xref: /optee_os/core/drivers/stm32_bsec.c (revision ef9888dc73edbd3a3935e432320f5e6644e5cd2a)
1 // SPDX-License-Identifier: BSD-3-Clause
2 /*
3  * Copyright (c) 2017-2020, STMicroelectronics
4  */
5 
6 #include <assert.h>
7 #include <drivers/stm32_bsec.h>
8 #include <io.h>
9 #include <kernel/delay.h>
10 #include <kernel/generic_boot.h>
11 #include <kernel/spinlock.h>
12 #include <limits.h>
13 #include <mm/core_memprot.h>
14 #include <platform_config.h>
15 #include <stm32_util.h>
16 #include <string.h>
17 #include <tee_api_defines.h>
18 #include <types_ext.h>
19 #include <util.h>
20 
21 #define BSEC_OTP_MASK			GENMASK_32(4, 0)
22 #define BSEC_OTP_BANK_SHIFT		5
23 
24 /* Permanent lock bitmasks */
25 #define ADDR_LOWER_OTP_PERLOCK_SHIFT	3
26 #define DATA_LOWER_OTP_PERLOCK_BIT	3
27 #define DATA_LOWER_OTP_PERLOCK_MASK	GENMASK_32(2, 0)
28 #define ADDR_UPPER_OTP_PERLOCK_SHIFT	4
29 #define DATA_UPPER_OTP_PERLOCK_BIT	1
30 #define DATA_UPPER_OTP_PERLOCK_MASK	GENMASK_32(3, 0)
31 
32 /* BSEC register offset */
33 #define BSEC_OTP_CONF_OFF		0x000U
34 #define BSEC_OTP_CTRL_OFF		0x004U
35 #define BSEC_OTP_WRDATA_OFF		0x008U
36 #define BSEC_OTP_STATUS_OFF		0x00CU
37 #define BSEC_OTP_LOCK_OFF		0x010U
38 #define BSEC_DEN_OFF			0x014U
39 #define BSEC_FEN_OFF			0x018U
40 #define BSEC_DISTURBED_OFF		0x01CU
41 #define BSEC_DISTURBED1_OFF		0x020U
42 #define BSEC_DISTURBED2_OFF		0x024U
43 #define BSEC_ERROR_OFF			0x034U
44 #define BSEC_ERROR1_OFF			0x038U
45 #define BSEC_ERROR2_OFF			0x03CU
46 #define BSEC_WRLOCK_OFF			0x04CU
47 #define BSEC_WRLOCK1_OFF		0x050U
48 #define BSEC_WRLOCK2_OFF		0x054U
49 #define BSEC_SPLOCK_OFF			0x064U
50 #define BSEC_SPLOCK1_OFF		0x068U
51 #define BSEC_SPLOCK2_OFF		0x06CU
52 #define BSEC_SWLOCK_OFF			0x07CU
53 #define BSEC_SWLOCK1_OFF		0x080U
54 #define BSEC_SWLOCK2_OFF		0x084U
55 #define BSEC_SRLOCK_OFF			0x094U
56 #define BSEC_SRLOCK1_OFF		0x098U
57 #define BSEC_SRLOCK2_OFF		0x09CU
58 #define BSEC_JTAG_IN_OFF		0x0ACU
59 #define BSEC_JTAG_OUT_OFF		0x0B0U
60 #define BSEC_SCRATCH_OFF		0x0B4U
61 #define BSEC_OTP_DATA_OFF		0x200U
62 #define BSEC_IPHW_CFG_OFF		0xFF0U
63 #define BSEC_IPVR_OFF			0xFF4U
64 #define BSEC_IP_ID_OFF			0xFF8U
65 #define BSEC_IP_MAGIC_ID_OFF		0xFFCU
66 
67 /* BSEC_CONFIGURATION Register */
68 #define BSEC_CONF_POWER_UP_MASK		BIT(0)
69 #define BSEC_CONF_POWER_UP_SHIFT	0
70 #define BSEC_CONF_FRQ_MASK		GENMASK_32(2, 1)
71 #define BSEC_CONF_FRQ_SHIFT		1
72 #define BSEC_CONF_PRG_WIDTH_MASK	GENMASK_32(6, 3)
73 #define BSEC_CONF_PRG_WIDTH_SHIFT	3
74 #define BSEC_CONF_TREAD_MASK		GENMASK_32(8, 7)
75 #define BSEC_CONF_TREAD_SHIFT		7
76 
77 /* BSEC_CONTROL Register */
78 #define BSEC_READ			0x000U
79 #define BSEC_WRITE			0x100U
80 #define BSEC_LOCK			0x200U
81 
82 /* BSEC_STATUS Register */
83 #define BSEC_MODE_STATUS_MASK		GENMASK_32(2, 0)
84 #define BSEC_MODE_BUSY_MASK		BIT(3)
85 #define BSEC_MODE_PROGFAIL_MASK		BIT(4)
86 #define BSEC_MODE_PWR_MASK		BIT(5)
87 #define BSEC_MODE_BIST1_LOCK_MASK	BIT(6)
88 #define BSEC_MODE_BIST2_LOCK_MASK	BIT(7)
89 
90 /* BSEC_DEBUG */
91 #define BSEC_HDPEN			BIT(4)
92 #define BSEC_SPIDEN			BIT(5)
93 #define BSEC_SPINDEN			BIT(6)
94 #define BSEC_DBGSWGEN			BIT(10)
95 #define BSEC_DEN_ALL_MSK		GENMASK_32(10, 0)
96 
97 /*
98  * OTP Lock services definition
99  * Value must corresponding to the bit position in the register
100  */
101 #define BSEC_LOCK_UPPER_OTP		0x00
102 #define BSEC_LOCK_DEBUG			0x02
103 #define BSEC_LOCK_PROGRAM		0x04
104 
105 /* Timeout when polling on status */
106 #define BSEC_TIMEOUT_US			1000
107 
108 struct bsec_dev {
109 	struct io_pa_va base;
110 	unsigned int upper_base;
111 	unsigned int max_id;
112 	bool closed_device;
113 };
114 
115 /* Only 1 instance of BSEC is expected per platform */
116 static struct bsec_dev bsec_dev;
117 
118 /* BSEC access protection */
119 static unsigned int lock = SPINLOCK_UNLOCK;
120 
121 static uint32_t bsec_lock(void)
122 {
123 	return may_spin_lock(&lock);
124 }
125 
126 static void bsec_unlock(uint32_t exceptions)
127 {
128 	may_spin_unlock(&lock, exceptions);
129 }
130 
131 static uint32_t otp_max_id(void)
132 {
133 	return bsec_dev.max_id;
134 }
135 
136 static uint32_t otp_bank_offset(uint32_t otp_id)
137 {
138 	assert(otp_id <= otp_max_id());
139 
140 	return ((otp_id & ~BSEC_OTP_MASK) >> BSEC_OTP_BANK_SHIFT) *
141 		sizeof(uint32_t);
142 }
143 
144 static vaddr_t bsec_base(void)
145 {
146 	return io_pa_or_va_secure(&bsec_dev.base);
147 }
148 
149 static uint32_t bsec_status(void)
150 {
151 	return io_read32(bsec_base() + BSEC_OTP_STATUS_OFF);
152 }
153 
154 static TEE_Result check_no_error(uint32_t otp_id)
155 {
156 	uint32_t bit = BIT(otp_id & BSEC_OTP_MASK);
157 	uint32_t bank = otp_bank_offset(otp_id);
158 
159 	if (io_read32(bsec_base() + BSEC_DISTURBED_OFF + bank) & bit)
160 		return TEE_ERROR_GENERIC;
161 
162 	if (io_read32(bsec_base() + BSEC_ERROR_OFF + bank) & bit)
163 		return TEE_ERROR_GENERIC;
164 
165 	return TEE_SUCCESS;
166 }
167 
168 static TEE_Result power_up_safmem(void)
169 {
170 	uint64_t timeout_ref = timeout_init_us(BSEC_TIMEOUT_US);
171 
172 	io_mask32(bsec_base() + BSEC_OTP_CONF_OFF, BSEC_CONF_POWER_UP_MASK,
173 		  BSEC_CONF_POWER_UP_MASK);
174 
175 	/*
176 	 * If a timeout is detected, test the condition again to consider
177 	 * cases where timeout is due to the executing TEE thread rescheduling.
178 	 */
179 	while (!timeout_elapsed(timeout_ref))
180 		if (bsec_status() & BSEC_MODE_PWR_MASK)
181 			break;
182 
183 	if (bsec_status() & BSEC_MODE_PWR_MASK)
184 		return TEE_SUCCESS;
185 
186 	return TEE_ERROR_GENERIC;
187 }
188 
189 static TEE_Result power_down_safmem(void)
190 {
191 	uint64_t timeout_ref = timeout_init_us(BSEC_TIMEOUT_US);
192 
193 	io_mask32(bsec_base() + BSEC_OTP_CONF_OFF, 0, BSEC_CONF_POWER_UP_MASK);
194 
195 	/*
196 	 * If a timeout is detected, test the condition again to consider
197 	 * cases where timeout is due to the executing TEE thread rescheduling.
198 	 */
199 	while (!timeout_elapsed(timeout_ref))
200 		if (!(bsec_status() & BSEC_MODE_PWR_MASK))
201 			break;
202 
203 	if (!(bsec_status() & BSEC_MODE_PWR_MASK))
204 		return TEE_SUCCESS;
205 
206 	return TEE_ERROR_GENERIC;
207 }
208 
209 TEE_Result stm32_bsec_shadow_register(uint32_t otp_id)
210 {
211 	TEE_Result result = 0;
212 	uint32_t exceptions = 0;
213 	uint64_t timeout_ref = 0;
214 	bool locked = false;
215 
216 	/* Check if shadowing of OTP is locked, informative only */
217 	result = stm32_bsec_read_sr_lock(otp_id, &locked);
218 	if (result)
219 		return result;
220 
221 	if (locked)
222 		DMSG("BSEC shadow warning: OTP locked");
223 
224 	exceptions = bsec_lock();
225 
226 	result = power_up_safmem();
227 	if (result)
228 		return result;
229 
230 	io_write32(bsec_base() + BSEC_OTP_CTRL_OFF, otp_id | BSEC_READ);
231 
232 	timeout_ref = timeout_init_us(BSEC_TIMEOUT_US);
233 	while (!timeout_elapsed(timeout_ref))
234 		if (!(bsec_status() & BSEC_MODE_BUSY_MASK))
235 			break;
236 
237 	if (bsec_status() & BSEC_MODE_BUSY_MASK)
238 		result = TEE_ERROR_GENERIC;
239 	else
240 		result = check_no_error(otp_id);
241 
242 	power_down_safmem();
243 
244 	bsec_unlock(exceptions);
245 
246 	return result;
247 }
248 
249 TEE_Result stm32_bsec_read_otp(uint32_t *value, uint32_t otp_id)
250 {
251 	TEE_Result result = 0;
252 	uint32_t exceptions = 0;
253 
254 	if (otp_id > otp_max_id())
255 		return TEE_ERROR_BAD_PARAMETERS;
256 
257 	exceptions = bsec_lock();
258 
259 	*value = io_read32(bsec_base() + BSEC_OTP_DATA_OFF +
260 			   (otp_id * sizeof(uint32_t)));
261 
262 	result = check_no_error(otp_id);
263 
264 	bsec_unlock(exceptions);
265 
266 	return result;
267 }
268 
269 TEE_Result stm32_bsec_shadow_read_otp(uint32_t *otp_value, uint32_t otp_id)
270 {
271 	TEE_Result result = 0;
272 
273 	result = stm32_bsec_shadow_register(otp_id);
274 	if (result) {
275 		EMSG("BSEC %"PRIu32" Shadowing Error %#"PRIx32, otp_id, result);
276 		return result;
277 	}
278 
279 	result = stm32_bsec_read_otp(otp_value, otp_id);
280 	if (result)
281 		EMSG("BSEC %"PRIu32" Read Error %#"PRIx32, otp_id, result);
282 
283 	return result;
284 }
285 
286 TEE_Result stm32_bsec_write_otp(uint32_t value, uint32_t otp_id)
287 {
288 	TEE_Result result = 0;
289 	uint32_t exceptions = 0;
290 	vaddr_t otp_data_base = bsec_base() + BSEC_OTP_DATA_OFF;
291 	bool locked = false;
292 
293 	/* Check if write of OTP is locked, informative only */
294 	result = stm32_bsec_read_sw_lock(otp_id, &locked);
295 	if (result)
296 		return result;
297 
298 	if (locked)
299 		DMSG("BSEC write warning: OTP locked");
300 
301 	exceptions = bsec_lock();
302 
303 	io_write32(otp_data_base + (otp_id * sizeof(uint32_t)), value);
304 
305 	result = check_no_error(otp_id);
306 
307 	bsec_unlock(exceptions);
308 
309 	return result;
310 }
311 
312 TEE_Result stm32_bsec_program_otp(uint32_t value, uint32_t otp_id)
313 {
314 	TEE_Result result = 0;
315 	uint32_t exceptions = 0;
316 	uint64_t timeout_ref = 0;
317 	bool locked = false;
318 
319 	/* Check if shadowing of OTP is locked, informative only */
320 	result = stm32_bsec_read_sp_lock(otp_id, &locked);
321 	if (result)
322 		return result;
323 
324 	if (locked)
325 		DMSG("BSEC program warning: OTP locked");
326 
327 	if (io_read32(bsec_base() + BSEC_OTP_LOCK_OFF) & BIT(BSEC_LOCK_PROGRAM))
328 		DMSG("BSEC program warning: GPLOCK activated");
329 
330 	exceptions = bsec_lock();
331 
332 	result = power_up_safmem();
333 	if (result)
334 		return result;
335 
336 	io_write32(bsec_base() + BSEC_OTP_WRDATA_OFF, value);
337 	io_write32(bsec_base() + BSEC_OTP_CTRL_OFF, otp_id | BSEC_WRITE);
338 
339 	timeout_ref = timeout_init_us(BSEC_TIMEOUT_US);
340 	while (!timeout_elapsed(timeout_ref))
341 		if (!(bsec_status() & BSEC_MODE_BUSY_MASK))
342 			break;
343 
344 	if (bsec_status() & (BSEC_MODE_BUSY_MASK | BSEC_MODE_PROGFAIL_MASK))
345 		result = TEE_ERROR_GENERIC;
346 	else
347 		result = check_no_error(otp_id);
348 
349 	power_down_safmem();
350 
351 	bsec_unlock(exceptions);
352 
353 	return result;
354 }
355 
356 TEE_Result stm32_bsec_permanent_lock_otp(uint32_t otp_id)
357 {
358 	TEE_Result result = 0;
359 	uint32_t data = 0;
360 	uint32_t addr = 0;
361 	uint32_t exceptions = 0;
362 	vaddr_t base = bsec_base();
363 	uint64_t timeout_ref;
364 
365 	if (otp_id > otp_max_id())
366 		return TEE_ERROR_BAD_PARAMETERS;
367 
368 	if (otp_id < bsec_dev.upper_base) {
369 		addr = otp_id >> ADDR_LOWER_OTP_PERLOCK_SHIFT;
370 		data = DATA_LOWER_OTP_PERLOCK_BIT <<
371 		       ((otp_id & DATA_LOWER_OTP_PERLOCK_MASK) << 1U);
372 	} else {
373 		addr = (otp_id >> ADDR_UPPER_OTP_PERLOCK_SHIFT) + 2U;
374 		data = DATA_UPPER_OTP_PERLOCK_BIT <<
375 		       (otp_id & DATA_UPPER_OTP_PERLOCK_MASK);
376 	}
377 
378 	exceptions = bsec_lock();
379 
380 	result = power_up_safmem();
381 	if (result)
382 		return result;
383 
384 	io_write32(base + BSEC_OTP_WRDATA_OFF, data);
385 	io_write32(base + BSEC_OTP_CTRL_OFF, addr | BSEC_WRITE | BSEC_LOCK);
386 
387 	timeout_ref = timeout_init_us(BSEC_TIMEOUT_US);
388 	while (!timeout_elapsed(timeout_ref))
389 		if (!(bsec_status() & BSEC_MODE_BUSY_MASK))
390 			break;
391 
392 	if (bsec_status() & (BSEC_MODE_BUSY_MASK | BSEC_MODE_PROGFAIL_MASK))
393 		result = TEE_ERROR_BAD_PARAMETERS;
394 	else
395 		result = check_no_error(otp_id);
396 
397 	power_down_safmem();
398 
399 	bsec_unlock(exceptions);
400 
401 	return result;
402 }
403 
404 TEE_Result stm32_bsec_write_debug_conf(uint32_t value)
405 {
406 	TEE_Result result = TEE_ERROR_GENERIC;
407 	uint32_t masked_val = value & BSEC_DEN_ALL_MSK;
408 	uint32_t exceptions = 0;
409 
410 	exceptions = bsec_lock();
411 
412 	io_write32(bsec_base() + BSEC_DEN_OFF, value);
413 
414 	if ((io_read32(bsec_base() + BSEC_DEN_OFF) ^ masked_val) == 0U)
415 		result = TEE_SUCCESS;
416 
417 	bsec_unlock(exceptions);
418 
419 	return result;
420 }
421 
422 uint32_t stm32_bsec_read_debug_conf(void)
423 {
424 	return io_read32(bsec_base() + BSEC_DEN_OFF);
425 }
426 
427 static TEE_Result set_bsec_lock(uint32_t otp_id, size_t lock_offset)
428 {
429 	uint32_t bank = otp_bank_offset(otp_id);
430 	uint32_t otp_mask = BIT(otp_id & BSEC_OTP_MASK);
431 	vaddr_t lock_addr = bsec_base() + bank + lock_offset;
432 	uint32_t exceptions = 0;
433 
434 	if (otp_id > STM32MP1_OTP_MAX_ID)
435 		return TEE_ERROR_BAD_PARAMETERS;
436 
437 	exceptions = bsec_lock();
438 
439 	io_write32(lock_addr, otp_mask);
440 
441 	bsec_unlock(exceptions);
442 
443 	return TEE_SUCCESS;
444 }
445 
446 TEE_Result stm32_bsec_set_sr_lock(uint32_t otp_id)
447 {
448 	return set_bsec_lock(otp_id, BSEC_SRLOCK_OFF);
449 }
450 
451 TEE_Result stm32_bsec_set_sw_lock(uint32_t otp_id)
452 {
453 	return set_bsec_lock(otp_id, BSEC_SWLOCK_OFF);
454 }
455 
456 TEE_Result stm32_bsec_set_sp_lock(uint32_t otp_id)
457 {
458 	return set_bsec_lock(otp_id, BSEC_SPLOCK_OFF);
459 }
460 
461 static TEE_Result read_bsec_lock(uint32_t otp_id, bool *locked,
462 				 size_t lock_offset)
463 {
464 	uint32_t bank = otp_bank_offset(otp_id);
465 	uint32_t otp_mask = BIT(otp_id & BSEC_OTP_MASK);
466 	vaddr_t lock_addr = bsec_base() + bank + lock_offset;
467 
468 	if (otp_id > STM32MP1_OTP_MAX_ID)
469 		return TEE_ERROR_BAD_PARAMETERS;
470 
471 	*locked = (io_read32(lock_addr) & otp_mask) != 0;
472 
473 	return TEE_SUCCESS;
474 }
475 
476 TEE_Result stm32_bsec_read_sr_lock(uint32_t otp_id, bool *locked)
477 {
478 	return read_bsec_lock(otp_id, locked, BSEC_SRLOCK_OFF);
479 }
480 
481 TEE_Result stm32_bsec_read_sw_lock(uint32_t otp_id, bool *locked)
482 {
483 	return read_bsec_lock(otp_id, locked, BSEC_SWLOCK_OFF);
484 }
485 
486 TEE_Result stm32_bsec_read_sp_lock(uint32_t otp_id, bool *locked)
487 {
488 	return read_bsec_lock(otp_id, locked, BSEC_SPLOCK_OFF);
489 }
490 
491 TEE_Result stm32_bsec_read_permanent_lock(uint32_t otp_id, bool *locked)
492 {
493 	return read_bsec_lock(otp_id, locked, BSEC_WRLOCK_OFF);
494 }
495 
496 TEE_Result stm32_bsec_otp_lock(uint32_t service)
497 {
498 	vaddr_t addr = bsec_base() + BSEC_OTP_LOCK_OFF;
499 
500 	switch (service) {
501 	case BSEC_LOCK_UPPER_OTP:
502 		io_write32(addr, BIT(BSEC_LOCK_UPPER_OTP));
503 		break;
504 	case BSEC_LOCK_DEBUG:
505 		io_write32(addr, BIT(BSEC_LOCK_DEBUG));
506 		break;
507 	case BSEC_LOCK_PROGRAM:
508 		io_write32(addr, BIT(BSEC_LOCK_PROGRAM));
509 		break;
510 	default:
511 		return TEE_ERROR_BAD_PARAMETERS;
512 	}
513 
514 	return TEE_SUCCESS;
515 }
516 
517 bool stm32_bsec_nsec_can_access_otp(uint32_t otp_id)
518 {
519 	if (otp_id > otp_max_id())
520 		return false;
521 
522 	return otp_id < bsec_dev.upper_base || !bsec_dev.closed_device;
523 }
524 
525 static TEE_Result initialize_bsec(void)
526 {
527 	struct stm32_bsec_static_cfg cfg = { 0 };
528 	uint32_t otp = 0;
529 	TEE_Result result = 0;
530 
531 	stm32mp_get_bsec_static_cfg(&cfg);
532 
533 	bsec_dev.base.pa = cfg.base;
534 	bsec_dev.upper_base = cfg.upper_start;
535 	bsec_dev.max_id = cfg.max_id;
536 	bsec_dev.closed_device = true;
537 
538 	/* Disable closed device mode upon platform closed device OTP value */
539 	result = stm32_bsec_shadow_read_otp(&otp, cfg.closed_device_id);
540 	if (!result && !(otp & BIT(cfg.closed_device_position)))
541 		bsec_dev.closed_device = false;
542 
543 	return TEE_SUCCESS;
544 }
545 
546 driver_init(initialize_bsec);
547