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14#include <linux/acpi.h>
15#include <linux/highmem.h>
16#include <linux/rculist.h>
17#include <linux/module.h>
18#include <linux/pm_runtime.h>
19#ifdef CONFIG_ARM64
20#include <linux/arm-smccc.h>
21#endif
22#include "tpm.h"
23
24#define ACPI_SIG_TPM2 "TPM2"
25#define TPM_CRB_MAX_RESOURCES 3
26
27static const guid_t crb_acpi_start_guid =
28 GUID_INIT(0x6BBF6CAB, 0x5463, 0x4714,
29 0xB7, 0xCD, 0xF0, 0x20, 0x3C, 0x03, 0x68, 0xD4);
30
31enum crb_defaults {
32 CRB_ACPI_START_REVISION_ID = 1,
33 CRB_ACPI_START_INDEX = 1,
34};
35
36enum crb_loc_ctrl {
37 CRB_LOC_CTRL_REQUEST_ACCESS = BIT(0),
38 CRB_LOC_CTRL_RELINQUISH = BIT(1),
39};
40
41enum crb_loc_state {
42 CRB_LOC_STATE_LOC_ASSIGNED = BIT(1),
43 CRB_LOC_STATE_TPM_REG_VALID_STS = BIT(7),
44};
45
46enum crb_ctrl_req {
47 CRB_CTRL_REQ_CMD_READY = BIT(0),
48 CRB_CTRL_REQ_GO_IDLE = BIT(1),
49};
50
51enum crb_ctrl_sts {
52 CRB_CTRL_STS_ERROR = BIT(0),
53 CRB_CTRL_STS_TPM_IDLE = BIT(1),
54};
55
56enum crb_start {
57 CRB_START_INVOKE = BIT(0),
58};
59
60enum crb_cancel {
61 CRB_CANCEL_INVOKE = BIT(0),
62};
63
64struct crb_regs_head {
65 u32 loc_state;
66 u32 reserved1;
67 u32 loc_ctrl;
68 u32 loc_sts;
69 u8 reserved2[32];
70 u64 intf_id;
71 u64 ctrl_ext;
72} __packed;
73
74struct crb_regs_tail {
75 u32 ctrl_req;
76 u32 ctrl_sts;
77 u32 ctrl_cancel;
78 u32 ctrl_start;
79 u32 ctrl_int_enable;
80 u32 ctrl_int_sts;
81 u32 ctrl_cmd_size;
82 u32 ctrl_cmd_pa_low;
83 u32 ctrl_cmd_pa_high;
84 u32 ctrl_rsp_size;
85 u64 ctrl_rsp_pa;
86} __packed;
87
88enum crb_status {
89 CRB_DRV_STS_COMPLETE = BIT(0),
90};
91
92struct crb_priv {
93 u32 sm;
94 const char *hid;
95 struct crb_regs_head __iomem *regs_h;
96 struct crb_regs_tail __iomem *regs_t;
97 u8 __iomem *cmd;
98 u8 __iomem *rsp;
99 u32 cmd_size;
100 u32 smc_func_id;
101};
102
103struct tpm2_crb_smc {
104 u32 interrupt;
105 u8 interrupt_flags;
106 u8 op_flags;
107 u16 reserved2;
108 u32 smc_func_id;
109};
110
111static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value,
112 unsigned long timeout)
113{
114 ktime_t start;
115 ktime_t stop;
116
117 start = ktime_get();
118 stop = ktime_add(start, ms_to_ktime(timeout));
119
120 do {
121 if ((ioread32(reg) & mask) == value)
122 return true;
123
124 usleep_range(50, 100);
125 } while (ktime_before(ktime_get(), stop));
126
127 return ((ioread32(reg) & mask) == value);
128}
129
130
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137
138
139
140
141
142
143
144
145
146static int __crb_go_idle(struct device *dev, struct crb_priv *priv)
147{
148 if ((priv->sm == ACPI_TPM2_START_METHOD) ||
149 (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
150 (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC))
151 return 0;
152
153 iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req);
154
155 if (!crb_wait_for_reg_32(&priv->regs_t->ctrl_req,
156 CRB_CTRL_REQ_GO_IDLE,
157 0,
158 TPM2_TIMEOUT_C)) {
159 dev_warn(dev, "goIdle timed out\n");
160 return -ETIME;
161 }
162
163 return 0;
164}
165
166static int crb_go_idle(struct tpm_chip *chip)
167{
168 struct device *dev = &chip->dev;
169 struct crb_priv *priv = dev_get_drvdata(dev);
170
171 return __crb_go_idle(dev, priv);
172}
173
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181
182
183
184
185
186
187
188
189static int __crb_cmd_ready(struct device *dev, struct crb_priv *priv)
190{
191 if ((priv->sm == ACPI_TPM2_START_METHOD) ||
192 (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) ||
193 (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC))
194 return 0;
195
196 iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->regs_t->ctrl_req);
197 if (!crb_wait_for_reg_32(&priv->regs_t->ctrl_req,
198 CRB_CTRL_REQ_CMD_READY ,
199 0,
200 TPM2_TIMEOUT_C)) {
201 dev_warn(dev, "cmdReady timed out\n");
202 return -ETIME;
203 }
204
205 return 0;
206}
207
208static int crb_cmd_ready(struct tpm_chip *chip)
209{
210 struct device *dev = &chip->dev;
211 struct crb_priv *priv = dev_get_drvdata(dev);
212
213 return __crb_cmd_ready(dev, priv);
214}
215
216static int __crb_request_locality(struct device *dev,
217 struct crb_priv *priv, int loc)
218{
219 u32 value = CRB_LOC_STATE_LOC_ASSIGNED |
220 CRB_LOC_STATE_TPM_REG_VALID_STS;
221
222 if (!priv->regs_h)
223 return 0;
224
225 iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h->loc_ctrl);
226 if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, value, value,
227 TPM2_TIMEOUT_C)) {
228 dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed out\n");
229 return -ETIME;
230 }
231
232 return 0;
233}
234
235static int crb_request_locality(struct tpm_chip *chip, int loc)
236{
237 struct crb_priv *priv = dev_get_drvdata(&chip->dev);
238
239 return __crb_request_locality(&chip->dev, priv, loc);
240}
241
242static int __crb_relinquish_locality(struct device *dev,
243 struct crb_priv *priv, int loc)
244{
245 u32 mask = CRB_LOC_STATE_LOC_ASSIGNED |
246 CRB_LOC_STATE_TPM_REG_VALID_STS;
247 u32 value = CRB_LOC_STATE_TPM_REG_VALID_STS;
248
249 if (!priv->regs_h)
250 return 0;
251
252 iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl);
253 if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, mask, value,
254 TPM2_TIMEOUT_C)) {
255 dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed out\n");
256 return -ETIME;
257 }
258
259 return 0;
260}
261
262static int crb_relinquish_locality(struct tpm_chip *chip, int loc)
263{
264 struct crb_priv *priv = dev_get_drvdata(&chip->dev);
265
266 return __crb_relinquish_locality(&chip->dev, priv, loc);
267}
268
269static u8 crb_status(struct tpm_chip *chip)
270{
271 struct crb_priv *priv = dev_get_drvdata(&chip->dev);
272 u8 sts = 0;
273
274 if ((ioread32(&priv->regs_t->ctrl_start) & CRB_START_INVOKE) !=
275 CRB_START_INVOKE)
276 sts |= CRB_DRV_STS_COMPLETE;
277
278 return sts;
279}
280
281static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count)
282{
283 struct crb_priv *priv = dev_get_drvdata(&chip->dev);
284 unsigned int expected;
285
286
287
288
289 if (count < TPM_HEADER_SIZE)
290 return -EIO;
291
292
293
294
295 if (ioread32(&priv->regs_t->ctrl_sts) & CRB_CTRL_STS_ERROR)
296 return -EIO;
297
298
299
300
301
302 memcpy_fromio(buf, priv->rsp, 8);
303
304 expected = be32_to_cpup((__be32 *)&buf[2]);
305 if (expected > count || expected < TPM_HEADER_SIZE)
306 return -EIO;
307
308 memcpy_fromio(&buf[8], &priv->rsp[8], expected - 8);
309
310 return expected;
311}
312
313static int crb_do_acpi_start(struct tpm_chip *chip)
314{
315 union acpi_object *obj;
316 int rc;
317
318 obj = acpi_evaluate_dsm(chip->acpi_dev_handle,
319 &crb_acpi_start_guid,
320 CRB_ACPI_START_REVISION_ID,
321 CRB_ACPI_START_INDEX,
322 NULL);
323 if (!obj)
324 return -ENXIO;
325 rc = obj->integer.value == 0 ? 0 : -ENXIO;
326 ACPI_FREE(obj);
327 return rc;
328}
329
330#ifdef CONFIG_ARM64
331
332
333
334
335
336static int tpm_crb_smc_start(struct device *dev, unsigned long func_id)
337{
338 struct arm_smccc_res res;
339
340 arm_smccc_smc(func_id, 0, 0, 0, 0, 0, 0, 0, &res);
341 if (res.a0 != 0) {
342 dev_err(dev,
343 FW_BUG "tpm_crb_smc_start() returns res.a0 = 0x%lx\n",
344 res.a0);
345 return -EIO;
346 }
347
348 return 0;
349}
350#else
351static int tpm_crb_smc_start(struct device *dev, unsigned long func_id)
352{
353 dev_err(dev, FW_BUG "tpm_crb: incorrect start method\n");
354 return -EINVAL;
355}
356#endif
357
358static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
359{
360 struct crb_priv *priv = dev_get_drvdata(&chip->dev);
361 int rc = 0;
362
363
364
365
366 iowrite32(0, &priv->regs_t->ctrl_cancel);
367
368 if (len > priv->cmd_size) {
369 dev_err(&chip->dev, "invalid command count value %zd %d\n",
370 len, priv->cmd_size);
371 return -E2BIG;
372 }
373
374 memcpy_toio(priv->cmd, buf, len);
375
376
377 wmb();
378
379
380
381
382
383 if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) ||
384 (priv->sm == ACPI_TPM2_MEMORY_MAPPED) ||
385 (!strcmp(priv->hid, "MSFT0101")))
386 iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
387
388 if ((priv->sm == ACPI_TPM2_START_METHOD) ||
389 (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD))
390 rc = crb_do_acpi_start(chip);
391
392 if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) {
393 iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
394 rc = tpm_crb_smc_start(&chip->dev, priv->smc_func_id);
395 }
396
397 return rc;
398}
399
400static void crb_cancel(struct tpm_chip *chip)
401{
402 struct crb_priv *priv = dev_get_drvdata(&chip->dev);
403
404 iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel);
405
406 if (((priv->sm == ACPI_TPM2_START_METHOD) ||
407 (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)) &&
408 crb_do_acpi_start(chip))
409 dev_err(&chip->dev, "ACPI Start failed\n");
410}
411
412static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
413{
414 struct crb_priv *priv = dev_get_drvdata(&chip->dev);
415 u32 cancel = ioread32(&priv->regs_t->ctrl_cancel);
416
417 return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE;
418}
419
420static const struct tpm_class_ops tpm_crb = {
421 .flags = TPM_OPS_AUTO_STARTUP,
422 .status = crb_status,
423 .recv = crb_recv,
424 .send = crb_send,
425 .cancel = crb_cancel,
426 .req_canceled = crb_req_canceled,
427 .go_idle = crb_go_idle,
428 .cmd_ready = crb_cmd_ready,
429 .request_locality = crb_request_locality,
430 .relinquish_locality = crb_relinquish_locality,
431 .req_complete_mask = CRB_DRV_STS_COMPLETE,
432 .req_complete_val = CRB_DRV_STS_COMPLETE,
433};
434
435static int crb_check_resource(struct acpi_resource *ares, void *data)
436{
437 struct resource *iores_array = data;
438 struct resource_win win;
439 struct resource *res = &(win.res);
440 int i;
441
442 if (acpi_dev_resource_memory(ares, res) ||
443 acpi_dev_resource_address_space(ares, &win)) {
444 for (i = 0; i < TPM_CRB_MAX_RESOURCES + 1; ++i) {
445 if (resource_type(iores_array + i) != IORESOURCE_MEM) {
446 iores_array[i] = *res;
447 iores_array[i].name = NULL;
448 break;
449 }
450 }
451 }
452
453 return 1;
454}
455
456static void __iomem *crb_map_res(struct device *dev, struct resource *iores,
457 void __iomem **iobase_ptr, u64 start, u32 size)
458{
459 struct resource new_res = {
460 .start = start,
461 .end = start + size - 1,
462 .flags = IORESOURCE_MEM,
463 };
464
465
466 if (start != new_res.start)
467 return (void __iomem *) ERR_PTR(-EINVAL);
468
469 if (!iores)
470 return devm_ioremap_resource(dev, &new_res);
471
472 if (!*iobase_ptr) {
473 *iobase_ptr = devm_ioremap_resource(dev, iores);
474 if (IS_ERR(*iobase_ptr))
475 return *iobase_ptr;
476 }
477
478 return *iobase_ptr + (new_res.start - iores->start);
479}
480
481
482
483
484
485
486static u64 crb_fixup_cmd_size(struct device *dev, struct resource *io_res,
487 u64 start, u64 size)
488{
489 if (io_res->start > start || io_res->end < start)
490 return size;
491
492 if (start + size - 1 <= io_res->end)
493 return size;
494
495 dev_err(dev,
496 FW_BUG "ACPI region does not cover the entire command/response buffer. %pr vs %llx %llx\n",
497 io_res, start, size);
498
499 return io_res->end - start + 1;
500}
501
502static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
503 struct acpi_table_tpm2 *buf)
504{
505 struct list_head acpi_resource_list;
506 struct resource iores_array[TPM_CRB_MAX_RESOURCES + 1] = { {0} };
507 void __iomem *iobase_array[TPM_CRB_MAX_RESOURCES] = {NULL};
508 struct device *dev = &device->dev;
509 struct resource *iores;
510 void __iomem **iobase_ptr;
511 int i;
512 u32 pa_high, pa_low;
513 u64 cmd_pa;
514 u32 cmd_size;
515 __le64 __rsp_pa;
516 u64 rsp_pa;
517 u32 rsp_size;
518 int ret;
519
520 INIT_LIST_HEAD(&acpi_resource_list);
521 ret = acpi_dev_get_resources(device, &acpi_resource_list,
522 crb_check_resource, iores_array);
523 if (ret < 0)
524 return ret;
525 acpi_dev_free_resource_list(&acpi_resource_list);
526
527 if (resource_type(iores_array) != IORESOURCE_MEM) {
528 dev_err(dev, FW_BUG "TPM2 ACPI table does not define a memory resource\n");
529 return -EINVAL;
530 } else if (resource_type(iores_array + TPM_CRB_MAX_RESOURCES) ==
531 IORESOURCE_MEM) {
532 dev_warn(dev, "TPM2 ACPI table defines too many memory resources\n");
533 memset(iores_array + TPM_CRB_MAX_RESOURCES,
534 0, sizeof(*iores_array));
535 iores_array[TPM_CRB_MAX_RESOURCES].flags = 0;
536 }
537
538 iores = NULL;
539 iobase_ptr = NULL;
540 for (i = 0; resource_type(iores_array + i) == IORESOURCE_MEM; ++i) {
541 if (buf->control_address >= iores_array[i].start &&
542 buf->control_address + sizeof(struct crb_regs_tail) - 1 <=
543 iores_array[i].end) {
544 iores = iores_array + i;
545 iobase_ptr = iobase_array + i;
546 break;
547 }
548 }
549
550 priv->regs_t = crb_map_res(dev, iores, iobase_ptr, buf->control_address,
551 sizeof(struct crb_regs_tail));
552
553 if (IS_ERR(priv->regs_t))
554 return PTR_ERR(priv->regs_t);
555
556
557
558
559
560 if ((priv->sm == ACPI_TPM2_COMMAND_BUFFER) ||
561 (priv->sm == ACPI_TPM2_MEMORY_MAPPED)) {
562 if (iores &&
563 buf->control_address == iores->start +
564 sizeof(*priv->regs_h))
565 priv->regs_h = *iobase_ptr;
566 else
567 dev_warn(dev, FW_BUG "Bad ACPI memory layout");
568 }
569
570 ret = __crb_request_locality(dev, priv, 0);
571 if (ret)
572 return ret;
573
574
575
576
577
578 ret = __crb_cmd_ready(dev, priv);
579 if (ret)
580 goto out_relinquish_locality;
581
582 pa_high = ioread32(&priv->regs_t->ctrl_cmd_pa_high);
583 pa_low = ioread32(&priv->regs_t->ctrl_cmd_pa_low);
584 cmd_pa = ((u64)pa_high << 32) | pa_low;
585 cmd_size = ioread32(&priv->regs_t->ctrl_cmd_size);
586
587 iores = NULL;
588 iobase_ptr = NULL;
589 for (i = 0; iores_array[i].end; ++i) {
590 if (cmd_pa >= iores_array[i].start &&
591 cmd_pa <= iores_array[i].end) {
592 iores = iores_array + i;
593 iobase_ptr = iobase_array + i;
594 break;
595 }
596 }
597
598 if (iores)
599 cmd_size = crb_fixup_cmd_size(dev, iores, cmd_pa, cmd_size);
600
601 dev_dbg(dev, "cmd_hi = %X cmd_low = %X cmd_size %X\n",
602 pa_high, pa_low, cmd_size);
603
604 priv->cmd = crb_map_res(dev, iores, iobase_ptr, cmd_pa, cmd_size);
605 if (IS_ERR(priv->cmd)) {
606 ret = PTR_ERR(priv->cmd);
607 goto out;
608 }
609
610 memcpy_fromio(&__rsp_pa, &priv->regs_t->ctrl_rsp_pa, 8);
611 rsp_pa = le64_to_cpu(__rsp_pa);
612 rsp_size = ioread32(&priv->regs_t->ctrl_rsp_size);
613
614 iores = NULL;
615 iobase_ptr = NULL;
616 for (i = 0; resource_type(iores_array + i) == IORESOURCE_MEM; ++i) {
617 if (rsp_pa >= iores_array[i].start &&
618 rsp_pa <= iores_array[i].end) {
619 iores = iores_array + i;
620 iobase_ptr = iobase_array + i;
621 break;
622 }
623 }
624
625 if (iores)
626 rsp_size = crb_fixup_cmd_size(dev, iores, rsp_pa, rsp_size);
627
628 if (cmd_pa != rsp_pa) {
629 priv->rsp = crb_map_res(dev, iores, iobase_ptr,
630 rsp_pa, rsp_size);
631 ret = PTR_ERR_OR_ZERO(priv->rsp);
632 goto out;
633 }
634
635
636
637
638 if (cmd_size != rsp_size) {
639 dev_err(dev, FW_BUG "overlapping command and response buffer sizes are not identical");
640 ret = -EINVAL;
641 goto out;
642 }
643
644 priv->rsp = priv->cmd;
645
646out:
647 if (!ret)
648 priv->cmd_size = cmd_size;
649
650 __crb_go_idle(dev, priv);
651
652out_relinquish_locality:
653
654 __crb_relinquish_locality(dev, priv, 0);
655
656 return ret;
657}
658
659static int crb_acpi_add(struct acpi_device *device)
660{
661 struct acpi_table_tpm2 *buf;
662 struct crb_priv *priv;
663 struct tpm_chip *chip;
664 struct device *dev = &device->dev;
665 struct tpm2_crb_smc *crb_smc;
666 acpi_status status;
667 u32 sm;
668 int rc;
669
670 status = acpi_get_table(ACPI_SIG_TPM2, 1,
671 (struct acpi_table_header **) &buf);
672 if (ACPI_FAILURE(status) || buf->header.length < sizeof(*buf)) {
673 dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n");
674 return -EINVAL;
675 }
676
677
678 sm = buf->start_method;
679 if (sm == ACPI_TPM2_MEMORY_MAPPED)
680 return -ENODEV;
681
682 priv = devm_kzalloc(dev, sizeof(struct crb_priv), GFP_KERNEL);
683 if (!priv)
684 return -ENOMEM;
685
686 if (sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) {
687 if (buf->header.length < (sizeof(*buf) + sizeof(*crb_smc))) {
688 dev_err(dev,
689 FW_BUG "TPM2 ACPI table has wrong size %u for start method type %d\n",
690 buf->header.length,
691 ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC);
692 return -EINVAL;
693 }
694 crb_smc = ACPI_ADD_PTR(struct tpm2_crb_smc, buf, sizeof(*buf));
695 priv->smc_func_id = crb_smc->smc_func_id;
696 }
697
698 priv->sm = sm;
699 priv->hid = acpi_device_hid(device);
700
701 rc = crb_map_io(device, priv, buf);
702 if (rc)
703 return rc;
704
705 chip = tpmm_chip_alloc(dev, &tpm_crb);
706 if (IS_ERR(chip))
707 return PTR_ERR(chip);
708
709 dev_set_drvdata(&chip->dev, priv);
710 chip->acpi_dev_handle = device->handle;
711 chip->flags = TPM_CHIP_FLAG_TPM2;
712
713 return tpm_chip_register(chip);
714}
715
716static int crb_acpi_remove(struct acpi_device *device)
717{
718 struct device *dev = &device->dev;
719 struct tpm_chip *chip = dev_get_drvdata(dev);
720
721 tpm_chip_unregister(chip);
722
723 return 0;
724}
725
726static const struct dev_pm_ops crb_pm = {
727 SET_SYSTEM_SLEEP_PM_OPS(tpm_pm_suspend, tpm_pm_resume)
728};
729
730static const struct acpi_device_id crb_device_ids[] = {
731 {"MSFT0101", 0},
732 {"", 0},
733};
734MODULE_DEVICE_TABLE(acpi, crb_device_ids);
735
736static struct acpi_driver crb_acpi_driver = {
737 .name = "tpm_crb",
738 .ids = crb_device_ids,
739 .ops = {
740 .add = crb_acpi_add,
741 .remove = crb_acpi_remove,
742 },
743 .drv = {
744 .pm = &crb_pm,
745 },
746};
747
748module_acpi_driver(crb_acpi_driver);
749MODULE_AUTHOR("Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>");
750MODULE_DESCRIPTION("TPM2 Driver");
751MODULE_VERSION("0.1");
752MODULE_LICENSE("GPL");
753