xref: /linux/drivers/crypto/img-hash.c (revision 60684c2bd35064043360e6f716d1b7c20e967b7d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) 2014 Imagination Technologies
4  * Authors:  Will Thomas, James Hartley
5  *
6  *	Interface structure taken from omap-sham driver
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/dmaengine.h>
12 #include <linux/interrupt.h>
13 #include <linux/io.h>
14 #include <linux/kernel.h>
15 #include <linux/module.h>
16 #include <linux/of_device.h>
17 #include <linux/platform_device.h>
18 #include <linux/scatterlist.h>
19 
20 #include <crypto/internal/hash.h>
21 #include <crypto/md5.h>
22 #include <crypto/sha1.h>
23 #include <crypto/sha2.h>
24 
25 #define CR_RESET			0
26 #define CR_RESET_SET			1
27 #define CR_RESET_UNSET			0
28 
29 #define CR_MESSAGE_LENGTH_H		0x4
30 #define CR_MESSAGE_LENGTH_L		0x8
31 
32 #define CR_CONTROL			0xc
33 #define CR_CONTROL_BYTE_ORDER_3210	0
34 #define CR_CONTROL_BYTE_ORDER_0123	1
35 #define CR_CONTROL_BYTE_ORDER_2310	2
36 #define CR_CONTROL_BYTE_ORDER_1032	3
37 #define CR_CONTROL_BYTE_ORDER_SHIFT	8
38 #define CR_CONTROL_ALGO_MD5	0
39 #define CR_CONTROL_ALGO_SHA1	1
40 #define CR_CONTROL_ALGO_SHA224	2
41 #define CR_CONTROL_ALGO_SHA256	3
42 
43 #define CR_INTSTAT			0x10
44 #define CR_INTENAB			0x14
45 #define CR_INTCLEAR			0x18
46 #define CR_INT_RESULTS_AVAILABLE	BIT(0)
47 #define CR_INT_NEW_RESULTS_SET		BIT(1)
48 #define CR_INT_RESULT_READ_ERR		BIT(2)
49 #define CR_INT_MESSAGE_WRITE_ERROR	BIT(3)
50 #define CR_INT_STATUS			BIT(8)
51 
52 #define CR_RESULT_QUEUE		0x1c
53 #define CR_RSD0				0x40
54 #define CR_CORE_REV			0x50
55 #define CR_CORE_DES1		0x60
56 #define CR_CORE_DES2		0x70
57 
58 #define DRIVER_FLAGS_BUSY		BIT(0)
59 #define DRIVER_FLAGS_FINAL		BIT(1)
60 #define DRIVER_FLAGS_DMA_ACTIVE		BIT(2)
61 #define DRIVER_FLAGS_OUTPUT_READY	BIT(3)
62 #define DRIVER_FLAGS_INIT		BIT(4)
63 #define DRIVER_FLAGS_CPU		BIT(5)
64 #define DRIVER_FLAGS_DMA_READY		BIT(6)
65 #define DRIVER_FLAGS_ERROR		BIT(7)
66 #define DRIVER_FLAGS_SG			BIT(8)
67 #define DRIVER_FLAGS_SHA1		BIT(18)
68 #define DRIVER_FLAGS_SHA224		BIT(19)
69 #define DRIVER_FLAGS_SHA256		BIT(20)
70 #define DRIVER_FLAGS_MD5		BIT(21)
71 
72 #define IMG_HASH_QUEUE_LENGTH		20
73 #define IMG_HASH_DMA_BURST		4
74 #define IMG_HASH_DMA_THRESHOLD		64
75 
76 #ifdef __LITTLE_ENDIAN
77 #define IMG_HASH_BYTE_ORDER		CR_CONTROL_BYTE_ORDER_3210
78 #else
79 #define IMG_HASH_BYTE_ORDER		CR_CONTROL_BYTE_ORDER_0123
80 #endif
81 
82 struct img_hash_dev;
83 
84 struct img_hash_request_ctx {
85 	struct img_hash_dev	*hdev;
86 	u8 digest[SHA256_DIGEST_SIZE] __aligned(sizeof(u32));
87 	unsigned long		flags;
88 	size_t			digsize;
89 
90 	dma_addr_t		dma_addr;
91 	size_t			dma_ct;
92 
93 	/* sg root */
94 	struct scatterlist	*sgfirst;
95 	/* walk state */
96 	struct scatterlist	*sg;
97 	size_t			nents;
98 	size_t			offset;
99 	unsigned int		total;
100 	size_t			sent;
101 
102 	unsigned long		op;
103 
104 	size_t			bufcnt;
105 	struct ahash_request	fallback_req;
106 
107 	/* Zero length buffer must remain last member of struct */
108 	u8 buffer[] __aligned(sizeof(u32));
109 };
110 
111 struct img_hash_ctx {
112 	struct img_hash_dev	*hdev;
113 	unsigned long		flags;
114 	struct crypto_ahash	*fallback;
115 };
116 
117 struct img_hash_dev {
118 	struct list_head	list;
119 	struct device		*dev;
120 	struct clk		*hash_clk;
121 	struct clk		*sys_clk;
122 	void __iomem		*io_base;
123 
124 	phys_addr_t		bus_addr;
125 	void __iomem		*cpu_addr;
126 
127 	spinlock_t		lock;
128 	int			err;
129 	struct tasklet_struct	done_task;
130 	struct tasklet_struct	dma_task;
131 
132 	unsigned long		flags;
133 	struct crypto_queue	queue;
134 	struct ahash_request	*req;
135 
136 	struct dma_chan		*dma_lch;
137 };
138 
139 struct img_hash_drv {
140 	struct list_head dev_list;
141 	spinlock_t lock;
142 };
143 
144 static struct img_hash_drv img_hash = {
145 	.dev_list = LIST_HEAD_INIT(img_hash.dev_list),
146 	.lock = __SPIN_LOCK_UNLOCKED(img_hash.lock),
147 };
148 
149 static inline u32 img_hash_read(struct img_hash_dev *hdev, u32 offset)
150 {
151 	return readl_relaxed(hdev->io_base + offset);
152 }
153 
154 static inline void img_hash_write(struct img_hash_dev *hdev,
155 				  u32 offset, u32 value)
156 {
157 	writel_relaxed(value, hdev->io_base + offset);
158 }
159 
160 static inline __be32 img_hash_read_result_queue(struct img_hash_dev *hdev)
161 {
162 	return cpu_to_be32(img_hash_read(hdev, CR_RESULT_QUEUE));
163 }
164 
165 static void img_hash_start(struct img_hash_dev *hdev, bool dma)
166 {
167 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
168 	u32 cr = IMG_HASH_BYTE_ORDER << CR_CONTROL_BYTE_ORDER_SHIFT;
169 
170 	if (ctx->flags & DRIVER_FLAGS_MD5)
171 		cr |= CR_CONTROL_ALGO_MD5;
172 	else if (ctx->flags & DRIVER_FLAGS_SHA1)
173 		cr |= CR_CONTROL_ALGO_SHA1;
174 	else if (ctx->flags & DRIVER_FLAGS_SHA224)
175 		cr |= CR_CONTROL_ALGO_SHA224;
176 	else if (ctx->flags & DRIVER_FLAGS_SHA256)
177 		cr |= CR_CONTROL_ALGO_SHA256;
178 	dev_dbg(hdev->dev, "Starting hash process\n");
179 	img_hash_write(hdev, CR_CONTROL, cr);
180 
181 	/*
182 	 * The hardware block requires two cycles between writing the control
183 	 * register and writing the first word of data in non DMA mode, to
184 	 * ensure the first data write is not grouped in burst with the control
185 	 * register write a read is issued to 'flush' the bus.
186 	 */
187 	if (!dma)
188 		img_hash_read(hdev, CR_CONTROL);
189 }
190 
191 static int img_hash_xmit_cpu(struct img_hash_dev *hdev, const u8 *buf,
192 			     size_t length, int final)
193 {
194 	u32 count, len32;
195 	const u32 *buffer = (const u32 *)buf;
196 
197 	dev_dbg(hdev->dev, "xmit_cpu:  length: %zu bytes\n", length);
198 
199 	if (final)
200 		hdev->flags |= DRIVER_FLAGS_FINAL;
201 
202 	len32 = DIV_ROUND_UP(length, sizeof(u32));
203 
204 	for (count = 0; count < len32; count++)
205 		writel_relaxed(buffer[count], hdev->cpu_addr);
206 
207 	return -EINPROGRESS;
208 }
209 
210 static void img_hash_dma_callback(void *data)
211 {
212 	struct img_hash_dev *hdev = (struct img_hash_dev *)data;
213 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
214 
215 	if (ctx->bufcnt) {
216 		img_hash_xmit_cpu(hdev, ctx->buffer, ctx->bufcnt, 0);
217 		ctx->bufcnt = 0;
218 	}
219 	if (ctx->sg)
220 		tasklet_schedule(&hdev->dma_task);
221 }
222 
223 static int img_hash_xmit_dma(struct img_hash_dev *hdev, struct scatterlist *sg)
224 {
225 	struct dma_async_tx_descriptor *desc;
226 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
227 
228 	ctx->dma_ct = dma_map_sg(hdev->dev, sg, 1, DMA_TO_DEVICE);
229 	if (ctx->dma_ct == 0) {
230 		dev_err(hdev->dev, "Invalid DMA sg\n");
231 		hdev->err = -EINVAL;
232 		return -EINVAL;
233 	}
234 
235 	desc = dmaengine_prep_slave_sg(hdev->dma_lch,
236 				       sg,
237 				       ctx->dma_ct,
238 				       DMA_MEM_TO_DEV,
239 				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
240 	if (!desc) {
241 		dev_err(hdev->dev, "Null DMA descriptor\n");
242 		hdev->err = -EINVAL;
243 		dma_unmap_sg(hdev->dev, sg, 1, DMA_TO_DEVICE);
244 		return -EINVAL;
245 	}
246 	desc->callback = img_hash_dma_callback;
247 	desc->callback_param = hdev;
248 	dmaengine_submit(desc);
249 	dma_async_issue_pending(hdev->dma_lch);
250 
251 	return 0;
252 }
253 
254 static int img_hash_write_via_cpu(struct img_hash_dev *hdev)
255 {
256 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
257 
258 	ctx->bufcnt = sg_copy_to_buffer(hdev->req->src, sg_nents(ctx->sg),
259 					ctx->buffer, hdev->req->nbytes);
260 
261 	ctx->total = hdev->req->nbytes;
262 	ctx->bufcnt = 0;
263 
264 	hdev->flags |= (DRIVER_FLAGS_CPU | DRIVER_FLAGS_FINAL);
265 
266 	img_hash_start(hdev, false);
267 
268 	return img_hash_xmit_cpu(hdev, ctx->buffer, ctx->total, 1);
269 }
270 
271 static int img_hash_finish(struct ahash_request *req)
272 {
273 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
274 
275 	if (!req->result)
276 		return -EINVAL;
277 
278 	memcpy(req->result, ctx->digest, ctx->digsize);
279 
280 	return 0;
281 }
282 
283 static void img_hash_copy_hash(struct ahash_request *req)
284 {
285 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
286 	__be32 *hash = (__be32 *)ctx->digest;
287 	int i;
288 
289 	for (i = (ctx->digsize / sizeof(*hash)) - 1; i >= 0; i--)
290 		hash[i] = img_hash_read_result_queue(ctx->hdev);
291 }
292 
293 static void img_hash_finish_req(struct ahash_request *req, int err)
294 {
295 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
296 	struct img_hash_dev *hdev =  ctx->hdev;
297 
298 	if (!err) {
299 		img_hash_copy_hash(req);
300 		if (DRIVER_FLAGS_FINAL & hdev->flags)
301 			err = img_hash_finish(req);
302 	} else {
303 		dev_warn(hdev->dev, "Hash failed with error %d\n", err);
304 		ctx->flags |= DRIVER_FLAGS_ERROR;
305 	}
306 
307 	hdev->flags &= ~(DRIVER_FLAGS_DMA_READY | DRIVER_FLAGS_OUTPUT_READY |
308 		DRIVER_FLAGS_CPU | DRIVER_FLAGS_BUSY | DRIVER_FLAGS_FINAL);
309 
310 	if (req->base.complete)
311 		ahash_request_complete(req, err);
312 }
313 
314 static int img_hash_write_via_dma(struct img_hash_dev *hdev)
315 {
316 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
317 
318 	img_hash_start(hdev, true);
319 
320 	dev_dbg(hdev->dev, "xmit dma size: %d\n", ctx->total);
321 
322 	if (!ctx->total)
323 		hdev->flags |= DRIVER_FLAGS_FINAL;
324 
325 	hdev->flags |= DRIVER_FLAGS_DMA_ACTIVE | DRIVER_FLAGS_FINAL;
326 
327 	tasklet_schedule(&hdev->dma_task);
328 
329 	return -EINPROGRESS;
330 }
331 
332 static int img_hash_dma_init(struct img_hash_dev *hdev)
333 {
334 	struct dma_slave_config dma_conf;
335 	int err;
336 
337 	hdev->dma_lch = dma_request_chan(hdev->dev, "tx");
338 	if (IS_ERR(hdev->dma_lch)) {
339 		dev_err(hdev->dev, "Couldn't acquire a slave DMA channel.\n");
340 		return PTR_ERR(hdev->dma_lch);
341 	}
342 	dma_conf.direction = DMA_MEM_TO_DEV;
343 	dma_conf.dst_addr = hdev->bus_addr;
344 	dma_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
345 	dma_conf.dst_maxburst = IMG_HASH_DMA_BURST;
346 	dma_conf.device_fc = false;
347 
348 	err = dmaengine_slave_config(hdev->dma_lch,  &dma_conf);
349 	if (err) {
350 		dev_err(hdev->dev, "Couldn't configure DMA slave.\n");
351 		dma_release_channel(hdev->dma_lch);
352 		return err;
353 	}
354 
355 	return 0;
356 }
357 
358 static void img_hash_dma_task(unsigned long d)
359 {
360 	struct img_hash_dev *hdev = (struct img_hash_dev *)d;
361 	struct img_hash_request_ctx *ctx;
362 	u8 *addr;
363 	size_t nbytes, bleft, wsend, len, tbc;
364 	struct scatterlist tsg;
365 
366 	if (!hdev->req)
367 		return;
368 
369 	ctx = ahash_request_ctx(hdev->req);
370 	if (!ctx->sg)
371 		return;
372 
373 	addr = sg_virt(ctx->sg);
374 	nbytes = ctx->sg->length - ctx->offset;
375 
376 	/*
377 	 * The hash accelerator does not support a data valid mask. This means
378 	 * that if each dma (i.e. per page) is not a multiple of 4 bytes, the
379 	 * padding bytes in the last word written by that dma would erroneously
380 	 * be included in the hash. To avoid this we round down the transfer,
381 	 * and add the excess to the start of the next dma. It does not matter
382 	 * that the final dma may not be a multiple of 4 bytes as the hashing
383 	 * block is programmed to accept the correct number of bytes.
384 	 */
385 
386 	bleft = nbytes % 4;
387 	wsend = (nbytes / 4);
388 
389 	if (wsend) {
390 		sg_init_one(&tsg, addr + ctx->offset, wsend * 4);
391 		if (img_hash_xmit_dma(hdev, &tsg)) {
392 			dev_err(hdev->dev, "DMA failed, falling back to CPU");
393 			ctx->flags |= DRIVER_FLAGS_CPU;
394 			hdev->err = 0;
395 			img_hash_xmit_cpu(hdev, addr + ctx->offset,
396 					  wsend * 4, 0);
397 			ctx->sent += wsend * 4;
398 			wsend = 0;
399 		} else {
400 			ctx->sent += wsend * 4;
401 		}
402 	}
403 
404 	if (bleft) {
405 		ctx->bufcnt = sg_pcopy_to_buffer(ctx->sgfirst, ctx->nents,
406 						 ctx->buffer, bleft, ctx->sent);
407 		tbc = 0;
408 		ctx->sg = sg_next(ctx->sg);
409 		while (ctx->sg && (ctx->bufcnt < 4)) {
410 			len = ctx->sg->length;
411 			if (likely(len > (4 - ctx->bufcnt)))
412 				len = 4 - ctx->bufcnt;
413 			tbc = sg_pcopy_to_buffer(ctx->sgfirst, ctx->nents,
414 						 ctx->buffer + ctx->bufcnt, len,
415 					ctx->sent + ctx->bufcnt);
416 			ctx->bufcnt += tbc;
417 			if (tbc >= ctx->sg->length) {
418 				ctx->sg = sg_next(ctx->sg);
419 				tbc = 0;
420 			}
421 		}
422 
423 		ctx->sent += ctx->bufcnt;
424 		ctx->offset = tbc;
425 
426 		if (!wsend)
427 			img_hash_dma_callback(hdev);
428 	} else {
429 		ctx->offset = 0;
430 		ctx->sg = sg_next(ctx->sg);
431 	}
432 }
433 
434 static int img_hash_write_via_dma_stop(struct img_hash_dev *hdev)
435 {
436 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
437 
438 	if (ctx->flags & DRIVER_FLAGS_SG)
439 		dma_unmap_sg(hdev->dev, ctx->sg, ctx->dma_ct, DMA_TO_DEVICE);
440 
441 	return 0;
442 }
443 
444 static int img_hash_process_data(struct img_hash_dev *hdev)
445 {
446 	struct ahash_request *req = hdev->req;
447 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
448 	int err = 0;
449 
450 	ctx->bufcnt = 0;
451 
452 	if (req->nbytes >= IMG_HASH_DMA_THRESHOLD) {
453 		dev_dbg(hdev->dev, "process data request(%d bytes) using DMA\n",
454 			req->nbytes);
455 		err = img_hash_write_via_dma(hdev);
456 	} else {
457 		dev_dbg(hdev->dev, "process data request(%d bytes) using CPU\n",
458 			req->nbytes);
459 		err = img_hash_write_via_cpu(hdev);
460 	}
461 	return err;
462 }
463 
464 static int img_hash_hw_init(struct img_hash_dev *hdev)
465 {
466 	unsigned long long nbits;
467 	u32 u, l;
468 
469 	img_hash_write(hdev, CR_RESET, CR_RESET_SET);
470 	img_hash_write(hdev, CR_RESET, CR_RESET_UNSET);
471 	img_hash_write(hdev, CR_INTENAB, CR_INT_NEW_RESULTS_SET);
472 
473 	nbits = (u64)hdev->req->nbytes << 3;
474 	u = nbits >> 32;
475 	l = nbits;
476 	img_hash_write(hdev, CR_MESSAGE_LENGTH_H, u);
477 	img_hash_write(hdev, CR_MESSAGE_LENGTH_L, l);
478 
479 	if (!(DRIVER_FLAGS_INIT & hdev->flags)) {
480 		hdev->flags |= DRIVER_FLAGS_INIT;
481 		hdev->err = 0;
482 	}
483 	dev_dbg(hdev->dev, "hw initialized, nbits: %llx\n", nbits);
484 	return 0;
485 }
486 
487 static int img_hash_init(struct ahash_request *req)
488 {
489 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
490 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
491 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
492 
493 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
494 	rctx->fallback_req.base.flags =	req->base.flags
495 		& CRYPTO_TFM_REQ_MAY_SLEEP;
496 
497 	return crypto_ahash_init(&rctx->fallback_req);
498 }
499 
500 static int img_hash_handle_queue(struct img_hash_dev *hdev,
501 				 struct ahash_request *req)
502 {
503 	struct crypto_async_request *async_req, *backlog;
504 	struct img_hash_request_ctx *ctx;
505 	unsigned long flags;
506 	int err = 0, res = 0;
507 
508 	spin_lock_irqsave(&hdev->lock, flags);
509 
510 	if (req)
511 		res = ahash_enqueue_request(&hdev->queue, req);
512 
513 	if (DRIVER_FLAGS_BUSY & hdev->flags) {
514 		spin_unlock_irqrestore(&hdev->lock, flags);
515 		return res;
516 	}
517 
518 	backlog = crypto_get_backlog(&hdev->queue);
519 	async_req = crypto_dequeue_request(&hdev->queue);
520 	if (async_req)
521 		hdev->flags |= DRIVER_FLAGS_BUSY;
522 
523 	spin_unlock_irqrestore(&hdev->lock, flags);
524 
525 	if (!async_req)
526 		return res;
527 
528 	if (backlog)
529 		crypto_request_complete(backlog, -EINPROGRESS);
530 
531 	req = ahash_request_cast(async_req);
532 	hdev->req = req;
533 
534 	ctx = ahash_request_ctx(req);
535 
536 	dev_info(hdev->dev, "processing req, op: %lu, bytes: %d\n",
537 		 ctx->op, req->nbytes);
538 
539 	err = img_hash_hw_init(hdev);
540 
541 	if (!err)
542 		err = img_hash_process_data(hdev);
543 
544 	if (err != -EINPROGRESS) {
545 		/* done_task will not finish so do it here */
546 		img_hash_finish_req(req, err);
547 	}
548 	return res;
549 }
550 
551 static int img_hash_update(struct ahash_request *req)
552 {
553 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
554 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
555 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
556 
557 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
558 	rctx->fallback_req.base.flags = req->base.flags
559 		& CRYPTO_TFM_REQ_MAY_SLEEP;
560 	rctx->fallback_req.nbytes = req->nbytes;
561 	rctx->fallback_req.src = req->src;
562 
563 	return crypto_ahash_update(&rctx->fallback_req);
564 }
565 
566 static int img_hash_final(struct ahash_request *req)
567 {
568 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
569 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
570 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
571 
572 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
573 	rctx->fallback_req.base.flags = req->base.flags
574 		& CRYPTO_TFM_REQ_MAY_SLEEP;
575 	rctx->fallback_req.result = req->result;
576 
577 	return crypto_ahash_final(&rctx->fallback_req);
578 }
579 
580 static int img_hash_finup(struct ahash_request *req)
581 {
582 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
583 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
584 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
585 
586 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
587 	rctx->fallback_req.base.flags = req->base.flags
588 		& CRYPTO_TFM_REQ_MAY_SLEEP;
589 	rctx->fallback_req.nbytes = req->nbytes;
590 	rctx->fallback_req.src = req->src;
591 	rctx->fallback_req.result = req->result;
592 
593 	return crypto_ahash_finup(&rctx->fallback_req);
594 }
595 
596 static int img_hash_import(struct ahash_request *req, const void *in)
597 {
598 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
599 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
600 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
601 
602 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
603 	rctx->fallback_req.base.flags = req->base.flags
604 		& CRYPTO_TFM_REQ_MAY_SLEEP;
605 
606 	return crypto_ahash_import(&rctx->fallback_req, in);
607 }
608 
609 static int img_hash_export(struct ahash_request *req, void *out)
610 {
611 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
612 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
613 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
614 
615 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
616 	rctx->fallback_req.base.flags = req->base.flags
617 		& CRYPTO_TFM_REQ_MAY_SLEEP;
618 
619 	return crypto_ahash_export(&rctx->fallback_req, out);
620 }
621 
622 static int img_hash_digest(struct ahash_request *req)
623 {
624 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
625 	struct img_hash_ctx *tctx = crypto_ahash_ctx(tfm);
626 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
627 	struct img_hash_dev *hdev = NULL;
628 	struct img_hash_dev *tmp;
629 	int err;
630 
631 	spin_lock(&img_hash.lock);
632 	if (!tctx->hdev) {
633 		list_for_each_entry(tmp, &img_hash.dev_list, list) {
634 			hdev = tmp;
635 			break;
636 		}
637 		tctx->hdev = hdev;
638 
639 	} else {
640 		hdev = tctx->hdev;
641 	}
642 
643 	spin_unlock(&img_hash.lock);
644 	ctx->hdev = hdev;
645 	ctx->flags = 0;
646 	ctx->digsize = crypto_ahash_digestsize(tfm);
647 
648 	switch (ctx->digsize) {
649 	case SHA1_DIGEST_SIZE:
650 		ctx->flags |= DRIVER_FLAGS_SHA1;
651 		break;
652 	case SHA256_DIGEST_SIZE:
653 		ctx->flags |= DRIVER_FLAGS_SHA256;
654 		break;
655 	case SHA224_DIGEST_SIZE:
656 		ctx->flags |= DRIVER_FLAGS_SHA224;
657 		break;
658 	case MD5_DIGEST_SIZE:
659 		ctx->flags |= DRIVER_FLAGS_MD5;
660 		break;
661 	default:
662 		return -EINVAL;
663 	}
664 
665 	ctx->bufcnt = 0;
666 	ctx->offset = 0;
667 	ctx->sent = 0;
668 	ctx->total = req->nbytes;
669 	ctx->sg = req->src;
670 	ctx->sgfirst = req->src;
671 	ctx->nents = sg_nents(ctx->sg);
672 
673 	err = img_hash_handle_queue(tctx->hdev, req);
674 
675 	return err;
676 }
677 
678 static int img_hash_cra_init(struct crypto_tfm *tfm, const char *alg_name)
679 {
680 	struct img_hash_ctx *ctx = crypto_tfm_ctx(tfm);
681 
682 	ctx->fallback = crypto_alloc_ahash(alg_name, 0,
683 					   CRYPTO_ALG_NEED_FALLBACK);
684 	if (IS_ERR(ctx->fallback)) {
685 		pr_err("img_hash: Could not load fallback driver.\n");
686 		return PTR_ERR(ctx->fallback);
687 	}
688 	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
689 				 sizeof(struct img_hash_request_ctx) +
690 				 crypto_ahash_reqsize(ctx->fallback) +
691 				 IMG_HASH_DMA_THRESHOLD);
692 
693 	return 0;
694 }
695 
696 static int img_hash_cra_md5_init(struct crypto_tfm *tfm)
697 {
698 	return img_hash_cra_init(tfm, "md5-generic");
699 }
700 
701 static int img_hash_cra_sha1_init(struct crypto_tfm *tfm)
702 {
703 	return img_hash_cra_init(tfm, "sha1-generic");
704 }
705 
706 static int img_hash_cra_sha224_init(struct crypto_tfm *tfm)
707 {
708 	return img_hash_cra_init(tfm, "sha224-generic");
709 }
710 
711 static int img_hash_cra_sha256_init(struct crypto_tfm *tfm)
712 {
713 	return img_hash_cra_init(tfm, "sha256-generic");
714 }
715 
716 static void img_hash_cra_exit(struct crypto_tfm *tfm)
717 {
718 	struct img_hash_ctx *tctx = crypto_tfm_ctx(tfm);
719 
720 	crypto_free_ahash(tctx->fallback);
721 }
722 
723 static irqreturn_t img_irq_handler(int irq, void *dev_id)
724 {
725 	struct img_hash_dev *hdev = dev_id;
726 	u32 reg;
727 
728 	reg = img_hash_read(hdev, CR_INTSTAT);
729 	img_hash_write(hdev, CR_INTCLEAR, reg);
730 
731 	if (reg & CR_INT_NEW_RESULTS_SET) {
732 		dev_dbg(hdev->dev, "IRQ CR_INT_NEW_RESULTS_SET\n");
733 		if (DRIVER_FLAGS_BUSY & hdev->flags) {
734 			hdev->flags |= DRIVER_FLAGS_OUTPUT_READY;
735 			if (!(DRIVER_FLAGS_CPU & hdev->flags))
736 				hdev->flags |= DRIVER_FLAGS_DMA_READY;
737 			tasklet_schedule(&hdev->done_task);
738 		} else {
739 			dev_warn(hdev->dev,
740 				 "HASH interrupt when no active requests.\n");
741 		}
742 	} else if (reg & CR_INT_RESULTS_AVAILABLE) {
743 		dev_warn(hdev->dev,
744 			 "IRQ triggered before the hash had completed\n");
745 	} else if (reg & CR_INT_RESULT_READ_ERR) {
746 		dev_warn(hdev->dev,
747 			 "Attempt to read from an empty result queue\n");
748 	} else if (reg & CR_INT_MESSAGE_WRITE_ERROR) {
749 		dev_warn(hdev->dev,
750 			 "Data written before the hardware was configured\n");
751 	}
752 	return IRQ_HANDLED;
753 }
754 
755 static struct ahash_alg img_algs[] = {
756 	{
757 		.init = img_hash_init,
758 		.update = img_hash_update,
759 		.final = img_hash_final,
760 		.finup = img_hash_finup,
761 		.export = img_hash_export,
762 		.import = img_hash_import,
763 		.digest = img_hash_digest,
764 		.halg = {
765 			.digestsize = MD5_DIGEST_SIZE,
766 			.statesize = sizeof(struct md5_state),
767 			.base = {
768 				.cra_name = "md5",
769 				.cra_driver_name = "img-md5",
770 				.cra_priority = 300,
771 				.cra_flags =
772 				CRYPTO_ALG_ASYNC |
773 				CRYPTO_ALG_NEED_FALLBACK,
774 				.cra_blocksize = MD5_HMAC_BLOCK_SIZE,
775 				.cra_ctxsize = sizeof(struct img_hash_ctx),
776 				.cra_init = img_hash_cra_md5_init,
777 				.cra_exit = img_hash_cra_exit,
778 				.cra_module = THIS_MODULE,
779 			}
780 		}
781 	},
782 	{
783 		.init = img_hash_init,
784 		.update = img_hash_update,
785 		.final = img_hash_final,
786 		.finup = img_hash_finup,
787 		.export = img_hash_export,
788 		.import = img_hash_import,
789 		.digest = img_hash_digest,
790 		.halg = {
791 			.digestsize = SHA1_DIGEST_SIZE,
792 			.statesize = sizeof(struct sha1_state),
793 			.base = {
794 				.cra_name = "sha1",
795 				.cra_driver_name = "img-sha1",
796 				.cra_priority = 300,
797 				.cra_flags =
798 				CRYPTO_ALG_ASYNC |
799 				CRYPTO_ALG_NEED_FALLBACK,
800 				.cra_blocksize = SHA1_BLOCK_SIZE,
801 				.cra_ctxsize = sizeof(struct img_hash_ctx),
802 				.cra_init = img_hash_cra_sha1_init,
803 				.cra_exit = img_hash_cra_exit,
804 				.cra_module = THIS_MODULE,
805 			}
806 		}
807 	},
808 	{
809 		.init = img_hash_init,
810 		.update = img_hash_update,
811 		.final = img_hash_final,
812 		.finup = img_hash_finup,
813 		.export = img_hash_export,
814 		.import = img_hash_import,
815 		.digest = img_hash_digest,
816 		.halg = {
817 			.digestsize = SHA224_DIGEST_SIZE,
818 			.statesize = sizeof(struct sha256_state),
819 			.base = {
820 				.cra_name = "sha224",
821 				.cra_driver_name = "img-sha224",
822 				.cra_priority = 300,
823 				.cra_flags =
824 				CRYPTO_ALG_ASYNC |
825 				CRYPTO_ALG_NEED_FALLBACK,
826 				.cra_blocksize = SHA224_BLOCK_SIZE,
827 				.cra_ctxsize = sizeof(struct img_hash_ctx),
828 				.cra_init = img_hash_cra_sha224_init,
829 				.cra_exit = img_hash_cra_exit,
830 				.cra_module = THIS_MODULE,
831 			}
832 		}
833 	},
834 	{
835 		.init = img_hash_init,
836 		.update = img_hash_update,
837 		.final = img_hash_final,
838 		.finup = img_hash_finup,
839 		.export = img_hash_export,
840 		.import = img_hash_import,
841 		.digest = img_hash_digest,
842 		.halg = {
843 			.digestsize = SHA256_DIGEST_SIZE,
844 			.statesize = sizeof(struct sha256_state),
845 			.base = {
846 				.cra_name = "sha256",
847 				.cra_driver_name = "img-sha256",
848 				.cra_priority = 300,
849 				.cra_flags =
850 				CRYPTO_ALG_ASYNC |
851 				CRYPTO_ALG_NEED_FALLBACK,
852 				.cra_blocksize = SHA256_BLOCK_SIZE,
853 				.cra_ctxsize = sizeof(struct img_hash_ctx),
854 				.cra_init = img_hash_cra_sha256_init,
855 				.cra_exit = img_hash_cra_exit,
856 				.cra_module = THIS_MODULE,
857 			}
858 		}
859 	}
860 };
861 
862 static int img_register_algs(struct img_hash_dev *hdev)
863 {
864 	int i, err;
865 
866 	for (i = 0; i < ARRAY_SIZE(img_algs); i++) {
867 		err = crypto_register_ahash(&img_algs[i]);
868 		if (err)
869 			goto err_reg;
870 	}
871 	return 0;
872 
873 err_reg:
874 	for (; i--; )
875 		crypto_unregister_ahash(&img_algs[i]);
876 
877 	return err;
878 }
879 
880 static int img_unregister_algs(struct img_hash_dev *hdev)
881 {
882 	int i;
883 
884 	for (i = 0; i < ARRAY_SIZE(img_algs); i++)
885 		crypto_unregister_ahash(&img_algs[i]);
886 	return 0;
887 }
888 
889 static void img_hash_done_task(unsigned long data)
890 {
891 	struct img_hash_dev *hdev = (struct img_hash_dev *)data;
892 	int err = 0;
893 
894 	if (hdev->err == -EINVAL) {
895 		err = hdev->err;
896 		goto finish;
897 	}
898 
899 	if (!(DRIVER_FLAGS_BUSY & hdev->flags)) {
900 		img_hash_handle_queue(hdev, NULL);
901 		return;
902 	}
903 
904 	if (DRIVER_FLAGS_CPU & hdev->flags) {
905 		if (DRIVER_FLAGS_OUTPUT_READY & hdev->flags) {
906 			hdev->flags &= ~DRIVER_FLAGS_OUTPUT_READY;
907 			goto finish;
908 		}
909 	} else if (DRIVER_FLAGS_DMA_READY & hdev->flags) {
910 		if (DRIVER_FLAGS_DMA_ACTIVE & hdev->flags) {
911 			hdev->flags &= ~DRIVER_FLAGS_DMA_ACTIVE;
912 			img_hash_write_via_dma_stop(hdev);
913 			if (hdev->err) {
914 				err = hdev->err;
915 				goto finish;
916 			}
917 		}
918 		if (DRIVER_FLAGS_OUTPUT_READY & hdev->flags) {
919 			hdev->flags &= ~(DRIVER_FLAGS_DMA_READY |
920 					DRIVER_FLAGS_OUTPUT_READY);
921 			goto finish;
922 		}
923 	}
924 	return;
925 
926 finish:
927 	img_hash_finish_req(hdev->req, err);
928 }
929 
930 static const struct of_device_id img_hash_match[] = {
931 	{ .compatible = "img,hash-accelerator" },
932 	{}
933 };
934 MODULE_DEVICE_TABLE(of, img_hash_match);
935 
936 static int img_hash_probe(struct platform_device *pdev)
937 {
938 	struct img_hash_dev *hdev;
939 	struct device *dev = &pdev->dev;
940 	struct resource *hash_res;
941 	int	irq;
942 	int err;
943 
944 	hdev = devm_kzalloc(dev, sizeof(*hdev), GFP_KERNEL);
945 	if (hdev == NULL)
946 		return -ENOMEM;
947 
948 	spin_lock_init(&hdev->lock);
949 
950 	hdev->dev = dev;
951 
952 	platform_set_drvdata(pdev, hdev);
953 
954 	INIT_LIST_HEAD(&hdev->list);
955 
956 	tasklet_init(&hdev->done_task, img_hash_done_task, (unsigned long)hdev);
957 	tasklet_init(&hdev->dma_task, img_hash_dma_task, (unsigned long)hdev);
958 
959 	crypto_init_queue(&hdev->queue, IMG_HASH_QUEUE_LENGTH);
960 
961 	/* Register bank */
962 	hdev->io_base = devm_platform_ioremap_resource(pdev, 0);
963 	if (IS_ERR(hdev->io_base)) {
964 		err = PTR_ERR(hdev->io_base);
965 		goto res_err;
966 	}
967 
968 	/* Write port (DMA or CPU) */
969 	hash_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
970 	hdev->cpu_addr = devm_ioremap_resource(dev, hash_res);
971 	if (IS_ERR(hdev->cpu_addr)) {
972 		err = PTR_ERR(hdev->cpu_addr);
973 		goto res_err;
974 	}
975 	hdev->bus_addr = hash_res->start;
976 
977 	irq = platform_get_irq(pdev, 0);
978 	if (irq < 0) {
979 		err = irq;
980 		goto res_err;
981 	}
982 
983 	err = devm_request_irq(dev, irq, img_irq_handler, 0,
984 			       dev_name(dev), hdev);
985 	if (err) {
986 		dev_err(dev, "unable to request irq\n");
987 		goto res_err;
988 	}
989 	dev_dbg(dev, "using IRQ channel %d\n", irq);
990 
991 	hdev->hash_clk = devm_clk_get(&pdev->dev, "hash");
992 	if (IS_ERR(hdev->hash_clk)) {
993 		dev_err(dev, "clock initialization failed.\n");
994 		err = PTR_ERR(hdev->hash_clk);
995 		goto res_err;
996 	}
997 
998 	hdev->sys_clk = devm_clk_get(&pdev->dev, "sys");
999 	if (IS_ERR(hdev->sys_clk)) {
1000 		dev_err(dev, "clock initialization failed.\n");
1001 		err = PTR_ERR(hdev->sys_clk);
1002 		goto res_err;
1003 	}
1004 
1005 	err = clk_prepare_enable(hdev->hash_clk);
1006 	if (err)
1007 		goto res_err;
1008 
1009 	err = clk_prepare_enable(hdev->sys_clk);
1010 	if (err)
1011 		goto clk_err;
1012 
1013 	err = img_hash_dma_init(hdev);
1014 	if (err)
1015 		goto dma_err;
1016 
1017 	dev_dbg(dev, "using %s for DMA transfers\n",
1018 		dma_chan_name(hdev->dma_lch));
1019 
1020 	spin_lock(&img_hash.lock);
1021 	list_add_tail(&hdev->list, &img_hash.dev_list);
1022 	spin_unlock(&img_hash.lock);
1023 
1024 	err = img_register_algs(hdev);
1025 	if (err)
1026 		goto err_algs;
1027 	dev_info(dev, "Img MD5/SHA1/SHA224/SHA256 Hardware accelerator initialized\n");
1028 
1029 	return 0;
1030 
1031 err_algs:
1032 	spin_lock(&img_hash.lock);
1033 	list_del(&hdev->list);
1034 	spin_unlock(&img_hash.lock);
1035 	dma_release_channel(hdev->dma_lch);
1036 dma_err:
1037 	clk_disable_unprepare(hdev->sys_clk);
1038 clk_err:
1039 	clk_disable_unprepare(hdev->hash_clk);
1040 res_err:
1041 	tasklet_kill(&hdev->done_task);
1042 	tasklet_kill(&hdev->dma_task);
1043 
1044 	return err;
1045 }
1046 
1047 static int img_hash_remove(struct platform_device *pdev)
1048 {
1049 	struct img_hash_dev *hdev;
1050 
1051 	hdev = platform_get_drvdata(pdev);
1052 	spin_lock(&img_hash.lock);
1053 	list_del(&hdev->list);
1054 	spin_unlock(&img_hash.lock);
1055 
1056 	img_unregister_algs(hdev);
1057 
1058 	tasklet_kill(&hdev->done_task);
1059 	tasklet_kill(&hdev->dma_task);
1060 
1061 	dma_release_channel(hdev->dma_lch);
1062 
1063 	clk_disable_unprepare(hdev->hash_clk);
1064 	clk_disable_unprepare(hdev->sys_clk);
1065 
1066 	return 0;
1067 }
1068 
1069 #ifdef CONFIG_PM_SLEEP
1070 static int img_hash_suspend(struct device *dev)
1071 {
1072 	struct img_hash_dev *hdev = dev_get_drvdata(dev);
1073 
1074 	clk_disable_unprepare(hdev->hash_clk);
1075 	clk_disable_unprepare(hdev->sys_clk);
1076 
1077 	return 0;
1078 }
1079 
1080 static int img_hash_resume(struct device *dev)
1081 {
1082 	struct img_hash_dev *hdev = dev_get_drvdata(dev);
1083 	int ret;
1084 
1085 	ret = clk_prepare_enable(hdev->hash_clk);
1086 	if (ret)
1087 		return ret;
1088 
1089 	ret = clk_prepare_enable(hdev->sys_clk);
1090 	if (ret) {
1091 		clk_disable_unprepare(hdev->hash_clk);
1092 		return ret;
1093 	}
1094 
1095 	return 0;
1096 }
1097 #endif /* CONFIG_PM_SLEEP */
1098 
1099 static const struct dev_pm_ops img_hash_pm_ops = {
1100 	SET_SYSTEM_SLEEP_PM_OPS(img_hash_suspend, img_hash_resume)
1101 };
1102 
1103 static struct platform_driver img_hash_driver = {
1104 	.probe		= img_hash_probe,
1105 	.remove		= img_hash_remove,
1106 	.driver		= {
1107 		.name	= "img-hash-accelerator",
1108 		.pm	= &img_hash_pm_ops,
1109 		.of_match_table	= of_match_ptr(img_hash_match),
1110 	}
1111 };
1112 module_platform_driver(img_hash_driver);
1113 
1114 MODULE_LICENSE("GPL v2");
1115 MODULE_DESCRIPTION("Imgtec SHA1/224/256 & MD5 hw accelerator driver");
1116 MODULE_AUTHOR("Will Thomas.");
1117 MODULE_AUTHOR("James Hartley <james.hartley@imgtec.com>");
1118