xref: /linux/drivers/crypto/s5p-sss.c (revision fbc872c38c8fed31948c85683b5326ee5ab9fccc)
1 /*
2  * Cryptographic API.
3  *
4  * Support for Samsung S5PV210 HW acceleration.
5  *
6  * Copyright (C) 2011 NetUP Inc. All rights reserved.
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as published
10  * by the Free Software Foundation.
11  *
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/crypto.h>
16 #include <linux/dma-mapping.h>
17 #include <linux/err.h>
18 #include <linux/errno.h>
19 #include <linux/init.h>
20 #include <linux/interrupt.h>
21 #include <linux/io.h>
22 #include <linux/kernel.h>
23 #include <linux/module.h>
24 #include <linux/of.h>
25 #include <linux/platform_device.h>
26 #include <linux/scatterlist.h>
27 
28 #include <crypto/ctr.h>
29 #include <crypto/aes.h>
30 #include <crypto/algapi.h>
31 #include <crypto/scatterwalk.h>
32 
33 #define _SBF(s, v)                      ((v) << (s))
34 
35 /* Feed control registers */
36 #define SSS_REG_FCINTSTAT               0x0000
37 #define SSS_FCINTSTAT_BRDMAINT          BIT(3)
38 #define SSS_FCINTSTAT_BTDMAINT          BIT(2)
39 #define SSS_FCINTSTAT_HRDMAINT          BIT(1)
40 #define SSS_FCINTSTAT_PKDMAINT          BIT(0)
41 
42 #define SSS_REG_FCINTENSET              0x0004
43 #define SSS_FCINTENSET_BRDMAINTENSET    BIT(3)
44 #define SSS_FCINTENSET_BTDMAINTENSET    BIT(2)
45 #define SSS_FCINTENSET_HRDMAINTENSET    BIT(1)
46 #define SSS_FCINTENSET_PKDMAINTENSET    BIT(0)
47 
48 #define SSS_REG_FCINTENCLR              0x0008
49 #define SSS_FCINTENCLR_BRDMAINTENCLR    BIT(3)
50 #define SSS_FCINTENCLR_BTDMAINTENCLR    BIT(2)
51 #define SSS_FCINTENCLR_HRDMAINTENCLR    BIT(1)
52 #define SSS_FCINTENCLR_PKDMAINTENCLR    BIT(0)
53 
54 #define SSS_REG_FCINTPEND               0x000C
55 #define SSS_FCINTPEND_BRDMAINTP         BIT(3)
56 #define SSS_FCINTPEND_BTDMAINTP         BIT(2)
57 #define SSS_FCINTPEND_HRDMAINTP         BIT(1)
58 #define SSS_FCINTPEND_PKDMAINTP         BIT(0)
59 
60 #define SSS_REG_FCFIFOSTAT              0x0010
61 #define SSS_FCFIFOSTAT_BRFIFOFUL        BIT(7)
62 #define SSS_FCFIFOSTAT_BRFIFOEMP        BIT(6)
63 #define SSS_FCFIFOSTAT_BTFIFOFUL        BIT(5)
64 #define SSS_FCFIFOSTAT_BTFIFOEMP        BIT(4)
65 #define SSS_FCFIFOSTAT_HRFIFOFUL        BIT(3)
66 #define SSS_FCFIFOSTAT_HRFIFOEMP        BIT(2)
67 #define SSS_FCFIFOSTAT_PKFIFOFUL        BIT(1)
68 #define SSS_FCFIFOSTAT_PKFIFOEMP        BIT(0)
69 
70 #define SSS_REG_FCFIFOCTRL              0x0014
71 #define SSS_FCFIFOCTRL_DESSEL           BIT(2)
72 #define SSS_HASHIN_INDEPENDENT          _SBF(0, 0x00)
73 #define SSS_HASHIN_CIPHER_INPUT         _SBF(0, 0x01)
74 #define SSS_HASHIN_CIPHER_OUTPUT        _SBF(0, 0x02)
75 
76 #define SSS_REG_FCBRDMAS                0x0020
77 #define SSS_REG_FCBRDMAL                0x0024
78 #define SSS_REG_FCBRDMAC                0x0028
79 #define SSS_FCBRDMAC_BYTESWAP           BIT(1)
80 #define SSS_FCBRDMAC_FLUSH              BIT(0)
81 
82 #define SSS_REG_FCBTDMAS                0x0030
83 #define SSS_REG_FCBTDMAL                0x0034
84 #define SSS_REG_FCBTDMAC                0x0038
85 #define SSS_FCBTDMAC_BYTESWAP           BIT(1)
86 #define SSS_FCBTDMAC_FLUSH              BIT(0)
87 
88 #define SSS_REG_FCHRDMAS                0x0040
89 #define SSS_REG_FCHRDMAL                0x0044
90 #define SSS_REG_FCHRDMAC                0x0048
91 #define SSS_FCHRDMAC_BYTESWAP           BIT(1)
92 #define SSS_FCHRDMAC_FLUSH              BIT(0)
93 
94 #define SSS_REG_FCPKDMAS                0x0050
95 #define SSS_REG_FCPKDMAL                0x0054
96 #define SSS_REG_FCPKDMAC                0x0058
97 #define SSS_FCPKDMAC_BYTESWAP           BIT(3)
98 #define SSS_FCPKDMAC_DESCEND            BIT(2)
99 #define SSS_FCPKDMAC_TRANSMIT           BIT(1)
100 #define SSS_FCPKDMAC_FLUSH              BIT(0)
101 
102 #define SSS_REG_FCPKDMAO                0x005C
103 
104 /* AES registers */
105 #define SSS_REG_AES_CONTROL		0x00
106 #define SSS_AES_BYTESWAP_DI             BIT(11)
107 #define SSS_AES_BYTESWAP_DO             BIT(10)
108 #define SSS_AES_BYTESWAP_IV             BIT(9)
109 #define SSS_AES_BYTESWAP_CNT            BIT(8)
110 #define SSS_AES_BYTESWAP_KEY            BIT(7)
111 #define SSS_AES_KEY_CHANGE_MODE         BIT(6)
112 #define SSS_AES_KEY_SIZE_128            _SBF(4, 0x00)
113 #define SSS_AES_KEY_SIZE_192            _SBF(4, 0x01)
114 #define SSS_AES_KEY_SIZE_256            _SBF(4, 0x02)
115 #define SSS_AES_FIFO_MODE               BIT(3)
116 #define SSS_AES_CHAIN_MODE_ECB          _SBF(1, 0x00)
117 #define SSS_AES_CHAIN_MODE_CBC          _SBF(1, 0x01)
118 #define SSS_AES_CHAIN_MODE_CTR          _SBF(1, 0x02)
119 #define SSS_AES_MODE_DECRYPT            BIT(0)
120 
121 #define SSS_REG_AES_STATUS		0x04
122 #define SSS_AES_BUSY                    BIT(2)
123 #define SSS_AES_INPUT_READY             BIT(1)
124 #define SSS_AES_OUTPUT_READY            BIT(0)
125 
126 #define SSS_REG_AES_IN_DATA(s)		(0x10 + (s << 2))
127 #define SSS_REG_AES_OUT_DATA(s)		(0x20 + (s << 2))
128 #define SSS_REG_AES_IV_DATA(s)		(0x30 + (s << 2))
129 #define SSS_REG_AES_CNT_DATA(s)		(0x40 + (s << 2))
130 #define SSS_REG_AES_KEY_DATA(s)		(0x80 + (s << 2))
131 
132 #define SSS_REG(dev, reg)               ((dev)->ioaddr + (SSS_REG_##reg))
133 #define SSS_READ(dev, reg)              __raw_readl(SSS_REG(dev, reg))
134 #define SSS_WRITE(dev, reg, val)        __raw_writel((val), SSS_REG(dev, reg))
135 
136 #define SSS_AES_REG(dev, reg)           ((dev)->aes_ioaddr + SSS_REG_##reg)
137 #define SSS_AES_WRITE(dev, reg, val)    __raw_writel((val), \
138 						SSS_AES_REG(dev, reg))
139 
140 /* HW engine modes */
141 #define FLAGS_AES_DECRYPT               BIT(0)
142 #define FLAGS_AES_MODE_MASK             _SBF(1, 0x03)
143 #define FLAGS_AES_CBC                   _SBF(1, 0x01)
144 #define FLAGS_AES_CTR                   _SBF(1, 0x02)
145 
146 #define AES_KEY_LEN         16
147 #define CRYPTO_QUEUE_LEN    1
148 
149 /**
150  * struct samsung_aes_variant - platform specific SSS driver data
151  * @aes_offset: AES register offset from SSS module's base.
152  *
153  * Specifies platform specific configuration of SSS module.
154  * Note: A structure for driver specific platform data is used for future
155  * expansion of its usage.
156  */
157 struct samsung_aes_variant {
158 	unsigned int		    aes_offset;
159 };
160 
161 struct s5p_aes_reqctx {
162 	unsigned long mode;
163 };
164 
165 struct s5p_aes_ctx {
166 	struct s5p_aes_dev         *dev;
167 
168 	uint8_t                     aes_key[AES_MAX_KEY_SIZE];
169 	uint8_t                     nonce[CTR_RFC3686_NONCE_SIZE];
170 	int                         keylen;
171 };
172 
173 struct s5p_aes_dev {
174 	struct device              *dev;
175 	struct clk                 *clk;
176 	void __iomem               *ioaddr;
177 	void __iomem               *aes_ioaddr;
178 	int                         irq_fc;
179 
180 	struct ablkcipher_request  *req;
181 	struct s5p_aes_ctx         *ctx;
182 	struct scatterlist         *sg_src;
183 	struct scatterlist         *sg_dst;
184 
185 	/* In case of unaligned access: */
186 	struct scatterlist         *sg_src_cpy;
187 	struct scatterlist         *sg_dst_cpy;
188 
189 	struct tasklet_struct       tasklet;
190 	struct crypto_queue         queue;
191 	bool                        busy;
192 	spinlock_t                  lock;
193 
194 	struct samsung_aes_variant *variant;
195 };
196 
197 static struct s5p_aes_dev *s5p_dev;
198 
199 static const struct samsung_aes_variant s5p_aes_data = {
200 	.aes_offset	= 0x4000,
201 };
202 
203 static const struct samsung_aes_variant exynos_aes_data = {
204 	.aes_offset	= 0x200,
205 };
206 
207 static const struct of_device_id s5p_sss_dt_match[] = {
208 	{
209 		.compatible = "samsung,s5pv210-secss",
210 		.data = &s5p_aes_data,
211 	},
212 	{
213 		.compatible = "samsung,exynos4210-secss",
214 		.data = &exynos_aes_data,
215 	},
216 	{ },
217 };
218 MODULE_DEVICE_TABLE(of, s5p_sss_dt_match);
219 
220 static inline struct samsung_aes_variant *find_s5p_sss_version
221 				   (struct platform_device *pdev)
222 {
223 	if (IS_ENABLED(CONFIG_OF) && (pdev->dev.of_node)) {
224 		const struct of_device_id *match;
225 
226 		match = of_match_node(s5p_sss_dt_match,
227 					pdev->dev.of_node);
228 		return (struct samsung_aes_variant *)match->data;
229 	}
230 	return (struct samsung_aes_variant *)
231 			platform_get_device_id(pdev)->driver_data;
232 }
233 
234 static void s5p_set_dma_indata(struct s5p_aes_dev *dev, struct scatterlist *sg)
235 {
236 	SSS_WRITE(dev, FCBRDMAS, sg_dma_address(sg));
237 	SSS_WRITE(dev, FCBRDMAL, sg_dma_len(sg));
238 }
239 
240 static void s5p_set_dma_outdata(struct s5p_aes_dev *dev, struct scatterlist *sg)
241 {
242 	SSS_WRITE(dev, FCBTDMAS, sg_dma_address(sg));
243 	SSS_WRITE(dev, FCBTDMAL, sg_dma_len(sg));
244 }
245 
246 static void s5p_free_sg_cpy(struct s5p_aes_dev *dev, struct scatterlist **sg)
247 {
248 	int len;
249 
250 	if (!*sg)
251 		return;
252 
253 	len = ALIGN(dev->req->nbytes, AES_BLOCK_SIZE);
254 	free_pages((unsigned long)sg_virt(*sg), get_order(len));
255 
256 	kfree(*sg);
257 	*sg = NULL;
258 }
259 
260 static void s5p_sg_copy_buf(void *buf, struct scatterlist *sg,
261 			    unsigned int nbytes, int out)
262 {
263 	struct scatter_walk walk;
264 
265 	if (!nbytes)
266 		return;
267 
268 	scatterwalk_start(&walk, sg);
269 	scatterwalk_copychunks(buf, &walk, nbytes, out);
270 	scatterwalk_done(&walk, out, 0);
271 }
272 
273 static void s5p_aes_complete(struct s5p_aes_dev *dev, int err)
274 {
275 	if (dev->sg_dst_cpy) {
276 		dev_dbg(dev->dev,
277 			"Copying %d bytes of output data back to original place\n",
278 			dev->req->nbytes);
279 		s5p_sg_copy_buf(sg_virt(dev->sg_dst_cpy), dev->req->dst,
280 				dev->req->nbytes, 1);
281 	}
282 	s5p_free_sg_cpy(dev, &dev->sg_src_cpy);
283 	s5p_free_sg_cpy(dev, &dev->sg_dst_cpy);
284 
285 	/* holding a lock outside */
286 	dev->req->base.complete(&dev->req->base, err);
287 	dev->busy = false;
288 }
289 
290 static void s5p_unset_outdata(struct s5p_aes_dev *dev)
291 {
292 	dma_unmap_sg(dev->dev, dev->sg_dst, 1, DMA_FROM_DEVICE);
293 }
294 
295 static void s5p_unset_indata(struct s5p_aes_dev *dev)
296 {
297 	dma_unmap_sg(dev->dev, dev->sg_src, 1, DMA_TO_DEVICE);
298 }
299 
300 static int s5p_make_sg_cpy(struct s5p_aes_dev *dev, struct scatterlist *src,
301 			    struct scatterlist **dst)
302 {
303 	void *pages;
304 	int len;
305 
306 	*dst = kmalloc(sizeof(**dst), GFP_ATOMIC);
307 	if (!*dst)
308 		return -ENOMEM;
309 
310 	len = ALIGN(dev->req->nbytes, AES_BLOCK_SIZE);
311 	pages = (void *)__get_free_pages(GFP_ATOMIC, get_order(len));
312 	if (!pages) {
313 		kfree(*dst);
314 		*dst = NULL;
315 		return -ENOMEM;
316 	}
317 
318 	s5p_sg_copy_buf(pages, src, dev->req->nbytes, 0);
319 
320 	sg_init_table(*dst, 1);
321 	sg_set_buf(*dst, pages, len);
322 
323 	return 0;
324 }
325 
326 static int s5p_set_outdata(struct s5p_aes_dev *dev, struct scatterlist *sg)
327 {
328 	int err;
329 
330 	if (!sg->length) {
331 		err = -EINVAL;
332 		goto exit;
333 	}
334 
335 	err = dma_map_sg(dev->dev, sg, 1, DMA_FROM_DEVICE);
336 	if (!err) {
337 		err = -ENOMEM;
338 		goto exit;
339 	}
340 
341 	dev->sg_dst = sg;
342 	err = 0;
343 
344 exit:
345 	return err;
346 }
347 
348 static int s5p_set_indata(struct s5p_aes_dev *dev, struct scatterlist *sg)
349 {
350 	int err;
351 
352 	if (!sg->length) {
353 		err = -EINVAL;
354 		goto exit;
355 	}
356 
357 	err = dma_map_sg(dev->dev, sg, 1, DMA_TO_DEVICE);
358 	if (!err) {
359 		err = -ENOMEM;
360 		goto exit;
361 	}
362 
363 	dev->sg_src = sg;
364 	err = 0;
365 
366 exit:
367 	return err;
368 }
369 
370 /*
371  * Returns true if new transmitting (output) data is ready and its
372  * address+length have to be written to device (by calling
373  * s5p_set_dma_outdata()). False otherwise.
374  */
375 static bool s5p_aes_tx(struct s5p_aes_dev *dev)
376 {
377 	int err = 0;
378 	bool ret = false;
379 
380 	s5p_unset_outdata(dev);
381 
382 	if (!sg_is_last(dev->sg_dst)) {
383 		err = s5p_set_outdata(dev, sg_next(dev->sg_dst));
384 		if (err)
385 			s5p_aes_complete(dev, err);
386 		else
387 			ret = true;
388 	} else {
389 		s5p_aes_complete(dev, err);
390 
391 		dev->busy = true;
392 		tasklet_schedule(&dev->tasklet);
393 	}
394 
395 	return ret;
396 }
397 
398 /*
399  * Returns true if new receiving (input) data is ready and its
400  * address+length have to be written to device (by calling
401  * s5p_set_dma_indata()). False otherwise.
402  */
403 static bool s5p_aes_rx(struct s5p_aes_dev *dev)
404 {
405 	int err;
406 	bool ret = false;
407 
408 	s5p_unset_indata(dev);
409 
410 	if (!sg_is_last(dev->sg_src)) {
411 		err = s5p_set_indata(dev, sg_next(dev->sg_src));
412 		if (err)
413 			s5p_aes_complete(dev, err);
414 		else
415 			ret = true;
416 	}
417 
418 	return ret;
419 }
420 
421 static irqreturn_t s5p_aes_interrupt(int irq, void *dev_id)
422 {
423 	struct platform_device *pdev = dev_id;
424 	struct s5p_aes_dev     *dev  = platform_get_drvdata(pdev);
425 	uint32_t                status;
426 	unsigned long           flags;
427 	bool			set_dma_tx = false;
428 	bool			set_dma_rx = false;
429 
430 	spin_lock_irqsave(&dev->lock, flags);
431 
432 	status = SSS_READ(dev, FCINTSTAT);
433 	if (status & SSS_FCINTSTAT_BRDMAINT)
434 		set_dma_rx = s5p_aes_rx(dev);
435 	if (status & SSS_FCINTSTAT_BTDMAINT)
436 		set_dma_tx = s5p_aes_tx(dev);
437 
438 	SSS_WRITE(dev, FCINTPEND, status);
439 
440 	/*
441 	 * Writing length of DMA block (either receiving or transmitting)
442 	 * will start the operation immediately, so this should be done
443 	 * at the end (even after clearing pending interrupts to not miss the
444 	 * interrupt).
445 	 */
446 	if (set_dma_tx)
447 		s5p_set_dma_outdata(dev, dev->sg_dst);
448 	if (set_dma_rx)
449 		s5p_set_dma_indata(dev, dev->sg_src);
450 
451 	spin_unlock_irqrestore(&dev->lock, flags);
452 
453 	return IRQ_HANDLED;
454 }
455 
456 static void s5p_set_aes(struct s5p_aes_dev *dev,
457 			uint8_t *key, uint8_t *iv, unsigned int keylen)
458 {
459 	void __iomem *keystart;
460 
461 	if (iv)
462 		memcpy_toio(dev->aes_ioaddr + SSS_REG_AES_IV_DATA(0), iv, 0x10);
463 
464 	if (keylen == AES_KEYSIZE_256)
465 		keystart = dev->aes_ioaddr + SSS_REG_AES_KEY_DATA(0);
466 	else if (keylen == AES_KEYSIZE_192)
467 		keystart = dev->aes_ioaddr + SSS_REG_AES_KEY_DATA(2);
468 	else
469 		keystart = dev->aes_ioaddr + SSS_REG_AES_KEY_DATA(4);
470 
471 	memcpy_toio(keystart, key, keylen);
472 }
473 
474 static bool s5p_is_sg_aligned(struct scatterlist *sg)
475 {
476 	while (sg) {
477 		if (!IS_ALIGNED(sg->length, AES_BLOCK_SIZE))
478 			return false;
479 		sg = sg_next(sg);
480 	}
481 
482 	return true;
483 }
484 
485 static int s5p_set_indata_start(struct s5p_aes_dev *dev,
486 				struct ablkcipher_request *req)
487 {
488 	struct scatterlist *sg;
489 	int err;
490 
491 	dev->sg_src_cpy = NULL;
492 	sg = req->src;
493 	if (!s5p_is_sg_aligned(sg)) {
494 		dev_dbg(dev->dev,
495 			"At least one unaligned source scatter list, making a copy\n");
496 		err = s5p_make_sg_cpy(dev, sg, &dev->sg_src_cpy);
497 		if (err)
498 			return err;
499 
500 		sg = dev->sg_src_cpy;
501 	}
502 
503 	err = s5p_set_indata(dev, sg);
504 	if (err) {
505 		s5p_free_sg_cpy(dev, &dev->sg_src_cpy);
506 		return err;
507 	}
508 
509 	return 0;
510 }
511 
512 static int s5p_set_outdata_start(struct s5p_aes_dev *dev,
513 				struct ablkcipher_request *req)
514 {
515 	struct scatterlist *sg;
516 	int err;
517 
518 	dev->sg_dst_cpy = NULL;
519 	sg = req->dst;
520 	if (!s5p_is_sg_aligned(sg)) {
521 		dev_dbg(dev->dev,
522 			"At least one unaligned dest scatter list, making a copy\n");
523 		err = s5p_make_sg_cpy(dev, sg, &dev->sg_dst_cpy);
524 		if (err)
525 			return err;
526 
527 		sg = dev->sg_dst_cpy;
528 	}
529 
530 	err = s5p_set_outdata(dev, sg);
531 	if (err) {
532 		s5p_free_sg_cpy(dev, &dev->sg_dst_cpy);
533 		return err;
534 	}
535 
536 	return 0;
537 }
538 
539 static void s5p_aes_crypt_start(struct s5p_aes_dev *dev, unsigned long mode)
540 {
541 	struct ablkcipher_request  *req = dev->req;
542 	uint32_t                    aes_control;
543 	int                         err;
544 	unsigned long               flags;
545 
546 	aes_control = SSS_AES_KEY_CHANGE_MODE;
547 	if (mode & FLAGS_AES_DECRYPT)
548 		aes_control |= SSS_AES_MODE_DECRYPT;
549 
550 	if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CBC)
551 		aes_control |= SSS_AES_CHAIN_MODE_CBC;
552 	else if ((mode & FLAGS_AES_MODE_MASK) == FLAGS_AES_CTR)
553 		aes_control |= SSS_AES_CHAIN_MODE_CTR;
554 
555 	if (dev->ctx->keylen == AES_KEYSIZE_192)
556 		aes_control |= SSS_AES_KEY_SIZE_192;
557 	else if (dev->ctx->keylen == AES_KEYSIZE_256)
558 		aes_control |= SSS_AES_KEY_SIZE_256;
559 
560 	aes_control |= SSS_AES_FIFO_MODE;
561 
562 	/* as a variant it is possible to use byte swapping on DMA side */
563 	aes_control |= SSS_AES_BYTESWAP_DI
564 		    |  SSS_AES_BYTESWAP_DO
565 		    |  SSS_AES_BYTESWAP_IV
566 		    |  SSS_AES_BYTESWAP_KEY
567 		    |  SSS_AES_BYTESWAP_CNT;
568 
569 	spin_lock_irqsave(&dev->lock, flags);
570 
571 	SSS_WRITE(dev, FCINTENCLR,
572 		  SSS_FCINTENCLR_BTDMAINTENCLR | SSS_FCINTENCLR_BRDMAINTENCLR);
573 	SSS_WRITE(dev, FCFIFOCTRL, 0x00);
574 
575 	err = s5p_set_indata_start(dev, req);
576 	if (err)
577 		goto indata_error;
578 
579 	err = s5p_set_outdata_start(dev, req);
580 	if (err)
581 		goto outdata_error;
582 
583 	SSS_AES_WRITE(dev, AES_CONTROL, aes_control);
584 	s5p_set_aes(dev, dev->ctx->aes_key, req->info, dev->ctx->keylen);
585 
586 	s5p_set_dma_indata(dev,  dev->sg_src);
587 	s5p_set_dma_outdata(dev, dev->sg_dst);
588 
589 	SSS_WRITE(dev, FCINTENSET,
590 		  SSS_FCINTENSET_BTDMAINTENSET | SSS_FCINTENSET_BRDMAINTENSET);
591 
592 	spin_unlock_irqrestore(&dev->lock, flags);
593 
594 	return;
595 
596 outdata_error:
597 	s5p_unset_indata(dev);
598 
599 indata_error:
600 	s5p_aes_complete(dev, err);
601 	spin_unlock_irqrestore(&dev->lock, flags);
602 }
603 
604 static void s5p_tasklet_cb(unsigned long data)
605 {
606 	struct s5p_aes_dev *dev = (struct s5p_aes_dev *)data;
607 	struct crypto_async_request *async_req, *backlog;
608 	struct s5p_aes_reqctx *reqctx;
609 	unsigned long flags;
610 
611 	spin_lock_irqsave(&dev->lock, flags);
612 	backlog   = crypto_get_backlog(&dev->queue);
613 	async_req = crypto_dequeue_request(&dev->queue);
614 
615 	if (!async_req) {
616 		dev->busy = false;
617 		spin_unlock_irqrestore(&dev->lock, flags);
618 		return;
619 	}
620 	spin_unlock_irqrestore(&dev->lock, flags);
621 
622 	if (backlog)
623 		backlog->complete(backlog, -EINPROGRESS);
624 
625 	dev->req = ablkcipher_request_cast(async_req);
626 	dev->ctx = crypto_tfm_ctx(dev->req->base.tfm);
627 	reqctx   = ablkcipher_request_ctx(dev->req);
628 
629 	s5p_aes_crypt_start(dev, reqctx->mode);
630 }
631 
632 static int s5p_aes_handle_req(struct s5p_aes_dev *dev,
633 			      struct ablkcipher_request *req)
634 {
635 	unsigned long flags;
636 	int err;
637 
638 	spin_lock_irqsave(&dev->lock, flags);
639 	err = ablkcipher_enqueue_request(&dev->queue, req);
640 	if (dev->busy) {
641 		spin_unlock_irqrestore(&dev->lock, flags);
642 		goto exit;
643 	}
644 	dev->busy = true;
645 
646 	spin_unlock_irqrestore(&dev->lock, flags);
647 
648 	tasklet_schedule(&dev->tasklet);
649 
650 exit:
651 	return err;
652 }
653 
654 static int s5p_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
655 {
656 	struct crypto_ablkcipher   *tfm    = crypto_ablkcipher_reqtfm(req);
657 	struct s5p_aes_ctx         *ctx    = crypto_ablkcipher_ctx(tfm);
658 	struct s5p_aes_reqctx      *reqctx = ablkcipher_request_ctx(req);
659 	struct s5p_aes_dev         *dev    = ctx->dev;
660 
661 	if (!IS_ALIGNED(req->nbytes, AES_BLOCK_SIZE)) {
662 		dev_err(dev->dev, "request size is not exact amount of AES blocks\n");
663 		return -EINVAL;
664 	}
665 
666 	reqctx->mode = mode;
667 
668 	return s5p_aes_handle_req(dev, req);
669 }
670 
671 static int s5p_aes_setkey(struct crypto_ablkcipher *cipher,
672 			  const uint8_t *key, unsigned int keylen)
673 {
674 	struct crypto_tfm  *tfm = crypto_ablkcipher_tfm(cipher);
675 	struct s5p_aes_ctx *ctx = crypto_tfm_ctx(tfm);
676 
677 	if (keylen != AES_KEYSIZE_128 &&
678 	    keylen != AES_KEYSIZE_192 &&
679 	    keylen != AES_KEYSIZE_256)
680 		return -EINVAL;
681 
682 	memcpy(ctx->aes_key, key, keylen);
683 	ctx->keylen = keylen;
684 
685 	return 0;
686 }
687 
688 static int s5p_aes_ecb_encrypt(struct ablkcipher_request *req)
689 {
690 	return s5p_aes_crypt(req, 0);
691 }
692 
693 static int s5p_aes_ecb_decrypt(struct ablkcipher_request *req)
694 {
695 	return s5p_aes_crypt(req, FLAGS_AES_DECRYPT);
696 }
697 
698 static int s5p_aes_cbc_encrypt(struct ablkcipher_request *req)
699 {
700 	return s5p_aes_crypt(req, FLAGS_AES_CBC);
701 }
702 
703 static int s5p_aes_cbc_decrypt(struct ablkcipher_request *req)
704 {
705 	return s5p_aes_crypt(req, FLAGS_AES_DECRYPT | FLAGS_AES_CBC);
706 }
707 
708 static int s5p_aes_cra_init(struct crypto_tfm *tfm)
709 {
710 	struct s5p_aes_ctx *ctx = crypto_tfm_ctx(tfm);
711 
712 	ctx->dev = s5p_dev;
713 	tfm->crt_ablkcipher.reqsize = sizeof(struct s5p_aes_reqctx);
714 
715 	return 0;
716 }
717 
718 static struct crypto_alg algs[] = {
719 	{
720 		.cra_name		= "ecb(aes)",
721 		.cra_driver_name	= "ecb-aes-s5p",
722 		.cra_priority		= 100,
723 		.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
724 					  CRYPTO_ALG_ASYNC |
725 					  CRYPTO_ALG_KERN_DRIVER_ONLY,
726 		.cra_blocksize		= AES_BLOCK_SIZE,
727 		.cra_ctxsize		= sizeof(struct s5p_aes_ctx),
728 		.cra_alignmask		= 0x0f,
729 		.cra_type		= &crypto_ablkcipher_type,
730 		.cra_module		= THIS_MODULE,
731 		.cra_init		= s5p_aes_cra_init,
732 		.cra_u.ablkcipher = {
733 			.min_keysize	= AES_MIN_KEY_SIZE,
734 			.max_keysize	= AES_MAX_KEY_SIZE,
735 			.setkey		= s5p_aes_setkey,
736 			.encrypt	= s5p_aes_ecb_encrypt,
737 			.decrypt	= s5p_aes_ecb_decrypt,
738 		}
739 	},
740 	{
741 		.cra_name		= "cbc(aes)",
742 		.cra_driver_name	= "cbc-aes-s5p",
743 		.cra_priority		= 100,
744 		.cra_flags		= CRYPTO_ALG_TYPE_ABLKCIPHER |
745 					  CRYPTO_ALG_ASYNC |
746 					  CRYPTO_ALG_KERN_DRIVER_ONLY,
747 		.cra_blocksize		= AES_BLOCK_SIZE,
748 		.cra_ctxsize		= sizeof(struct s5p_aes_ctx),
749 		.cra_alignmask		= 0x0f,
750 		.cra_type		= &crypto_ablkcipher_type,
751 		.cra_module		= THIS_MODULE,
752 		.cra_init		= s5p_aes_cra_init,
753 		.cra_u.ablkcipher = {
754 			.min_keysize	= AES_MIN_KEY_SIZE,
755 			.max_keysize	= AES_MAX_KEY_SIZE,
756 			.ivsize		= AES_BLOCK_SIZE,
757 			.setkey		= s5p_aes_setkey,
758 			.encrypt	= s5p_aes_cbc_encrypt,
759 			.decrypt	= s5p_aes_cbc_decrypt,
760 		}
761 	},
762 };
763 
764 static int s5p_aes_probe(struct platform_device *pdev)
765 {
766 	int                 i, j, err = -ENODEV;
767 	struct s5p_aes_dev *pdata;
768 	struct device      *dev = &pdev->dev;
769 	struct resource    *res;
770 	struct samsung_aes_variant *variant;
771 
772 	if (s5p_dev)
773 		return -EEXIST;
774 
775 	pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
776 	if (!pdata)
777 		return -ENOMEM;
778 
779 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
780 	pdata->ioaddr = devm_ioremap_resource(&pdev->dev, res);
781 	if (IS_ERR(pdata->ioaddr))
782 		return PTR_ERR(pdata->ioaddr);
783 
784 	variant = find_s5p_sss_version(pdev);
785 
786 	pdata->clk = devm_clk_get(dev, "secss");
787 	if (IS_ERR(pdata->clk)) {
788 		dev_err(dev, "failed to find secss clock source\n");
789 		return -ENOENT;
790 	}
791 
792 	err = clk_prepare_enable(pdata->clk);
793 	if (err < 0) {
794 		dev_err(dev, "Enabling SSS clk failed, err %d\n", err);
795 		return err;
796 	}
797 
798 	spin_lock_init(&pdata->lock);
799 
800 	pdata->aes_ioaddr = pdata->ioaddr + variant->aes_offset;
801 
802 	pdata->irq_fc = platform_get_irq(pdev, 0);
803 	if (pdata->irq_fc < 0) {
804 		err = pdata->irq_fc;
805 		dev_warn(dev, "feed control interrupt is not available.\n");
806 		goto err_irq;
807 	}
808 	err = devm_request_irq(dev, pdata->irq_fc, s5p_aes_interrupt,
809 			       IRQF_SHARED, pdev->name, pdev);
810 	if (err < 0) {
811 		dev_warn(dev, "feed control interrupt is not available.\n");
812 		goto err_irq;
813 	}
814 
815 	pdata->busy = false;
816 	pdata->variant = variant;
817 	pdata->dev = dev;
818 	platform_set_drvdata(pdev, pdata);
819 	s5p_dev = pdata;
820 
821 	tasklet_init(&pdata->tasklet, s5p_tasklet_cb, (unsigned long)pdata);
822 	crypto_init_queue(&pdata->queue, CRYPTO_QUEUE_LEN);
823 
824 	for (i = 0; i < ARRAY_SIZE(algs); i++) {
825 		err = crypto_register_alg(&algs[i]);
826 		if (err)
827 			goto err_algs;
828 	}
829 
830 	dev_info(dev, "s5p-sss driver registered\n");
831 
832 	return 0;
833 
834 err_algs:
835 	dev_err(dev, "can't register '%s': %d\n", algs[i].cra_name, err);
836 
837 	for (j = 0; j < i; j++)
838 		crypto_unregister_alg(&algs[j]);
839 
840 	tasklet_kill(&pdata->tasklet);
841 
842 err_irq:
843 	clk_disable_unprepare(pdata->clk);
844 
845 	s5p_dev = NULL;
846 
847 	return err;
848 }
849 
850 static int s5p_aes_remove(struct platform_device *pdev)
851 {
852 	struct s5p_aes_dev *pdata = platform_get_drvdata(pdev);
853 	int i;
854 
855 	if (!pdata)
856 		return -ENODEV;
857 
858 	for (i = 0; i < ARRAY_SIZE(algs); i++)
859 		crypto_unregister_alg(&algs[i]);
860 
861 	tasklet_kill(&pdata->tasklet);
862 
863 	clk_disable_unprepare(pdata->clk);
864 
865 	s5p_dev = NULL;
866 
867 	return 0;
868 }
869 
870 static struct platform_driver s5p_aes_crypto = {
871 	.probe	= s5p_aes_probe,
872 	.remove	= s5p_aes_remove,
873 	.driver	= {
874 		.name	= "s5p-secss",
875 		.of_match_table = s5p_sss_dt_match,
876 	},
877 };
878 
879 module_platform_driver(s5p_aes_crypto);
880 
881 MODULE_DESCRIPTION("S5PV210 AES hw acceleration support.");
882 MODULE_LICENSE("GPL v2");
883 MODULE_AUTHOR("Vladimir Zapolskiy <vzapolskiy@gmail.com>");
884