xref: /openbmc/linux/drivers/crypto/img-hash.c (revision 405db98b)
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 u32 img_hash_read_result_queue(struct img_hash_dev *hdev)
161 {
162 	return be32_to_cpu(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 	u32 *hash = (u32 *)ctx->digest;
287 	int i;
288 
289 	for (i = (ctx->digsize / sizeof(u32)) - 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 		req->base.complete(&req->base, 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 = ahash_request_ctx(hdev->req);
362 	u8 *addr;
363 	size_t nbytes, bleft, wsend, len, tbc;
364 	struct scatterlist tsg;
365 
366 	if (!hdev->req || !ctx->sg)
367 		return;
368 
369 	addr = sg_virt(ctx->sg);
370 	nbytes = ctx->sg->length - ctx->offset;
371 
372 	/*
373 	 * The hash accelerator does not support a data valid mask. This means
374 	 * that if each dma (i.e. per page) is not a multiple of 4 bytes, the
375 	 * padding bytes in the last word written by that dma would erroneously
376 	 * be included in the hash. To avoid this we round down the transfer,
377 	 * and add the excess to the start of the next dma. It does not matter
378 	 * that the final dma may not be a multiple of 4 bytes as the hashing
379 	 * block is programmed to accept the correct number of bytes.
380 	 */
381 
382 	bleft = nbytes % 4;
383 	wsend = (nbytes / 4);
384 
385 	if (wsend) {
386 		sg_init_one(&tsg, addr + ctx->offset, wsend * 4);
387 		if (img_hash_xmit_dma(hdev, &tsg)) {
388 			dev_err(hdev->dev, "DMA failed, falling back to CPU");
389 			ctx->flags |= DRIVER_FLAGS_CPU;
390 			hdev->err = 0;
391 			img_hash_xmit_cpu(hdev, addr + ctx->offset,
392 					  wsend * 4, 0);
393 			ctx->sent += wsend * 4;
394 			wsend = 0;
395 		} else {
396 			ctx->sent += wsend * 4;
397 		}
398 	}
399 
400 	if (bleft) {
401 		ctx->bufcnt = sg_pcopy_to_buffer(ctx->sgfirst, ctx->nents,
402 						 ctx->buffer, bleft, ctx->sent);
403 		tbc = 0;
404 		ctx->sg = sg_next(ctx->sg);
405 		while (ctx->sg && (ctx->bufcnt < 4)) {
406 			len = ctx->sg->length;
407 			if (likely(len > (4 - ctx->bufcnt)))
408 				len = 4 - ctx->bufcnt;
409 			tbc = sg_pcopy_to_buffer(ctx->sgfirst, ctx->nents,
410 						 ctx->buffer + ctx->bufcnt, len,
411 					ctx->sent + ctx->bufcnt);
412 			ctx->bufcnt += tbc;
413 			if (tbc >= ctx->sg->length) {
414 				ctx->sg = sg_next(ctx->sg);
415 				tbc = 0;
416 			}
417 		}
418 
419 		ctx->sent += ctx->bufcnt;
420 		ctx->offset = tbc;
421 
422 		if (!wsend)
423 			img_hash_dma_callback(hdev);
424 	} else {
425 		ctx->offset = 0;
426 		ctx->sg = sg_next(ctx->sg);
427 	}
428 }
429 
430 static int img_hash_write_via_dma_stop(struct img_hash_dev *hdev)
431 {
432 	struct img_hash_request_ctx *ctx = ahash_request_ctx(hdev->req);
433 
434 	if (ctx->flags & DRIVER_FLAGS_SG)
435 		dma_unmap_sg(hdev->dev, ctx->sg, ctx->dma_ct, DMA_TO_DEVICE);
436 
437 	return 0;
438 }
439 
440 static int img_hash_process_data(struct img_hash_dev *hdev)
441 {
442 	struct ahash_request *req = hdev->req;
443 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
444 	int err = 0;
445 
446 	ctx->bufcnt = 0;
447 
448 	if (req->nbytes >= IMG_HASH_DMA_THRESHOLD) {
449 		dev_dbg(hdev->dev, "process data request(%d bytes) using DMA\n",
450 			req->nbytes);
451 		err = img_hash_write_via_dma(hdev);
452 	} else {
453 		dev_dbg(hdev->dev, "process data request(%d bytes) using CPU\n",
454 			req->nbytes);
455 		err = img_hash_write_via_cpu(hdev);
456 	}
457 	return err;
458 }
459 
460 static int img_hash_hw_init(struct img_hash_dev *hdev)
461 {
462 	unsigned long long nbits;
463 	u32 u, l;
464 
465 	img_hash_write(hdev, CR_RESET, CR_RESET_SET);
466 	img_hash_write(hdev, CR_RESET, CR_RESET_UNSET);
467 	img_hash_write(hdev, CR_INTENAB, CR_INT_NEW_RESULTS_SET);
468 
469 	nbits = (u64)hdev->req->nbytes << 3;
470 	u = nbits >> 32;
471 	l = nbits;
472 	img_hash_write(hdev, CR_MESSAGE_LENGTH_H, u);
473 	img_hash_write(hdev, CR_MESSAGE_LENGTH_L, l);
474 
475 	if (!(DRIVER_FLAGS_INIT & hdev->flags)) {
476 		hdev->flags |= DRIVER_FLAGS_INIT;
477 		hdev->err = 0;
478 	}
479 	dev_dbg(hdev->dev, "hw initialized, nbits: %llx\n", nbits);
480 	return 0;
481 }
482 
483 static int img_hash_init(struct ahash_request *req)
484 {
485 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
486 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
487 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
488 
489 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
490 	rctx->fallback_req.base.flags =	req->base.flags
491 		& CRYPTO_TFM_REQ_MAY_SLEEP;
492 
493 	return crypto_ahash_init(&rctx->fallback_req);
494 }
495 
496 static int img_hash_handle_queue(struct img_hash_dev *hdev,
497 				 struct ahash_request *req)
498 {
499 	struct crypto_async_request *async_req, *backlog;
500 	struct img_hash_request_ctx *ctx;
501 	unsigned long flags;
502 	int err = 0, res = 0;
503 
504 	spin_lock_irqsave(&hdev->lock, flags);
505 
506 	if (req)
507 		res = ahash_enqueue_request(&hdev->queue, req);
508 
509 	if (DRIVER_FLAGS_BUSY & hdev->flags) {
510 		spin_unlock_irqrestore(&hdev->lock, flags);
511 		return res;
512 	}
513 
514 	backlog = crypto_get_backlog(&hdev->queue);
515 	async_req = crypto_dequeue_request(&hdev->queue);
516 	if (async_req)
517 		hdev->flags |= DRIVER_FLAGS_BUSY;
518 
519 	spin_unlock_irqrestore(&hdev->lock, flags);
520 
521 	if (!async_req)
522 		return res;
523 
524 	if (backlog)
525 		backlog->complete(backlog, -EINPROGRESS);
526 
527 	req = ahash_request_cast(async_req);
528 	hdev->req = req;
529 
530 	ctx = ahash_request_ctx(req);
531 
532 	dev_info(hdev->dev, "processing req, op: %lu, bytes: %d\n",
533 		 ctx->op, req->nbytes);
534 
535 	err = img_hash_hw_init(hdev);
536 
537 	if (!err)
538 		err = img_hash_process_data(hdev);
539 
540 	if (err != -EINPROGRESS) {
541 		/* done_task will not finish so do it here */
542 		img_hash_finish_req(req, err);
543 	}
544 	return res;
545 }
546 
547 static int img_hash_update(struct ahash_request *req)
548 {
549 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
550 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
551 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
552 
553 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
554 	rctx->fallback_req.base.flags = req->base.flags
555 		& CRYPTO_TFM_REQ_MAY_SLEEP;
556 	rctx->fallback_req.nbytes = req->nbytes;
557 	rctx->fallback_req.src = req->src;
558 
559 	return crypto_ahash_update(&rctx->fallback_req);
560 }
561 
562 static int img_hash_final(struct ahash_request *req)
563 {
564 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
565 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
566 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
567 
568 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
569 	rctx->fallback_req.base.flags = req->base.flags
570 		& CRYPTO_TFM_REQ_MAY_SLEEP;
571 	rctx->fallback_req.result = req->result;
572 
573 	return crypto_ahash_final(&rctx->fallback_req);
574 }
575 
576 static int img_hash_finup(struct ahash_request *req)
577 {
578 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
579 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
580 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
581 
582 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
583 	rctx->fallback_req.base.flags = req->base.flags
584 		& CRYPTO_TFM_REQ_MAY_SLEEP;
585 	rctx->fallback_req.nbytes = req->nbytes;
586 	rctx->fallback_req.src = req->src;
587 	rctx->fallback_req.result = req->result;
588 
589 	return crypto_ahash_finup(&rctx->fallback_req);
590 }
591 
592 static int img_hash_import(struct ahash_request *req, const void *in)
593 {
594 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
595 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
596 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
597 
598 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
599 	rctx->fallback_req.base.flags = req->base.flags
600 		& CRYPTO_TFM_REQ_MAY_SLEEP;
601 
602 	return crypto_ahash_import(&rctx->fallback_req, in);
603 }
604 
605 static int img_hash_export(struct ahash_request *req, void *out)
606 {
607 	struct img_hash_request_ctx *rctx = ahash_request_ctx(req);
608 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
609 	struct img_hash_ctx *ctx = crypto_ahash_ctx(tfm);
610 
611 	ahash_request_set_tfm(&rctx->fallback_req, ctx->fallback);
612 	rctx->fallback_req.base.flags = req->base.flags
613 		& CRYPTO_TFM_REQ_MAY_SLEEP;
614 
615 	return crypto_ahash_export(&rctx->fallback_req, out);
616 }
617 
618 static int img_hash_digest(struct ahash_request *req)
619 {
620 	struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
621 	struct img_hash_ctx *tctx = crypto_ahash_ctx(tfm);
622 	struct img_hash_request_ctx *ctx = ahash_request_ctx(req);
623 	struct img_hash_dev *hdev = NULL;
624 	struct img_hash_dev *tmp;
625 	int err;
626 
627 	spin_lock(&img_hash.lock);
628 	if (!tctx->hdev) {
629 		list_for_each_entry(tmp, &img_hash.dev_list, list) {
630 			hdev = tmp;
631 			break;
632 		}
633 		tctx->hdev = hdev;
634 
635 	} else {
636 		hdev = tctx->hdev;
637 	}
638 
639 	spin_unlock(&img_hash.lock);
640 	ctx->hdev = hdev;
641 	ctx->flags = 0;
642 	ctx->digsize = crypto_ahash_digestsize(tfm);
643 
644 	switch (ctx->digsize) {
645 	case SHA1_DIGEST_SIZE:
646 		ctx->flags |= DRIVER_FLAGS_SHA1;
647 		break;
648 	case SHA256_DIGEST_SIZE:
649 		ctx->flags |= DRIVER_FLAGS_SHA256;
650 		break;
651 	case SHA224_DIGEST_SIZE:
652 		ctx->flags |= DRIVER_FLAGS_SHA224;
653 		break;
654 	case MD5_DIGEST_SIZE:
655 		ctx->flags |= DRIVER_FLAGS_MD5;
656 		break;
657 	default:
658 		return -EINVAL;
659 	}
660 
661 	ctx->bufcnt = 0;
662 	ctx->offset = 0;
663 	ctx->sent = 0;
664 	ctx->total = req->nbytes;
665 	ctx->sg = req->src;
666 	ctx->sgfirst = req->src;
667 	ctx->nents = sg_nents(ctx->sg);
668 
669 	err = img_hash_handle_queue(tctx->hdev, req);
670 
671 	return err;
672 }
673 
674 static int img_hash_cra_init(struct crypto_tfm *tfm, const char *alg_name)
675 {
676 	struct img_hash_ctx *ctx = crypto_tfm_ctx(tfm);
677 
678 	ctx->fallback = crypto_alloc_ahash(alg_name, 0,
679 					   CRYPTO_ALG_NEED_FALLBACK);
680 	if (IS_ERR(ctx->fallback)) {
681 		pr_err("img_hash: Could not load fallback driver.\n");
682 		return PTR_ERR(ctx->fallback);
683 	}
684 	crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
685 				 sizeof(struct img_hash_request_ctx) +
686 				 crypto_ahash_reqsize(ctx->fallback) +
687 				 IMG_HASH_DMA_THRESHOLD);
688 
689 	return 0;
690 }
691 
692 static int img_hash_cra_md5_init(struct crypto_tfm *tfm)
693 {
694 	return img_hash_cra_init(tfm, "md5-generic");
695 }
696 
697 static int img_hash_cra_sha1_init(struct crypto_tfm *tfm)
698 {
699 	return img_hash_cra_init(tfm, "sha1-generic");
700 }
701 
702 static int img_hash_cra_sha224_init(struct crypto_tfm *tfm)
703 {
704 	return img_hash_cra_init(tfm, "sha224-generic");
705 }
706 
707 static int img_hash_cra_sha256_init(struct crypto_tfm *tfm)
708 {
709 	return img_hash_cra_init(tfm, "sha256-generic");
710 }
711 
712 static void img_hash_cra_exit(struct crypto_tfm *tfm)
713 {
714 	struct img_hash_ctx *tctx = crypto_tfm_ctx(tfm);
715 
716 	crypto_free_ahash(tctx->fallback);
717 }
718 
719 static irqreturn_t img_irq_handler(int irq, void *dev_id)
720 {
721 	struct img_hash_dev *hdev = dev_id;
722 	u32 reg;
723 
724 	reg = img_hash_read(hdev, CR_INTSTAT);
725 	img_hash_write(hdev, CR_INTCLEAR, reg);
726 
727 	if (reg & CR_INT_NEW_RESULTS_SET) {
728 		dev_dbg(hdev->dev, "IRQ CR_INT_NEW_RESULTS_SET\n");
729 		if (DRIVER_FLAGS_BUSY & hdev->flags) {
730 			hdev->flags |= DRIVER_FLAGS_OUTPUT_READY;
731 			if (!(DRIVER_FLAGS_CPU & hdev->flags))
732 				hdev->flags |= DRIVER_FLAGS_DMA_READY;
733 			tasklet_schedule(&hdev->done_task);
734 		} else {
735 			dev_warn(hdev->dev,
736 				 "HASH interrupt when no active requests.\n");
737 		}
738 	} else if (reg & CR_INT_RESULTS_AVAILABLE) {
739 		dev_warn(hdev->dev,
740 			 "IRQ triggered before the hash had completed\n");
741 	} else if (reg & CR_INT_RESULT_READ_ERR) {
742 		dev_warn(hdev->dev,
743 			 "Attempt to read from an empty result queue\n");
744 	} else if (reg & CR_INT_MESSAGE_WRITE_ERROR) {
745 		dev_warn(hdev->dev,
746 			 "Data written before the hardware was configured\n");
747 	}
748 	return IRQ_HANDLED;
749 }
750 
751 static struct ahash_alg img_algs[] = {
752 	{
753 		.init = img_hash_init,
754 		.update = img_hash_update,
755 		.final = img_hash_final,
756 		.finup = img_hash_finup,
757 		.export = img_hash_export,
758 		.import = img_hash_import,
759 		.digest = img_hash_digest,
760 		.halg = {
761 			.digestsize = MD5_DIGEST_SIZE,
762 			.statesize = sizeof(struct md5_state),
763 			.base = {
764 				.cra_name = "md5",
765 				.cra_driver_name = "img-md5",
766 				.cra_priority = 300,
767 				.cra_flags =
768 				CRYPTO_ALG_ASYNC |
769 				CRYPTO_ALG_NEED_FALLBACK,
770 				.cra_blocksize = MD5_HMAC_BLOCK_SIZE,
771 				.cra_ctxsize = sizeof(struct img_hash_ctx),
772 				.cra_init = img_hash_cra_md5_init,
773 				.cra_exit = img_hash_cra_exit,
774 				.cra_module = THIS_MODULE,
775 			}
776 		}
777 	},
778 	{
779 		.init = img_hash_init,
780 		.update = img_hash_update,
781 		.final = img_hash_final,
782 		.finup = img_hash_finup,
783 		.export = img_hash_export,
784 		.import = img_hash_import,
785 		.digest = img_hash_digest,
786 		.halg = {
787 			.digestsize = SHA1_DIGEST_SIZE,
788 			.statesize = sizeof(struct sha1_state),
789 			.base = {
790 				.cra_name = "sha1",
791 				.cra_driver_name = "img-sha1",
792 				.cra_priority = 300,
793 				.cra_flags =
794 				CRYPTO_ALG_ASYNC |
795 				CRYPTO_ALG_NEED_FALLBACK,
796 				.cra_blocksize = SHA1_BLOCK_SIZE,
797 				.cra_ctxsize = sizeof(struct img_hash_ctx),
798 				.cra_init = img_hash_cra_sha1_init,
799 				.cra_exit = img_hash_cra_exit,
800 				.cra_module = THIS_MODULE,
801 			}
802 		}
803 	},
804 	{
805 		.init = img_hash_init,
806 		.update = img_hash_update,
807 		.final = img_hash_final,
808 		.finup = img_hash_finup,
809 		.export = img_hash_export,
810 		.import = img_hash_import,
811 		.digest = img_hash_digest,
812 		.halg = {
813 			.digestsize = SHA224_DIGEST_SIZE,
814 			.statesize = sizeof(struct sha256_state),
815 			.base = {
816 				.cra_name = "sha224",
817 				.cra_driver_name = "img-sha224",
818 				.cra_priority = 300,
819 				.cra_flags =
820 				CRYPTO_ALG_ASYNC |
821 				CRYPTO_ALG_NEED_FALLBACK,
822 				.cra_blocksize = SHA224_BLOCK_SIZE,
823 				.cra_ctxsize = sizeof(struct img_hash_ctx),
824 				.cra_init = img_hash_cra_sha224_init,
825 				.cra_exit = img_hash_cra_exit,
826 				.cra_module = THIS_MODULE,
827 			}
828 		}
829 	},
830 	{
831 		.init = img_hash_init,
832 		.update = img_hash_update,
833 		.final = img_hash_final,
834 		.finup = img_hash_finup,
835 		.export = img_hash_export,
836 		.import = img_hash_import,
837 		.digest = img_hash_digest,
838 		.halg = {
839 			.digestsize = SHA256_DIGEST_SIZE,
840 			.statesize = sizeof(struct sha256_state),
841 			.base = {
842 				.cra_name = "sha256",
843 				.cra_driver_name = "img-sha256",
844 				.cra_priority = 300,
845 				.cra_flags =
846 				CRYPTO_ALG_ASYNC |
847 				CRYPTO_ALG_NEED_FALLBACK,
848 				.cra_blocksize = SHA256_BLOCK_SIZE,
849 				.cra_ctxsize = sizeof(struct img_hash_ctx),
850 				.cra_init = img_hash_cra_sha256_init,
851 				.cra_exit = img_hash_cra_exit,
852 				.cra_module = THIS_MODULE,
853 			}
854 		}
855 	}
856 };
857 
858 static int img_register_algs(struct img_hash_dev *hdev)
859 {
860 	int i, err;
861 
862 	for (i = 0; i < ARRAY_SIZE(img_algs); i++) {
863 		err = crypto_register_ahash(&img_algs[i]);
864 		if (err)
865 			goto err_reg;
866 	}
867 	return 0;
868 
869 err_reg:
870 	for (; i--; )
871 		crypto_unregister_ahash(&img_algs[i]);
872 
873 	return err;
874 }
875 
876 static int img_unregister_algs(struct img_hash_dev *hdev)
877 {
878 	int i;
879 
880 	for (i = 0; i < ARRAY_SIZE(img_algs); i++)
881 		crypto_unregister_ahash(&img_algs[i]);
882 	return 0;
883 }
884 
885 static void img_hash_done_task(unsigned long data)
886 {
887 	struct img_hash_dev *hdev = (struct img_hash_dev *)data;
888 	int err = 0;
889 
890 	if (hdev->err == -EINVAL) {
891 		err = hdev->err;
892 		goto finish;
893 	}
894 
895 	if (!(DRIVER_FLAGS_BUSY & hdev->flags)) {
896 		img_hash_handle_queue(hdev, NULL);
897 		return;
898 	}
899 
900 	if (DRIVER_FLAGS_CPU & hdev->flags) {
901 		if (DRIVER_FLAGS_OUTPUT_READY & hdev->flags) {
902 			hdev->flags &= ~DRIVER_FLAGS_OUTPUT_READY;
903 			goto finish;
904 		}
905 	} else if (DRIVER_FLAGS_DMA_READY & hdev->flags) {
906 		if (DRIVER_FLAGS_DMA_ACTIVE & hdev->flags) {
907 			hdev->flags &= ~DRIVER_FLAGS_DMA_ACTIVE;
908 			img_hash_write_via_dma_stop(hdev);
909 			if (hdev->err) {
910 				err = hdev->err;
911 				goto finish;
912 			}
913 		}
914 		if (DRIVER_FLAGS_OUTPUT_READY & hdev->flags) {
915 			hdev->flags &= ~(DRIVER_FLAGS_DMA_READY |
916 					DRIVER_FLAGS_OUTPUT_READY);
917 			goto finish;
918 		}
919 	}
920 	return;
921 
922 finish:
923 	img_hash_finish_req(hdev->req, err);
924 }
925 
926 static const struct of_device_id img_hash_match[] = {
927 	{ .compatible = "img,hash-accelerator" },
928 	{}
929 };
930 MODULE_DEVICE_TABLE(of, img_hash_match);
931 
932 static int img_hash_probe(struct platform_device *pdev)
933 {
934 	struct img_hash_dev *hdev;
935 	struct device *dev = &pdev->dev;
936 	struct resource *hash_res;
937 	int	irq;
938 	int err;
939 
940 	hdev = devm_kzalloc(dev, sizeof(*hdev), GFP_KERNEL);
941 	if (hdev == NULL)
942 		return -ENOMEM;
943 
944 	spin_lock_init(&hdev->lock);
945 
946 	hdev->dev = dev;
947 
948 	platform_set_drvdata(pdev, hdev);
949 
950 	INIT_LIST_HEAD(&hdev->list);
951 
952 	tasklet_init(&hdev->done_task, img_hash_done_task, (unsigned long)hdev);
953 	tasklet_init(&hdev->dma_task, img_hash_dma_task, (unsigned long)hdev);
954 
955 	crypto_init_queue(&hdev->queue, IMG_HASH_QUEUE_LENGTH);
956 
957 	/* Register bank */
958 	hdev->io_base = devm_platform_ioremap_resource(pdev, 0);
959 	if (IS_ERR(hdev->io_base)) {
960 		err = PTR_ERR(hdev->io_base);
961 		goto res_err;
962 	}
963 
964 	/* Write port (DMA or CPU) */
965 	hash_res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
966 	hdev->cpu_addr = devm_ioremap_resource(dev, hash_res);
967 	if (IS_ERR(hdev->cpu_addr)) {
968 		err = PTR_ERR(hdev->cpu_addr);
969 		goto res_err;
970 	}
971 	hdev->bus_addr = hash_res->start;
972 
973 	irq = platform_get_irq(pdev, 0);
974 	if (irq < 0) {
975 		err = irq;
976 		goto res_err;
977 	}
978 
979 	err = devm_request_irq(dev, irq, img_irq_handler, 0,
980 			       dev_name(dev), hdev);
981 	if (err) {
982 		dev_err(dev, "unable to request irq\n");
983 		goto res_err;
984 	}
985 	dev_dbg(dev, "using IRQ channel %d\n", irq);
986 
987 	hdev->hash_clk = devm_clk_get(&pdev->dev, "hash");
988 	if (IS_ERR(hdev->hash_clk)) {
989 		dev_err(dev, "clock initialization failed.\n");
990 		err = PTR_ERR(hdev->hash_clk);
991 		goto res_err;
992 	}
993 
994 	hdev->sys_clk = devm_clk_get(&pdev->dev, "sys");
995 	if (IS_ERR(hdev->sys_clk)) {
996 		dev_err(dev, "clock initialization failed.\n");
997 		err = PTR_ERR(hdev->sys_clk);
998 		goto res_err;
999 	}
1000 
1001 	err = clk_prepare_enable(hdev->hash_clk);
1002 	if (err)
1003 		goto res_err;
1004 
1005 	err = clk_prepare_enable(hdev->sys_clk);
1006 	if (err)
1007 		goto clk_err;
1008 
1009 	err = img_hash_dma_init(hdev);
1010 	if (err)
1011 		goto dma_err;
1012 
1013 	dev_dbg(dev, "using %s for DMA transfers\n",
1014 		dma_chan_name(hdev->dma_lch));
1015 
1016 	spin_lock(&img_hash.lock);
1017 	list_add_tail(&hdev->list, &img_hash.dev_list);
1018 	spin_unlock(&img_hash.lock);
1019 
1020 	err = img_register_algs(hdev);
1021 	if (err)
1022 		goto err_algs;
1023 	dev_info(dev, "Img MD5/SHA1/SHA224/SHA256 Hardware accelerator initialized\n");
1024 
1025 	return 0;
1026 
1027 err_algs:
1028 	spin_lock(&img_hash.lock);
1029 	list_del(&hdev->list);
1030 	spin_unlock(&img_hash.lock);
1031 	dma_release_channel(hdev->dma_lch);
1032 dma_err:
1033 	clk_disable_unprepare(hdev->sys_clk);
1034 clk_err:
1035 	clk_disable_unprepare(hdev->hash_clk);
1036 res_err:
1037 	tasklet_kill(&hdev->done_task);
1038 	tasklet_kill(&hdev->dma_task);
1039 
1040 	return err;
1041 }
1042 
1043 static int img_hash_remove(struct platform_device *pdev)
1044 {
1045 	struct img_hash_dev *hdev;
1046 
1047 	hdev = platform_get_drvdata(pdev);
1048 	spin_lock(&img_hash.lock);
1049 	list_del(&hdev->list);
1050 	spin_unlock(&img_hash.lock);
1051 
1052 	img_unregister_algs(hdev);
1053 
1054 	tasklet_kill(&hdev->done_task);
1055 	tasklet_kill(&hdev->dma_task);
1056 
1057 	dma_release_channel(hdev->dma_lch);
1058 
1059 	clk_disable_unprepare(hdev->hash_clk);
1060 	clk_disable_unprepare(hdev->sys_clk);
1061 
1062 	return 0;
1063 }
1064 
1065 #ifdef CONFIG_PM_SLEEP
1066 static int img_hash_suspend(struct device *dev)
1067 {
1068 	struct img_hash_dev *hdev = dev_get_drvdata(dev);
1069 
1070 	clk_disable_unprepare(hdev->hash_clk);
1071 	clk_disable_unprepare(hdev->sys_clk);
1072 
1073 	return 0;
1074 }
1075 
1076 static int img_hash_resume(struct device *dev)
1077 {
1078 	struct img_hash_dev *hdev = dev_get_drvdata(dev);
1079 	int ret;
1080 
1081 	ret = clk_prepare_enable(hdev->hash_clk);
1082 	if (ret)
1083 		return ret;
1084 
1085 	ret = clk_prepare_enable(hdev->sys_clk);
1086 	if (ret) {
1087 		clk_disable_unprepare(hdev->hash_clk);
1088 		return ret;
1089 	}
1090 
1091 	return 0;
1092 }
1093 #endif /* CONFIG_PM_SLEEP */
1094 
1095 static const struct dev_pm_ops img_hash_pm_ops = {
1096 	SET_SYSTEM_SLEEP_PM_OPS(img_hash_suspend, img_hash_resume)
1097 };
1098 
1099 static struct platform_driver img_hash_driver = {
1100 	.probe		= img_hash_probe,
1101 	.remove		= img_hash_remove,
1102 	.driver		= {
1103 		.name	= "img-hash-accelerator",
1104 		.pm	= &img_hash_pm_ops,
1105 		.of_match_table	= of_match_ptr(img_hash_match),
1106 	}
1107 };
1108 module_platform_driver(img_hash_driver);
1109 
1110 MODULE_LICENSE("GPL v2");
1111 MODULE_DESCRIPTION("Imgtec SHA1/224/256 & MD5 hw accelerator driver");
1112 MODULE_AUTHOR("Will Thomas.");
1113 MODULE_AUTHOR("James Hartley <james.hartley@imgtec.com>");
1114