xref: /openbmc/linux/drivers/crypto/img-hash.c (revision 6d99a79c)
1 /*
2  * Copyright (c) 2014 Imagination Technologies
3  * Authors:  Will Thomas, James Hartley
4  *
5  * This program is free software; you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as published
7  * by the Free Software Foundation.
8  *
9  *	Interface structure taken from omap-sham driver
10  */
11 
12 #include <linux/clk.h>
13 #include <linux/dmaengine.h>
14 #include <linux/interrupt.h>
15 #include <linux/io.h>
16 #include <linux/kernel.h>
17 #include <linux/module.h>
18 #include <linux/of_device.h>
19 #include <linux/platform_device.h>
20 #include <linux/scatterlist.h>
21 
22 #include <crypto/internal/hash.h>
23 #include <crypto/md5.h>
24 #include <crypto/sha.h>
25 
26 #define CR_RESET			0
27 #define CR_RESET_SET			1
28 #define CR_RESET_UNSET			0
29 
30 #define CR_MESSAGE_LENGTH_H		0x4
31 #define CR_MESSAGE_LENGTH_L		0x8
32 
33 #define CR_CONTROL			0xc
34 #define CR_CONTROL_BYTE_ORDER_3210	0
35 #define CR_CONTROL_BYTE_ORDER_0123	1
36 #define CR_CONTROL_BYTE_ORDER_2310	2
37 #define CR_CONTROL_BYTE_ORDER_1032	3
38 #define CR_CONTROL_BYTE_ORDER_SHIFT	8
39 #define CR_CONTROL_ALGO_MD5	0
40 #define CR_CONTROL_ALGO_SHA1	1
41 #define CR_CONTROL_ALGO_SHA224	2
42 #define CR_CONTROL_ALGO_SHA256	3
43 
44 #define CR_INTSTAT			0x10
45 #define CR_INTENAB			0x14
46 #define CR_INTCLEAR			0x18
47 #define CR_INT_RESULTS_AVAILABLE	BIT(0)
48 #define CR_INT_NEW_RESULTS_SET		BIT(1)
49 #define CR_INT_RESULT_READ_ERR		BIT(2)
50 #define CR_INT_MESSAGE_WRITE_ERROR	BIT(3)
51 #define CR_INT_STATUS			BIT(8)
52 
53 #define CR_RESULT_QUEUE		0x1c
54 #define CR_RSD0				0x40
55 #define CR_CORE_REV			0x50
56 #define CR_CORE_DES1		0x60
57 #define CR_CORE_DES2		0x70
58 
59 #define DRIVER_FLAGS_BUSY		BIT(0)
60 #define DRIVER_FLAGS_FINAL		BIT(1)
61 #define DRIVER_FLAGS_DMA_ACTIVE		BIT(2)
62 #define DRIVER_FLAGS_OUTPUT_READY	BIT(3)
63 #define DRIVER_FLAGS_INIT		BIT(4)
64 #define DRIVER_FLAGS_CPU		BIT(5)
65 #define DRIVER_FLAGS_DMA_READY		BIT(6)
66 #define DRIVER_FLAGS_ERROR		BIT(7)
67 #define DRIVER_FLAGS_SG			BIT(8)
68 #define DRIVER_FLAGS_SHA1		BIT(18)
69 #define DRIVER_FLAGS_SHA224		BIT(19)
70 #define DRIVER_FLAGS_SHA256		BIT(20)
71 #define DRIVER_FLAGS_MD5		BIT(21)
72 
73 #define IMG_HASH_QUEUE_LENGTH		20
74 #define IMG_HASH_DMA_BURST		4
75 #define IMG_HASH_DMA_THRESHOLD		64
76 
77 #ifdef __LITTLE_ENDIAN
78 #define IMG_HASH_BYTE_ORDER		CR_CONTROL_BYTE_ORDER_3210
79 #else
80 #define IMG_HASH_BYTE_ORDER		CR_CONTROL_BYTE_ORDER_0123
81 #endif
82 
83 struct img_hash_dev;
84 
85 struct img_hash_request_ctx {
86 	struct img_hash_dev	*hdev;
87 	u8 digest[SHA256_DIGEST_SIZE] __aligned(sizeof(u32));
88 	unsigned long		flags;
89 	size_t			digsize;
90 
91 	dma_addr_t		dma_addr;
92 	size_t			dma_ct;
93 
94 	/* sg root */
95 	struct scatterlist	*sgfirst;
96 	/* walk state */
97 	struct scatterlist	*sg;
98 	size_t			nents;
99 	size_t			offset;
100 	unsigned int		total;
101 	size_t			sent;
102 
103 	unsigned long		op;
104 
105 	size_t			bufcnt;
106 	struct ahash_request	fallback_req;
107 
108 	/* Zero length buffer must remain last member of struct */
109 	u8 buffer[0] __aligned(sizeof(u32));
110 };
111 
112 struct img_hash_ctx {
113 	struct img_hash_dev	*hdev;
114 	unsigned long		flags;
115 	struct crypto_ahash	*fallback;
116 };
117 
118 struct img_hash_dev {
119 	struct list_head	list;
120 	struct device		*dev;
121 	struct clk		*hash_clk;
122 	struct clk		*sys_clk;
123 	void __iomem		*io_base;
124 
125 	phys_addr_t		bus_addr;
126 	void __iomem		*cpu_addr;
127 
128 	spinlock_t		lock;
129 	int			err;
130 	struct tasklet_struct	done_task;
131 	struct tasklet_struct	dma_task;
132 
133 	unsigned long		flags;
134 	struct crypto_queue	queue;
135 	struct ahash_request	*req;
136 
137 	struct dma_chan		*dma_lch;
138 };
139 
140 struct img_hash_drv {
141 	struct list_head dev_list;
142 	spinlock_t lock;
143 };
144 
145 static struct img_hash_drv img_hash = {
146 	.dev_list = LIST_HEAD_INIT(img_hash.dev_list),
147 	.lock = __SPIN_LOCK_UNLOCKED(img_hash.lock),
148 };
149 
150 static inline u32 img_hash_read(struct img_hash_dev *hdev, u32 offset)
151 {
152 	return readl_relaxed(hdev->io_base + offset);
153 }
154 
155 static inline void img_hash_write(struct img_hash_dev *hdev,
156 				  u32 offset, u32 value)
157 {
158 	writel_relaxed(value, hdev->io_base + offset);
159 }
160 
161 static inline u32 img_hash_read_result_queue(struct img_hash_dev *hdev)
162 {
163 	return be32_to_cpu(img_hash_read(hdev, CR_RESULT_QUEUE));
164 }
165 
166 static void img_hash_start(struct img_hash_dev *hdev, bool dma)
167 {
168 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
169 	u32 cr = IMG_HASH_BYTE_ORDER << CR_CONTROL_BYTE_ORDER_SHIFT;
170 
171 	if (ctx->flags & DRIVER_FLAGS_MD5)
172 		cr |= CR_CONTROL_ALGO_MD5;
173 	else if (ctx->flags & DRIVER_FLAGS_SHA1)
174 		cr |= CR_CONTROL_ALGO_SHA1;
175 	else if (ctx->flags & DRIVER_FLAGS_SHA224)
176 		cr |= CR_CONTROL_ALGO_SHA224;
177 	else if (ctx->flags & DRIVER_FLAGS_SHA256)
178 		cr |= CR_CONTROL_ALGO_SHA256;
179 	dev_dbg(hdev->dev, "Starting hash process\n");
180 	img_hash_write(hdev, CR_CONTROL, cr);
181 
182 	/*
183 	 * The hardware block requires two cycles between writing the control
184 	 * register and writing the first word of data in non DMA mode, to
185 	 * ensure the first data write is not grouped in burst with the control
186 	 * register write a read is issued to 'flush' the bus.
187 	 */
188 	if (!dma)
189 		img_hash_read(hdev, CR_CONTROL);
190 }
191 
192 static int img_hash_xmit_cpu(struct img_hash_dev *hdev, const u8 *buf,
193 			     size_t length, int final)
194 {
195 	u32 count, len32;
196 	const u32 *buffer = (const u32 *)buf;
197 
198 	dev_dbg(hdev->dev, "xmit_cpu:  length: %zu bytes\n", length);
199 
200 	if (final)
201 		hdev->flags |= DRIVER_FLAGS_FINAL;
202 
203 	len32 = DIV_ROUND_UP(length, sizeof(u32));
204 
205 	for (count = 0; count < len32; count++)
206 		writel_relaxed(buffer[count], hdev->cpu_addr);
207 
208 	return -EINPROGRESS;
209 }
210 
211 static void img_hash_dma_callback(void *data)
212 {
213 	struct img_hash_dev *hdev = (struct img_hash_dev *)data;
214 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
215 
216 	if (ctx->bufcnt) {
217 		img_hash_xmit_cpu(hdev, ctx->buffer, ctx->bufcnt, 0);
218 		ctx->bufcnt = 0;
219 	}
220 	if (ctx->sg)
221 		tasklet_schedule(&hdev->dma_task);
222 }
223 
224 static int img_hash_xmit_dma(struct img_hash_dev *hdev, struct scatterlist *sg)
225 {
226 	struct dma_async_tx_descriptor *desc;
227 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
228 
229 	ctx->dma_ct = dma_map_sg(hdev->dev, sg, 1, DMA_TO_DEVICE);
230 	if (ctx->dma_ct == 0) {
231 		dev_err(hdev->dev, "Invalid DMA sg\n");
232 		hdev->err = -EINVAL;
233 		return -EINVAL;
234 	}
235 
236 	desc = dmaengine_prep_slave_sg(hdev->dma_lch,
237 				       sg,
238 				       ctx->dma_ct,
239 				       DMA_MEM_TO_DEV,
240 				       DMA_PREP_INTERRUPT | DMA_CTRL_ACK);
241 	if (!desc) {
242 		dev_err(hdev->dev, "Null DMA descriptor\n");
243 		hdev->err = -EINVAL;
244 		dma_unmap_sg(hdev->dev, sg, 1, DMA_TO_DEVICE);
245 		return -EINVAL;
246 	}
247 	desc->callback = img_hash_dma_callback;
248 	desc->callback_param = hdev;
249 	dmaengine_submit(desc);
250 	dma_async_issue_pending(hdev->dma_lch);
251 
252 	return 0;
253 }
254 
255 static int img_hash_write_via_cpu(struct img_hash_dev *hdev)
256 {
257 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
258 
259 	ctx->bufcnt = sg_copy_to_buffer(hdev->req->src, sg_nents(ctx->sg),
260 					ctx->buffer, hdev->req->nbytes);
261 
262 	ctx->total = hdev->req->nbytes;
263 	ctx->bufcnt = 0;
264 
265 	hdev->flags |= (DRIVER_FLAGS_CPU | DRIVER_FLAGS_FINAL);
266 
267 	img_hash_start(hdev, false);
268 
269 	return img_hash_xmit_cpu(hdev, ctx->buffer, ctx->total, 1);
270 }
271 
272 static int img_hash_finish(struct ahash_request *req)
273 {
274 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
275 
276 	if (!req->result)
277 		return -EINVAL;
278 
279 	memcpy(req->result, ctx->digest, ctx->digsize);
280 
281 	return 0;
282 }
283 
284 static void img_hash_copy_hash(struct ahash_request *req)
285 {
286 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
287 	u32 *hash = (u32 *)ctx->digest;
288 	int i;
289 
290 	for (i = (ctx->digsize / sizeof(u32)) - 1; i >= 0; i--)
291 		hash[i] = img_hash_read_result_queue(ctx->hdev);
292 }
293 
294 static void img_hash_finish_req(struct ahash_request *req, int err)
295 {
296 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
297 	struct img_hash_dev *hdev =  ctx->hdev;
298 
299 	if (!err) {
300 		img_hash_copy_hash(req);
301 		if (DRIVER_FLAGS_FINAL & hdev->flags)
302 			err = img_hash_finish(req);
303 	} else {
304 		dev_warn(hdev->dev, "Hash failed with error %d\n", err);
305 		ctx->flags |= DRIVER_FLAGS_ERROR;
306 	}
307 
308 	hdev->flags &= ~(DRIVER_FLAGS_DMA_READY | DRIVER_FLAGS_OUTPUT_READY |
309 		DRIVER_FLAGS_CPU | DRIVER_FLAGS_BUSY | DRIVER_FLAGS_FINAL);
310 
311 	if (req->base.complete)
312 		req->base.complete(&req->base, err);
313 }
314 
315 static int img_hash_write_via_dma(struct img_hash_dev *hdev)
316 {
317 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
318 
319 	img_hash_start(hdev, true);
320 
321 	dev_dbg(hdev->dev, "xmit dma size: %d\n", ctx->total);
322 
323 	if (!ctx->total)
324 		hdev->flags |= DRIVER_FLAGS_FINAL;
325 
326 	hdev->flags |= DRIVER_FLAGS_DMA_ACTIVE | DRIVER_FLAGS_FINAL;
327 
328 	tasklet_schedule(&hdev->dma_task);
329 
330 	return -EINPROGRESS;
331 }
332 
333 static int img_hash_dma_init(struct img_hash_dev *hdev)
334 {
335 	struct dma_slave_config dma_conf;
336 	int err = -EINVAL;
337 
338 	hdev->dma_lch = dma_request_slave_channel(hdev->dev, "tx");
339 	if (!hdev->dma_lch) {
340 		dev_err(hdev->dev, "Couldn't acquire a slave DMA channel.\n");
341 		return -EBUSY;
342 	}
343 	dma_conf.direction = DMA_MEM_TO_DEV;
344 	dma_conf.dst_addr = hdev->bus_addr;
345 	dma_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_4_BYTES;
346 	dma_conf.dst_maxburst = IMG_HASH_DMA_BURST;
347 	dma_conf.device_fc = false;
348 
349 	err = dmaengine_slave_config(hdev->dma_lch,  &dma_conf);
350 	if (err) {
351 		dev_err(hdev->dev, "Couldn't configure DMA slave.\n");
352 		dma_release_channel(hdev->dma_lch);
353 		return err;
354 	}
355 
356 	return 0;
357 }
358 
359 static void img_hash_dma_task(unsigned long d)
360 {
361 	struct img_hash_dev *hdev = (struct img_hash_dev *)d;
362 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
363 	u8 *addr;
364 	size_t nbytes, bleft, wsend, len, tbc;
365 	struct scatterlist tsg;
366 
367 	if (!hdev->req || !ctx->sg)
368 		return;
369 
370 	addr = sg_virt(ctx->sg);
371 	nbytes = ctx->sg->length - ctx->offset;
372 
373 	/*
374 	 * The hash accelerator does not support a data valid mask. This means
375 	 * that if each dma (i.e. per page) is not a multiple of 4 bytes, the
376 	 * padding bytes in the last word written by that dma would erroneously
377 	 * be included in the hash. To avoid this we round down the transfer,
378 	 * and add the excess to the start of the next dma. It does not matter
379 	 * that the final dma may not be a multiple of 4 bytes as the hashing
380 	 * block is programmed to accept the correct number of bytes.
381 	 */
382 
383 	bleft = nbytes % 4;
384 	wsend = (nbytes / 4);
385 
386 	if (wsend) {
387 		sg_init_one(&tsg, addr + ctx->offset, wsend * 4);
388 		if (img_hash_xmit_dma(hdev, &tsg)) {
389 			dev_err(hdev->dev, "DMA failed, falling back to CPU");
390 			ctx->flags |= DRIVER_FLAGS_CPU;
391 			hdev->err = 0;
392 			img_hash_xmit_cpu(hdev, addr + ctx->offset,
393 					  wsend * 4, 0);
394 			ctx->sent += wsend * 4;
395 			wsend = 0;
396 		} else {
397 			ctx->sent += wsend * 4;
398 		}
399 	}
400 
401 	if (bleft) {
402 		ctx->bufcnt = sg_pcopy_to_buffer(ctx->sgfirst, ctx->nents,
403 						 ctx->buffer, bleft, ctx->sent);
404 		tbc = 0;
405 		ctx->sg = sg_next(ctx->sg);
406 		while (ctx->sg && (ctx->bufcnt < 4)) {
407 			len = ctx->sg->length;
408 			if (likely(len > (4 - ctx->bufcnt)))
409 				len = 4 - ctx->bufcnt;
410 			tbc = sg_pcopy_to_buffer(ctx->sgfirst, ctx->nents,
411 						 ctx->buffer + ctx->bufcnt, len,
412 					ctx->sent + ctx->bufcnt);
413 			ctx->bufcnt += tbc;
414 			if (tbc >= ctx->sg->length) {
415 				ctx->sg = sg_next(ctx->sg);
416 				tbc = 0;
417 			}
418 		}
419 
420 		ctx->sent += ctx->bufcnt;
421 		ctx->offset = tbc;
422 
423 		if (!wsend)
424 			img_hash_dma_callback(hdev);
425 	} else {
426 		ctx->offset = 0;
427 		ctx->sg = sg_next(ctx->sg);
428 	}
429 }
430 
431 static int img_hash_write_via_dma_stop(struct img_hash_dev *hdev)
432 {
433 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
434 
435 	if (ctx->flags & DRIVER_FLAGS_SG)
436 		dma_unmap_sg(hdev->dev, ctx->sg, ctx->dma_ct, DMA_TO_DEVICE);
437 
438 	return 0;
439 }
440 
441 static int img_hash_process_data(struct img_hash_dev *hdev)
442 {
443 	struct ahash_request *req = hdev->req;
444 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
445 	int err = 0;
446 
447 	ctx->bufcnt = 0;
448 
449 	if (req->nbytes >= IMG_HASH_DMA_THRESHOLD) {
450 		dev_dbg(hdev->dev, "process data request(%d bytes) using DMA\n",
451 			req->nbytes);
452 		err = img_hash_write_via_dma(hdev);
453 	} else {
454 		dev_dbg(hdev->dev, "process data request(%d bytes) using CPU\n",
455 			req->nbytes);
456 		err = img_hash_write_via_cpu(hdev);
457 	}
458 	return err;
459 }
460 
461 static int img_hash_hw_init(struct img_hash_dev *hdev)
462 {
463 	unsigned long long nbits;
464 	u32 u, l;
465 
466 	img_hash_write(hdev, CR_RESET, CR_RESET_SET);
467 	img_hash_write(hdev, CR_RESET, CR_RESET_UNSET);
468 	img_hash_write(hdev, CR_INTENAB, CR_INT_NEW_RESULTS_SET);
469 
470 	nbits = (u64)hdev->req->nbytes << 3;
471 	u = nbits >> 32;
472 	l = nbits;
473 	img_hash_write(hdev, CR_MESSAGE_LENGTH_H, u);
474 	img_hash_write(hdev, CR_MESSAGE_LENGTH_L, l);
475 
476 	if (!(DRIVER_FLAGS_INIT & hdev->flags)) {
477 		hdev->flags |= DRIVER_FLAGS_INIT;
478 		hdev->err = 0;
479 	}
480 	dev_dbg(hdev->dev, "hw initialized, nbits: %llx\n", nbits);
481 	return 0;
482 }
483 
484 static int img_hash_init(struct ahash_request *req)
485 {
486 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
487 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
488 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
489 
490 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
491 	rctx->fallback_req.base.flags =	req->base.flags
492 		& CRYPTO_TFM_REQ_MAY_SLEEP;
493 
494 	return crypto_ahash_init(&rctx->fallback_req);
495 }
496 
497 static int img_hash_handle_queue(struct img_hash_dev *hdev,
498 				 struct ahash_request *req)
499 {
500 	struct crypto_async_request *async_req, *backlog;
501 	struct img_hash_request_ctx *ctx;
502 	unsigned long flags;
503 	int err = 0, res = 0;
504 
505 	spin_lock_irqsave(&hdev->lock, flags);
506 
507 	if (req)
508 		res = ahash_enqueue_request(&hdev->queue, req);
509 
510 	if (DRIVER_FLAGS_BUSY & hdev->flags) {
511 		spin_unlock_irqrestore(&hdev->lock, flags);
512 		return res;
513 	}
514 
515 	backlog = crypto_get_backlog(&hdev->queue);
516 	async_req = crypto_dequeue_request(&hdev->queue);
517 	if (async_req)
518 		hdev->flags |= DRIVER_FLAGS_BUSY;
519 
520 	spin_unlock_irqrestore(&hdev->lock, flags);
521 
522 	if (!async_req)
523 		return res;
524 
525 	if (backlog)
526 		backlog->complete(backlog, -EINPROGRESS);
527 
528 	req = ahash_request_cast(async_req);
529 	hdev->req = req;
530 
531 	ctx = ahash_request_ctx(req);
532 
533 	dev_info(hdev->dev, "processing req, op: %lu, bytes: %d\n",
534 		 ctx->op, req->nbytes);
535 
536 	err = img_hash_hw_init(hdev);
537 
538 	if (!err)
539 		err = img_hash_process_data(hdev);
540 
541 	if (err != -EINPROGRESS) {
542 		/* done_task will not finish so do it here */
543 		img_hash_finish_req(req, err);
544 	}
545 	return res;
546 }
547 
548 static int img_hash_update(struct ahash_request *req)
549 {
550 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
551 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
552 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
553 
554 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
555 	rctx->fallback_req.base.flags = req->base.flags
556 		& CRYPTO_TFM_REQ_MAY_SLEEP;
557 	rctx->fallback_req.nbytes = req->nbytes;
558 	rctx->fallback_req.src = req->src;
559 
560 	return crypto_ahash_update(&rctx->fallback_req);
561 }
562 
563 static int img_hash_final(struct ahash_request *req)
564 {
565 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
566 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
567 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
568 
569 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
570 	rctx->fallback_req.base.flags = req->base.flags
571 		& CRYPTO_TFM_REQ_MAY_SLEEP;
572 	rctx->fallback_req.result = req->result;
573 
574 	return crypto_ahash_final(&rctx->fallback_req);
575 }
576 
577 static int img_hash_finup(struct ahash_request *req)
578 {
579 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
580 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
581 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
582 
583 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
584 	rctx->fallback_req.base.flags = req->base.flags
585 		& CRYPTO_TFM_REQ_MAY_SLEEP;
586 	rctx->fallback_req.nbytes = req->nbytes;
587 	rctx->fallback_req.src = req->src;
588 	rctx->fallback_req.result = req->result;
589 
590 	return crypto_ahash_finup(&rctx->fallback_req);
591 }
592 
593 static int img_hash_import(struct ahash_request *req, const void *in)
594 {
595 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
596 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
597 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
598 
599 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
600 	rctx->fallback_req.base.flags = req->base.flags
601 		& CRYPTO_TFM_REQ_MAY_SLEEP;
602 
603 	return crypto_ahash_import(&rctx->fallback_req, in);
604 }
605 
606 static int img_hash_export(struct ahash_request *req, void *out)
607 {
608 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
609 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
610 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
611 
612 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
613 	rctx->fallback_req.base.flags = req->base.flags
614 		& CRYPTO_TFM_REQ_MAY_SLEEP;
615 
616 	return crypto_ahash_export(&rctx->fallback_req, out);
617 }
618 
619 static int img_hash_digest(struct ahash_request *req)
620 {
621 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
622 	struct img_hash_ctx *tctx = crypto_ahash_ctx(tfm);
623 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
624 	struct img_hash_dev *hdev = NULL;
625 	struct img_hash_dev *tmp;
626 	int err;
627 
628 	spin_lock(&img_hash.lock);
629 	if (!tctx->hdev) {
630 		list_for_each_entry(tmp, &img_hash.dev_list, list) {
631 			hdev = tmp;
632 			break;
633 		}
634 		tctx->hdev = hdev;
635 
636 	} else {
637 		hdev = tctx->hdev;
638 	}
639 
640 	spin_unlock(&img_hash.lock);
641 	ctx->hdev = hdev;
642 	ctx->flags = 0;
643 	ctx->digsize = crypto_ahash_digestsize(tfm);
644 
645 	switch (ctx->digsize) {
646 	case SHA1_DIGEST_SIZE:
647 		ctx->flags |= DRIVER_FLAGS_SHA1;
648 		break;
649 	case SHA256_DIGEST_SIZE:
650 		ctx->flags |= DRIVER_FLAGS_SHA256;
651 		break;
652 	case SHA224_DIGEST_SIZE:
653 		ctx->flags |= DRIVER_FLAGS_SHA224;
654 		break;
655 	case MD5_DIGEST_SIZE:
656 		ctx->flags |= DRIVER_FLAGS_MD5;
657 		break;
658 	default:
659 		return -EINVAL;
660 	}
661 
662 	ctx->bufcnt = 0;
663 	ctx->offset = 0;
664 	ctx->sent = 0;
665 	ctx->total = req->nbytes;
666 	ctx->sg = req->src;
667 	ctx->sgfirst = req->src;
668 	ctx->nents = sg_nents(ctx->sg);
669 
670 	err = img_hash_handle_queue(tctx->hdev, req);
671 
672 	return err;
673 }
674 
675 static int img_hash_cra_init(struct crypto_tfm *tfm, const char *alg_name)
676 {
677 	struct img_hash_ctx *ctx = crypto_tfm_ctx(tfm);
678 	int err = -ENOMEM;
679 
680 	ctx->fallback = crypto_alloc_ahash(alg_name, 0,
681 					   CRYPTO_ALG_NEED_FALLBACK);
682 	if (IS_ERR(ctx->fallback)) {
683 		pr_err("img_hash: Could not load fallback driver.\n");
684 		err = PTR_ERR(ctx->fallback);
685 		goto err;
686 	}
687 	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
688 				 sizeof(struct img_hash_request_ctx) +
689 				 crypto_ahash_reqsize(ctx->fallback) +
690 				 IMG_HASH_DMA_THRESHOLD);
691 
692 	return 0;
693 
694 err:
695 	return err;
696 }
697 
698 static int img_hash_cra_md5_init(struct crypto_tfm *tfm)
699 {
700 	return img_hash_cra_init(tfm, "md5-generic");
701 }
702 
703 static int img_hash_cra_sha1_init(struct crypto_tfm *tfm)
704 {
705 	return img_hash_cra_init(tfm, "sha1-generic");
706 }
707 
708 static int img_hash_cra_sha224_init(struct crypto_tfm *tfm)
709 {
710 	return img_hash_cra_init(tfm, "sha224-generic");
711 }
712 
713 static int img_hash_cra_sha256_init(struct crypto_tfm *tfm)
714 {
715 	return img_hash_cra_init(tfm, "sha256-generic");
716 }
717 
718 static void img_hash_cra_exit(struct crypto_tfm *tfm)
719 {
720 	struct img_hash_ctx *tctx = crypto_tfm_ctx(tfm);
721 
722 	crypto_free_ahash(tctx->fallback);
723 }
724 
725 static irqreturn_t img_irq_handler(int irq, void *dev_id)
726 {
727 	struct img_hash_dev *hdev = dev_id;
728 	u32 reg;
729 
730 	reg = img_hash_read(hdev, CR_INTSTAT);
731 	img_hash_write(hdev, CR_INTCLEAR, reg);
732 
733 	if (reg & CR_INT_NEW_RESULTS_SET) {
734 		dev_dbg(hdev->dev, "IRQ CR_INT_NEW_RESULTS_SET\n");
735 		if (DRIVER_FLAGS_BUSY & hdev->flags) {
736 			hdev->flags |= DRIVER_FLAGS_OUTPUT_READY;
737 			if (!(DRIVER_FLAGS_CPU & hdev->flags))
738 				hdev->flags |= DRIVER_FLAGS_DMA_READY;
739 			tasklet_schedule(&hdev->done_task);
740 		} else {
741 			dev_warn(hdev->dev,
742 				 "HASH interrupt when no active requests.\n");
743 		}
744 	} else if (reg & CR_INT_RESULTS_AVAILABLE) {
745 		dev_warn(hdev->dev,
746 			 "IRQ triggered before the hash had completed\n");
747 	} else if (reg & CR_INT_RESULT_READ_ERR) {
748 		dev_warn(hdev->dev,
749 			 "Attempt to read from an empty result queue\n");
750 	} else if (reg & CR_INT_MESSAGE_WRITE_ERROR) {
751 		dev_warn(hdev->dev,
752 			 "Data written before the hardware was configured\n");
753 	}
754 	return IRQ_HANDLED;
755 }
756 
757 static struct ahash_alg img_algs[] = {
758 	{
759 		.init = img_hash_init,
760 		.update = img_hash_update,
761 		.final = img_hash_final,
762 		.finup = img_hash_finup,
763 		.export = img_hash_export,
764 		.import = img_hash_import,
765 		.digest = img_hash_digest,
766 		.halg = {
767 			.digestsize = MD5_DIGEST_SIZE,
768 			.statesize = sizeof(struct md5_state),
769 			.base = {
770 				.cra_name = "md5",
771 				.cra_driver_name = "img-md5",
772 				.cra_priority = 300,
773 				.cra_flags =
774 				CRYPTO_ALG_ASYNC |
775 				CRYPTO_ALG_NEED_FALLBACK,
776 				.cra_blocksize = MD5_HMAC_BLOCK_SIZE,
777 				.cra_ctxsize = sizeof(struct img_hash_ctx),
778 				.cra_init = img_hash_cra_md5_init,
779 				.cra_exit = img_hash_cra_exit,
780 				.cra_module = THIS_MODULE,
781 			}
782 		}
783 	},
784 	{
785 		.init = img_hash_init,
786 		.update = img_hash_update,
787 		.final = img_hash_final,
788 		.finup = img_hash_finup,
789 		.export = img_hash_export,
790 		.import = img_hash_import,
791 		.digest = img_hash_digest,
792 		.halg = {
793 			.digestsize = SHA1_DIGEST_SIZE,
794 			.statesize = sizeof(struct sha1_state),
795 			.base = {
796 				.cra_name = "sha1",
797 				.cra_driver_name = "img-sha1",
798 				.cra_priority = 300,
799 				.cra_flags =
800 				CRYPTO_ALG_ASYNC |
801 				CRYPTO_ALG_NEED_FALLBACK,
802 				.cra_blocksize = SHA1_BLOCK_SIZE,
803 				.cra_ctxsize = sizeof(struct img_hash_ctx),
804 				.cra_init = img_hash_cra_sha1_init,
805 				.cra_exit = img_hash_cra_exit,
806 				.cra_module = THIS_MODULE,
807 			}
808 		}
809 	},
810 	{
811 		.init = img_hash_init,
812 		.update = img_hash_update,
813 		.final = img_hash_final,
814 		.finup = img_hash_finup,
815 		.export = img_hash_export,
816 		.import = img_hash_import,
817 		.digest = img_hash_digest,
818 		.halg = {
819 			.digestsize = SHA224_DIGEST_SIZE,
820 			.statesize = sizeof(struct sha256_state),
821 			.base = {
822 				.cra_name = "sha224",
823 				.cra_driver_name = "img-sha224",
824 				.cra_priority = 300,
825 				.cra_flags =
826 				CRYPTO_ALG_ASYNC |
827 				CRYPTO_ALG_NEED_FALLBACK,
828 				.cra_blocksize = SHA224_BLOCK_SIZE,
829 				.cra_ctxsize = sizeof(struct img_hash_ctx),
830 				.cra_init = img_hash_cra_sha224_init,
831 				.cra_exit = img_hash_cra_exit,
832 				.cra_module = THIS_MODULE,
833 			}
834 		}
835 	},
836 	{
837 		.init = img_hash_init,
838 		.update = img_hash_update,
839 		.final = img_hash_final,
840 		.finup = img_hash_finup,
841 		.export = img_hash_export,
842 		.import = img_hash_import,
843 		.digest = img_hash_digest,
844 		.halg = {
845 			.digestsize = SHA256_DIGEST_SIZE,
846 			.statesize = sizeof(struct sha256_state),
847 			.base = {
848 				.cra_name = "sha256",
849 				.cra_driver_name = "img-sha256",
850 				.cra_priority = 300,
851 				.cra_flags =
852 				CRYPTO_ALG_ASYNC |
853 				CRYPTO_ALG_NEED_FALLBACK,
854 				.cra_blocksize = SHA256_BLOCK_SIZE,
855 				.cra_ctxsize = sizeof(struct img_hash_ctx),
856 				.cra_init = img_hash_cra_sha256_init,
857 				.cra_exit = img_hash_cra_exit,
858 				.cra_module = THIS_MODULE,
859 			}
860 		}
861 	}
862 };
863 
864 static int img_register_algs(struct img_hash_dev *hdev)
865 {
866 	int i, err;
867 
868 	for (i = 0; i < ARRAY_SIZE(img_algs); i++) {
869 		err = crypto_register_ahash(&img_algs[i]);
870 		if (err)
871 			goto err_reg;
872 	}
873 	return 0;
874 
875 err_reg:
876 	for (; i--; )
877 		crypto_unregister_ahash(&img_algs[i]);
878 
879 	return err;
880 }
881 
882 static int img_unregister_algs(struct img_hash_dev *hdev)
883 {
884 	int i;
885 
886 	for (i = 0; i < ARRAY_SIZE(img_algs); i++)
887 		crypto_unregister_ahash(&img_algs[i]);
888 	return 0;
889 }
890 
891 static void img_hash_done_task(unsigned long data)
892 {
893 	struct img_hash_dev *hdev = (struct img_hash_dev *)data;
894 	int err = 0;
895 
896 	if (hdev->err == -EINVAL) {
897 		err = hdev->err;
898 		goto finish;
899 	}
900 
901 	if (!(DRIVER_FLAGS_BUSY & hdev->flags)) {
902 		img_hash_handle_queue(hdev, NULL);
903 		return;
904 	}
905 
906 	if (DRIVER_FLAGS_CPU & hdev->flags) {
907 		if (DRIVER_FLAGS_OUTPUT_READY & hdev->flags) {
908 			hdev->flags &= ~DRIVER_FLAGS_OUTPUT_READY;
909 			goto finish;
910 		}
911 	} else if (DRIVER_FLAGS_DMA_READY & hdev->flags) {
912 		if (DRIVER_FLAGS_DMA_ACTIVE & hdev->flags) {
913 			hdev->flags &= ~DRIVER_FLAGS_DMA_ACTIVE;
914 			img_hash_write_via_dma_stop(hdev);
915 			if (hdev->err) {
916 				err = hdev->err;
917 				goto finish;
918 			}
919 		}
920 		if (DRIVER_FLAGS_OUTPUT_READY & hdev->flags) {
921 			hdev->flags &= ~(DRIVER_FLAGS_DMA_READY |
922 					DRIVER_FLAGS_OUTPUT_READY);
923 			goto finish;
924 		}
925 	}
926 	return;
927 
928 finish:
929 	img_hash_finish_req(hdev->req, err);
930 }
931 
932 static const struct of_device_id img_hash_match[] = {
933 	{ .compatible = "img,hash-accelerator" },
934 	{}
935 };
936 MODULE_DEVICE_TABLE(of, img_hash_match);
937 
938 static int img_hash_probe(struct platform_device *pdev)
939 {
940 	struct img_hash_dev *hdev;
941 	struct device *dev = &pdev->dev;
942 	struct resource *hash_res;
943 	int	irq;
944 	int err;
945 
946 	hdev = devm_kzalloc(dev, sizeof(*hdev), GFP_KERNEL);
947 	if (hdev == NULL)
948 		return -ENOMEM;
949 
950 	spin_lock_init(&hdev->lock);
951 
952 	hdev->dev = dev;
953 
954 	platform_set_drvdata(pdev, hdev);
955 
956 	INIT_LIST_HEAD(&hdev->list);
957 
958 	tasklet_init(&hdev->done_task, img_hash_done_task, (unsigned long)hdev);
959 	tasklet_init(&hdev->dma_task, img_hash_dma_task, (unsigned long)hdev);
960 
961 	crypto_init_queue(&hdev->queue, IMG_HASH_QUEUE_LENGTH);
962 
963 	/* Register bank */
964 	hash_res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
965 
966 	hdev->io_base = devm_ioremap_resource(dev, hash_res);
967 	if (IS_ERR(hdev->io_base)) {
968 		err = PTR_ERR(hdev->io_base);
969 		dev_err(dev, "can't ioremap, returned %d\n", err);
970 
971 		goto res_err;
972 	}
973 
974 	/* Write port (DMA or CPU) */
975 	hash_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
976 	hdev->cpu_addr = devm_ioremap_resource(dev, hash_res);
977 	if (IS_ERR(hdev->cpu_addr)) {
978 		dev_err(dev, "can't ioremap write port\n");
979 		err = PTR_ERR(hdev->cpu_addr);
980 		goto res_err;
981 	}
982 	hdev->bus_addr = hash_res->start;
983 
984 	irq = platform_get_irq(pdev, 0);
985 	if (irq < 0) {
986 		dev_err(dev, "no IRQ resource info\n");
987 		err = irq;
988 		goto res_err;
989 	}
990 
991 	err = devm_request_irq(dev, irq, img_irq_handler, 0,
992 			       dev_name(dev), hdev);
993 	if (err) {
994 		dev_err(dev, "unable to request irq\n");
995 		goto res_err;
996 	}
997 	dev_dbg(dev, "using IRQ channel %d\n", irq);
998 
999 	hdev->hash_clk = devm_clk_get(&pdev->dev, "hash");
1000 	if (IS_ERR(hdev->hash_clk)) {
1001 		dev_err(dev, "clock initialization failed.\n");
1002 		err = PTR_ERR(hdev->hash_clk);
1003 		goto res_err;
1004 	}
1005 
1006 	hdev->sys_clk = devm_clk_get(&pdev->dev, "sys");
1007 	if (IS_ERR(hdev->sys_clk)) {
1008 		dev_err(dev, "clock initialization failed.\n");
1009 		err = PTR_ERR(hdev->sys_clk);
1010 		goto res_err;
1011 	}
1012 
1013 	err = clk_prepare_enable(hdev->hash_clk);
1014 	if (err)
1015 		goto res_err;
1016 
1017 	err = clk_prepare_enable(hdev->sys_clk);
1018 	if (err)
1019 		goto clk_err;
1020 
1021 	err = img_hash_dma_init(hdev);
1022 	if (err)
1023 		goto dma_err;
1024 
1025 	dev_dbg(dev, "using %s for DMA transfers\n",
1026 		dma_chan_name(hdev->dma_lch));
1027 
1028 	spin_lock(&img_hash.lock);
1029 	list_add_tail(&hdev->list, &img_hash.dev_list);
1030 	spin_unlock(&img_hash.lock);
1031 
1032 	err = img_register_algs(hdev);
1033 	if (err)
1034 		goto err_algs;
1035 	dev_info(dev, "Img MD5/SHA1/SHA224/SHA256 Hardware accelerator initialized\n");
1036 
1037 	return 0;
1038 
1039 err_algs:
1040 	spin_lock(&img_hash.lock);
1041 	list_del(&hdev->list);
1042 	spin_unlock(&img_hash.lock);
1043 	dma_release_channel(hdev->dma_lch);
1044 dma_err:
1045 	clk_disable_unprepare(hdev->sys_clk);
1046 clk_err:
1047 	clk_disable_unprepare(hdev->hash_clk);
1048 res_err:
1049 	tasklet_kill(&hdev->done_task);
1050 	tasklet_kill(&hdev->dma_task);
1051 
1052 	return err;
1053 }
1054 
1055 static int img_hash_remove(struct platform_device *pdev)
1056 {
1057 	struct img_hash_dev *hdev;
1058 
1059 	hdev = platform_get_drvdata(pdev);
1060 	spin_lock(&img_hash.lock);
1061 	list_del(&hdev->list);
1062 	spin_unlock(&img_hash.lock);
1063 
1064 	img_unregister_algs(hdev);
1065 
1066 	tasklet_kill(&hdev->done_task);
1067 	tasklet_kill(&hdev->dma_task);
1068 
1069 	dma_release_channel(hdev->dma_lch);
1070 
1071 	clk_disable_unprepare(hdev->hash_clk);
1072 	clk_disable_unprepare(hdev->sys_clk);
1073 
1074 	return 0;
1075 }
1076 
1077 #ifdef CONFIG_PM_SLEEP
1078 static int img_hash_suspend(struct device *dev)
1079 {
1080 	struct img_hash_dev *hdev = dev_get_drvdata(dev);
1081 
1082 	clk_disable_unprepare(hdev->hash_clk);
1083 	clk_disable_unprepare(hdev->sys_clk);
1084 
1085 	return 0;
1086 }
1087 
1088 static int img_hash_resume(struct device *dev)
1089 {
1090 	struct img_hash_dev *hdev = dev_get_drvdata(dev);
1091 	int ret;
1092 
1093 	ret = clk_prepare_enable(hdev->hash_clk);
1094 	if (ret)
1095 		return ret;
1096 
1097 	ret = clk_prepare_enable(hdev->sys_clk);
1098 	if (ret) {
1099 		clk_disable_unprepare(hdev->hash_clk);
1100 		return ret;
1101 	}
1102 
1103 	return 0;
1104 }
1105 #endif /* CONFIG_PM_SLEEP */
1106 
1107 static const struct dev_pm_ops img_hash_pm_ops = {
1108 	SET_SYSTEM_SLEEP_PM_OPS(img_hash_suspend, img_hash_resume)
1109 };
1110 
1111 static struct platform_driver img_hash_driver = {
1112 	.probe		= img_hash_probe,
1113 	.remove		= img_hash_remove,
1114 	.driver		= {
1115 		.name	= "img-hash-accelerator",
1116 		.pm	= &img_hash_pm_ops,
1117 		.of_match_table	= of_match_ptr(img_hash_match),
1118 	}
1119 };
1120 module_platform_driver(img_hash_driver);
1121 
1122 MODULE_LICENSE("GPL v2");
1123 MODULE_DESCRIPTION("Imgtec SHA1/224/256 & MD5 hw accelerator driver");
1124 MODULE_AUTHOR("Will Thomas.");
1125 MODULE_AUTHOR("James Hartley <james.hartley@imgtec.com>");
1126