1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014 Intel Corporation
4  *
5  * Authors:
6  * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
7  *
8  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
9  *
10  * This device driver implements the TPM interface as defined in
11  * the TCG CRB 2.0 TPM specification.
12  */
13 
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_crb_ffa.h"
23 #include "tpm.h"
24 
25 #define ACPI_SIG_TPM2 "TPM2"
26 #define TPM_CRB_MAX_RESOURCES 3
27 
28 static const guid_t crb_acpi_start_guid =
29 	GUID_INIT(0x6BBF6CAB, 0x5463, 0x4714,
30 		  0xB7, 0xCD, 0xF0, 0x20, 0x3C, 0x03, 0x68, 0xD4);
31 
32 enum crb_defaults {
33 	CRB_ACPI_START_REVISION_ID = 1,
34 	CRB_ACPI_START_INDEX = 1,
35 };
36 
37 enum crb_loc_ctrl {
38 	CRB_LOC_CTRL_REQUEST_ACCESS	= BIT(0),
39 	CRB_LOC_CTRL_RELINQUISH		= BIT(1),
40 };
41 
42 enum crb_loc_state {
43 	CRB_LOC_STATE_LOC_ASSIGNED	= BIT(1),
44 	CRB_LOC_STATE_TPM_REG_VALID_STS	= BIT(7),
45 };
46 
47 enum crb_ctrl_req {
48 	CRB_CTRL_REQ_CMD_READY	= BIT(0),
49 	CRB_CTRL_REQ_GO_IDLE	= BIT(1),
50 };
51 
52 enum crb_ctrl_sts {
53 	CRB_CTRL_STS_ERROR	= BIT(0),
54 	CRB_CTRL_STS_TPM_IDLE	= BIT(1),
55 };
56 
57 enum crb_start {
58 	CRB_START_INVOKE	= BIT(0),
59 };
60 
61 enum crb_cancel {
62 	CRB_CANCEL_INVOKE	= BIT(0),
63 };
64 
65 struct crb_regs_head {
66 	u32 loc_state;
67 	u32 reserved1;
68 	u32 loc_ctrl;
69 	u32 loc_sts;
70 	u8 reserved2[32];
71 	u64 intf_id;
72 	u64 ctrl_ext;
73 } __packed;
74 
75 struct crb_regs_tail {
76 	u32 ctrl_req;
77 	u32 ctrl_sts;
78 	u32 ctrl_cancel;
79 	u32 ctrl_start;
80 	u32 ctrl_int_enable;
81 	u32 ctrl_int_sts;
82 	u32 ctrl_cmd_size;
83 	u32 ctrl_cmd_pa_low;
84 	u32 ctrl_cmd_pa_high;
85 	u32 ctrl_rsp_size;
86 	u64 ctrl_rsp_pa;
87 } __packed;
88 
89 enum crb_status {
90 	CRB_DRV_STS_COMPLETE	= BIT(0),
91 };
92 
93 struct crb_priv {
94 	u32 sm;
95 	const char *hid;
96 	struct crb_regs_head __iomem *regs_h;
97 	struct crb_regs_tail __iomem *regs_t;
98 	u8 __iomem *cmd;
99 	u8 __iomem *rsp;
100 	u32 cmd_size;
101 	u32 smc_func_id;
102 	u32 __iomem *pluton_start_addr;
103 	u32 __iomem *pluton_reply_addr;
104 	u8 ffa_flags;
105 	u8 ffa_attributes;
106 };
107 
108 struct tpm2_crb_smc {
109 	u32 interrupt;
110 	u8 interrupt_flags;
111 	u8 op_flags;
112 	u16 reserved2;
113 	u32 smc_func_id;
114 };
115 
116 /* CRB over FFA start method parameters in TCG2 ACPI table */
117 struct tpm2_crb_ffa {
118 	u8 flags;
119 	u8 attributes;
120 	u16 partition_id;
121 	u8 reserved[8];
122 };
123 
124 struct tpm2_crb_pluton {
125 	u64 start_addr;
126 	u64 reply_addr;
127 };
128 
129 /*
130  * Returns true if the start method supports idle.
131  */
tpm_crb_has_idle(u32 start_method)132 static inline bool tpm_crb_has_idle(u32 start_method)
133 {
134 	return !(start_method == ACPI_TPM2_START_METHOD ||
135 	       start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD ||
136 	       start_method == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC ||
137 	       start_method == ACPI_TPM2_CRB_WITH_ARM_FFA);
138 }
139 
crb_wait_for_reg_32(u32 __iomem * reg,u32 mask,u32 value,unsigned long timeout)140 static bool crb_wait_for_reg_32(u32 __iomem *reg, u32 mask, u32 value,
141 				unsigned long timeout)
142 {
143 	ktime_t start;
144 	ktime_t stop;
145 
146 	start = ktime_get();
147 	stop = ktime_add(start, ms_to_ktime(timeout));
148 
149 	do {
150 		if ((ioread32(reg) & mask) == value)
151 			return true;
152 
153 		usleep_range(50, 100);
154 	} while (ktime_before(ktime_get(), stop));
155 
156 	return ((ioread32(reg) & mask) == value);
157 }
158 
crb_try_pluton_doorbell(struct crb_priv * priv,bool wait_for_complete)159 static int crb_try_pluton_doorbell(struct crb_priv *priv, bool wait_for_complete)
160 {
161 	if (priv->sm != ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON)
162 		return 0;
163 
164 	if (!crb_wait_for_reg_32(priv->pluton_reply_addr, ~0, 1, TPM2_TIMEOUT_C))
165 		return -ETIME;
166 
167 	iowrite32(1, priv->pluton_start_addr);
168 	if (wait_for_complete == false)
169 		return 0;
170 
171 	if (!crb_wait_for_reg_32(priv->pluton_start_addr,
172 				 0xffffffff, 0, 200))
173 		return -ETIME;
174 
175 	return 0;
176 }
177 
178 /**
179  * __crb_go_idle - request tpm crb device to go the idle state
180  *
181  * @dev:  crb device
182  * @priv: crb private data
183  *
184  * Write CRB_CTRL_REQ_GO_IDLE to TPM_CRB_CTRL_REQ
185  * The device should respond within TIMEOUT_C by clearing the bit.
186  * Anyhow, we do not wait here as a consequent CMD_READY request
187  * will be handled correctly even if idle was not completed.
188  *
189  * The function does nothing for devices with ACPI-start method
190  * or SMC-start method.
191  *
192  * Return: 0 always
193  */
__crb_go_idle(struct device * dev,struct crb_priv * priv)194 static int __crb_go_idle(struct device *dev, struct crb_priv *priv)
195 {
196 	int rc;
197 
198 	if (!tpm_crb_has_idle(priv->sm))
199 		return 0;
200 
201 	iowrite32(CRB_CTRL_REQ_GO_IDLE, &priv->regs_t->ctrl_req);
202 
203 	rc = crb_try_pluton_doorbell(priv, true);
204 	if (rc)
205 		return rc;
206 
207 	if (!crb_wait_for_reg_32(&priv->regs_t->ctrl_req,
208 				 CRB_CTRL_REQ_GO_IDLE/* mask */,
209 				 0, /* value */
210 				 TPM2_TIMEOUT_C)) {
211 		dev_warn(dev, "goIdle timed out\n");
212 		return -ETIME;
213 	}
214 
215 	return 0;
216 }
217 
crb_go_idle(struct tpm_chip * chip)218 static int crb_go_idle(struct tpm_chip *chip)
219 {
220 	struct device *dev = &chip->dev;
221 	struct crb_priv *priv = dev_get_drvdata(dev);
222 
223 	return __crb_go_idle(dev, priv);
224 }
225 
226 /**
227  * __crb_cmd_ready - request tpm crb device to enter ready state
228  *
229  * @dev:  crb device
230  * @priv: crb private data
231  *
232  * Write CRB_CTRL_REQ_CMD_READY to TPM_CRB_CTRL_REQ
233  * and poll till the device acknowledge it by clearing the bit.
234  * The device should respond within TIMEOUT_C.
235  *
236  * The function does nothing for devices with ACPI-start method
237  * or SMC-start method.
238  *
239  * Return: 0 on success -ETIME on timeout;
240  */
__crb_cmd_ready(struct device * dev,struct crb_priv * priv)241 static int __crb_cmd_ready(struct device *dev, struct crb_priv *priv)
242 {
243 	int rc;
244 
245 	if (!tpm_crb_has_idle(priv->sm))
246 		return 0;
247 
248 	iowrite32(CRB_CTRL_REQ_CMD_READY, &priv->regs_t->ctrl_req);
249 
250 	rc = crb_try_pluton_doorbell(priv, true);
251 	if (rc)
252 		return rc;
253 
254 	if (!crb_wait_for_reg_32(&priv->regs_t->ctrl_req,
255 				 CRB_CTRL_REQ_CMD_READY /* mask */,
256 				 0, /* value */
257 				 TPM2_TIMEOUT_C)) {
258 		dev_warn(dev, "cmdReady timed out\n");
259 		return -ETIME;
260 	}
261 
262 	return 0;
263 }
264 
crb_cmd_ready(struct tpm_chip * chip)265 static int crb_cmd_ready(struct tpm_chip *chip)
266 {
267 	struct device *dev = &chip->dev;
268 	struct crb_priv *priv = dev_get_drvdata(dev);
269 
270 	return __crb_cmd_ready(dev, priv);
271 }
272 
__crb_request_locality(struct device * dev,struct crb_priv * priv,int loc)273 static int __crb_request_locality(struct device *dev,
274 				  struct crb_priv *priv, int loc)
275 {
276 	u32 value = CRB_LOC_STATE_LOC_ASSIGNED | CRB_LOC_STATE_TPM_REG_VALID_STS;
277 	int rc;
278 
279 	if (!priv->regs_h)
280 		return 0;
281 
282 	iowrite32(CRB_LOC_CTRL_REQUEST_ACCESS, &priv->regs_h->loc_ctrl);
283 
284 	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
285 		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_LOCALITY_REQUEST, loc);
286 		if (rc)
287 			return rc;
288 	}
289 
290 	if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, value, value,
291 				 TPM2_TIMEOUT_C)) {
292 		dev_warn(dev, "TPM_LOC_STATE_x.requestAccess timed out\n");
293 		return -ETIME;
294 	}
295 
296 	return 0;
297 }
298 
crb_request_locality(struct tpm_chip * chip,int loc)299 static int crb_request_locality(struct tpm_chip *chip, int loc)
300 {
301 	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
302 
303 	return __crb_request_locality(&chip->dev, priv, loc);
304 }
305 
__crb_relinquish_locality(struct device * dev,struct crb_priv * priv,int loc)306 static int __crb_relinquish_locality(struct device *dev,
307 				     struct crb_priv *priv, int loc)
308 {
309 	u32 mask = CRB_LOC_STATE_LOC_ASSIGNED | CRB_LOC_STATE_TPM_REG_VALID_STS;
310 	u32 value = CRB_LOC_STATE_TPM_REG_VALID_STS;
311 	int rc;
312 
313 	if (!priv->regs_h)
314 		return 0;
315 
316 	iowrite32(CRB_LOC_CTRL_RELINQUISH, &priv->regs_h->loc_ctrl);
317 
318 	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
319 		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_LOCALITY_REQUEST, loc);
320 		if (rc)
321 			return rc;
322 	}
323 
324 	if (!crb_wait_for_reg_32(&priv->regs_h->loc_state, mask, value,
325 				 TPM2_TIMEOUT_C)) {
326 		dev_warn(dev, "TPM_LOC_STATE_x.Relinquish timed out\n");
327 		return -ETIME;
328 	}
329 
330 	return 0;
331 }
332 
crb_relinquish_locality(struct tpm_chip * chip,int loc)333 static int crb_relinquish_locality(struct tpm_chip *chip, int loc)
334 {
335 	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
336 
337 	return __crb_relinquish_locality(&chip->dev, priv, loc);
338 }
339 
crb_status(struct tpm_chip * chip)340 static u8 crb_status(struct tpm_chip *chip)
341 {
342 	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
343 	u8 sts = 0;
344 
345 	if ((ioread32(&priv->regs_t->ctrl_start) & CRB_START_INVOKE) !=
346 	    CRB_START_INVOKE)
347 		sts |= CRB_DRV_STS_COMPLETE;
348 
349 	return sts;
350 }
351 
crb_recv(struct tpm_chip * chip,u8 * buf,size_t count)352 static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count)
353 {
354 	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
355 	unsigned int expected;
356 
357 	/* A sanity check that the upper layer wants to get at least the header
358 	 * as that is the minimum size for any TPM response.
359 	 */
360 	if (count < TPM_HEADER_SIZE)
361 		return -EIO;
362 
363 	/* If this bit is set, according to the spec, the TPM is in
364 	 * unrecoverable condition.
365 	 */
366 	if (ioread32(&priv->regs_t->ctrl_sts) & CRB_CTRL_STS_ERROR)
367 		return -EIO;
368 
369 	/* Read the first 8 bytes in order to get the length of the response.
370 	 * We read exactly a quad word in order to make sure that the remaining
371 	 * reads will be aligned.
372 	 */
373 	memcpy_fromio(buf, priv->rsp, 8);
374 
375 	expected = be32_to_cpup((__be32 *)&buf[2]);
376 	if (expected > count || expected < TPM_HEADER_SIZE)
377 		return -EIO;
378 
379 	memcpy_fromio(&buf[8], &priv->rsp[8], expected - 8);
380 
381 	return expected;
382 }
383 
crb_do_acpi_start(struct tpm_chip * chip)384 static int crb_do_acpi_start(struct tpm_chip *chip)
385 {
386 	union acpi_object *obj;
387 	int rc;
388 
389 	obj = acpi_evaluate_dsm(chip->acpi_dev_handle,
390 				&crb_acpi_start_guid,
391 				CRB_ACPI_START_REVISION_ID,
392 				CRB_ACPI_START_INDEX,
393 				NULL);
394 	if (!obj)
395 		return -ENXIO;
396 	rc = obj->integer.value == 0 ? 0 : -ENXIO;
397 	ACPI_FREE(obj);
398 	return rc;
399 }
400 
401 #ifdef CONFIG_ARM64
402 /*
403  * This is a TPM Command Response Buffer start method that invokes a
404  * Secure Monitor Call to requrest the firmware to execute or cancel
405  * a TPM 2.0 command.
406  */
tpm_crb_smc_start(struct device * dev,unsigned long func_id)407 static int tpm_crb_smc_start(struct device *dev, unsigned long func_id)
408 {
409 	struct arm_smccc_res res;
410 
411 	arm_smccc_smc(func_id, 0, 0, 0, 0, 0, 0, 0, &res);
412 	if (res.a0 != 0) {
413 		dev_err(dev,
414 			FW_BUG "tpm_crb_smc_start() returns res.a0 = 0x%lx\n",
415 			res.a0);
416 		return -EIO;
417 	}
418 
419 	return 0;
420 }
421 #else
tpm_crb_smc_start(struct device * dev,unsigned long func_id)422 static int tpm_crb_smc_start(struct device *dev, unsigned long func_id)
423 {
424 	dev_err(dev, FW_BUG "tpm_crb: incorrect start method\n");
425 	return -EINVAL;
426 }
427 #endif
428 
crb_send(struct tpm_chip * chip,u8 * buf,size_t len)429 static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
430 {
431 	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
432 	int rc = 0;
433 
434 	/* Zero the cancel register so that the next command will not get
435 	 * canceled.
436 	 */
437 	iowrite32(0, &priv->regs_t->ctrl_cancel);
438 
439 	if (len > priv->cmd_size) {
440 		dev_err(&chip->dev, "invalid command count value %zd %d\n",
441 			len, priv->cmd_size);
442 		return -E2BIG;
443 	}
444 
445 	/* Seems to be necessary for every command */
446 	if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON)
447 		__crb_cmd_ready(&chip->dev, priv);
448 
449 	memcpy_toio(priv->cmd, buf, len);
450 
451 	/* Make sure that cmd is populated before issuing start. */
452 	wmb();
453 
454 	/* The reason for the extra quirk is that the PTT in 4th Gen Core CPUs
455 	 * report only ACPI start but in practice seems to require both
456 	 * CRB start, hence invoking CRB start method if hid == MSFT0101.
457 	 */
458 	if (priv->sm == ACPI_TPM2_COMMAND_BUFFER ||
459 	    priv->sm == ACPI_TPM2_MEMORY_MAPPED ||
460 	    !strcmp(priv->hid, "MSFT0101"))
461 		iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
462 
463 	if (priv->sm == ACPI_TPM2_START_METHOD ||
464 	    priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)
465 		rc = crb_do_acpi_start(chip);
466 
467 	if (priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) {
468 		iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
469 		rc = tpm_crb_smc_start(&chip->dev, priv->smc_func_id);
470 	}
471 
472 	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
473 		iowrite32(CRB_START_INVOKE, &priv->regs_t->ctrl_start);
474 		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND, chip->locality);
475 	}
476 
477 	if (rc)
478 		return rc;
479 
480 	return crb_try_pluton_doorbell(priv, false);
481 }
482 
crb_cancel(struct tpm_chip * chip)483 static void crb_cancel(struct tpm_chip *chip)
484 {
485 	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
486 	int rc;
487 
488 	iowrite32(CRB_CANCEL_INVOKE, &priv->regs_t->ctrl_cancel);
489 
490 	if ((priv->sm == ACPI_TPM2_START_METHOD ||
491 	     priv->sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD) &&
492 	     crb_do_acpi_start(chip))
493 		dev_err(&chip->dev, "ACPI Start failed\n");
494 
495 	if (priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
496 		rc = tpm_crb_ffa_start(CRB_FFA_START_TYPE_COMMAND, chip->locality);
497 		if (rc)
498 			dev_err(&chip->dev, "FF-A Start failed\n");
499 	}
500 }
501 
crb_req_canceled(struct tpm_chip * chip,u8 status)502 static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
503 {
504 	struct crb_priv *priv = dev_get_drvdata(&chip->dev);
505 	u32 cancel = ioread32(&priv->regs_t->ctrl_cancel);
506 
507 	return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE;
508 }
509 
510 static const struct tpm_class_ops tpm_crb = {
511 	.flags = TPM_OPS_AUTO_STARTUP,
512 	.status = crb_status,
513 	.recv = crb_recv,
514 	.send = crb_send,
515 	.cancel = crb_cancel,
516 	.req_canceled = crb_req_canceled,
517 	.go_idle  = crb_go_idle,
518 	.cmd_ready = crb_cmd_ready,
519 	.request_locality = crb_request_locality,
520 	.relinquish_locality = crb_relinquish_locality,
521 	.req_complete_mask = CRB_DRV_STS_COMPLETE,
522 	.req_complete_val = CRB_DRV_STS_COMPLETE,
523 };
524 
crb_check_resource(struct acpi_resource * ares,void * data)525 static int crb_check_resource(struct acpi_resource *ares, void *data)
526 {
527 	struct resource *iores_array = data;
528 	struct resource_win win;
529 	struct resource *res = &(win.res);
530 	int i;
531 
532 	if (acpi_dev_resource_memory(ares, res) ||
533 	    acpi_dev_resource_address_space(ares, &win)) {
534 		for (i = 0; i < TPM_CRB_MAX_RESOURCES + 1; ++i) {
535 			if (resource_type(iores_array + i) != IORESOURCE_MEM) {
536 				iores_array[i] = *res;
537 				iores_array[i].name = NULL;
538 				break;
539 			}
540 		}
541 	}
542 
543 	return 1;
544 }
545 
crb_map_res(struct device * dev,struct resource * iores,void __iomem ** iobase_ptr,u64 start,u32 size)546 static void __iomem *crb_map_res(struct device *dev, struct resource *iores,
547 				 void __iomem **iobase_ptr, u64 start, u32 size)
548 {
549 	struct resource new_res = {
550 		.start	= start,
551 		.end	= start + size - 1,
552 		.flags	= IORESOURCE_MEM,
553 	};
554 
555 	/* Detect a 64 bit address on a 32 bit system */
556 	if (start != new_res.start)
557 		return IOMEM_ERR_PTR(-EINVAL);
558 
559 	if (!iores)
560 		return devm_ioremap_resource(dev, &new_res);
561 
562 	if (!*iobase_ptr) {
563 		*iobase_ptr = devm_ioremap_resource(dev, iores);
564 		if (IS_ERR(*iobase_ptr))
565 			return *iobase_ptr;
566 	}
567 
568 	return *iobase_ptr + (new_res.start - iores->start);
569 }
570 
571 /*
572  * Work around broken BIOSs that return inconsistent values from the ACPI
573  * region vs the registers. Trust the ACPI region. Such broken systems
574  * probably cannot send large TPM commands since the buffer will be truncated.
575  */
crb_fixup_cmd_size(struct device * dev,struct resource * io_res,u64 start,u64 size)576 static u64 crb_fixup_cmd_size(struct device *dev, struct resource *io_res,
577 			      u64 start, u64 size)
578 {
579 	if (io_res->start > start || io_res->end < start)
580 		return size;
581 
582 	if (start + size - 1 <= io_res->end)
583 		return size;
584 
585 	dev_err(dev,
586 		FW_BUG "ACPI region does not cover the entire command/response buffer. %pr vs %llx %llx\n",
587 		io_res, start, size);
588 
589 	return io_res->end - start + 1;
590 }
591 
crb_map_io(struct acpi_device * device,struct crb_priv * priv,struct acpi_table_tpm2 * buf)592 static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
593 		      struct acpi_table_tpm2 *buf)
594 {
595 	struct list_head acpi_resource_list;
596 	struct resource iores_array[TPM_CRB_MAX_RESOURCES + 1] = { {0} };
597 	void __iomem *iobase_array[TPM_CRB_MAX_RESOURCES] = {NULL};
598 	struct device *dev = &device->dev;
599 	struct resource *iores;
600 	void __iomem **iobase_ptr;
601 	int i;
602 	u32 pa_high, pa_low;
603 	u64 cmd_pa;
604 	u32 cmd_size;
605 	__le64 __rsp_pa;
606 	u64 rsp_pa;
607 	u32 rsp_size;
608 	int ret;
609 
610 	/*
611 	 * Pluton sometimes does not define ACPI memory regions.
612 	 * Mapping is then done in crb_map_pluton
613 	 */
614 	if (priv->sm != ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) {
615 		INIT_LIST_HEAD(&acpi_resource_list);
616 		ret = acpi_dev_get_resources(device, &acpi_resource_list,
617 					     crb_check_resource, iores_array);
618 		if (ret < 0)
619 			return ret;
620 		acpi_dev_free_resource_list(&acpi_resource_list);
621 
622 		if (resource_type(iores_array) != IORESOURCE_MEM) {
623 			dev_err(dev, FW_BUG "TPM2 ACPI table does not define a memory resource\n");
624 			return -EINVAL;
625 		} else if (resource_type(iores_array + TPM_CRB_MAX_RESOURCES) ==
626 			   IORESOURCE_MEM) {
627 			dev_warn(dev, "TPM2 ACPI table defines too many memory resources\n");
628 			memset(iores_array + TPM_CRB_MAX_RESOURCES,
629 			       0, sizeof(*iores_array));
630 			iores_array[TPM_CRB_MAX_RESOURCES].flags = 0;
631 		}
632 	}
633 
634 	iores = NULL;
635 	iobase_ptr = NULL;
636 	for (i = 0; resource_type(iores_array + i) == IORESOURCE_MEM; ++i) {
637 		if (buf->control_address >= iores_array[i].start &&
638 		    buf->control_address + sizeof(struct crb_regs_tail) - 1 <=
639 		    iores_array[i].end) {
640 			iores = iores_array + i;
641 			iobase_ptr = iobase_array + i;
642 			break;
643 		}
644 	}
645 
646 	priv->regs_t = crb_map_res(dev, iores, iobase_ptr, buf->control_address,
647 				   sizeof(struct crb_regs_tail));
648 
649 	if (IS_ERR(priv->regs_t))
650 		return PTR_ERR(priv->regs_t);
651 
652 	/* The ACPI IO region starts at the head area and continues to include
653 	 * the control area, as one nice sane region except for some older
654 	 * stuff that puts the control area outside the ACPI IO region.
655 	 */
656 	if (priv->sm == ACPI_TPM2_COMMAND_BUFFER ||
657 	    priv->sm == ACPI_TPM2_CRB_WITH_ARM_FFA ||
658 	    priv->sm == ACPI_TPM2_MEMORY_MAPPED) {
659 		if (iores &&
660 		    buf->control_address == iores->start +
661 		    sizeof(*priv->regs_h))
662 			priv->regs_h = *iobase_ptr;
663 		else
664 			dev_warn(dev, FW_BUG "Bad ACPI memory layout");
665 	}
666 
667 	ret = __crb_request_locality(dev, priv, 0);
668 	if (ret)
669 		return ret;
670 
671 	/*
672 	 * PTT HW bug w/a: wake up the device to access
673 	 * possibly not retained registers.
674 	 */
675 	ret = __crb_cmd_ready(dev, priv);
676 	if (ret)
677 		goto out_relinquish_locality;
678 
679 	pa_high = ioread32(&priv->regs_t->ctrl_cmd_pa_high);
680 	pa_low  = ioread32(&priv->regs_t->ctrl_cmd_pa_low);
681 	cmd_pa = ((u64)pa_high << 32) | pa_low;
682 	cmd_size = ioread32(&priv->regs_t->ctrl_cmd_size);
683 
684 	iores = NULL;
685 	iobase_ptr = NULL;
686 	for (i = 0; iores_array[i].end; ++i) {
687 		if (cmd_pa >= iores_array[i].start &&
688 		    cmd_pa <= iores_array[i].end) {
689 			iores = iores_array + i;
690 			iobase_ptr = iobase_array + i;
691 			break;
692 		}
693 	}
694 
695 	if (iores)
696 		cmd_size = crb_fixup_cmd_size(dev, iores, cmd_pa, cmd_size);
697 
698 	dev_dbg(dev, "cmd_hi = %X cmd_low = %X cmd_size %X\n",
699 		pa_high, pa_low, cmd_size);
700 
701 	priv->cmd = crb_map_res(dev, iores, iobase_ptr,	cmd_pa, cmd_size);
702 	if (IS_ERR(priv->cmd)) {
703 		ret = PTR_ERR(priv->cmd);
704 		goto out;
705 	}
706 
707 	memcpy_fromio(&__rsp_pa, &priv->regs_t->ctrl_rsp_pa, 8);
708 	rsp_pa = le64_to_cpu(__rsp_pa);
709 	rsp_size = ioread32(&priv->regs_t->ctrl_rsp_size);
710 
711 	iores = NULL;
712 	iobase_ptr = NULL;
713 	for (i = 0; resource_type(iores_array + i) == IORESOURCE_MEM; ++i) {
714 		if (rsp_pa >= iores_array[i].start &&
715 		    rsp_pa <= iores_array[i].end) {
716 			iores = iores_array + i;
717 			iobase_ptr = iobase_array + i;
718 			break;
719 		}
720 	}
721 
722 	if (iores)
723 		rsp_size = crb_fixup_cmd_size(dev, iores, rsp_pa, rsp_size);
724 
725 	if (cmd_pa != rsp_pa) {
726 		priv->rsp = crb_map_res(dev, iores, iobase_ptr,
727 					rsp_pa, rsp_size);
728 		ret = PTR_ERR_OR_ZERO(priv->rsp);
729 		goto out;
730 	}
731 
732 	/* According to the PTP specification, overlapping command and response
733 	 * buffer sizes must be identical.
734 	 */
735 	if (cmd_size != rsp_size) {
736 		dev_err(dev, FW_BUG "overlapping command and response buffer sizes are not identical");
737 		ret = -EINVAL;
738 		goto out;
739 	}
740 
741 	priv->rsp = priv->cmd;
742 
743 out:
744 	if (!ret)
745 		priv->cmd_size = cmd_size;
746 
747 	__crb_go_idle(dev, priv);
748 
749 out_relinquish_locality:
750 
751 	__crb_relinquish_locality(dev, priv, 0);
752 
753 	return ret;
754 }
755 
crb_map_pluton(struct device * dev,struct crb_priv * priv,struct acpi_table_tpm2 * buf,struct tpm2_crb_pluton * crb_pluton)756 static int crb_map_pluton(struct device *dev, struct crb_priv *priv,
757 	       struct acpi_table_tpm2 *buf, struct tpm2_crb_pluton *crb_pluton)
758 {
759 	priv->pluton_start_addr = crb_map_res(dev, NULL, NULL,
760 					      crb_pluton->start_addr, 4);
761 	if (IS_ERR(priv->pluton_start_addr))
762 		return PTR_ERR(priv->pluton_start_addr);
763 
764 	priv->pluton_reply_addr = crb_map_res(dev, NULL, NULL,
765 					      crb_pluton->reply_addr, 4);
766 	if (IS_ERR(priv->pluton_reply_addr))
767 		return PTR_ERR(priv->pluton_reply_addr);
768 
769 	return 0;
770 }
771 
crb_acpi_add(struct acpi_device * device)772 static int crb_acpi_add(struct acpi_device *device)
773 {
774 	struct acpi_table_tpm2 *buf;
775 	struct crb_priv *priv;
776 	struct tpm_chip *chip;
777 	struct device *dev = &device->dev;
778 	struct tpm2_crb_smc *crb_smc;
779 	struct tpm2_crb_ffa *crb_ffa;
780 	struct tpm2_crb_pluton *crb_pluton;
781 	acpi_status status;
782 	u32 sm;
783 	int rc;
784 
785 	status = acpi_get_table(ACPI_SIG_TPM2, 1,
786 				(struct acpi_table_header **) &buf);
787 	if (ACPI_FAILURE(status) || buf->header.length < sizeof(*buf)) {
788 		dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n");
789 		return -EINVAL;
790 	}
791 
792 	/* Should the FIFO driver handle this? */
793 	sm = buf->start_method;
794 	if (sm == ACPI_TPM2_MEMORY_MAPPED) {
795 		rc = -ENODEV;
796 		goto out;
797 	}
798 
799 	priv = devm_kzalloc(dev, sizeof(struct crb_priv), GFP_KERNEL);
800 	if (!priv) {
801 		rc = -ENOMEM;
802 		goto out;
803 	}
804 
805 	if (sm == ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC) {
806 		if (buf->header.length < (sizeof(*buf) + sizeof(*crb_smc))) {
807 			dev_err(dev,
808 				FW_BUG "TPM2 ACPI table has wrong size %u for start method type %d\n",
809 				buf->header.length,
810 				ACPI_TPM2_COMMAND_BUFFER_WITH_ARM_SMC);
811 			rc = -EINVAL;
812 			goto out;
813 		}
814 		crb_smc = ACPI_ADD_PTR(struct tpm2_crb_smc, buf, sizeof(*buf));
815 		priv->smc_func_id = crb_smc->smc_func_id;
816 	}
817 
818 	if (sm == ACPI_TPM2_CRB_WITH_ARM_FFA) {
819 		if (buf->header.length < (sizeof(*buf) + sizeof(*crb_ffa))) {
820 			dev_err(dev,
821 				FW_BUG "TPM2 ACPI table has wrong size %u for start method type %d\n",
822 				buf->header.length,
823 				ACPI_TPM2_CRB_WITH_ARM_FFA);
824 			rc = -EINVAL;
825 			goto out;
826 		}
827 		crb_ffa = ACPI_ADD_PTR(struct tpm2_crb_ffa, buf, sizeof(*buf));
828 		priv->ffa_flags = crb_ffa->flags;
829 		priv->ffa_attributes = crb_ffa->attributes;
830 		rc = tpm_crb_ffa_init();
831 		if (rc) {
832 			/* If FF-A driver is not available yet, request probe retry */
833 			if (rc == -ENOENT)
834 				rc = -EPROBE_DEFER;
835 			goto out;
836 		}
837 	}
838 
839 	if (sm == ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) {
840 		if (buf->header.length < (sizeof(*buf) + sizeof(*crb_pluton))) {
841 			dev_err(dev,
842 				FW_BUG "TPM2 ACPI table has wrong size %u for start method type %d\n",
843 				buf->header.length,
844 				ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON);
845 			rc = -EINVAL;
846 			goto out;
847 		}
848 		crb_pluton = ACPI_ADD_PTR(struct tpm2_crb_pluton, buf, sizeof(*buf));
849 		rc = crb_map_pluton(dev, priv, buf, crb_pluton);
850 		if (rc)
851 			goto out;
852 	}
853 
854 	priv->sm = sm;
855 	priv->hid = acpi_device_hid(device);
856 
857 	rc = crb_map_io(device, priv, buf);
858 	if (rc)
859 		goto out;
860 
861 	chip = tpmm_chip_alloc(dev, &tpm_crb);
862 	if (IS_ERR(chip)) {
863 		rc = PTR_ERR(chip);
864 		goto out;
865 	}
866 
867 	dev_set_drvdata(&chip->dev, priv);
868 	chip->acpi_dev_handle = device->handle;
869 	chip->flags = TPM_CHIP_FLAG_TPM2;
870 
871 	rc = tpm_chip_bootstrap(chip);
872 	if (rc)
873 		goto out;
874 
875 #ifdef CONFIG_X86
876 	/* A quirk for https://www.amd.com/en/support/kb/faq/pa-410 */
877 	if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
878 	    priv->sm != ACPI_TPM2_COMMAND_BUFFER_WITH_PLUTON) {
879 		dev_info(dev, "Disabling hwrng\n");
880 		chip->flags |= TPM_CHIP_FLAG_HWRNG_DISABLED;
881 	}
882 #endif /* CONFIG_X86 */
883 
884 	rc = tpm_chip_register(chip);
885 
886 out:
887 	acpi_put_table((struct acpi_table_header *)buf);
888 	return rc;
889 }
890 
crb_acpi_remove(struct acpi_device * device)891 static void crb_acpi_remove(struct acpi_device *device)
892 {
893 	struct device *dev = &device->dev;
894 	struct tpm_chip *chip = dev_get_drvdata(dev);
895 
896 	tpm_chip_unregister(chip);
897 }
898 
899 static const struct dev_pm_ops crb_pm = {
900 	SET_SYSTEM_SLEEP_PM_OPS(tpm_pm_suspend, tpm_pm_resume)
901 };
902 
903 static const struct acpi_device_id crb_device_ids[] = {
904 	{"MSFT0101", 0},
905 	{"", 0},
906 };
907 MODULE_DEVICE_TABLE(acpi, crb_device_ids);
908 
909 static struct acpi_driver crb_acpi_driver = {
910 	.name = "tpm_crb",
911 	.ids = crb_device_ids,
912 	.ops = {
913 		.add = crb_acpi_add,
914 		.remove = crb_acpi_remove,
915 	},
916 	.drv = {
917 		.pm = &crb_pm,
918 	},
919 };
920 
921 module_acpi_driver(crb_acpi_driver);
922 MODULE_AUTHOR("Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>");
923 MODULE_DESCRIPTION("TPM2 Driver");
924 MODULE_VERSION("0.1");
925 MODULE_LICENSE("GPL");
926