1 /*
2 * drivers/crypto/tegra-aes.c
3 *
4 * Driver for NVIDIA Tegra AES hardware engine residing inside the
5 * Bit Stream Engine for Video (BSEV) hardware block.
6 *
7 * The programming sequence for this engine is with the help
8 * of commands which travel via a command queue residing between the
9 * CPU and the BSEV block. The BSEV engine has an internal RAM (VRAM)
10 * where the final input plaintext, keys and the IV have to be copied
11 * before starting the encrypt/decrypt operation.
12 *
13 * Copyright (c) 2010, NVIDIA Corporation.
14 *
15 * This program is free software; you can redistribute it and/or modify
16 * it under the terms of the GNU General Public License as published by
17 * the Free Software Foundation; either version 2 of the License, or
18 * (at your option) any later version.
19 *
20 * This program is distributed in the hope that it will be useful, but WITHOUT
21 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
22 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
23 * more details.
24 *
25 * You should have received a copy of the GNU General Public License along
26 * with this program; if not, write to the Free Software Foundation, Inc.,
27 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
28 */
29
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/errno.h>
33 #include <linux/kernel.h>
34 #include <linux/clk.h>
35 #include <linux/platform_device.h>
36 #include <linux/scatterlist.h>
37 #include <linux/dma-mapping.h>
38 #include <linux/io.h>
39 #include <linux/mutex.h>
40 #include <linux/interrupt.h>
41 #include <linux/completion.h>
42 #include <linux/workqueue.h>
43
44 #include <mach/clk.h>
45
46 #include <crypto/scatterwalk.h>
47 #include <crypto/aes.h>
48 #include <crypto/internal/rng.h>
49
50 #include "tegra-aes.h"
51
52 #define FLAGS_MODE_MASK 0x00FF
53 #define FLAGS_ENCRYPT BIT(0)
54 #define FLAGS_CBC BIT(1)
55 #define FLAGS_GIV BIT(2)
56 #define FLAGS_RNG BIT(3)
57 #define FLAGS_OFB BIT(4)
58 #define FLAGS_NEW_KEY BIT(5)
59 #define FLAGS_NEW_IV BIT(6)
60 #define FLAGS_INIT BIT(7)
61 #define FLAGS_FAST BIT(8)
62 #define FLAGS_BUSY 9
63
64 /*
65 * Defines AES engine Max process bytes size in one go, which takes 1 msec.
66 * AES engine spends about 176 cycles/16-bytes or 11 cycles/byte
67 * The duration CPU can use the BSE to 1 msec, then the number of available
68 * cycles of AVP/BSE is 216K. In this duration, AES can process 216/11 ~= 19KB
69 * Based on this AES_HW_DMA_BUFFER_SIZE_BYTES is configured to 16KB.
70 */
71 #define AES_HW_DMA_BUFFER_SIZE_BYTES 0x4000
72
73 /*
74 * The key table length is 64 bytes
75 * (This includes first upto 32 bytes key + 16 bytes original initial vector
76 * and 16 bytes updated initial vector)
77 */
78 #define AES_HW_KEY_TABLE_LENGTH_BYTES 64
79
80 /*
81 * The memory being used is divides as follows:
82 * 1. Key - 32 bytes
83 * 2. Original IV - 16 bytes
84 * 3. Updated IV - 16 bytes
85 * 4. Key schedule - 256 bytes
86 *
87 * 1+2+3 constitute the hw key table.
88 */
89 #define AES_HW_IV_SIZE 16
90 #define AES_HW_KEYSCHEDULE_LEN 256
91 #define AES_IVKEY_SIZE (AES_HW_KEY_TABLE_LENGTH_BYTES + AES_HW_KEYSCHEDULE_LEN)
92
93 /* Define commands required for AES operation */
94 enum {
95 CMD_BLKSTARTENGINE = 0x0E,
96 CMD_DMASETUP = 0x10,
97 CMD_DMACOMPLETE = 0x11,
98 CMD_SETTABLE = 0x15,
99 CMD_MEMDMAVD = 0x22,
100 };
101
102 /* Define sub-commands */
103 enum {
104 SUBCMD_VRAM_SEL = 0x1,
105 SUBCMD_CRYPTO_TABLE_SEL = 0x3,
106 SUBCMD_KEY_TABLE_SEL = 0x8,
107 };
108
109 /* memdma_vd command */
110 #define MEMDMA_DIR_DTOVRAM 0 /* sdram -> vram */
111 #define MEMDMA_DIR_VTODRAM 1 /* vram -> sdram */
112 #define MEMDMA_DIR_SHIFT 25
113 #define MEMDMA_NUM_WORDS_SHIFT 12
114
115 /* command queue bit shifts */
116 enum {
117 CMDQ_KEYTABLEADDR_SHIFT = 0,
118 CMDQ_KEYTABLEID_SHIFT = 17,
119 CMDQ_VRAMSEL_SHIFT = 23,
120 CMDQ_TABLESEL_SHIFT = 24,
121 CMDQ_OPCODE_SHIFT = 26,
122 };
123
124 /*
125 * The secure key slot contains a unique secure key generated
126 * and loaded by the bootloader. This slot is marked as non-accessible
127 * to the kernel.
128 */
129 #define SSK_SLOT_NUM 4
130
131 #define AES_NR_KEYSLOTS 8
132 #define TEGRA_AES_QUEUE_LENGTH 50
133 #define DEFAULT_RNG_BLK_SZ 16
134
135 /* The command queue depth */
136 #define AES_HW_MAX_ICQ_LENGTH 5
137
138 struct tegra_aes_slot {
139 struct list_head node;
140 int slot_num;
141 };
142
143 static struct tegra_aes_slot ssk = {
144 .slot_num = SSK_SLOT_NUM,
145 };
146
147 struct tegra_aes_reqctx {
148 unsigned long mode;
149 };
150
151 struct tegra_aes_dev {
152 struct device *dev;
153 void __iomem *io_base;
154 dma_addr_t ivkey_phys_base;
155 void __iomem *ivkey_base;
156 struct clk *aes_clk;
157 struct tegra_aes_ctx *ctx;
158 int irq;
159 unsigned long flags;
160 struct completion op_complete;
161 u32 *buf_in;
162 dma_addr_t dma_buf_in;
163 u32 *buf_out;
164 dma_addr_t dma_buf_out;
165 u8 *iv;
166 u8 dt[DEFAULT_RNG_BLK_SZ];
167 int ivlen;
168 u64 ctr;
169 spinlock_t lock;
170 struct crypto_queue queue;
171 struct tegra_aes_slot *slots;
172 struct ablkcipher_request *req;
173 size_t total;
174 struct scatterlist *in_sg;
175 size_t in_offset;
176 struct scatterlist *out_sg;
177 size_t out_offset;
178 };
179
180 static struct tegra_aes_dev *aes_dev;
181
182 struct tegra_aes_ctx {
183 struct tegra_aes_dev *dd;
184 unsigned long flags;
185 struct tegra_aes_slot *slot;
186 u8 key[AES_MAX_KEY_SIZE];
187 size_t keylen;
188 };
189
190 static struct tegra_aes_ctx rng_ctx = {
191 .flags = FLAGS_NEW_KEY,
192 .keylen = AES_KEYSIZE_128,
193 };
194
195 /* keep registered devices data here */
196 static struct list_head dev_list;
197 static DEFINE_SPINLOCK(list_lock);
198 static DEFINE_MUTEX(aes_lock);
199
200 static void aes_workqueue_handler(struct work_struct *work);
201 static DECLARE_WORK(aes_work, aes_workqueue_handler);
202 static struct workqueue_struct *aes_wq;
203
204 extern unsigned long long tegra_chip_uid(void);
205
aes_readl(struct tegra_aes_dev * dd,u32 offset)206 static inline u32 aes_readl(struct tegra_aes_dev *dd, u32 offset)
207 {
208 return readl(dd->io_base + offset);
209 }
210
aes_writel(struct tegra_aes_dev * dd,u32 val,u32 offset)211 static inline void aes_writel(struct tegra_aes_dev *dd, u32 val, u32 offset)
212 {
213 writel(val, dd->io_base + offset);
214 }
215
aes_start_crypt(struct tegra_aes_dev * dd,u32 in_addr,u32 out_addr,int nblocks,int mode,bool upd_iv)216 static int aes_start_crypt(struct tegra_aes_dev *dd, u32 in_addr, u32 out_addr,
217 int nblocks, int mode, bool upd_iv)
218 {
219 u32 cmdq[AES_HW_MAX_ICQ_LENGTH];
220 int i, eng_busy, icq_empty, ret;
221 u32 value;
222
223 /* reset all the interrupt bits */
224 aes_writel(dd, 0xFFFFFFFF, TEGRA_AES_INTR_STATUS);
225
226 /* enable error, dma xfer complete interrupts */
227 aes_writel(dd, 0x33, TEGRA_AES_INT_ENB);
228
229 cmdq[0] = CMD_DMASETUP << CMDQ_OPCODE_SHIFT;
230 cmdq[1] = in_addr;
231 cmdq[2] = CMD_BLKSTARTENGINE << CMDQ_OPCODE_SHIFT | (nblocks-1);
232 cmdq[3] = CMD_DMACOMPLETE << CMDQ_OPCODE_SHIFT;
233
234 value = aes_readl(dd, TEGRA_AES_CMDQUE_CONTROL);
235 /* access SDRAM through AHB */
236 value &= ~TEGRA_AES_CMDQ_CTRL_SRC_STM_SEL_FIELD;
237 value &= ~TEGRA_AES_CMDQ_CTRL_DST_STM_SEL_FIELD;
238 value |= TEGRA_AES_CMDQ_CTRL_SRC_STM_SEL_FIELD |
239 TEGRA_AES_CMDQ_CTRL_DST_STM_SEL_FIELD |
240 TEGRA_AES_CMDQ_CTRL_ICMDQEN_FIELD;
241 aes_writel(dd, value, TEGRA_AES_CMDQUE_CONTROL);
242 dev_dbg(dd->dev, "cmd_q_ctrl=0x%x", value);
243
244 value = (0x1 << TEGRA_AES_SECURE_INPUT_ALG_SEL_SHIFT) |
245 ((dd->ctx->keylen * 8) <<
246 TEGRA_AES_SECURE_INPUT_KEY_LEN_SHIFT) |
247 ((u32)upd_iv << TEGRA_AES_SECURE_IV_SELECT_SHIFT);
248
249 if (mode & FLAGS_CBC) {
250 value |= ((((mode & FLAGS_ENCRYPT) ? 2 : 3)
251 << TEGRA_AES_SECURE_XOR_POS_SHIFT) |
252 (((mode & FLAGS_ENCRYPT) ? 2 : 3)
253 << TEGRA_AES_SECURE_VCTRAM_SEL_SHIFT) |
254 ((mode & FLAGS_ENCRYPT) ? 1 : 0)
255 << TEGRA_AES_SECURE_CORE_SEL_SHIFT);
256 } else if (mode & FLAGS_OFB) {
257 value |= ((TEGRA_AES_SECURE_XOR_POS_FIELD) |
258 (2 << TEGRA_AES_SECURE_INPUT_SEL_SHIFT) |
259 (TEGRA_AES_SECURE_CORE_SEL_FIELD));
260 } else if (mode & FLAGS_RNG) {
261 value |= (((mode & FLAGS_ENCRYPT) ? 1 : 0)
262 << TEGRA_AES_SECURE_CORE_SEL_SHIFT |
263 TEGRA_AES_SECURE_RNG_ENB_FIELD);
264 } else {
265 value |= (((mode & FLAGS_ENCRYPT) ? 1 : 0)
266 << TEGRA_AES_SECURE_CORE_SEL_SHIFT);
267 }
268
269 dev_dbg(dd->dev, "secure_in_sel=0x%x", value);
270 aes_writel(dd, value, TEGRA_AES_SECURE_INPUT_SELECT);
271
272 aes_writel(dd, out_addr, TEGRA_AES_SECURE_DEST_ADDR);
273 INIT_COMPLETION(dd->op_complete);
274
275 for (i = 0; i < AES_HW_MAX_ICQ_LENGTH - 1; i++) {
276 do {
277 value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
278 eng_busy = value & TEGRA_AES_ENGINE_BUSY_FIELD;
279 icq_empty = value & TEGRA_AES_ICQ_EMPTY_FIELD;
280 } while (eng_busy & (!icq_empty));
281 aes_writel(dd, cmdq[i], TEGRA_AES_ICMDQUE_WR);
282 }
283
284 ret = wait_for_completion_timeout(&dd->op_complete,
285 msecs_to_jiffies(150));
286 if (ret == 0) {
287 dev_err(dd->dev, "timed out (0x%x)\n",
288 aes_readl(dd, TEGRA_AES_INTR_STATUS));
289 return -ETIMEDOUT;
290 }
291
292 aes_writel(dd, cmdq[AES_HW_MAX_ICQ_LENGTH - 1], TEGRA_AES_ICMDQUE_WR);
293 return 0;
294 }
295
aes_release_key_slot(struct tegra_aes_slot * slot)296 static void aes_release_key_slot(struct tegra_aes_slot *slot)
297 {
298 if (slot->slot_num == SSK_SLOT_NUM)
299 return;
300
301 spin_lock(&list_lock);
302 list_add_tail(&slot->node, &dev_list);
303 slot = NULL;
304 spin_unlock(&list_lock);
305 }
306
aes_find_key_slot(void)307 static struct tegra_aes_slot *aes_find_key_slot(void)
308 {
309 struct tegra_aes_slot *slot = NULL;
310 struct list_head *new_head;
311 int empty;
312
313 spin_lock(&list_lock);
314 empty = list_empty(&dev_list);
315 if (!empty) {
316 slot = list_entry(&dev_list, struct tegra_aes_slot, node);
317 new_head = dev_list.next;
318 list_del(&dev_list);
319 dev_list.next = new_head->next;
320 dev_list.prev = NULL;
321 }
322 spin_unlock(&list_lock);
323
324 return slot;
325 }
326
aes_set_key(struct tegra_aes_dev * dd)327 static int aes_set_key(struct tegra_aes_dev *dd)
328 {
329 u32 value, cmdq[2];
330 struct tegra_aes_ctx *ctx = dd->ctx;
331 int eng_busy, icq_empty, dma_busy;
332 bool use_ssk = false;
333
334 /* use ssk? */
335 if (!dd->ctx->slot) {
336 dev_dbg(dd->dev, "using ssk");
337 dd->ctx->slot = &ssk;
338 use_ssk = true;
339 }
340
341 /* enable key schedule generation in hardware */
342 value = aes_readl(dd, TEGRA_AES_SECURE_CONFIG_EXT);
343 value &= ~TEGRA_AES_SECURE_KEY_SCH_DIS_FIELD;
344 aes_writel(dd, value, TEGRA_AES_SECURE_CONFIG_EXT);
345
346 /* select the key slot */
347 value = aes_readl(dd, TEGRA_AES_SECURE_CONFIG);
348 value &= ~TEGRA_AES_SECURE_KEY_INDEX_FIELD;
349 value |= (ctx->slot->slot_num << TEGRA_AES_SECURE_KEY_INDEX_SHIFT);
350 aes_writel(dd, value, TEGRA_AES_SECURE_CONFIG);
351
352 if (use_ssk)
353 return 0;
354
355 /* copy the key table from sdram to vram */
356 cmdq[0] = CMD_MEMDMAVD << CMDQ_OPCODE_SHIFT |
357 MEMDMA_DIR_DTOVRAM << MEMDMA_DIR_SHIFT |
358 AES_HW_KEY_TABLE_LENGTH_BYTES / sizeof(u32) <<
359 MEMDMA_NUM_WORDS_SHIFT;
360 cmdq[1] = (u32)dd->ivkey_phys_base;
361
362 aes_writel(dd, cmdq[0], TEGRA_AES_ICMDQUE_WR);
363 aes_writel(dd, cmdq[1], TEGRA_AES_ICMDQUE_WR);
364
365 do {
366 value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
367 eng_busy = value & TEGRA_AES_ENGINE_BUSY_FIELD;
368 icq_empty = value & TEGRA_AES_ICQ_EMPTY_FIELD;
369 dma_busy = value & TEGRA_AES_DMA_BUSY_FIELD;
370 } while (eng_busy & (!icq_empty) & dma_busy);
371
372 /* settable command to get key into internal registers */
373 value = CMD_SETTABLE << CMDQ_OPCODE_SHIFT |
374 SUBCMD_CRYPTO_TABLE_SEL << CMDQ_TABLESEL_SHIFT |
375 SUBCMD_VRAM_SEL << CMDQ_VRAMSEL_SHIFT |
376 (SUBCMD_KEY_TABLE_SEL | ctx->slot->slot_num) <<
377 CMDQ_KEYTABLEID_SHIFT;
378 aes_writel(dd, value, TEGRA_AES_ICMDQUE_WR);
379
380 do {
381 value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
382 eng_busy = value & TEGRA_AES_ENGINE_BUSY_FIELD;
383 icq_empty = value & TEGRA_AES_ICQ_EMPTY_FIELD;
384 } while (eng_busy & (!icq_empty));
385
386 return 0;
387 }
388
tegra_aes_handle_req(struct tegra_aes_dev * dd)389 static int tegra_aes_handle_req(struct tegra_aes_dev *dd)
390 {
391 struct crypto_async_request *async_req, *backlog;
392 struct crypto_ablkcipher *tfm;
393 struct tegra_aes_ctx *ctx;
394 struct tegra_aes_reqctx *rctx;
395 struct ablkcipher_request *req;
396 unsigned long flags;
397 int dma_max = AES_HW_DMA_BUFFER_SIZE_BYTES;
398 int ret = 0, nblocks, total;
399 int count = 0;
400 dma_addr_t addr_in, addr_out;
401 struct scatterlist *in_sg, *out_sg;
402
403 if (!dd)
404 return -EINVAL;
405
406 spin_lock_irqsave(&dd->lock, flags);
407 backlog = crypto_get_backlog(&dd->queue);
408 async_req = crypto_dequeue_request(&dd->queue);
409 if (!async_req)
410 clear_bit(FLAGS_BUSY, &dd->flags);
411 spin_unlock_irqrestore(&dd->lock, flags);
412
413 if (!async_req)
414 return -ENODATA;
415
416 if (backlog)
417 backlog->complete(backlog, -EINPROGRESS);
418
419 req = ablkcipher_request_cast(async_req);
420
421 dev_dbg(dd->dev, "%s: get new req\n", __func__);
422
423 if (!req->src || !req->dst)
424 return -EINVAL;
425
426 /* take mutex to access the aes hw */
427 mutex_lock(&aes_lock);
428
429 /* assign new request to device */
430 dd->req = req;
431 dd->total = req->nbytes;
432 dd->in_offset = 0;
433 dd->in_sg = req->src;
434 dd->out_offset = 0;
435 dd->out_sg = req->dst;
436
437 in_sg = dd->in_sg;
438 out_sg = dd->out_sg;
439
440 total = dd->total;
441
442 tfm = crypto_ablkcipher_reqtfm(req);
443 rctx = ablkcipher_request_ctx(req);
444 ctx = crypto_ablkcipher_ctx(tfm);
445 rctx->mode &= FLAGS_MODE_MASK;
446 dd->flags = (dd->flags & ~FLAGS_MODE_MASK) | rctx->mode;
447
448 dd->iv = (u8 *)req->info;
449 dd->ivlen = crypto_ablkcipher_ivsize(tfm);
450
451 /* assign new context to device */
452 ctx->dd = dd;
453 dd->ctx = ctx;
454
455 if (ctx->flags & FLAGS_NEW_KEY) {
456 /* copy the key */
457 memcpy(dd->ivkey_base, ctx->key, ctx->keylen);
458 memset(dd->ivkey_base + ctx->keylen, 0, AES_HW_KEY_TABLE_LENGTH_BYTES - ctx->keylen);
459 aes_set_key(dd);
460 ctx->flags &= ~FLAGS_NEW_KEY;
461 }
462
463 if (((dd->flags & FLAGS_CBC) || (dd->flags & FLAGS_OFB)) && dd->iv) {
464 /* set iv to the aes hw slot
465 * Hw generates updated iv only after iv is set in slot.
466 * So key and iv is passed asynchronously.
467 */
468 memcpy(dd->buf_in, dd->iv, dd->ivlen);
469
470 ret = aes_start_crypt(dd, (u32)dd->dma_buf_in,
471 dd->dma_buf_out, 1, FLAGS_CBC, false);
472 if (ret < 0) {
473 dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
474 goto out;
475 }
476 }
477
478 while (total) {
479 dev_dbg(dd->dev, "remain: %d\n", total);
480 ret = dma_map_sg(dd->dev, in_sg, 1, DMA_TO_DEVICE);
481 if (!ret) {
482 dev_err(dd->dev, "dma_map_sg() error\n");
483 goto out;
484 }
485
486 ret = dma_map_sg(dd->dev, out_sg, 1, DMA_FROM_DEVICE);
487 if (!ret) {
488 dev_err(dd->dev, "dma_map_sg() error\n");
489 dma_unmap_sg(dd->dev, dd->in_sg,
490 1, DMA_TO_DEVICE);
491 goto out;
492 }
493
494 addr_in = sg_dma_address(in_sg);
495 addr_out = sg_dma_address(out_sg);
496 dd->flags |= FLAGS_FAST;
497 count = min_t(int, sg_dma_len(in_sg), dma_max);
498 WARN_ON(sg_dma_len(in_sg) != sg_dma_len(out_sg));
499 nblocks = DIV_ROUND_UP(count, AES_BLOCK_SIZE);
500
501 ret = aes_start_crypt(dd, addr_in, addr_out, nblocks,
502 dd->flags, true);
503
504 dma_unmap_sg(dd->dev, out_sg, 1, DMA_FROM_DEVICE);
505 dma_unmap_sg(dd->dev, in_sg, 1, DMA_TO_DEVICE);
506
507 if (ret < 0) {
508 dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
509 goto out;
510 }
511 dd->flags &= ~FLAGS_FAST;
512
513 dev_dbg(dd->dev, "out: copied %d\n", count);
514 total -= count;
515 in_sg = sg_next(in_sg);
516 out_sg = sg_next(out_sg);
517 WARN_ON(((total != 0) && (!in_sg || !out_sg)));
518 }
519
520 out:
521 mutex_unlock(&aes_lock);
522
523 dd->total = total;
524
525 if (dd->req->base.complete)
526 dd->req->base.complete(&dd->req->base, ret);
527
528 dev_dbg(dd->dev, "%s: exit\n", __func__);
529 return ret;
530 }
531
tegra_aes_setkey(struct crypto_ablkcipher * tfm,const u8 * key,unsigned int keylen)532 static int tegra_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
533 unsigned int keylen)
534 {
535 struct tegra_aes_ctx *ctx = crypto_ablkcipher_ctx(tfm);
536 struct tegra_aes_dev *dd = aes_dev;
537 struct tegra_aes_slot *key_slot;
538
539 if ((keylen != AES_KEYSIZE_128) && (keylen != AES_KEYSIZE_192) &&
540 (keylen != AES_KEYSIZE_256)) {
541 dev_err(dd->dev, "unsupported key size\n");
542 crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
543 return -EINVAL;
544 }
545
546 dev_dbg(dd->dev, "keylen: %d\n", keylen);
547
548 ctx->dd = dd;
549
550 if (key) {
551 if (!ctx->slot) {
552 key_slot = aes_find_key_slot();
553 if (!key_slot) {
554 dev_err(dd->dev, "no empty slot\n");
555 return -ENOMEM;
556 }
557
558 ctx->slot = key_slot;
559 }
560
561 memcpy(ctx->key, key, keylen);
562 ctx->keylen = keylen;
563 }
564
565 ctx->flags |= FLAGS_NEW_KEY;
566 dev_dbg(dd->dev, "done\n");
567 return 0;
568 }
569
aes_workqueue_handler(struct work_struct * work)570 static void aes_workqueue_handler(struct work_struct *work)
571 {
572 struct tegra_aes_dev *dd = aes_dev;
573 int ret;
574
575 ret = clk_enable(dd->aes_clk);
576 if (ret)
577 BUG_ON("clock enable failed");
578
579 /* empty the crypto queue and then return */
580 do {
581 ret = tegra_aes_handle_req(dd);
582 } while (!ret);
583
584 clk_disable(dd->aes_clk);
585 }
586
aes_irq(int irq,void * dev_id)587 static irqreturn_t aes_irq(int irq, void *dev_id)
588 {
589 struct tegra_aes_dev *dd = (struct tegra_aes_dev *)dev_id;
590 u32 value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
591 int busy = test_bit(FLAGS_BUSY, &dd->flags);
592
593 if (!busy) {
594 dev_dbg(dd->dev, "spurious interrupt\n");
595 return IRQ_NONE;
596 }
597
598 dev_dbg(dd->dev, "irq_stat: 0x%x\n", value);
599 if (value & TEGRA_AES_INT_ERROR_MASK)
600 aes_writel(dd, TEGRA_AES_INT_ERROR_MASK, TEGRA_AES_INTR_STATUS);
601
602 if (!(value & TEGRA_AES_ENGINE_BUSY_FIELD))
603 complete(&dd->op_complete);
604 else
605 return IRQ_NONE;
606
607 return IRQ_HANDLED;
608 }
609
tegra_aes_crypt(struct ablkcipher_request * req,unsigned long mode)610 static int tegra_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
611 {
612 struct tegra_aes_reqctx *rctx = ablkcipher_request_ctx(req);
613 struct tegra_aes_dev *dd = aes_dev;
614 unsigned long flags;
615 int err = 0;
616 int busy;
617
618 dev_dbg(dd->dev, "nbytes: %d, enc: %d, cbc: %d, ofb: %d\n",
619 req->nbytes, !!(mode & FLAGS_ENCRYPT),
620 !!(mode & FLAGS_CBC), !!(mode & FLAGS_OFB));
621
622 rctx->mode = mode;
623
624 spin_lock_irqsave(&dd->lock, flags);
625 err = ablkcipher_enqueue_request(&dd->queue, req);
626 busy = test_and_set_bit(FLAGS_BUSY, &dd->flags);
627 spin_unlock_irqrestore(&dd->lock, flags);
628
629 if (!busy)
630 queue_work(aes_wq, &aes_work);
631
632 return err;
633 }
634
tegra_aes_ecb_encrypt(struct ablkcipher_request * req)635 static int tegra_aes_ecb_encrypt(struct ablkcipher_request *req)
636 {
637 return tegra_aes_crypt(req, FLAGS_ENCRYPT);
638 }
639
tegra_aes_ecb_decrypt(struct ablkcipher_request * req)640 static int tegra_aes_ecb_decrypt(struct ablkcipher_request *req)
641 {
642 return tegra_aes_crypt(req, 0);
643 }
644
tegra_aes_cbc_encrypt(struct ablkcipher_request * req)645 static int tegra_aes_cbc_encrypt(struct ablkcipher_request *req)
646 {
647 return tegra_aes_crypt(req, FLAGS_ENCRYPT | FLAGS_CBC);
648 }
649
tegra_aes_cbc_decrypt(struct ablkcipher_request * req)650 static int tegra_aes_cbc_decrypt(struct ablkcipher_request *req)
651 {
652 return tegra_aes_crypt(req, FLAGS_CBC);
653 }
654
tegra_aes_ofb_encrypt(struct ablkcipher_request * req)655 static int tegra_aes_ofb_encrypt(struct ablkcipher_request *req)
656 {
657 return tegra_aes_crypt(req, FLAGS_ENCRYPT | FLAGS_OFB);
658 }
659
tegra_aes_ofb_decrypt(struct ablkcipher_request * req)660 static int tegra_aes_ofb_decrypt(struct ablkcipher_request *req)
661 {
662 return tegra_aes_crypt(req, FLAGS_OFB);
663 }
664
tegra_aes_get_random(struct crypto_rng * tfm,u8 * rdata,unsigned int dlen)665 static int tegra_aes_get_random(struct crypto_rng *tfm, u8 *rdata,
666 unsigned int dlen)
667 {
668 struct tegra_aes_dev *dd = aes_dev;
669 struct tegra_aes_ctx *ctx = &rng_ctx;
670 int ret, i;
671 u8 *dest = rdata, *dt = dd->dt;
672
673 /* take mutex to access the aes hw */
674 mutex_lock(&aes_lock);
675
676 ret = clk_enable(dd->aes_clk);
677 if (ret)
678 return ret;
679
680 ctx->dd = dd;
681 dd->ctx = ctx;
682 dd->flags = FLAGS_ENCRYPT | FLAGS_RNG;
683
684 memcpy(dd->buf_in, dt, DEFAULT_RNG_BLK_SZ);
685
686 ret = aes_start_crypt(dd, (u32)dd->dma_buf_in,
687 (u32)dd->dma_buf_out, 1, dd->flags, true);
688 if (ret < 0) {
689 dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
690 dlen = ret;
691 goto out;
692 }
693 memcpy(dest, dd->buf_out, dlen);
694
695 /* update the DT */
696 for (i = DEFAULT_RNG_BLK_SZ - 1; i >= 0; i--) {
697 dt[i] += 1;
698 if (dt[i] != 0)
699 break;
700 }
701
702 out:
703 clk_disable(dd->aes_clk);
704 mutex_unlock(&aes_lock);
705
706 dev_dbg(dd->dev, "%s: done\n", __func__);
707 return dlen;
708 }
709
tegra_aes_rng_reset(struct crypto_rng * tfm,u8 * seed,unsigned int slen)710 static int tegra_aes_rng_reset(struct crypto_rng *tfm, u8 *seed,
711 unsigned int slen)
712 {
713 struct tegra_aes_dev *dd = aes_dev;
714 struct tegra_aes_ctx *ctx = &rng_ctx;
715 struct tegra_aes_slot *key_slot;
716 struct timespec ts;
717 int ret = 0;
718 u64 nsec, tmp[2];
719 u8 *dt;
720
721 if (!ctx || !dd) {
722 dev_err(dd->dev, "ctx=0x%x, dd=0x%x\n",
723 (unsigned int)ctx, (unsigned int)dd);
724 return -EINVAL;
725 }
726
727 if (slen < (DEFAULT_RNG_BLK_SZ + AES_KEYSIZE_128)) {
728 dev_err(dd->dev, "seed size invalid");
729 return -ENOMEM;
730 }
731
732 /* take mutex to access the aes hw */
733 mutex_lock(&aes_lock);
734
735 if (!ctx->slot) {
736 key_slot = aes_find_key_slot();
737 if (!key_slot) {
738 dev_err(dd->dev, "no empty slot\n");
739 mutex_unlock(&aes_lock);
740 return -ENOMEM;
741 }
742 ctx->slot = key_slot;
743 }
744
745 ctx->dd = dd;
746 dd->ctx = ctx;
747 dd->ctr = 0;
748
749 ctx->keylen = AES_KEYSIZE_128;
750 ctx->flags |= FLAGS_NEW_KEY;
751
752 /* copy the key to the key slot */
753 memcpy(dd->ivkey_base, seed + DEFAULT_RNG_BLK_SZ, AES_KEYSIZE_128);
754 memset(dd->ivkey_base + AES_KEYSIZE_128, 0, AES_HW_KEY_TABLE_LENGTH_BYTES - AES_KEYSIZE_128);
755
756 dd->iv = seed;
757 dd->ivlen = slen;
758
759 dd->flags = FLAGS_ENCRYPT | FLAGS_RNG;
760
761 ret = clk_enable(dd->aes_clk);
762 if (ret)
763 return ret;
764
765 aes_set_key(dd);
766
767 /* set seed to the aes hw slot */
768 memcpy(dd->buf_in, dd->iv, DEFAULT_RNG_BLK_SZ);
769 ret = aes_start_crypt(dd, (u32)dd->dma_buf_in,
770 dd->dma_buf_out, 1, FLAGS_CBC, false);
771 if (ret < 0) {
772 dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
773 goto out;
774 }
775
776 if (dd->ivlen >= (2 * DEFAULT_RNG_BLK_SZ + AES_KEYSIZE_128)) {
777 dt = dd->iv + DEFAULT_RNG_BLK_SZ + AES_KEYSIZE_128;
778 } else {
779 getnstimeofday(&ts);
780 nsec = timespec_to_ns(&ts);
781 do_div(nsec, 1000);
782 nsec ^= dd->ctr << 56;
783 dd->ctr++;
784 tmp[0] = nsec;
785 tmp[1] = tegra_chip_uid();
786 dt = (u8 *)tmp;
787 }
788 memcpy(dd->dt, dt, DEFAULT_RNG_BLK_SZ);
789
790 out:
791 clk_disable(dd->aes_clk);
792 mutex_unlock(&aes_lock);
793
794 dev_dbg(dd->dev, "%s: done\n", __func__);
795 return ret;
796 }
797
tegra_aes_cra_init(struct crypto_tfm * tfm)798 static int tegra_aes_cra_init(struct crypto_tfm *tfm)
799 {
800 tfm->crt_ablkcipher.reqsize = sizeof(struct tegra_aes_reqctx);
801
802 return 0;
803 }
804
tegra_aes_cra_exit(struct crypto_tfm * tfm)805 void tegra_aes_cra_exit(struct crypto_tfm *tfm)
806 {
807 struct tegra_aes_ctx *ctx =
808 crypto_ablkcipher_ctx((struct crypto_ablkcipher *)tfm);
809
810 if (ctx && ctx->slot)
811 aes_release_key_slot(ctx->slot);
812 }
813
814 static struct crypto_alg algs[] = {
815 {
816 .cra_name = "ecb(aes)",
817 .cra_driver_name = "ecb-aes-tegra",
818 .cra_priority = 300,
819 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
820 .cra_blocksize = AES_BLOCK_SIZE,
821 .cra_alignmask = 3,
822 .cra_type = &crypto_ablkcipher_type,
823 .cra_u.ablkcipher = {
824 .min_keysize = AES_MIN_KEY_SIZE,
825 .max_keysize = AES_MAX_KEY_SIZE,
826 .setkey = tegra_aes_setkey,
827 .encrypt = tegra_aes_ecb_encrypt,
828 .decrypt = tegra_aes_ecb_decrypt,
829 },
830 }, {
831 .cra_name = "cbc(aes)",
832 .cra_driver_name = "cbc-aes-tegra",
833 .cra_priority = 300,
834 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
835 .cra_blocksize = AES_BLOCK_SIZE,
836 .cra_alignmask = 3,
837 .cra_type = &crypto_ablkcipher_type,
838 .cra_u.ablkcipher = {
839 .min_keysize = AES_MIN_KEY_SIZE,
840 .max_keysize = AES_MAX_KEY_SIZE,
841 .ivsize = AES_MIN_KEY_SIZE,
842 .setkey = tegra_aes_setkey,
843 .encrypt = tegra_aes_cbc_encrypt,
844 .decrypt = tegra_aes_cbc_decrypt,
845 }
846 }, {
847 .cra_name = "ofb(aes)",
848 .cra_driver_name = "ofb-aes-tegra",
849 .cra_priority = 300,
850 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
851 .cra_blocksize = AES_BLOCK_SIZE,
852 .cra_alignmask = 3,
853 .cra_type = &crypto_ablkcipher_type,
854 .cra_u.ablkcipher = {
855 .min_keysize = AES_MIN_KEY_SIZE,
856 .max_keysize = AES_MAX_KEY_SIZE,
857 .ivsize = AES_MIN_KEY_SIZE,
858 .setkey = tegra_aes_setkey,
859 .encrypt = tegra_aes_ofb_encrypt,
860 .decrypt = tegra_aes_ofb_decrypt,
861 }
862 }, {
863 .cra_name = "ansi_cprng",
864 .cra_driver_name = "rng-aes-tegra",
865 .cra_flags = CRYPTO_ALG_TYPE_RNG,
866 .cra_ctxsize = sizeof(struct tegra_aes_ctx),
867 .cra_type = &crypto_rng_type,
868 .cra_u.rng = {
869 .rng_make_random = tegra_aes_get_random,
870 .rng_reset = tegra_aes_rng_reset,
871 .seedsize = AES_KEYSIZE_128 + (2 * DEFAULT_RNG_BLK_SZ),
872 }
873 }
874 };
875
tegra_aes_probe(struct platform_device * pdev)876 static int tegra_aes_probe(struct platform_device *pdev)
877 {
878 struct device *dev = &pdev->dev;
879 struct tegra_aes_dev *dd;
880 struct resource *res;
881 int err = -ENOMEM, i = 0, j;
882
883 dd = devm_kzalloc(dev, sizeof(struct tegra_aes_dev), GFP_KERNEL);
884 if (dd == NULL) {
885 dev_err(dev, "unable to alloc data struct.\n");
886 return err;
887 }
888
889 dd->dev = dev;
890 platform_set_drvdata(pdev, dd);
891
892 dd->slots = devm_kzalloc(dev, sizeof(struct tegra_aes_slot) *
893 AES_NR_KEYSLOTS, GFP_KERNEL);
894 if (dd->slots == NULL) {
895 dev_err(dev, "unable to alloc slot struct.\n");
896 goto out;
897 }
898
899 spin_lock_init(&dd->lock);
900 crypto_init_queue(&dd->queue, TEGRA_AES_QUEUE_LENGTH);
901
902 /* Get the module base address */
903 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
904 if (!res) {
905 dev_err(dev, "invalid resource type: base\n");
906 err = -ENODEV;
907 goto out;
908 }
909
910 if (!devm_request_mem_region(&pdev->dev, res->start,
911 resource_size(res),
912 dev_name(&pdev->dev))) {
913 dev_err(&pdev->dev, "Couldn't request MEM resource\n");
914 return -ENODEV;
915 }
916
917 dd->io_base = devm_ioremap(dev, res->start, resource_size(res));
918 if (!dd->io_base) {
919 dev_err(dev, "can't ioremap register space\n");
920 err = -ENOMEM;
921 goto out;
922 }
923
924 /* Initialize the vde clock */
925 dd->aes_clk = clk_get(dev, "vde");
926 if (IS_ERR(dd->aes_clk)) {
927 dev_err(dev, "iclock intialization failed.\n");
928 err = -ENODEV;
929 goto out;
930 }
931
932 err = clk_set_rate(dd->aes_clk, ULONG_MAX);
933 if (err) {
934 dev_err(dd->dev, "iclk set_rate fail(%d)\n", err);
935 goto out;
936 }
937
938 /*
939 * the foll contiguous memory is allocated as follows -
940 * - hardware key table
941 * - key schedule
942 */
943 dd->ivkey_base = dma_alloc_coherent(dev, AES_HW_KEY_TABLE_LENGTH_BYTES,
944 &dd->ivkey_phys_base,
945 GFP_KERNEL);
946 if (!dd->ivkey_base) {
947 dev_err(dev, "can not allocate iv/key buffer\n");
948 err = -ENOMEM;
949 goto out;
950 }
951
952 dd->buf_in = dma_alloc_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
953 &dd->dma_buf_in, GFP_KERNEL);
954 if (!dd->buf_in) {
955 dev_err(dev, "can not allocate dma-in buffer\n");
956 err = -ENOMEM;
957 goto out;
958 }
959
960 dd->buf_out = dma_alloc_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
961 &dd->dma_buf_out, GFP_KERNEL);
962 if (!dd->buf_out) {
963 dev_err(dev, "can not allocate dma-out buffer\n");
964 err = -ENOMEM;
965 goto out;
966 }
967
968 init_completion(&dd->op_complete);
969 aes_wq = alloc_workqueue("tegra_aes_wq", WQ_HIGHPRI | WQ_UNBOUND, 1);
970 if (!aes_wq) {
971 dev_err(dev, "alloc_workqueue failed\n");
972 goto out;
973 }
974
975 /* get the irq */
976 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
977 if (!res) {
978 dev_err(dev, "invalid resource type: base\n");
979 err = -ENODEV;
980 goto out;
981 }
982 dd->irq = res->start;
983
984 err = devm_request_irq(dev, dd->irq, aes_irq, IRQF_TRIGGER_HIGH |
985 IRQF_SHARED, "tegra-aes", dd);
986 if (err) {
987 dev_err(dev, "request_irq failed\n");
988 goto out;
989 }
990
991 mutex_init(&aes_lock);
992 INIT_LIST_HEAD(&dev_list);
993
994 spin_lock_init(&list_lock);
995 spin_lock(&list_lock);
996 for (i = 0; i < AES_NR_KEYSLOTS; i++) {
997 if (i == SSK_SLOT_NUM)
998 continue;
999 dd->slots[i].slot_num = i;
1000 INIT_LIST_HEAD(&dd->slots[i].node);
1001 list_add_tail(&dd->slots[i].node, &dev_list);
1002 }
1003 spin_unlock(&list_lock);
1004
1005 aes_dev = dd;
1006 for (i = 0; i < ARRAY_SIZE(algs); i++) {
1007 INIT_LIST_HEAD(&algs[i].cra_list);
1008
1009 algs[i].cra_priority = 300;
1010 algs[i].cra_ctxsize = sizeof(struct tegra_aes_ctx);
1011 algs[i].cra_module = THIS_MODULE;
1012 algs[i].cra_init = tegra_aes_cra_init;
1013 algs[i].cra_exit = tegra_aes_cra_exit;
1014
1015 err = crypto_register_alg(&algs[i]);
1016 if (err)
1017 goto out;
1018 }
1019
1020 dev_info(dev, "registered");
1021 return 0;
1022
1023 out:
1024 for (j = 0; j < i; j++)
1025 crypto_unregister_alg(&algs[j]);
1026 if (dd->ivkey_base)
1027 dma_free_coherent(dev, AES_HW_KEY_TABLE_LENGTH_BYTES,
1028 dd->ivkey_base, dd->ivkey_phys_base);
1029 if (dd->buf_in)
1030 dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
1031 dd->buf_in, dd->dma_buf_in);
1032 if (dd->buf_out)
1033 dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
1034 dd->buf_out, dd->dma_buf_out);
1035 if (IS_ERR(dd->aes_clk))
1036 clk_put(dd->aes_clk);
1037 if (aes_wq)
1038 destroy_workqueue(aes_wq);
1039 spin_lock(&list_lock);
1040 list_del(&dev_list);
1041 spin_unlock(&list_lock);
1042
1043 aes_dev = NULL;
1044
1045 dev_err(dev, "%s: initialization failed.\n", __func__);
1046 return err;
1047 }
1048
tegra_aes_remove(struct platform_device * pdev)1049 static int __devexit tegra_aes_remove(struct platform_device *pdev)
1050 {
1051 struct device *dev = &pdev->dev;
1052 struct tegra_aes_dev *dd = platform_get_drvdata(pdev);
1053 int i;
1054
1055 for (i = 0; i < ARRAY_SIZE(algs); i++)
1056 crypto_unregister_alg(&algs[i]);
1057
1058 cancel_work_sync(&aes_work);
1059 destroy_workqueue(aes_wq);
1060 spin_lock(&list_lock);
1061 list_del(&dev_list);
1062 spin_unlock(&list_lock);
1063
1064 dma_free_coherent(dev, AES_HW_KEY_TABLE_LENGTH_BYTES,
1065 dd->ivkey_base, dd->ivkey_phys_base);
1066 dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
1067 dd->buf_in, dd->dma_buf_in);
1068 dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
1069 dd->buf_out, dd->dma_buf_out);
1070 clk_put(dd->aes_clk);
1071 aes_dev = NULL;
1072
1073 return 0;
1074 }
1075
1076 static struct of_device_id tegra_aes_of_match[] __devinitdata = {
1077 { .compatible = "nvidia,tegra20-aes", },
1078 { .compatible = "nvidia,tegra30-aes", },
1079 { },
1080 };
1081
1082 static struct platform_driver tegra_aes_driver = {
1083 .probe = tegra_aes_probe,
1084 .remove = __devexit_p(tegra_aes_remove),
1085 .driver = {
1086 .name = "tegra-aes",
1087 .owner = THIS_MODULE,
1088 .of_match_table = tegra_aes_of_match,
1089 },
1090 };
1091
1092 module_platform_driver(tegra_aes_driver);
1093
1094 MODULE_DESCRIPTION("Tegra AES/OFB/CPRNG hw acceleration support.");
1095 MODULE_AUTHOR("NVIDIA Corporation");
1096 MODULE_LICENSE("GPL v2");
1097