                                 TPM_TIS_STS_DATA_AVAILABLE);
894                 break;
895             default:
896                 /* ignore */
897                 break;
898             }
899         }
900         break;
901     case TPM_TIS_REG_DATA_FIFO:
902     case TPM_TIS_REG_DATA_XFIFO ... TPM_TIS_REG_DATA_XFIFO_END:
903         /* data fifo */
904         if (s->active_locty != locty) {
905             break;
906         }
907 
908         if (s->loc[locty].state == TPM_TIS_STATE_IDLE ||
909             s->loc[locty].state == TPM_TIS_STATE_EXECUTION ||
910             s->loc[locty].state == TPM_TIS_STATE_COMPLETION) {
911             /* drop the byte */
912         } else {
913             DPRINTF("tpm_tis: Data to send to TPM: %08x (size=%d)\n",
914                     (int)val, size);
915             if (s->loc[locty].state == TPM_TIS_STATE_READY) {
916                 s->loc[locty].state = TPM_TIS_STATE_RECEPTION;
917                 tpm_tis_sts_set(&s->loc[locty],
918                                 TPM_TIS_STS_EXPECT | TPM_TIS_STS_VALID);
919             }
920 
921             val >>= shift;
922             if (size > 4 - (addr & 0x3)) {
923                 /* prevent access beyond FIFO */
924                 size = 4 - (addr & 0x3);
925             }
926 
927             while ((s->loc[locty].sts & TPM_TIS_STS_EXPECT) && size > 0) {
928                 if (s->loc[locty].w_offset < s->be_buffer_size) {
929                     s->loc[locty].w_buffer[s->loc[locty].w_offset++] =
930                         (uint8_t)val;
931                     val >>= 8;
932                     size--;
933                 } else {
934                     tpm_tis_sts_set(&s->loc[locty], TPM_TIS_STS_VALID);
935                 }
936             }
937 
938             /* check for complete packet */
939             if (s->loc[locty].w_offset > 5 &&
940                 (s->loc[locty].sts & TPM_TIS_STS_EXPECT)) {
941                 /* we have a packet length - see if we have all of it */
942                 bool need_irq = !(s->loc[locty].sts & TPM_TIS_STS_VALID);
943 
944                 len = tpm_cmd_get_size(&s->loc[locty].w_buffer);
945                 if (len > s->loc[locty].w_offset) {
946                     tpm_tis_sts_set(&s->loc[locty],
947                                     TPM_TIS_STS_EXPECT | TPM_TIS_STS_VALID);
948                 } else {
949                     /* packet complete */
950                     tpm_tis_sts_set(&s->loc[locty], TPM_TIS_STS_VALID);
951                 }
952                 if (need_irq) {
953                     tpm_tis_raise_irq(s, locty, TPM_TIS_INT_STS_VALID);
954                 }
955             }
956         }
957         break;
958     case TPM_TIS_REG_INTERFACE_ID:
959         if (val & TPM_TIS_IFACE_ID_INT_SEL_LOCK) {
960             for (l = 0; l < TPM_TIS_NUM_LOCALITIES; l++) {
961                 s->loc[l].iface_id |= TPM_TIS_IFACE_ID_INT_SEL_LOCK;
962             }
963         }
964         break;
965     }
966 }
967 
968 static const MemoryRegionOps tpm_tis_memory_ops = {
969     .read = tpm_tis_mmio_read,
970     .write = tpm_tis_mmio_write,
971     .endianness = DEVICE_LITTLE_ENDIAN,
972     .valid = {
973         .min_access_size = 1,
974         .max_access_size = 4,
975     },
976 };
977 
978 static int tpm_tis_do_startup_tpm(TPMState *s, size_t buffersize)
979 {
980     return tpm_backend_startup_tpm(s->be_driver, buffersize);
981 }
982 
983 /*
984  * Get the TPMVersion of the backend device being used
985  */
986 static enum TPMVersion tpm_tis_get_tpm_version(TPMIf *ti)
987 {
988     TPMState *s = TPM(ti);
989 
990     if (tpm_backend_had_startup_error(s->be_driver)) {
991         return TPM_VERSION_UNSPEC;
992     }
993 
994     return tpm_backend_get_tpm_version(s->be_driver);
995 }
996 
997 /*
998  * This function is called when the machine starts, resets or due to
999  * S3 resume.
1000  */
1001 static void tpm_tis_reset(DeviceState *dev)
1002 {
1003     TPMState *s = TPM(dev);
1004     int c;
1005 
1006     s->be_tpm_version = tpm_backend_get_tpm_version(s->be_driver);
1007     s->be_buffer_size = MIN(tpm_backend_get_buffer_size(s->be_driver),
1008                             TPM_TIS_BUFFER_MAX);
1009 
1010     tpm_backend_reset(s->be_driver);
1011 
1012     s->active_locty = TPM_TIS_NO_LOCALITY;
1013     s->next_locty = TPM_TIS_NO_LOCALITY;
1014     s->aborting_locty = TPM_TIS_NO_LOCALITY;
1015 
1016     for (c = 0; c < TPM_TIS_NUM_LOCALITIES; c++) {
1017         s->loc[c].access = TPM_TIS_ACCESS_TPM_REG_VALID_STS;
1018         switch (s->be_tpm_version) {
1019         case TPM_VERSION_UNSPEC:
1020             break;
1021         case TPM_VERSION_1_2:
1022             s->loc[c].sts = TPM_TIS_STS_TPM_FAMILY1_2;
1023             s->loc[c].iface_id = TPM_TIS_IFACE_ID_SUPPORTED_FLAGS1_3;
1024             break;
1025         case TPM_VERSION_2_0:
1026             s->loc[c].sts = TPM_TIS_STS_TPM_FAMILY2_0;
1027             s->loc[c].iface_id = TPM_TIS_IFACE_ID_SUPPORTED_FLAGS2_0;
1028             break;
1029         }
1030         s->loc[c].inte = TPM_TIS_INT_POLARITY_LOW_LEVEL;
1031         s->loc[c].ints = 0;
1032         s->loc[c].state = TPM_TIS_STATE_IDLE;
1033 
1034         s->loc[c].w_offset = 0;
1035         s->loc[c].r_offset = 0;
1036     }
1037 
1038     tpm_tis_do_startup_tpm(s, s->be_buffer_size);
1039 }
1040 
1041 static const VMStateDescription vmstate_tpm_tis = {
1042     .name = "tpm",
1043     .unmigratable = 1,
1044 };
1045 
1046 static Property tpm_tis_properties[] = {
1047     DEFINE_PROP_UINT32("irq", TPMState, irq_num, TPM_TIS_IRQ),
1048     DEFINE_PROP_TPMBE("tpmdev", TPMState, be_driver),
1049     DEFINE_PROP_END_OF_LIST(),
1050 };
1051 
1052 static void tpm_tis_realizefn(DeviceState *dev, Error **errp)
1053 {
1054     TPMState *s = TPM(dev);
1055 
1056     if (!tpm_find()) {
1057         error_setg(errp, "at most one TPM device is permitted");
1058         return;
1059     }
1060 
1061     if (!s->be_driver) {
1062         error_setg(errp, "'tpmdev' property is required");
1063         return;
1064     }
1065     if (s->irq_num > 15) {
1066         error_setg(errp, "IRQ %d is outside valid range of 0 to 15",
1067                    s->irq_num);
1068         return;
1069     }
1070 
1071     isa_init_irq(&s->busdev, &s->irq, s->irq_num);
1072 
1073     memory_region_add_subregion(isa_address_space(ISA_DEVICE(dev)),
1074                                 TPM_TIS_ADDR_BASE, &s->mmio);
1075 }
1076 
1077 static void tpm_tis_initfn(Object *obj)
1078 {
1079     TPMState *s = TPM(obj);
1080 
1081     memory_region_init_io(&s->mmio, OBJECT(s), &tpm_tis_memory_ops,
1082                           s, "tpm-tis-mmio",
1083                           TPM_TIS_NUM_LOCALITIES << TPM_TIS_LOCALITY_SHIFT);
1084 }
1085 
1086 static void tpm_tis_class_init(ObjectClass *klass, void *data)
1087 {
1088     DeviceClass *dc = DEVICE_CLASS(klass);
1089     TPMIfClass *tc = TPM_IF_CLASS(klass);
1090 
1091     dc->realize = tpm_tis_realizefn;
1092     dc->props = tpm_tis_properties;
1093     dc->reset = tpm_tis_reset;
1094     dc->vmsd  = &vmstate_tpm_tis;
1095     tc->model = TPM_MODEL_TPM_TIS;
1096     tc->get_version = tpm_tis_get_tpm_version;
1097     tc->request_completed = tpm_tis_request_completed;
1098 }
1099 
1100 static const TypeInfo tpm_tis_info = {
1101     .name = TYPE_TPM_TIS,
1102     .parent = TYPE_ISA_DEVICE,
1103     .instance_size = sizeof(TPMState),
1104     .instance_init = tpm_tis_initfn,
1105     .class_init  = tpm_tis_class_init,
1106     .interfaces = (InterfaceInfo[]) {
1107         { TYPE_TPM_IF },
1108         { }
1109     }
1110 };
1111 
1112 static void tpm_tis_register(void)
1113 {
1114     type_register_static(&tpm_tis_info);
1115 }
1116 
1117 type_init(tpm_tis_register)
1118