blob: c3dc1c04a5df6f39966b3ca4a9c9874c001035ec [file] [log] [blame]
Javier Martin5de88752013-03-01 12:37:53 +01001/*
2 * Cryptographic API.
3 *
4 * Support for SAHARA cryptographic accelerator.
5 *
6 * Copyright (c) 2013 Vista Silicon S.L.
7 * Author: Javier Martin <javier.martin@vista-silicon.com>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License version 2 as published
11 * by the Free Software Foundation.
12 *
13 * Based on omap-aes.c and tegra-aes.c
14 */
15
16#include <crypto/algapi.h>
17#include <crypto/aes.h>
18
19#include <linux/clk.h>
20#include <linux/crypto.h>
21#include <linux/interrupt.h>
22#include <linux/io.h>
23#include <linux/irq.h>
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/of.h>
27#include <linux/platform_device.h>
28
29#define SAHARA_NAME "sahara"
30#define SAHARA_VERSION_3 3
31#define SAHARA_TIMEOUT_MS 1000
32#define SAHARA_MAX_HW_DESC 2
33#define SAHARA_MAX_HW_LINK 20
34
35#define FLAGS_MODE_MASK 0x000f
36#define FLAGS_ENCRYPT BIT(0)
37#define FLAGS_CBC BIT(1)
38#define FLAGS_NEW_KEY BIT(3)
39#define FLAGS_BUSY 4
40
41#define SAHARA_HDR_BASE 0x00800000
42#define SAHARA_HDR_SKHA_ALG_AES 0
43#define SAHARA_HDR_SKHA_OP_ENC (1 << 2)
44#define SAHARA_HDR_SKHA_MODE_ECB (0 << 3)
45#define SAHARA_HDR_SKHA_MODE_CBC (1 << 3)
46#define SAHARA_HDR_FORM_DATA (5 << 16)
47#define SAHARA_HDR_FORM_KEY (8 << 16)
48#define SAHARA_HDR_LLO (1 << 24)
49#define SAHARA_HDR_CHA_SKHA (1 << 28)
50#define SAHARA_HDR_CHA_MDHA (2 << 28)
51#define SAHARA_HDR_PARITY_BIT (1 << 31)
52
53/* SAHARA can only process one request at a time */
54#define SAHARA_QUEUE_LENGTH 1
55
56#define SAHARA_REG_VERSION 0x00
57#define SAHARA_REG_DAR 0x04
58#define SAHARA_REG_CONTROL 0x08
59#define SAHARA_CONTROL_SET_THROTTLE(x) (((x) & 0xff) << 24)
60#define SAHARA_CONTROL_SET_MAXBURST(x) (((x) & 0xff) << 16)
61#define SAHARA_CONTROL_RNG_AUTORSD (1 << 7)
62#define SAHARA_CONTROL_ENABLE_INT (1 << 4)
63#define SAHARA_REG_CMD 0x0C
64#define SAHARA_CMD_RESET (1 << 0)
65#define SAHARA_CMD_CLEAR_INT (1 << 8)
66#define SAHARA_CMD_CLEAR_ERR (1 << 9)
67#define SAHARA_CMD_SINGLE_STEP (1 << 10)
68#define SAHARA_CMD_MODE_BATCH (1 << 16)
69#define SAHARA_CMD_MODE_DEBUG (1 << 18)
70#define SAHARA_REG_STATUS 0x10
71#define SAHARA_STATUS_GET_STATE(x) ((x) & 0x7)
72#define SAHARA_STATE_IDLE 0
73#define SAHARA_STATE_BUSY 1
74#define SAHARA_STATE_ERR 2
75#define SAHARA_STATE_FAULT 3
76#define SAHARA_STATE_COMPLETE 4
77#define SAHARA_STATE_COMP_FLAG (1 << 2)
78#define SAHARA_STATUS_DAR_FULL (1 << 3)
79#define SAHARA_STATUS_ERROR (1 << 4)
80#define SAHARA_STATUS_SECURE (1 << 5)
81#define SAHARA_STATUS_FAIL (1 << 6)
82#define SAHARA_STATUS_INIT (1 << 7)
83#define SAHARA_STATUS_RNG_RESEED (1 << 8)
84#define SAHARA_STATUS_ACTIVE_RNG (1 << 9)
85#define SAHARA_STATUS_ACTIVE_MDHA (1 << 10)
86#define SAHARA_STATUS_ACTIVE_SKHA (1 << 11)
87#define SAHARA_STATUS_MODE_BATCH (1 << 16)
88#define SAHARA_STATUS_MODE_DEDICATED (1 << 17)
89#define SAHARA_STATUS_MODE_DEBUG (1 << 18)
90#define SAHARA_STATUS_GET_ISTATE(x) (((x) >> 24) & 0xff)
91#define SAHARA_REG_ERRSTATUS 0x14
92#define SAHARA_ERRSTATUS_GET_SOURCE(x) ((x) & 0xf)
93#define SAHARA_ERRSOURCE_CHA 14
94#define SAHARA_ERRSOURCE_DMA 15
95#define SAHARA_ERRSTATUS_DMA_DIR (1 << 8)
96#define SAHARA_ERRSTATUS_GET_DMASZ(x)(((x) >> 9) & 0x3)
97#define SAHARA_ERRSTATUS_GET_DMASRC(x) (((x) >> 13) & 0x7)
98#define SAHARA_ERRSTATUS_GET_CHASRC(x) (((x) >> 16) & 0xfff)
99#define SAHARA_ERRSTATUS_GET_CHAERR(x) (((x) >> 28) & 0x3)
100#define SAHARA_REG_FADDR 0x18
101#define SAHARA_REG_CDAR 0x1C
102#define SAHARA_REG_IDAR 0x20
103
104struct sahara_hw_desc {
105 u32 hdr;
106 u32 len1;
107 dma_addr_t p1;
108 u32 len2;
109 dma_addr_t p2;
110 dma_addr_t next;
111};
112
113struct sahara_hw_link {
114 u32 len;
115 dma_addr_t p;
116 dma_addr_t next;
117};
118
119struct sahara_ctx {
120 struct sahara_dev *dev;
121 unsigned long flags;
122 int keylen;
123 u8 key[AES_KEYSIZE_128];
124 struct crypto_ablkcipher *fallback;
125};
126
127struct sahara_aes_reqctx {
128 unsigned long mode;
129};
130
131struct sahara_dev {
132 struct device *device;
133 void __iomem *regs_base;
134 struct clk *clk_ipg;
135 struct clk *clk_ahb;
136
137 struct sahara_ctx *ctx;
138 spinlock_t lock;
139 struct crypto_queue queue;
140 unsigned long flags;
141
142 struct tasklet_struct done_task;
143 struct tasklet_struct queue_task;
144
145 struct sahara_hw_desc *hw_desc[SAHARA_MAX_HW_DESC];
146 dma_addr_t hw_phys_desc[SAHARA_MAX_HW_DESC];
147
148 u8 *key_base;
149 dma_addr_t key_phys_base;
150
151 u8 *iv_base;
152 dma_addr_t iv_phys_base;
153
154 struct sahara_hw_link *hw_link[SAHARA_MAX_HW_LINK];
155 dma_addr_t hw_phys_link[SAHARA_MAX_HW_LINK];
156
157 struct ablkcipher_request *req;
158 size_t total;
159 struct scatterlist *in_sg;
160 unsigned int nb_in_sg;
161 struct scatterlist *out_sg;
162 unsigned int nb_out_sg;
163
164 u32 error;
165 struct timer_list watchdog;
166};
167
168static struct sahara_dev *dev_ptr;
169
170static inline void sahara_write(struct sahara_dev *dev, u32 data, u32 reg)
171{
172 writel(data, dev->regs_base + reg);
173}
174
175static inline unsigned int sahara_read(struct sahara_dev *dev, u32 reg)
176{
177 return readl(dev->regs_base + reg);
178}
179
180static u32 sahara_aes_key_hdr(struct sahara_dev *dev)
181{
182 u32 hdr = SAHARA_HDR_BASE | SAHARA_HDR_SKHA_ALG_AES |
183 SAHARA_HDR_FORM_KEY | SAHARA_HDR_LLO |
184 SAHARA_HDR_CHA_SKHA | SAHARA_HDR_PARITY_BIT;
185
186 if (dev->flags & FLAGS_CBC) {
187 hdr |= SAHARA_HDR_SKHA_MODE_CBC;
188 hdr ^= SAHARA_HDR_PARITY_BIT;
189 }
190
191 if (dev->flags & FLAGS_ENCRYPT) {
192 hdr |= SAHARA_HDR_SKHA_OP_ENC;
193 hdr ^= SAHARA_HDR_PARITY_BIT;
194 }
195
196 return hdr;
197}
198
199static u32 sahara_aes_data_link_hdr(struct sahara_dev *dev)
200{
201 return SAHARA_HDR_BASE | SAHARA_HDR_FORM_DATA |
202 SAHARA_HDR_CHA_SKHA | SAHARA_HDR_PARITY_BIT;
203}
204
205static int sahara_sg_length(struct scatterlist *sg,
206 unsigned int total)
207{
208 int sg_nb;
209 unsigned int len;
210 struct scatterlist *sg_list;
211
212 sg_nb = 0;
213 sg_list = sg;
214
215 while (total) {
216 len = min(sg_list->length, total);
217
218 sg_nb++;
219 total -= len;
220
221 sg_list = sg_next(sg_list);
222 if (!sg_list)
223 total = 0;
224 }
225
226 return sg_nb;
227}
228
229static char *sahara_err_src[16] = {
230 "No error",
231 "Header error",
232 "Descriptor length error",
233 "Descriptor length or pointer error",
234 "Link length error",
235 "Link pointer error",
236 "Input buffer error",
237 "Output buffer error",
238 "Output buffer starvation",
239 "Internal state fault",
240 "General descriptor problem",
241 "Reserved",
242 "Descriptor address error",
243 "Link address error",
244 "CHA error",
245 "DMA error"
246};
247
248static char *sahara_err_dmasize[4] = {
249 "Byte transfer",
250 "Half-word transfer",
251 "Word transfer",
252 "Reserved"
253};
254
255static char *sahara_err_dmasrc[8] = {
256 "No error",
257 "AHB bus error",
258 "Internal IP bus error",
259 "Parity error",
260 "DMA crosses 256 byte boundary",
261 "DMA is busy",
262 "Reserved",
263 "DMA HW error"
264};
265
266static char *sahara_cha_errsrc[12] = {
267 "Input buffer non-empty",
268 "Illegal address",
269 "Illegal mode",
270 "Illegal data size",
271 "Illegal key size",
272 "Write during processing",
273 "CTX read during processing",
274 "HW error",
275 "Input buffer disabled/underflow",
276 "Output buffer disabled/overflow",
277 "DES key parity error",
278 "Reserved"
279};
280
281static char *sahara_cha_err[4] = { "No error", "SKHA", "MDHA", "RNG" };
282
283static void sahara_decode_error(struct sahara_dev *dev, unsigned int error)
284{
285 u8 source = SAHARA_ERRSTATUS_GET_SOURCE(error);
286 u16 chasrc = ffs(SAHARA_ERRSTATUS_GET_CHASRC(error));
287
288 dev_err(dev->device, "%s: Error Register = 0x%08x\n", __func__, error);
289
290 dev_err(dev->device, " - %s.\n", sahara_err_src[source]);
291
292 if (source == SAHARA_ERRSOURCE_DMA) {
293 if (error & SAHARA_ERRSTATUS_DMA_DIR)
294 dev_err(dev->device, " * DMA read.\n");
295 else
296 dev_err(dev->device, " * DMA write.\n");
297
298 dev_err(dev->device, " * %s.\n",
299 sahara_err_dmasize[SAHARA_ERRSTATUS_GET_DMASZ(error)]);
300 dev_err(dev->device, " * %s.\n",
301 sahara_err_dmasrc[SAHARA_ERRSTATUS_GET_DMASRC(error)]);
302 } else if (source == SAHARA_ERRSOURCE_CHA) {
303 dev_err(dev->device, " * %s.\n",
304 sahara_cha_errsrc[chasrc]);
305 dev_err(dev->device, " * %s.\n",
306 sahara_cha_err[SAHARA_ERRSTATUS_GET_CHAERR(error)]);
307 }
308 dev_err(dev->device, "\n");
309}
310
311static char *sahara_state[4] = { "Idle", "Busy", "Error", "HW Fault" };
312
313static void sahara_decode_status(struct sahara_dev *dev, unsigned int status)
314{
315 u8 state;
316
317 if (!IS_ENABLED(DEBUG))
318 return;
319
320 state = SAHARA_STATUS_GET_STATE(status);
321
322 dev_dbg(dev->device, "%s: Status Register = 0x%08x\n",
323 __func__, status);
324
325 dev_dbg(dev->device, " - State = %d:\n", state);
326 if (state & SAHARA_STATE_COMP_FLAG)
327 dev_dbg(dev->device, " * Descriptor completed. IRQ pending.\n");
328
329 dev_dbg(dev->device, " * %s.\n",
330 sahara_state[state & ~SAHARA_STATE_COMP_FLAG]);
331
332 if (status & SAHARA_STATUS_DAR_FULL)
333 dev_dbg(dev->device, " - DAR Full.\n");
334 if (status & SAHARA_STATUS_ERROR)
335 dev_dbg(dev->device, " - Error.\n");
336 if (status & SAHARA_STATUS_SECURE)
337 dev_dbg(dev->device, " - Secure.\n");
338 if (status & SAHARA_STATUS_FAIL)
339 dev_dbg(dev->device, " - Fail.\n");
340 if (status & SAHARA_STATUS_RNG_RESEED)
341 dev_dbg(dev->device, " - RNG Reseed Request.\n");
342 if (status & SAHARA_STATUS_ACTIVE_RNG)
343 dev_dbg(dev->device, " - RNG Active.\n");
344 if (status & SAHARA_STATUS_ACTIVE_MDHA)
345 dev_dbg(dev->device, " - MDHA Active.\n");
346 if (status & SAHARA_STATUS_ACTIVE_SKHA)
347 dev_dbg(dev->device, " - SKHA Active.\n");
348
349 if (status & SAHARA_STATUS_MODE_BATCH)
350 dev_dbg(dev->device, " - Batch Mode.\n");
351 else if (status & SAHARA_STATUS_MODE_DEDICATED)
352 dev_dbg(dev->device, " - Decidated Mode.\n");
353 else if (status & SAHARA_STATUS_MODE_DEBUG)
354 dev_dbg(dev->device, " - Debug Mode.\n");
355
356 dev_dbg(dev->device, " - Internal state = 0x%02x\n",
357 SAHARA_STATUS_GET_ISTATE(status));
358
359 dev_dbg(dev->device, "Current DAR: 0x%08x\n",
360 sahara_read(dev, SAHARA_REG_CDAR));
361 dev_dbg(dev->device, "Initial DAR: 0x%08x\n\n",
362 sahara_read(dev, SAHARA_REG_IDAR));
363}
364
365static void sahara_dump_descriptors(struct sahara_dev *dev)
366{
367 int i;
368
369 if (!IS_ENABLED(DEBUG))
370 return;
371
372 for (i = 0; i < SAHARA_MAX_HW_DESC; i++) {
373 dev_dbg(dev->device, "Descriptor (%d) (0x%08x):\n",
374 i, dev->hw_phys_desc[i]);
375 dev_dbg(dev->device, "\thdr = 0x%08x\n", dev->hw_desc[i]->hdr);
376 dev_dbg(dev->device, "\tlen1 = %u\n", dev->hw_desc[i]->len1);
377 dev_dbg(dev->device, "\tp1 = 0x%08x\n", dev->hw_desc[i]->p1);
378 dev_dbg(dev->device, "\tlen2 = %u\n", dev->hw_desc[i]->len2);
379 dev_dbg(dev->device, "\tp2 = 0x%08x\n", dev->hw_desc[i]->p2);
380 dev_dbg(dev->device, "\tnext = 0x%08x\n",
381 dev->hw_desc[i]->next);
382 }
383 dev_dbg(dev->device, "\n");
384}
385
386static void sahara_dump_links(struct sahara_dev *dev)
387{
388 int i;
389
390 if (!IS_ENABLED(DEBUG))
391 return;
392
393 for (i = 0; i < SAHARA_MAX_HW_LINK; i++) {
394 dev_dbg(dev->device, "Link (%d) (0x%08x):\n",
395 i, dev->hw_phys_link[i]);
396 dev_dbg(dev->device, "\tlen = %u\n", dev->hw_link[i]->len);
397 dev_dbg(dev->device, "\tp = 0x%08x\n", dev->hw_link[i]->p);
398 dev_dbg(dev->device, "\tnext = 0x%08x\n",
399 dev->hw_link[i]->next);
400 }
401 dev_dbg(dev->device, "\n");
402}
403
404static void sahara_aes_done_task(unsigned long data)
405{
406 struct sahara_dev *dev = (struct sahara_dev *)data;
407
408 dma_unmap_sg(dev->device, dev->out_sg, dev->nb_out_sg,
409 DMA_TO_DEVICE);
410 dma_unmap_sg(dev->device, dev->in_sg, dev->nb_in_sg,
411 DMA_FROM_DEVICE);
412
413 spin_lock(&dev->lock);
414 clear_bit(FLAGS_BUSY, &dev->flags);
415 spin_unlock(&dev->lock);
416
417 dev->req->base.complete(&dev->req->base, dev->error);
418}
419
420void sahara_watchdog(unsigned long data)
421{
422 struct sahara_dev *dev = (struct sahara_dev *)data;
423 unsigned int err = sahara_read(dev, SAHARA_REG_ERRSTATUS);
424 unsigned int stat = sahara_read(dev, SAHARA_REG_STATUS);
425
426 sahara_decode_status(dev, stat);
427 sahara_decode_error(dev, err);
428 dev->error = -ETIMEDOUT;
429 sahara_aes_done_task(data);
430}
431
432static int sahara_hw_descriptor_create(struct sahara_dev *dev)
433{
434 struct sahara_ctx *ctx = dev->ctx;
435 struct scatterlist *sg;
436 int ret;
437 int i, j;
438
439 /* Copy new key if necessary */
440 if (ctx->flags & FLAGS_NEW_KEY) {
441 memcpy(dev->key_base, ctx->key, ctx->keylen);
442 ctx->flags &= ~FLAGS_NEW_KEY;
443
444 if (dev->flags & FLAGS_CBC) {
445 dev->hw_desc[0]->len1 = AES_BLOCK_SIZE;
446 dev->hw_desc[0]->p1 = dev->iv_phys_base;
447 } else {
448 dev->hw_desc[0]->len1 = 0;
449 dev->hw_desc[0]->p1 = 0;
450 }
451 dev->hw_desc[0]->len2 = ctx->keylen;
452 dev->hw_desc[0]->p2 = dev->key_phys_base;
453 dev->hw_desc[0]->next = dev->hw_phys_desc[1];
454 }
455 dev->hw_desc[0]->hdr = sahara_aes_key_hdr(dev);
456
457 dev->nb_in_sg = sahara_sg_length(dev->in_sg, dev->total);
458 dev->nb_out_sg = sahara_sg_length(dev->out_sg, dev->total);
459 if ((dev->nb_in_sg + dev->nb_out_sg) > SAHARA_MAX_HW_LINK) {
460 dev_err(dev->device, "not enough hw links (%d)\n",
461 dev->nb_in_sg + dev->nb_out_sg);
462 return -EINVAL;
463 }
464
465 ret = dma_map_sg(dev->device, dev->in_sg, dev->nb_in_sg,
466 DMA_TO_DEVICE);
467 if (ret != dev->nb_in_sg) {
468 dev_err(dev->device, "couldn't map in sg\n");
469 goto unmap_in;
470 }
471 ret = dma_map_sg(dev->device, dev->out_sg, dev->nb_out_sg,
472 DMA_FROM_DEVICE);
473 if (ret != dev->nb_out_sg) {
474 dev_err(dev->device, "couldn't map out sg\n");
475 goto unmap_out;
476 }
477
478 /* Create input links */
479 dev->hw_desc[1]->p1 = dev->hw_phys_link[0];
480 sg = dev->in_sg;
481 for (i = 0; i < dev->nb_in_sg; i++) {
482 dev->hw_link[i]->len = sg->length;
483 dev->hw_link[i]->p = sg->dma_address;
484 if (i == (dev->nb_in_sg - 1)) {
485 dev->hw_link[i]->next = 0;
486 } else {
487 dev->hw_link[i]->next = dev->hw_phys_link[i + 1];
488 sg = sg_next(sg);
489 }
490 }
491
492 /* Create output links */
493 dev->hw_desc[1]->p2 = dev->hw_phys_link[i];
494 sg = dev->out_sg;
495 for (j = i; j < dev->nb_out_sg + i; j++) {
496 dev->hw_link[j]->len = sg->length;
497 dev->hw_link[j]->p = sg->dma_address;
498 if (j == (dev->nb_out_sg + i - 1)) {
499 dev->hw_link[j]->next = 0;
500 } else {
501 dev->hw_link[j]->next = dev->hw_phys_link[j + 1];
502 sg = sg_next(sg);
503 }
504 }
505
506 /* Fill remaining fields of hw_desc[1] */
507 dev->hw_desc[1]->hdr = sahara_aes_data_link_hdr(dev);
508 dev->hw_desc[1]->len1 = dev->total;
509 dev->hw_desc[1]->len2 = dev->total;
510 dev->hw_desc[1]->next = 0;
511
512 sahara_dump_descriptors(dev);
513 sahara_dump_links(dev);
514
515 /* Start processing descriptor chain. */
516 mod_timer(&dev->watchdog,
517 jiffies + msecs_to_jiffies(SAHARA_TIMEOUT_MS));
518 sahara_write(dev, dev->hw_phys_desc[0], SAHARA_REG_DAR);
519
520 return 0;
521
522unmap_out:
523 dma_unmap_sg(dev->device, dev->out_sg, dev->nb_out_sg,
524 DMA_TO_DEVICE);
525unmap_in:
526 dma_unmap_sg(dev->device, dev->in_sg, dev->nb_in_sg,
527 DMA_FROM_DEVICE);
528
529 return -EINVAL;
530}
531
532static void sahara_aes_queue_task(unsigned long data)
533{
534 struct sahara_dev *dev = (struct sahara_dev *)data;
535 struct crypto_async_request *async_req, *backlog;
536 struct sahara_ctx *ctx;
537 struct sahara_aes_reqctx *rctx;
538 struct ablkcipher_request *req;
539 int ret;
540
541 spin_lock(&dev->lock);
542 backlog = crypto_get_backlog(&dev->queue);
543 async_req = crypto_dequeue_request(&dev->queue);
544 if (!async_req)
545 clear_bit(FLAGS_BUSY, &dev->flags);
546 spin_unlock(&dev->lock);
547
548 if (!async_req)
549 return;
550
551 if (backlog)
552 backlog->complete(backlog, -EINPROGRESS);
553
554 req = ablkcipher_request_cast(async_req);
555
556 /* Request is ready to be dispatched by the device */
557 dev_dbg(dev->device,
558 "dispatch request (nbytes=%d, src=%p, dst=%p)\n",
559 req->nbytes, req->src, req->dst);
560
561 /* assign new request to device */
562 dev->req = req;
563 dev->total = req->nbytes;
564 dev->in_sg = req->src;
565 dev->out_sg = req->dst;
566
567 rctx = ablkcipher_request_ctx(req);
568 ctx = crypto_ablkcipher_ctx(crypto_ablkcipher_reqtfm(req));
569 rctx->mode &= FLAGS_MODE_MASK;
570 dev->flags = (dev->flags & ~FLAGS_MODE_MASK) | rctx->mode;
571
572 if ((dev->flags & FLAGS_CBC) && req->info)
573 memcpy(dev->iv_base, req->info, AES_KEYSIZE_128);
574
575 /* assign new context to device */
576 ctx->dev = dev;
577 dev->ctx = ctx;
578
579 ret = sahara_hw_descriptor_create(dev);
580 if (ret < 0) {
581 spin_lock(&dev->lock);
582 clear_bit(FLAGS_BUSY, &dev->flags);
583 spin_unlock(&dev->lock);
584 dev->req->base.complete(&dev->req->base, ret);
585 }
586}
587
588static int sahara_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
589 unsigned int keylen)
590{
591 struct sahara_ctx *ctx = crypto_ablkcipher_ctx(tfm);
592 int ret;
593
594 ctx->keylen = keylen;
595
596 /* SAHARA only supports 128bit keys */
597 if (keylen == AES_KEYSIZE_128) {
598 memcpy(ctx->key, key, keylen);
599 ctx->flags |= FLAGS_NEW_KEY;
600 return 0;
601 }
602
603 if (keylen != AES_KEYSIZE_128 &&
604 keylen != AES_KEYSIZE_192 && keylen != AES_KEYSIZE_256)
605 return -EINVAL;
606
607 /*
608 * The requested key size is not supported by HW, do a fallback.
609 */
610 ctx->fallback->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
611 ctx->fallback->base.crt_flags |=
612 (tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
613
614 ret = crypto_ablkcipher_setkey(ctx->fallback, key, keylen);
615 if (ret) {
616 struct crypto_tfm *tfm_aux = crypto_ablkcipher_tfm(tfm);
617
618 tfm_aux->crt_flags &= ~CRYPTO_TFM_RES_MASK;
619 tfm_aux->crt_flags |=
620 (ctx->fallback->base.crt_flags & CRYPTO_TFM_RES_MASK);
621 }
622 return ret;
623}
624
625static int sahara_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
626{
627 struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
628 crypto_ablkcipher_reqtfm(req));
629 struct sahara_aes_reqctx *rctx = ablkcipher_request_ctx(req);
630 struct sahara_dev *dev = dev_ptr;
631 int err = 0;
632 int busy;
633
634 dev_dbg(dev->device, "nbytes: %d, enc: %d, cbc: %d\n",
635 req->nbytes, !!(mode & FLAGS_ENCRYPT), !!(mode & FLAGS_CBC));
636
637 if (!IS_ALIGNED(req->nbytes, AES_BLOCK_SIZE)) {
638 dev_err(dev->device,
639 "request size is not exact amount of AES blocks\n");
640 return -EINVAL;
641 }
642
643 ctx->dev = dev;
644
645 rctx->mode = mode;
646 spin_lock_bh(&dev->lock);
647 err = ablkcipher_enqueue_request(&dev->queue, req);
648 busy = test_and_set_bit(FLAGS_BUSY, &dev->flags);
649 spin_unlock_bh(&dev->lock);
650
651 if (!busy)
652 tasklet_schedule(&dev->queue_task);
653
654 return err;
655}
656
657static int sahara_aes_ecb_encrypt(struct ablkcipher_request *req)
658{
659 struct crypto_tfm *tfm =
660 crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
661 struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
662 crypto_ablkcipher_reqtfm(req));
663 int err;
664
665 if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
666 ablkcipher_request_set_tfm(req, ctx->fallback);
667 err = crypto_ablkcipher_encrypt(req);
668 ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
669 return err;
670 }
671
672 return sahara_aes_crypt(req, FLAGS_ENCRYPT);
673}
674
675static int sahara_aes_ecb_decrypt(struct ablkcipher_request *req)
676{
677 struct crypto_tfm *tfm =
678 crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
679 struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
680 crypto_ablkcipher_reqtfm(req));
681 int err;
682
683 if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
684 ablkcipher_request_set_tfm(req, ctx->fallback);
685 err = crypto_ablkcipher_decrypt(req);
686 ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
687 return err;
688 }
689
690 return sahara_aes_crypt(req, 0);
691}
692
693static int sahara_aes_cbc_encrypt(struct ablkcipher_request *req)
694{
695 struct crypto_tfm *tfm =
696 crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
697 struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
698 crypto_ablkcipher_reqtfm(req));
699 int err;
700
701 if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
702 ablkcipher_request_set_tfm(req, ctx->fallback);
703 err = crypto_ablkcipher_encrypt(req);
704 ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
705 return err;
706 }
707
708 return sahara_aes_crypt(req, FLAGS_ENCRYPT | FLAGS_CBC);
709}
710
711static int sahara_aes_cbc_decrypt(struct ablkcipher_request *req)
712{
713 struct crypto_tfm *tfm =
714 crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
715 struct sahara_ctx *ctx = crypto_ablkcipher_ctx(
716 crypto_ablkcipher_reqtfm(req));
717 int err;
718
719 if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
720 ablkcipher_request_set_tfm(req, ctx->fallback);
721 err = crypto_ablkcipher_decrypt(req);
722 ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
723 return err;
724 }
725
726 return sahara_aes_crypt(req, FLAGS_CBC);
727}
728
729static int sahara_aes_cra_init(struct crypto_tfm *tfm)
730{
731 const char *name = tfm->__crt_alg->cra_name;
732 struct sahara_ctx *ctx = crypto_tfm_ctx(tfm);
733
734 ctx->fallback = crypto_alloc_ablkcipher(name, 0,
735 CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);
736 if (IS_ERR(ctx->fallback)) {
737 pr_err("Error allocating fallback algo %s\n", name);
738 return PTR_ERR(ctx->fallback);
739 }
740
741 tfm->crt_ablkcipher.reqsize = sizeof(struct sahara_aes_reqctx);
742
743 return 0;
744}
745
746static void sahara_aes_cra_exit(struct crypto_tfm *tfm)
747{
748 struct sahara_ctx *ctx = crypto_tfm_ctx(tfm);
749
750 if (ctx->fallback)
751 crypto_free_ablkcipher(ctx->fallback);
752 ctx->fallback = NULL;
753}
754
755static struct crypto_alg aes_algs[] = {
756{
757 .cra_name = "ecb(aes)",
758 .cra_driver_name = "sahara-ecb-aes",
759 .cra_priority = 300,
760 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER |
761 CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
762 .cra_blocksize = AES_BLOCK_SIZE,
763 .cra_ctxsize = sizeof(struct sahara_ctx),
764 .cra_alignmask = 0x0,
765 .cra_type = &crypto_ablkcipher_type,
766 .cra_module = THIS_MODULE,
767 .cra_init = sahara_aes_cra_init,
768 .cra_exit = sahara_aes_cra_exit,
769 .cra_u.ablkcipher = {
770 .min_keysize = AES_MIN_KEY_SIZE ,
771 .max_keysize = AES_MAX_KEY_SIZE,
772 .setkey = sahara_aes_setkey,
773 .encrypt = sahara_aes_ecb_encrypt,
774 .decrypt = sahara_aes_ecb_decrypt,
775 }
776}, {
777 .cra_name = "cbc(aes)",
778 .cra_driver_name = "sahara-cbc-aes",
779 .cra_priority = 300,
780 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER |
781 CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK,
782 .cra_blocksize = AES_BLOCK_SIZE,
783 .cra_ctxsize = sizeof(struct sahara_ctx),
784 .cra_alignmask = 0x0,
785 .cra_type = &crypto_ablkcipher_type,
786 .cra_module = THIS_MODULE,
787 .cra_init = sahara_aes_cra_init,
788 .cra_exit = sahara_aes_cra_exit,
789 .cra_u.ablkcipher = {
790 .min_keysize = AES_MIN_KEY_SIZE ,
791 .max_keysize = AES_MAX_KEY_SIZE,
792 .ivsize = AES_BLOCK_SIZE,
793 .setkey = sahara_aes_setkey,
794 .encrypt = sahara_aes_cbc_encrypt,
795 .decrypt = sahara_aes_cbc_decrypt,
796 }
797}
798};
799
800static irqreturn_t sahara_irq_handler(int irq, void *data)
801{
802 struct sahara_dev *dev = (struct sahara_dev *)data;
803 unsigned int stat = sahara_read(dev, SAHARA_REG_STATUS);
804 unsigned int err = sahara_read(dev, SAHARA_REG_ERRSTATUS);
805
806 del_timer(&dev->watchdog);
807
808 sahara_write(dev, SAHARA_CMD_CLEAR_INT | SAHARA_CMD_CLEAR_ERR,
809 SAHARA_REG_CMD);
810
811 sahara_decode_status(dev, stat);
812
813 if (SAHARA_STATUS_GET_STATE(stat) == SAHARA_STATE_BUSY) {
814 return IRQ_NONE;
815 } else if (SAHARA_STATUS_GET_STATE(stat) == SAHARA_STATE_COMPLETE) {
816 dev->error = 0;
817 } else {
818 sahara_decode_error(dev, err);
819 dev->error = -EINVAL;
820 }
821
822 tasklet_schedule(&dev->done_task);
823
824 return IRQ_HANDLED;
825}
826
827
828static int sahara_register_algs(struct sahara_dev *dev)
829{
830 int err, i, j;
831
832 for (i = 0; i < ARRAY_SIZE(aes_algs); i++) {
833 INIT_LIST_HEAD(&aes_algs[i].cra_list);
834 err = crypto_register_alg(&aes_algs[i]);
835 if (err)
836 goto err_aes_algs;
837 }
838
839 return 0;
840
841err_aes_algs:
842 for (j = 0; j < i; j++)
843 crypto_unregister_alg(&aes_algs[j]);
844
845 return err;
846}
847
848static void sahara_unregister_algs(struct sahara_dev *dev)
849{
850 int i;
851
852 for (i = 0; i < ARRAY_SIZE(aes_algs); i++)
853 crypto_unregister_alg(&aes_algs[i]);
854}
855
856static struct platform_device_id sahara_platform_ids[] = {
857 { .name = "sahara-imx27" },
858 { /* sentinel */ }
859};
860MODULE_DEVICE_TABLE(platform, sahara_platform_ids);
861
862static struct of_device_id sahara_dt_ids[] = {
863 { .compatible = "fsl,imx27-sahara" },
864 { /* sentinel */ }
865};
Arnd Bergmann68be0b1a2013-06-03 23:57:37 +0200866MODULE_DEVICE_TABLE(of, sahara_dt_ids);
Javier Martin5de88752013-03-01 12:37:53 +0100867
868static int sahara_probe(struct platform_device *pdev)
869{
870 struct sahara_dev *dev;
871 struct resource *res;
872 u32 version;
873 int irq;
874 int err;
875 int i;
876
877 dev = devm_kzalloc(&pdev->dev, sizeof(struct sahara_dev), GFP_KERNEL);
878 if (dev == NULL) {
879 dev_err(&pdev->dev, "unable to alloc data struct.\n");
880 return -ENOMEM;
881 }
882
883 dev->device = &pdev->dev;
884 platform_set_drvdata(pdev, dev);
885
886 /* Get the base address */
887 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
888 if (!res) {
889 dev_err(&pdev->dev, "failed to get memory region resource\n");
890 return -ENODEV;
891 }
892
893 if (devm_request_mem_region(&pdev->dev, res->start,
894 resource_size(res), SAHARA_NAME) == NULL) {
895 dev_err(&pdev->dev, "failed to request memory region\n");
896 return -ENOENT;
897 }
898 dev->regs_base = devm_ioremap(&pdev->dev, res->start,
899 resource_size(res));
900 if (!dev->regs_base) {
901 dev_err(&pdev->dev, "failed to ioremap address region\n");
902 return -ENOENT;
903 }
904
905 /* Get the IRQ */
906 irq = platform_get_irq(pdev, 0);
907 if (irq < 0) {
908 dev_err(&pdev->dev, "failed to get irq resource\n");
909 return irq;
910 }
911
912 if (devm_request_irq(&pdev->dev, irq, sahara_irq_handler,
913 0, SAHARA_NAME, dev) < 0) {
914 dev_err(&pdev->dev, "failed to request irq\n");
915 return -ENOENT;
916 }
917
918 /* clocks */
919 dev->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
920 if (IS_ERR(dev->clk_ipg)) {
921 dev_err(&pdev->dev, "Could not get ipg clock\n");
922 return PTR_ERR(dev->clk_ipg);
923 }
924
925 dev->clk_ahb = devm_clk_get(&pdev->dev, "ahb");
926 if (IS_ERR(dev->clk_ahb)) {
927 dev_err(&pdev->dev, "Could not get ahb clock\n");
928 return PTR_ERR(dev->clk_ahb);
929 }
930
931 /* Allocate HW descriptors */
932 dev->hw_desc[0] = dma_alloc_coherent(&pdev->dev,
933 SAHARA_MAX_HW_DESC * sizeof(struct sahara_hw_desc),
934 &dev->hw_phys_desc[0], GFP_KERNEL);
935 if (!dev->hw_desc[0]) {
936 dev_err(&pdev->dev, "Could not allocate hw descriptors\n");
937 return -ENOMEM;
938 }
939 dev->hw_desc[1] = dev->hw_desc[0] + 1;
940 dev->hw_phys_desc[1] = dev->hw_phys_desc[0] +
941 sizeof(struct sahara_hw_desc);
942
943 /* Allocate space for iv and key */
944 dev->key_base = dma_alloc_coherent(&pdev->dev, 2 * AES_KEYSIZE_128,
945 &dev->key_phys_base, GFP_KERNEL);
946 if (!dev->key_base) {
947 dev_err(&pdev->dev, "Could not allocate memory for key\n");
948 err = -ENOMEM;
949 goto err_key;
950 }
951 dev->iv_base = dev->key_base + AES_KEYSIZE_128;
952 dev->iv_phys_base = dev->key_phys_base + AES_KEYSIZE_128;
953
954 /* Allocate space for HW links */
955 dev->hw_link[0] = dma_alloc_coherent(&pdev->dev,
956 SAHARA_MAX_HW_LINK * sizeof(struct sahara_hw_link),
957 &dev->hw_phys_link[0], GFP_KERNEL);
958 if (!dev->hw_link) {
959 dev_err(&pdev->dev, "Could not allocate hw links\n");
960 err = -ENOMEM;
961 goto err_link;
962 }
963 for (i = 1; i < SAHARA_MAX_HW_LINK; i++) {
964 dev->hw_phys_link[i] = dev->hw_phys_link[i - 1] +
965 sizeof(struct sahara_hw_link);
966 dev->hw_link[i] = dev->hw_link[i - 1] + 1;
967 }
968
969 crypto_init_queue(&dev->queue, SAHARA_QUEUE_LENGTH);
970
971 dev_ptr = dev;
972
973 tasklet_init(&dev->queue_task, sahara_aes_queue_task,
974 (unsigned long)dev);
975 tasklet_init(&dev->done_task, sahara_aes_done_task,
976 (unsigned long)dev);
977
978 init_timer(&dev->watchdog);
979 dev->watchdog.function = &sahara_watchdog;
980 dev->watchdog.data = (unsigned long)dev;
981
982 clk_prepare_enable(dev->clk_ipg);
983 clk_prepare_enable(dev->clk_ahb);
984
985 version = sahara_read(dev, SAHARA_REG_VERSION);
986 if (version != SAHARA_VERSION_3) {
987 dev_err(&pdev->dev, "SAHARA version %d not supported\n",
988 version);
989 err = -ENODEV;
990 goto err_algs;
991 }
992
993 sahara_write(dev, SAHARA_CMD_RESET | SAHARA_CMD_MODE_BATCH,
994 SAHARA_REG_CMD);
995 sahara_write(dev, SAHARA_CONTROL_SET_THROTTLE(0) |
996 SAHARA_CONTROL_SET_MAXBURST(8) |
997 SAHARA_CONTROL_RNG_AUTORSD |
998 SAHARA_CONTROL_ENABLE_INT,
999 SAHARA_REG_CONTROL);
1000
1001 err = sahara_register_algs(dev);
1002 if (err)
1003 goto err_algs;
1004
1005 dev_info(&pdev->dev, "SAHARA version %d initialized\n", version);
1006
1007 return 0;
1008
1009err_algs:
1010 dma_free_coherent(&pdev->dev,
1011 SAHARA_MAX_HW_LINK * sizeof(struct sahara_hw_link),
1012 dev->hw_link[0], dev->hw_phys_link[0]);
1013 clk_disable_unprepare(dev->clk_ipg);
1014 clk_disable_unprepare(dev->clk_ahb);
1015 dev_ptr = NULL;
1016err_link:
1017 dma_free_coherent(&pdev->dev,
1018 2 * AES_KEYSIZE_128,
1019 dev->key_base, dev->key_phys_base);
1020err_key:
1021 dma_free_coherent(&pdev->dev,
1022 SAHARA_MAX_HW_DESC * sizeof(struct sahara_hw_desc),
1023 dev->hw_desc[0], dev->hw_phys_desc[0]);
1024
1025 return err;
1026}
1027
1028static int sahara_remove(struct platform_device *pdev)
1029{
1030 struct sahara_dev *dev = platform_get_drvdata(pdev);
1031
1032 dma_free_coherent(&pdev->dev,
1033 SAHARA_MAX_HW_LINK * sizeof(struct sahara_hw_link),
1034 dev->hw_link[0], dev->hw_phys_link[0]);
1035 dma_free_coherent(&pdev->dev,
1036 2 * AES_KEYSIZE_128,
1037 dev->key_base, dev->key_phys_base);
1038 dma_free_coherent(&pdev->dev,
1039 SAHARA_MAX_HW_DESC * sizeof(struct sahara_hw_desc),
1040 dev->hw_desc[0], dev->hw_phys_desc[0]);
1041
1042 tasklet_kill(&dev->done_task);
1043 tasklet_kill(&dev->queue_task);
1044
1045 sahara_unregister_algs(dev);
1046
1047 clk_disable_unprepare(dev->clk_ipg);
1048 clk_disable_unprepare(dev->clk_ahb);
1049
1050 dev_ptr = NULL;
1051
1052 return 0;
1053}
1054
1055static struct platform_driver sahara_driver = {
1056 .probe = sahara_probe,
1057 .remove = sahara_remove,
1058 .driver = {
1059 .name = SAHARA_NAME,
1060 .owner = THIS_MODULE,
1061 .of_match_table = of_match_ptr(sahara_dt_ids),
1062 },
1063 .id_table = sahara_platform_ids,
1064};
1065
1066module_platform_driver(sahara_driver);
1067
1068MODULE_LICENSE("GPL");
1069MODULE_AUTHOR("Javier Martin <javier.martin@vista-silicon.com>");
1070MODULE_DESCRIPTION("SAHARA2 HW crypto accelerator");