xref: /optee_os/core/drivers/imx/dcp/dcp.c (revision 45fecab081173ef58b1cb14b6ddf6892b0b9d3f6)
1 // SPDX-License-Identifier: BSD-2-Clause
2 /*
3  * Copyright 2020 NXP
4  */
5 
6 #include <config.h>
7 #include <dcp_utils.h>
8 #include <drivers/imx/dcp.h>
9 #include <imx-regs.h>
10 #include <io.h>
11 #include <kernel/boot.h>
12 #include <kernel/dt.h>
13 #include <kernel/mutex.h>
14 #include <kernel/spinlock.h>
15 #include <libfdt.h>
16 #include <local.h>
17 #include <mm/core_memprot.h>
18 #include <tee/cache.h>
19 #include <utee_defines.h>
20 
21 static const uint8_t sha1_null_msg[] = {
22 	0xda, 0x39, 0xa3, 0xee, 0x5e, 0x6b, 0x4b, 0x0d, 0x32, 0x55,
23 	0xbf, 0xef, 0x95, 0x60, 0x18, 0x90, 0xaf, 0xd8, 0x07, 0x09,
24 };
25 
26 static const uint8_t sha256_null_msg[] = {
27 	0xe3, 0xb0, 0xc4, 0x42, 0x98, 0xfc, 0x1c, 0x14, 0x9a, 0xfb, 0xf4,
28 	0xc8, 0x99, 0x6f, 0xb9, 0x24, 0x27, 0xae, 0x41, 0xe4, 0x64, 0x9b,
29 	0x93, 0x4c, 0xa4, 0x95, 0x99, 0x1b, 0x78, 0x52, 0xb8, 0x55,
30 };
31 
32 static vaddr_t dcp_base;
33 static bool driver_initialized;
34 static unsigned int clk_refcount;
35 static unsigned int key_store_spinlock = SPINLOCK_UNLOCK;
36 static unsigned int clock_spinlock = SPINLOCK_UNLOCK;
37 static struct dcp_align_buf hw_context_buffer;
38 
39 static struct mutex lock_channel[DCP_NB_CHANNELS] = {
40 	[DCP_CHANN0] = MUTEX_INITIALIZER,
41 	[DCP_CHANN1] = MUTEX_INITIALIZER,
42 	[DCP_CHANN2] = MUTEX_INITIALIZER,
43 	[DCP_CHANN3] = MUTEX_INITIALIZER,
44 };
45 
46 static const struct dcp_hashalg hash_alg[2] = {
47 	[DCP_SHA1] = {
48 		.type = DCP_CONTROL1_HASH_SELECT_SHA1,
49 		.size = TEE_SHA1_HASH_SIZE,
50 	},
51 	[DCP_SHA256] = {
52 		.type = DCP_CONTROL1_HASH_SELECT_SHA256,
53 		.size = TEE_SHA256_HASH_SIZE,
54 	},
55 };
56 
57 /*
58  * Enable/disable DCP clock.
59  *
60  * @enable   Enable the clock if true, disable if false.
61  */
62 static void dcp_clk_enable(bool enable)
63 {
64 	vaddr_t ccm_base = core_mmu_get_va(CCM_BASE, MEM_AREA_IO_SEC,
65 					   CCM_CCGR0 + sizeof(uint32_t));
66 	uint32_t clock_except = cpu_spin_lock_xsave(&clock_spinlock);
67 
68 	if (enable) {
69 		if (clk_refcount > 0) {
70 			clk_refcount++;
71 			goto out;
72 		} else {
73 			clk_refcount++;
74 			io_setbits32(ccm_base + CCM_CCGR0, DCP_CLK_ENABLE_MASK);
75 		}
76 	} else {
77 		assert(clk_refcount != 0);
78 
79 		clk_refcount--;
80 		if (clk_refcount > 0)
81 			goto out;
82 		else
83 			io_clrbits32(ccm_base + CCM_CCGR0, DCP_CLK_ENABLE_MASK);
84 	}
85 out:
86 	cpu_spin_unlock_xrestore(&clock_spinlock, clock_except);
87 }
88 
89 /*
90  * Lock the given channel with a mutex.
91  *
92  * @chan   DCP channel to lock
93  */
94 static TEE_Result dcp_lock_known_channel(enum dcp_channel chan)
95 {
96 	if (mutex_trylock(&lock_channel[chan]))
97 		return TEE_SUCCESS;
98 	else
99 		return TEE_ERROR_BUSY;
100 }
101 
102 /*
103  * Lock a DCP channel
104  *
105  * @channel    Pointer on operation channel parameter
106  */
107 static TEE_Result dcp_lock_channel(enum dcp_channel *channel)
108 {
109 	TEE_Result ret = TEE_ERROR_BUSY;
110 	enum dcp_channel chan = DCP_CHANN0;
111 
112 	for (chan = DCP_CHANN0; chan < DCP_NB_CHANNELS; chan++) {
113 		ret = dcp_lock_known_channel(chan);
114 		if (ret == TEE_SUCCESS) {
115 			*channel = chan;
116 			return ret;
117 		}
118 	}
119 
120 	EMSG("All channels are busy");
121 
122 	return ret;
123 }
124 
125 /*
126  * Unlock the given channel.
127  *
128  * @chan   DCP channel to unlock
129  */
130 static void dcp_unlock_channel(enum dcp_channel chan)
131 {
132 	mutex_unlock(&lock_channel[chan]);
133 }
134 
135 /*
136  * Start the DCP operation.
137  *
138  * @dcp_data   Structure containing dcp_descriptor configuration and channel to
139  *	       use.
140  */
141 static TEE_Result dcp_run(struct dcp_data *dcp_data)
142 {
143 	TEE_Result ret = TEE_SUCCESS;
144 	unsigned int timeout = 0;
145 	uint32_t val = 0;
146 
147 	dcp_data->desc.next = 0;
148 	cache_operation(TEE_CACHEFLUSH, &dcp_data->desc,
149 			sizeof(dcp_data->desc));
150 
151 	/* Enable clock if it's not done */
152 	dcp_clk_enable(true);
153 
154 	/* Clear DCP_STAT IRQ field for the channel used by the operation */
155 	io_clrbits32(dcp_base + DCP_STAT, BIT32(dcp_data->channel));
156 
157 	/* Clear CH_N_STAT to clear IRQ and error codes */
158 	io_write32(dcp_base + DCP_CH_N_STAT(dcp_data->channel), 0x0);
159 
160 	/* Update descriptor structure to be processed for the channel */
161 	io_write32(dcp_base + DCP_CH_N_CMDPTR(dcp_data->channel),
162 		   virt_to_phys(&dcp_data->desc));
163 
164 	/* Increment the semaphore to start the transfer */
165 	io_write32(dcp_base + DCP_CH_N_SEMA(dcp_data->channel), 0x1);
166 
167 	for (timeout = 0; timeout < DCP_MAX_TIMEOUT; timeout++) {
168 		dcp_udelay(10);
169 		val = io_read32(dcp_base + DCP_STAT);
170 		if (val & BIT(dcp_data->channel))
171 			break;
172 	}
173 
174 	if (timeout == DCP_MAX_TIMEOUT) {
175 		EMSG("Timeout elapsed before operation");
176 		ret = TEE_ERROR_GENERIC;
177 		goto out;
178 	}
179 
180 	val = io_read32(dcp_base + DCP_CH_N_STAT(dcp_data->channel));
181 	if (val & DCP_CH_STAT_ERROR_MASK) {
182 		EMSG("Error operation, 0x%" PRIx32, val);
183 		ret = TEE_ERROR_GENERIC;
184 	}
185 
186 out:
187 	dcp_clk_enable(false);
188 
189 	return ret;
190 }
191 
192 static TEE_Result dcp_cmac_subkey_generation(struct dcp_cipher_init *init,
193 					     uint8_t *k1, uint8_t *k2)
194 {
195 	TEE_Result ret = TEE_ERROR_GENERIC;
196 	struct dcp_cipher_data data = { };
197 	uint8_t l[16] = { };
198 	uint8_t tmp[16] = { };
199 	uint8_t const_zero[16] = { };
200 	uint8_t const_rb[16] = { [15] = 0x87 };
201 
202 	ret = dcp_cipher_do_init(&data, init);
203 	if (ret != TEE_SUCCESS)
204 		return ret;
205 
206 	ret = dcp_cipher_do_update(&data, const_zero, l, sizeof(l));
207 	if (ret != TEE_SUCCESS)
208 		goto out;
209 
210 	if ((l[0] & BIT(7)) == 0) {
211 		dcp_left_shift_buffer(l, k1, 16);
212 	} else {
213 		dcp_left_shift_buffer(l, tmp, 16);
214 		dcp_xor(tmp, const_rb, k1, 16);
215 	}
216 
217 	if ((k1[0] & BIT(7)) == 0) {
218 		dcp_left_shift_buffer(k1, k2, 16);
219 	} else {
220 		dcp_left_shift_buffer(k1, tmp, 16);
221 		dcp_xor(tmp, const_rb, k2, 16);
222 	}
223 
224 	ret = TEE_SUCCESS;
225 out:
226 	dcp_cipher_do_final(&data);
227 
228 	return ret;
229 }
230 
231 TEE_Result dcp_store_key(uint32_t *key, unsigned int index)
232 {
233 	uint32_t val = 0;
234 	unsigned int i = 0;
235 	uint32_t key_store_except = 0;
236 
237 	if (!key)
238 		return TEE_ERROR_BAD_PARAMETERS;
239 
240 	if (index > DCP_SRAM_KEY_NB_SUBWORD - 1) {
241 		EMSG("Bad parameters, index must be < %u",
242 		     DCP_SRAM_KEY_NB_SUBWORD);
243 		return TEE_ERROR_BAD_PARAMETERS;
244 	}
245 
246 	key_store_except = cpu_spin_lock_xsave(&key_store_spinlock);
247 
248 	dcp_clk_enable(true);
249 
250 	val = DCP_SRAM_KEY_INDEX(index);
251 	io_write32(dcp_base + DCP_KEY, val);
252 
253 	/*
254 	 * Key is stored as four uint32 values, starting with subword0
255 	 * (least-significant word)
256 	 */
257 	for (i = 0; i < DCP_SRAM_KEY_NB_SUBWORD; i++) {
258 		val = TEE_U32_TO_BIG_ENDIAN(key[i]);
259 		io_write32(dcp_base + DCP_KEYDATA, val);
260 	}
261 
262 	dcp_clk_enable(false);
263 
264 	cpu_spin_unlock_xrestore(&key_store_spinlock, key_store_except);
265 
266 	return TEE_SUCCESS;
267 }
268 
269 TEE_Result dcp_cmac(struct dcp_cipher_init *init, uint8_t *input,
270 		    size_t input_size, uint8_t *output)
271 {
272 	TEE_Result ret = TEE_ERROR_GENERIC;
273 	uint8_t key1[DCP_AES128_KEY_SIZE] = { };
274 	uint8_t key2[DCP_AES128_KEY_SIZE] = { };
275 	unsigned int nb_blocks = 0;
276 	bool block_complete = false;
277 	struct dcp_cipher_data data = { };
278 	uint8_t y[DCP_AES128_BLOCK_SIZE] = { };
279 	uint8_t x[DCP_AES128_BLOCK_SIZE] = { };
280 	uint8_t last[DCP_AES128_BLOCK_SIZE] = { };
281 	unsigned int i = 0;
282 	uint8_t offset = 0;
283 
284 	if (!output || !init)
285 		return TEE_ERROR_BAD_PARAMETERS;
286 
287 	if (!input && input_size)
288 		return TEE_ERROR_BAD_PARAMETERS;
289 
290 	ret = dcp_cipher_do_init(&data, init);
291 	if (ret != TEE_SUCCESS) {
292 		ret = TEE_ERROR_OUT_OF_MEMORY;
293 		goto out;
294 	}
295 
296 	/* Generate CMAC subkeys */
297 	ret = dcp_cmac_subkey_generation(init, key1, key2);
298 	if (ret != TEE_SUCCESS)
299 		goto out;
300 
301 	/* Get number of block */
302 	nb_blocks = ROUNDUP_DIV(input_size, DCP_AES128_BLOCK_SIZE);
303 
304 	block_complete = nb_blocks && !(input_size % DCP_AES128_BLOCK_SIZE);
305 	if (nb_blocks == 0)
306 		nb_blocks = 1;
307 
308 	for (i = 0; i < nb_blocks - 1; i++) {
309 		dcp_xor(x, input + offset, y, DCP_AES128_BLOCK_SIZE);
310 		ret = dcp_cipher_do_update(&data, y, x,
311 					   DCP_AES128_BLOCK_SIZE);
312 		if (ret)
313 			goto out;
314 		offset += DCP_AES128_BLOCK_SIZE;
315 	}
316 
317 	/* Process the last block */
318 	memcpy(last, input + offset, input_size - offset);
319 
320 	if (block_complete) {
321 		dcp_xor(last, key1, last, DCP_AES128_BLOCK_SIZE);
322 	} else {
323 		dcp_cmac_padding(last, input_size % DCP_AES128_BLOCK_SIZE);
324 		dcp_xor(last, key2, last, DCP_AES128_BLOCK_SIZE);
325 	}
326 
327 	dcp_xor(x, last, y, DCP_AES128_BLOCK_SIZE);
328 	ret = dcp_cipher_do_update(&data, y, x,
329 				   DCP_AES128_BLOCK_SIZE);
330 	if (ret)
331 		goto out;
332 
333 	memcpy(output, x, DCP_AES128_BLOCK_SIZE);
334 
335 out:
336 	dcp_cipher_do_final(&data);
337 
338 	return ret;
339 }
340 
341 TEE_Result dcp_cipher_do_init(struct dcp_cipher_data *data,
342 			      struct dcp_cipher_init *init)
343 {
344 	struct dcp_descriptor *desc = NULL;
345 	TEE_Result ret = TEE_ERROR_GENERIC;
346 
347 	if (!init || !data)
348 		return TEE_ERROR_BAD_PARAMETERS;
349 
350 	ret = dcp_lock_channel(&data->dcp_data.channel);
351 	if (ret != TEE_SUCCESS)
352 		return ret;
353 
354 	desc = &data->dcp_data.desc;
355 
356 	desc->ctrl0 = DCP_CONTROL0_DECR_SEMAPHORE | DCP_CONTROL0_ENABLE_CIPHER |
357 		      DCP_CONTROL0_INTERRUPT_ENABLE;
358 	desc->ctrl1 = DCP_CONTROL1_CIPHER_SELECT_AES128;
359 
360 	if (init->op == DCP_ENCRYPT)
361 		desc->ctrl0 |= DCP_CONTROL0_CIPHER_ENCRYPT;
362 
363 	if (init->key_mode == DCP_OTP) {
364 		desc->ctrl0 &= ~DCP_CONTROL0_OTP_KEY;
365 		desc->ctrl1 |= DCP_CONTROL1_KEY_SELECT_OTP_CRYPTO;
366 	} else if (init->key_mode == DCP_PAYLOAD) {
367 		desc->ctrl0 |= DCP_CONTROL0_PAYLOAD_KEY;
368 		if (!init->key)
369 			return TEE_ERROR_BAD_PARAMETERS;
370 		memcpy(data->key, init->key, DCP_AES128_KEY_SIZE);
371 	} else {
372 		desc->ctrl1 |= SHIFT_U32(init->key_mode, 8);
373 	}
374 
375 	if (init->mode == DCP_CBC) {
376 		desc->ctrl0 |= DCP_CONTROL0_CIPHER_INIT;
377 		desc->ctrl1 |= DCP_CONTROL1_CIPHER_MODE_CBC;
378 		if (!init->iv)
379 			return TEE_ERROR_BAD_PARAMETERS;
380 		memcpy(data->iv, init->iv, DCP_AES128_IV_SIZE);
381 	}
382 
383 	/* Allocate aligned buffer for dcp iv and key */
384 	ret = dcp_calloc_align_buf(&data->payload,
385 				   DCP_AES128_IV_SIZE + DCP_AES128_KEY_SIZE);
386 	if (ret != TEE_SUCCESS)
387 		return ret;
388 
389 	desc->src_buffer = 0;
390 	desc->dest_buffer = 0;
391 	desc->status = 0;
392 	desc->buff_size = 0;
393 	desc->next = virt_to_phys(desc);
394 
395 	data->initialized = true;
396 
397 	return ret;
398 }
399 
400 TEE_Result dcp_cipher_do_update(struct dcp_cipher_data *data,
401 				const uint8_t *src, uint8_t *dst, size_t size)
402 {
403 	TEE_Result ret = TEE_ERROR_GENERIC;
404 	struct dcp_align_buf output = { };
405 	struct dcp_align_buf input = { };
406 	struct dcp_descriptor *desc = NULL;
407 
408 	if (!data || !src || !dst)
409 		return TEE_ERROR_BAD_PARAMETERS;
410 
411 	if (!data->initialized) {
412 		EMSG("Error, please call dcp_aes_do_init() before");
413 		return TEE_ERROR_BAD_STATE;
414 	}
415 
416 	if (size % DCP_AES128_BLOCK_SIZE) {
417 		EMSG("Input size has to be a multiple of %zu bytes",
418 		     DCP_AES128_BLOCK_SIZE);
419 		return TEE_ERROR_BAD_PARAMETERS;
420 	}
421 
422 	ret = dcp_calloc_align_buf(&output, size);
423 	if (ret != TEE_SUCCESS)
424 		goto out;
425 
426 	ret = dcp_calloc_align_buf(&input, size);
427 	if (ret != TEE_SUCCESS)
428 		goto out;
429 
430 	desc = &data->dcp_data.desc;
431 
432 	/* Copy input data */
433 	memcpy(input.data, src, size);
434 
435 	/* Copy key and IV */
436 	memcpy(data->payload.data, data->key, DCP_AES128_KEY_SIZE);
437 	data->payload_size = DCP_AES128_KEY_SIZE;
438 	if (desc->ctrl0 & DCP_CONTROL0_CIPHER_INIT) {
439 		memcpy(data->payload.data + DCP_AES128_KEY_SIZE, data->iv,
440 		       DCP_AES128_IV_SIZE);
441 		data->payload_size += DCP_AES128_IV_SIZE;
442 	}
443 
444 	desc->src_buffer = input.paddr;
445 	desc->dest_buffer = output.paddr;
446 	desc->payload = data->payload.paddr;
447 	desc->buff_size = size;
448 
449 	cache_operation(TEE_CACHECLEAN, data->payload.data,
450 			data->payload_size);
451 	cache_operation(TEE_CACHECLEAN, input.data, size);
452 	cache_operation(TEE_CACHEINVALIDATE, output.data, size);
453 
454 	ret = dcp_run(&data->dcp_data);
455 	if (ret)
456 		goto out;
457 
458 	cache_operation(TEE_CACHEINVALIDATE, output.data, size);
459 
460 	desc->ctrl0 &= ~DCP_CONTROL0_CIPHER_INIT;
461 
462 	memcpy(dst, output.data, size);
463 out:
464 	dcp_free(&output);
465 	dcp_free(&input);
466 
467 	return ret;
468 }
469 
470 void dcp_cipher_do_final(struct dcp_cipher_data *data)
471 {
472 	if (data)
473 		data->initialized = false;
474 
475 	dcp_free(&data->payload);
476 	dcp_unlock_channel(data->dcp_data.channel);
477 }
478 
479 TEE_Result dcp_sha_do_init(struct dcp_hash_data *hashdata)
480 {
481 	struct dcp_descriptor *desc = NULL;
482 	TEE_Result ret = TEE_ERROR_GENERIC;
483 
484 	if (!hashdata) {
485 		EMSG("Bad parameters, hashdata is NULL");
486 		return TEE_ERROR_BAD_PARAMETERS;
487 	}
488 
489 	desc = &hashdata->dcp_data.desc;
490 
491 	/* DCP descriptor init */
492 	desc->status = 0;
493 	desc->payload = 0;
494 	desc->dest_buffer = 0;
495 	desc->ctrl0 = DCP_CONTROL0_ENABLE_HASH | DCP_CONTROL0_INTERRUPT_ENABLE |
496 		      DCP_CONTROL0_DECR_SEMAPHORE | DCP_CONTROL0_HASH_INIT;
497 	desc->ctrl1 = hash_alg[hashdata->alg].type;
498 	desc->buff_size = 0;
499 	desc->next = 0;
500 	desc->src_buffer = 0;
501 
502 	ret = dcp_lock_channel(&hashdata->dcp_data.channel);
503 	if (ret != TEE_SUCCESS) {
504 		EMSG("Channel is busy, can't start operation now");
505 		return ret;
506 	}
507 
508 	/* Allocate context data */
509 	ret = dcp_calloc_align_buf(&hashdata->ctx, DCP_SHA_BLOCK_SIZE);
510 	if (ret != TEE_SUCCESS)
511 		return ret;
512 
513 	hashdata->initialized = true;
514 	hashdata->ctx_size = 0;
515 
516 	return ret;
517 }
518 
519 TEE_Result dcp_sha_do_update(struct dcp_hash_data *hashdata,
520 			     const uint8_t *data, size_t len)
521 {
522 	TEE_Result ret = TEE_ERROR_GENERIC;
523 	struct dcp_descriptor *desc = NULL;
524 	struct dcp_align_buf input = { };
525 	uint32_t offset = 0;
526 	uint32_t nb_blocks = 0;
527 	size_t size_todo = 0;
528 	size_t size_left = 0;
529 	size_t size_total = 0;
530 
531 	if (!hashdata || !data || !len)
532 		return TEE_ERROR_BAD_PARAMETERS;
533 
534 	if (!hashdata->initialized) {
535 		EMSG("hashdata is uninitialized");
536 		return TEE_ERROR_BAD_STATE;
537 	}
538 
539 	/* Get number of blocks */
540 	if (ADD_OVERFLOW(hashdata->ctx_size, len, &size_total))
541 		return TEE_ERROR_BAD_PARAMETERS;
542 
543 	nb_blocks = size_total / DCP_SHA_BLOCK_SIZE;
544 	size_todo = nb_blocks * DCP_SHA_BLOCK_SIZE;
545 	size_left = len - size_todo + hashdata->ctx_size;
546 	desc = &hashdata->dcp_data.desc;
547 
548 	if (size_todo) {
549 		/* Allocate buffer as input */
550 		ret = dcp_calloc_align_buf(&input, size_todo);
551 		if (ret != TEE_SUCCESS)
552 			return ret;
553 
554 		/* Copy previous data if any */
555 		offset = size_todo - hashdata->ctx_size;
556 		memcpy(input.data, hashdata->ctx.data, hashdata->ctx_size);
557 		memcpy(input.data + hashdata->ctx_size, data, offset);
558 		hashdata->ctx_size = 0;
559 
560 		desc->src_buffer = input.paddr;
561 		desc->buff_size = size_todo;
562 
563 		cache_operation(TEE_CACHECLEAN, input.data, size_todo);
564 
565 		ret = dcp_run(&hashdata->dcp_data);
566 		desc->ctrl0 &= ~DCP_CONTROL0_HASH_INIT;
567 
568 		dcp_free(&input);
569 	} else {
570 		size_left = len;
571 		offset = 0;
572 		ret = TEE_SUCCESS;
573 	}
574 
575 	/* Save any data left */
576 	memcpy(hashdata->ctx.data + hashdata->ctx_size, data + offset,
577 	       size_left);
578 	hashdata->ctx_size += size_left;
579 
580 	return ret;
581 }
582 
583 TEE_Result dcp_sha_do_final(struct dcp_hash_data *hashdata, uint8_t *digest,
584 			    size_t digest_size)
585 {
586 	TEE_Result ret = TEE_ERROR_GENERIC;
587 	size_t payload_size = 0;
588 	struct dcp_descriptor *desc = NULL;
589 	struct dcp_align_buf payload = { };
590 
591 	if (!hashdata || !digest)
592 		return TEE_ERROR_BAD_PARAMETERS;
593 
594 	if (!hashdata->initialized) {
595 		EMSG("hashdata is uninitialized");
596 		return TEE_ERROR_BAD_STATE;
597 	}
598 
599 	if (digest_size < hash_alg[hashdata->alg].size) {
600 		EMSG("Digest buffer size is to small, should be %" PRId32,
601 		     hash_alg[hashdata->alg].size);
602 		return TEE_ERROR_BAD_PARAMETERS;
603 	}
604 
605 	desc = &hashdata->dcp_data.desc;
606 	payload_size = hash_alg[hashdata->alg].size;
607 
608 	/* Handle the case where the input message is NULL */
609 	if ((desc->ctrl0 & DCP_CONTROL0_HASH_INIT) && hashdata->ctx_size == 0) {
610 		if (hashdata->alg == DCP_SHA1)
611 			memcpy(digest, sha1_null_msg, payload_size);
612 		if (hashdata->alg == DCP_SHA256)
613 			memcpy(digest, sha256_null_msg, payload_size);
614 		ret = TEE_SUCCESS;
615 	} else {
616 		/* Allocate buffer for the digest */
617 		ret = dcp_calloc_align_buf(&payload, payload_size);
618 		if (ret != TEE_SUCCESS)
619 			return ret;
620 
621 		/* Set work packet for last iteration */
622 		desc->ctrl0 |= DCP_CONTROL0_HASH_TERM;
623 		desc->src_buffer = hashdata->ctx.paddr;
624 		desc->buff_size = hashdata->ctx_size;
625 		desc->payload = payload.paddr;
626 
627 		cache_operation(TEE_CACHECLEAN, hashdata->ctx.data,
628 				hashdata->ctx_size);
629 		cache_operation(TEE_CACHEINVALIDATE, payload.data,
630 				payload_size);
631 
632 		ret = dcp_run(&hashdata->dcp_data);
633 
634 		/* Copy the result */
635 		cache_operation(TEE_CACHEINVALIDATE, payload.data,
636 				payload_size);
637 		/* DCP payload result is flipped */
638 		dcp_reverse(payload.data, digest, payload_size);
639 
640 		dcp_free(&payload);
641 	}
642 
643 	dcp_free(&hashdata->ctx);
644 
645 	/* Reset hashdata strcuture */
646 	hashdata->initialized = false;
647 
648 	dcp_unlock_channel(hashdata->dcp_data.channel);
649 
650 	return ret;
651 }
652 
653 void dcp_disable_unique_key(void)
654 {
655 	dcp_clk_enable(true);
656 	io_setbits32(dcp_base + DCP_CAPABILITY0,
657 		     DCP_CAPABILITY0_DISABLE_UNIQUE_KEY);
658 	dcp_clk_enable(false);
659 }
660 
661 #ifdef CFG_DT
662 static const char *const dt_ctrl_match_table[] = {
663 	"fsl,imx28-dcp",
664 	"fsl,imx6sl-dcp",
665 };
666 
667 /*
668  * Fetch DCP base address from DT
669  *
670  * @base        [out] DCP base address
671  */
672 static TEE_Result dcp_pbase(paddr_t *base)
673 {
674 	void *fdt = NULL;
675 	int node = -1;
676 	unsigned int i = 0;
677 
678 	fdt = get_dt();
679 	if (!fdt) {
680 		EMSG("DTB no present");
681 		return TEE_ERROR_ITEM_NOT_FOUND;
682 	}
683 
684 	for (i = 0; i < ARRAY_SIZE(dt_ctrl_match_table); i++) {
685 		node = fdt_node_offset_by_compatible(fdt, 0,
686 						     dt_ctrl_match_table[i]);
687 		if (node >= 0)
688 			break;
689 	}
690 
691 	if (node < 0) {
692 		EMSG("DCP node not found err = %d", node);
693 		return TEE_ERROR_ITEM_NOT_FOUND;
694 	}
695 
696 	if (fdt_get_status(fdt, node) == DT_STATUS_DISABLED)
697 		return TEE_ERROR_ITEM_NOT_FOUND;
698 
699 	/* Force secure-status = "okay" and status="disabled" */
700 	if (dt_enable_secure_status(fdt, node)) {
701 		EMSG("Not able to set DCP Control DTB entry secure");
702 		return TEE_ERROR_NOT_SUPPORTED;
703 	}
704 
705 	*base = fdt_reg_base_address(fdt, node);
706 	if (*base == DT_INFO_INVALID_REG) {
707 		EMSG("Unable to get the DCP Base address");
708 		return TEE_ERROR_ITEM_NOT_FOUND;
709 	}
710 
711 	return TEE_SUCCESS;
712 }
713 #endif /* CFG_DT */
714 
715 TEE_Result dcp_init(void)
716 {
717 	TEE_Result ret = TEE_ERROR_GENERIC;
718 	paddr_t pbase = 0;
719 
720 	if (driver_initialized)
721 		return TEE_SUCCESS;
722 
723 	dcp_clk_enable(true);
724 
725 	ret = dcp_pbase(&pbase);
726 	if (ret != TEE_SUCCESS)
727 		pbase = DCP_BASE;
728 
729 	dcp_base = core_mmu_get_va(pbase, MEM_AREA_IO_SEC, DCP_CONTEXT +
730 				   sizeof(uint32_t));
731 	if (!dcp_base) {
732 		EMSG("Unable to get DCP physical address");
733 		return TEE_ERROR_ITEM_NOT_FOUND;
734 	}
735 
736 	/* Context switching buffer memory allocation */
737 	ret = dcp_calloc_align_buf(&hw_context_buffer, DCP_CONTEXT_BUFFER_SIZE);
738 	if (ret != TEE_SUCCESS) {
739 		EMSG("hw_context_buffer allocation failed");
740 		return ret;
741 	}
742 
743 	/*
744 	 * Reset the DCP before initialization. Depending on the SoC lifecycle
745 	 * state, the DCP needs to be reset to reload the OTP master key from
746 	 * the SNVS.
747 	 */
748 	io_write32(dcp_base + DCP_CTRL_SET, DCP_CTRL_SFTRST | DCP_CTRL_CLKGATE);
749 
750 	/*
751 	 * Initialize control register.
752 	 * Enable normal DCP operation (SFTRST & CLKGATE bits set to 0)
753 	 */
754 	io_write32(dcp_base + DCP_CTRL_CLR, DCP_CTRL_SFTRST | DCP_CTRL_CLKGATE);
755 
756 	io_write32(dcp_base + DCP_CTRL_SET,
757 		   DCP_CTRL_GATHER_RESIDUAL_WRITES |
758 			   DCP_CTRL_ENABLE_CONTEXT_SWITCHING);
759 
760 	/* Enable all DCP channels */
761 	io_write32(dcp_base + DCP_CHANNELCTRL,
762 		   DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK);
763 
764 	/* Clear DCP_STAT register */
765 	io_write32(dcp_base + DCP_STAT_CLR, DCP_STAT_CLEAR);
766 
767 	/* Copy context switching buffer address in DCP_CONTEXT register */
768 	io_write32(dcp_base + DCP_CONTEXT, (uint32_t)hw_context_buffer.paddr);
769 
770 	driver_initialized = true;
771 
772 	dcp_clk_enable(false);
773 
774 	return ret;
775 }
776