1 /*
2  * Copyright (c) 2017-2022, STMicroelectronics - All Rights Reserved
3  *
4  * SPDX-License-Identifier: BSD-3-Clause
5  */
6 
7 #include <assert.h>
8 #include <stdint.h>
9 
10 #include <common/debug.h>
11 #include <drivers/st/etzpc.h>
12 #include <drivers/st/stm32_gpio.h>
13 
14 #include <platform_def.h>
15 #include <stm32mp_shared_resources.h>
16 
17 /*
18  * Once one starts to get the resource registering state, one cannot register
19  * new resources. This ensures resource state cannot change.
20  */
21 static bool registering_locked;
22 
23 /*
24  * Shared peripherals and resources registration
25  *
26  * Each resource assignation is stored in a table. The state defaults
27  * to PERIPH_UNREGISTERED if the resource is not explicitly assigned.
28  *
29  * Resource driver that as not embedded (a.k.a their related CFG_xxx build
30  * directive is disabled) are assigned to the non-secure world.
31  *
32  * Each pin of the GPIOZ bank can be secure or non-secure.
33  *
34  * It is the platform responsibility the ensure resource assignation
35  * matches the access permission firewalls configuration.
36  */
37 enum shres_state {
38 	SHRES_UNREGISTERED = 0,
39 	SHRES_SECURE,
40 	SHRES_NON_SECURE,
41 };
42 
43 /* Force uint8_t array for array of enum shres_state for size considerations */
44 static uint8_t shres_state[STM32MP1_SHRES_COUNT];
45 
46 static const char *shres2str_id_tbl[STM32MP1_SHRES_COUNT] __unused = {
47 	[STM32MP1_SHRES_GPIOZ(0)] = "GPIOZ0",
48 	[STM32MP1_SHRES_GPIOZ(1)] = "GPIOZ1",
49 	[STM32MP1_SHRES_GPIOZ(2)] = "GPIOZ2",
50 	[STM32MP1_SHRES_GPIOZ(3)] = "GPIOZ3",
51 	[STM32MP1_SHRES_GPIOZ(4)] = "GPIOZ4",
52 	[STM32MP1_SHRES_GPIOZ(5)] = "GPIOZ5",
53 	[STM32MP1_SHRES_GPIOZ(6)] = "GPIOZ6",
54 	[STM32MP1_SHRES_GPIOZ(7)] = "GPIOZ7",
55 	[STM32MP1_SHRES_IWDG1] = "IWDG1",
56 	[STM32MP1_SHRES_USART1] = "USART1",
57 	[STM32MP1_SHRES_SPI6] = "SPI6",
58 	[STM32MP1_SHRES_I2C4] = "I2C4",
59 	[STM32MP1_SHRES_RNG1] = "RNG1",
60 	[STM32MP1_SHRES_HASH1] = "HASH1",
61 	[STM32MP1_SHRES_CRYP1] = "CRYP1",
62 	[STM32MP1_SHRES_I2C6] = "I2C6",
63 	[STM32MP1_SHRES_RTC] = "RTC",
64 	[STM32MP1_SHRES_MCU] = "MCU",
65 	[STM32MP1_SHRES_MDMA] = "MDMA",
66 	[STM32MP1_SHRES_PLL3] = "PLL3",
67 };
68 
shres2str_id(enum stm32mp_shres id)69 static const char __unused *shres2str_id(enum stm32mp_shres id)
70 {
71 	assert(id < ARRAY_SIZE(shres2str_id_tbl));
72 
73 	return shres2str_id_tbl[id];
74 }
75 
76 static const char __unused *shres2str_state_tbl[] = {
77 	[SHRES_UNREGISTERED] = "unregistered",
78 	[SHRES_NON_SECURE] = "non-secure",
79 	[SHRES_SECURE] = "secure",
80 };
81 
shres2str_state(unsigned int state)82 static const char __unused *shres2str_state(unsigned int state)
83 {
84 	assert(state < ARRAY_SIZE(shres2str_state_tbl));
85 
86 	return shres2str_state_tbl[state];
87 }
88 
89 /* Get resource state: these accesses lock the registering support */
lock_registering(void)90 static void lock_registering(void)
91 {
92 	registering_locked = true;
93 }
94 
periph_is_non_secure(enum stm32mp_shres id)95 static bool periph_is_non_secure(enum stm32mp_shres id)
96 {
97 	lock_registering();
98 
99 	return (shres_state[id] == SHRES_NON_SECURE) ||
100 	       (shres_state[id] == SHRES_UNREGISTERED);
101 }
102 
periph_is_secure(enum stm32mp_shres id)103 static bool periph_is_secure(enum stm32mp_shres id)
104 {
105 	return !periph_is_non_secure(id);
106 }
107 
108 /* GPIOZ pin count is saved in RAM to prevent parsing FDT several times */
109 static int8_t gpioz_nbpin = -1;
110 
get_gpio_nbpin(unsigned int bank)111 static unsigned int get_gpio_nbpin(unsigned int bank)
112 {
113 	if (bank != GPIO_BANK_Z) {
114 		int count = fdt_get_gpio_bank_pin_count(bank);
115 
116 		assert((count >= 0) && ((unsigned int)count <= (GPIO_PIN_MAX + 1)));
117 
118 		return (unsigned int)count;
119 	}
120 
121 	if (gpioz_nbpin < 0) {
122 		int count = fdt_get_gpio_bank_pin_count(GPIO_BANK_Z);
123 
124 		assert((count == 0) || (count == STM32MP_GPIOZ_PIN_MAX_COUNT));
125 
126 		gpioz_nbpin = count;
127 	}
128 
129 	return (unsigned int)gpioz_nbpin;
130 }
131 
get_gpioz_nbpin(void)132 static unsigned int get_gpioz_nbpin(void)
133 {
134 	return get_gpio_nbpin(GPIO_BANK_Z);
135 }
136 
register_periph(enum stm32mp_shres id,unsigned int state)137 static void register_periph(enum stm32mp_shres id, unsigned int state)
138 {
139 	assert((id < STM32MP1_SHRES_COUNT) &&
140 	       ((state == SHRES_SECURE) || (state == SHRES_NON_SECURE)));
141 
142 	if (registering_locked) {
143 		if (shres_state[id] == state) {
144 			return;
145 		}
146 		panic();
147 	}
148 
149 	if ((shres_state[id] != SHRES_UNREGISTERED) &&
150 	    (shres_state[id] != state)) {
151 		VERBOSE("Cannot change %s from %s to %s\n",
152 			shres2str_id(id),
153 			shres2str_state(shres_state[id]),
154 			shres2str_state(state));
155 		panic();
156 	}
157 
158 	if (shres_state[id] == SHRES_UNREGISTERED) {
159 		VERBOSE("Register %s as %s\n",
160 			shres2str_id(id), shres2str_state(state));
161 	}
162 
163 	if ((id >= STM32MP1_SHRES_GPIOZ(0)) &&
164 	    (id <= STM32MP1_SHRES_GPIOZ(7)) &&
165 	    ((unsigned int)(id - STM32MP1_SHRES_GPIOZ(0)) >= get_gpioz_nbpin())) {
166 		ERROR("Invalid GPIO pin %d, %u pin(s) available\n",
167 		      (int)(id - STM32MP1_SHRES_GPIOZ(0)), get_gpioz_nbpin());
168 		panic();
169 	}
170 
171 	shres_state[id] = (uint8_t)state;
172 
173 	/* Explore clock tree to lock dependencies */
174 	if (state == SHRES_SECURE) {
175 		enum stm32mp_shres clock_res_id;
176 
177 		switch (id) {
178 		case STM32MP1_SHRES_GPIOZ(0):
179 		case STM32MP1_SHRES_GPIOZ(1):
180 		case STM32MP1_SHRES_GPIOZ(2):
181 		case STM32MP1_SHRES_GPIOZ(3):
182 		case STM32MP1_SHRES_GPIOZ(4):
183 		case STM32MP1_SHRES_GPIOZ(5):
184 		case STM32MP1_SHRES_GPIOZ(6):
185 		case STM32MP1_SHRES_GPIOZ(7):
186 			clock_res_id = GPIOZ;
187 			break;
188 		case STM32MP1_SHRES_IWDG1:
189 			clock_res_id = IWDG1;
190 			break;
191 		case STM32MP1_SHRES_USART1:
192 			clock_res_id = USART1_K;
193 			break;
194 		case STM32MP1_SHRES_SPI6:
195 			clock_res_id = SPI6_K;
196 			break;
197 		case STM32MP1_SHRES_I2C4:
198 			clock_res_id = I2C4_K;
199 			break;
200 		case STM32MP1_SHRES_RNG1:
201 			clock_res_id = RNG1_K;
202 			break;
203 		case STM32MP1_SHRES_HASH1:
204 			clock_res_id = HASH1;
205 			break;
206 		case STM32MP1_SHRES_CRYP1:
207 			clock_res_id = CRYP1;
208 			break;
209 		case STM32MP1_SHRES_I2C6:
210 			clock_res_id = I2C6_K;
211 			break;
212 		case STM32MP1_SHRES_RTC:
213 			clock_res_id = RTC;
214 			break;
215 		default:
216 			/* No clock resource dependency */
217 			return;
218 		}
219 
220 		stm32mp1_register_clock_parents_secure(clock_res_id);
221 	}
222 }
223 
224 /* Register resource by ID */
stm32mp_register_secure_periph(enum stm32mp_shres id)225 void stm32mp_register_secure_periph(enum stm32mp_shres id)
226 {
227 	register_periph(id, SHRES_SECURE);
228 }
229 
stm32mp_register_non_secure_periph(enum stm32mp_shres id)230 void stm32mp_register_non_secure_periph(enum stm32mp_shres id)
231 {
232 	register_periph(id, SHRES_NON_SECURE);
233 }
234 
register_periph_iomem(uintptr_t base,unsigned int state)235 static void register_periph_iomem(uintptr_t base, unsigned int state)
236 {
237 	enum stm32mp_shres id;
238 
239 	switch (base) {
240 	case CRYP1_BASE:
241 		id = STM32MP1_SHRES_CRYP1;
242 		break;
243 	case HASH1_BASE:
244 		id = STM32MP1_SHRES_HASH1;
245 		break;
246 	case I2C4_BASE:
247 		id = STM32MP1_SHRES_I2C4;
248 		break;
249 	case I2C6_BASE:
250 		id = STM32MP1_SHRES_I2C6;
251 		break;
252 	case IWDG1_BASE:
253 		id = STM32MP1_SHRES_IWDG1;
254 		break;
255 	case RNG1_BASE:
256 		id = STM32MP1_SHRES_RNG1;
257 		break;
258 	case RTC_BASE:
259 		id = STM32MP1_SHRES_RTC;
260 		break;
261 	case SPI6_BASE:
262 		id = STM32MP1_SHRES_SPI6;
263 		break;
264 	case USART1_BASE:
265 		id = STM32MP1_SHRES_USART1;
266 		break;
267 
268 	case GPIOA_BASE:
269 	case GPIOB_BASE:
270 	case GPIOC_BASE:
271 	case GPIOD_BASE:
272 	case GPIOE_BASE:
273 	case GPIOF_BASE:
274 	case GPIOG_BASE:
275 	case GPIOH_BASE:
276 	case GPIOI_BASE:
277 	case GPIOJ_BASE:
278 	case GPIOK_BASE:
279 	case USART2_BASE:
280 	case USART3_BASE:
281 	case UART4_BASE:
282 	case UART5_BASE:
283 	case USART6_BASE:
284 	case UART7_BASE:
285 	case UART8_BASE:
286 	case IWDG2_BASE:
287 		/* Allow drivers to register some non-secure resources */
288 		VERBOSE("IO for non-secure resource 0x%x\n",
289 			(unsigned int)base);
290 		if (state != SHRES_NON_SECURE) {
291 			panic();
292 		}
293 
294 		return;
295 
296 	default:
297 		panic();
298 	}
299 
300 	register_periph(id, state);
301 }
302 
stm32mp_register_secure_periph_iomem(uintptr_t base)303 void stm32mp_register_secure_periph_iomem(uintptr_t base)
304 {
305 	register_periph_iomem(base, SHRES_SECURE);
306 }
307 
stm32mp_register_non_secure_periph_iomem(uintptr_t base)308 void stm32mp_register_non_secure_periph_iomem(uintptr_t base)
309 {
310 	register_periph_iomem(base, SHRES_NON_SECURE);
311 }
312 
stm32mp_register_secure_gpio(unsigned int bank,unsigned int pin)313 void stm32mp_register_secure_gpio(unsigned int bank, unsigned int pin)
314 {
315 	switch (bank) {
316 	case GPIO_BANK_Z:
317 		register_periph(STM32MP1_SHRES_GPIOZ(pin), SHRES_SECURE);
318 		break;
319 	default:
320 		ERROR("GPIO bank %u cannot be secured\n", bank);
321 		panic();
322 	}
323 }
324 
stm32mp_register_non_secure_gpio(unsigned int bank,unsigned int pin)325 void stm32mp_register_non_secure_gpio(unsigned int bank, unsigned int pin)
326 {
327 	switch (bank) {
328 	case GPIO_BANK_Z:
329 		register_periph(STM32MP1_SHRES_GPIOZ(pin), SHRES_NON_SECURE);
330 		break;
331 	default:
332 		break;
333 	}
334 }
335 
stm32mp_gpio_bank_is_non_secure(unsigned int bank)336 static bool stm32mp_gpio_bank_is_non_secure(unsigned int bank)
337 {
338 	unsigned int non_secure = 0U;
339 	unsigned int i;
340 
341 	lock_registering();
342 
343 	if (bank != GPIO_BANK_Z) {
344 		return true;
345 	}
346 
347 	for (i = 0U; i < get_gpioz_nbpin(); i++) {
348 		if (periph_is_non_secure(STM32MP1_SHRES_GPIOZ(i))) {
349 			non_secure++;
350 		}
351 	}
352 
353 	return non_secure == get_gpioz_nbpin();
354 }
355 
stm32mp_gpio_bank_is_secure(unsigned int bank)356 static bool stm32mp_gpio_bank_is_secure(unsigned int bank)
357 {
358 	unsigned int secure = 0U;
359 	unsigned int i;
360 
361 	lock_registering();
362 
363 	if (bank != GPIO_BANK_Z) {
364 		return false;
365 	}
366 
367 	for (i = 0U; i < get_gpioz_nbpin(); i++) {
368 		if (periph_is_secure(STM32MP1_SHRES_GPIOZ(i))) {
369 			secure++;
370 		}
371 	}
372 
373 	return secure == get_gpioz_nbpin();
374 }
375 
stm32mp_nsec_can_access_clock(unsigned long clock_id)376 bool stm32mp_nsec_can_access_clock(unsigned long clock_id)
377 {
378 	enum stm32mp_shres shres_id = STM32MP1_SHRES_COUNT;
379 
380 	switch (clock_id) {
381 	case CK_CSI:
382 	case CK_HSE:
383 	case CK_HSE_DIV2:
384 	case CK_HSI:
385 	case CK_LSE:
386 	case CK_LSI:
387 	case PLL1_P:
388 	case PLL1_Q:
389 	case PLL1_R:
390 	case PLL2_P:
391 	case PLL2_Q:
392 	case PLL2_R:
393 	case PLL3_P:
394 	case PLL3_Q:
395 	case PLL3_R:
396 	case RTCAPB:
397 		return true;
398 	case GPIOZ:
399 		/* Allow clock access if at least one pin is non-secure */
400 		return !stm32mp_gpio_bank_is_secure(GPIO_BANK_Z);
401 	case CRYP1:
402 		shres_id = STM32MP1_SHRES_CRYP1;
403 		break;
404 	case HASH1:
405 		shres_id = STM32MP1_SHRES_HASH1;
406 		break;
407 	case I2C4_K:
408 		shres_id = STM32MP1_SHRES_I2C4;
409 		break;
410 	case I2C6_K:
411 		shres_id = STM32MP1_SHRES_I2C6;
412 		break;
413 	case IWDG1:
414 		shres_id = STM32MP1_SHRES_IWDG1;
415 		break;
416 	case RNG1_K:
417 		shres_id = STM32MP1_SHRES_RNG1;
418 		break;
419 	case RTC:
420 		shres_id = STM32MP1_SHRES_RTC;
421 		break;
422 	case SPI6_K:
423 		shres_id = STM32MP1_SHRES_SPI6;
424 		break;
425 	case USART1_K:
426 		shres_id = STM32MP1_SHRES_USART1;
427 		break;
428 	default:
429 		return false;
430 	}
431 
432 	return periph_is_non_secure(shres_id);
433 }
434 
stm32mp_nsec_can_access_reset(unsigned int reset_id)435 bool stm32mp_nsec_can_access_reset(unsigned int reset_id)
436 {
437 	enum stm32mp_shres shres_id = STM32MP1_SHRES_COUNT;
438 
439 	switch (reset_id) {
440 	case CRYP1_R:
441 		shres_id = STM32MP1_SHRES_CRYP1;
442 		break;
443 	case GPIOZ_R:
444 		/* GPIOZ reset mandates all pins are non-secure */
445 		return stm32mp_gpio_bank_is_non_secure(GPIO_BANK_Z);
446 	case HASH1_R:
447 		shres_id = STM32MP1_SHRES_HASH1;
448 		break;
449 	case I2C4_R:
450 		shres_id = STM32MP1_SHRES_I2C4;
451 		break;
452 	case I2C6_R:
453 		shres_id = STM32MP1_SHRES_I2C6;
454 		break;
455 	case MCU_R:
456 		shres_id = STM32MP1_SHRES_MCU;
457 		break;
458 	case MDMA_R:
459 		shres_id = STM32MP1_SHRES_MDMA;
460 		break;
461 	case RNG1_R:
462 		shres_id = STM32MP1_SHRES_RNG1;
463 		break;
464 	case SPI6_R:
465 		shres_id = STM32MP1_SHRES_SPI6;
466 		break;
467 	case USART1_R:
468 		shres_id = STM32MP1_SHRES_USART1;
469 		break;
470 	default:
471 		return false;
472 	}
473 
474 	return periph_is_non_secure(shres_id);
475 }
476 
mckprot_protects_periph(enum stm32mp_shres id)477 static bool mckprot_protects_periph(enum stm32mp_shres id)
478 {
479 	switch (id) {
480 	case STM32MP1_SHRES_MCU:
481 	case STM32MP1_SHRES_PLL3:
482 		return true;
483 	default:
484 		return false;
485 	}
486 }
487 
488 /* ETZPC configuration at drivers initialization completion */
shres2decprot_attr(enum stm32mp_shres id)489 static enum etzpc_decprot_attributes shres2decprot_attr(enum stm32mp_shres id)
490 {
491 	assert((id < STM32MP1_SHRES_GPIOZ(0)) ||
492 	       (id > STM32MP1_SHRES_GPIOZ(7)));
493 
494 	if (periph_is_non_secure(id)) {
495 		return ETZPC_DECPROT_NS_RW;
496 	}
497 
498 	return ETZPC_DECPROT_S_RW;
499 }
500 
set_etzpc_secure_configuration(void)501 static void set_etzpc_secure_configuration(void)
502 {
503 	/* Some system peripherals shall be secure */
504 	etzpc_configure_decprot(STM32MP1_ETZPC_STGENC_ID, ETZPC_DECPROT_S_RW);
505 	etzpc_configure_decprot(STM32MP1_ETZPC_BKPSRAM_ID, ETZPC_DECPROT_S_RW);
506 	etzpc_configure_decprot(STM32MP1_ETZPC_DDRCTRL_ID,
507 				ETZPC_DECPROT_NS_R_S_W);
508 	etzpc_configure_decprot(STM32MP1_ETZPC_DDRPHYC_ID,
509 				ETZPC_DECPROT_NS_R_S_W);
510 
511 	/* Configure ETZPC with peripheral registering */
512 	etzpc_configure_decprot(STM32MP1_ETZPC_CRYP1_ID,
513 				shres2decprot_attr(STM32MP1_SHRES_CRYP1));
514 	etzpc_configure_decprot(STM32MP1_ETZPC_HASH1_ID,
515 				shres2decprot_attr(STM32MP1_SHRES_HASH1));
516 	etzpc_configure_decprot(STM32MP1_ETZPC_I2C4_ID,
517 				shres2decprot_attr(STM32MP1_SHRES_I2C4));
518 	etzpc_configure_decprot(STM32MP1_ETZPC_I2C6_ID,
519 				shres2decprot_attr(STM32MP1_SHRES_I2C6));
520 	etzpc_configure_decprot(STM32MP1_ETZPC_IWDG1_ID,
521 				shres2decprot_attr(STM32MP1_SHRES_IWDG1));
522 	etzpc_configure_decprot(STM32MP1_ETZPC_RNG1_ID,
523 				shres2decprot_attr(STM32MP1_SHRES_RNG1));
524 	etzpc_configure_decprot(STM32MP1_ETZPC_USART1_ID,
525 				shres2decprot_attr(STM32MP1_SHRES_USART1));
526 	etzpc_configure_decprot(STM32MP1_ETZPC_SPI6_ID,
527 				shres2decprot_attr(STM32MP1_SHRES_SPI6));
528 }
529 
check_rcc_secure_configuration(void)530 static void check_rcc_secure_configuration(void)
531 {
532 	uint32_t n;
533 	uint32_t error = 0U;
534 	bool mckprot = stm32mp1_rcc_is_mckprot();
535 	bool secure = stm32mp1_rcc_is_secure();
536 
537 	for (n = 0U; n < ARRAY_SIZE(shres_state); n++) {
538 		if (shres_state[n] != SHRES_SECURE) {
539 			continue;
540 		}
541 
542 		if (!secure || (mckprot_protects_periph(n) && (!mckprot))) {
543 			ERROR("RCC %s MCKPROT %s and %s secure\n",
544 			      secure ? "secure" : "non-secure",
545 			      mckprot ? "set" : "not set",
546 			      shres2str_id(n));
547 			error++;
548 		}
549 	}
550 
551 	if (error != 0U) {
552 		panic();
553 	}
554 }
555 
set_gpio_secure_configuration(void)556 static void set_gpio_secure_configuration(void)
557 {
558 	uint32_t pin;
559 
560 	for (pin = 0U; pin < get_gpioz_nbpin(); pin++) {
561 		bool secure_state = periph_is_secure(STM32MP1_SHRES_GPIOZ(pin));
562 
563 		set_gpio_secure_cfg(GPIO_BANK_Z, pin, secure_state);
564 	}
565 }
566 
print_shared_resources_state(void)567 static void print_shared_resources_state(void)
568 {
569 	unsigned int id;
570 
571 	for (id = 0U; id < STM32MP1_SHRES_COUNT; id++) {
572 		switch (shres_state[id]) {
573 		case SHRES_SECURE:
574 			INFO("stm32mp1 %s is secure\n", shres2str_id(id));
575 			break;
576 		case SHRES_NON_SECURE:
577 		case SHRES_UNREGISTERED:
578 			VERBOSE("stm32mp %s is non-secure\n", shres2str_id(id));
579 			break;
580 		default:
581 			VERBOSE("stm32mp %s is invalid\n", shres2str_id(id));
582 			panic();
583 		}
584 	}
585 }
586 
stm32mp_lock_periph_registering(void)587 void stm32mp_lock_periph_registering(void)
588 {
589 	registering_locked = true;
590 
591 	print_shared_resources_state();
592 
593 	check_rcc_secure_configuration();
594 	set_etzpc_secure_configuration();
595 	set_gpio_secure_configuration();
596 }
597