blob: 060eecc5dbc31b24bf0c05301b37192da7e36dff [file] [log] [blame]
Varun Wadekarf1df57d2012-01-13 16:38:37 +11001/*
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
Sachin Kamat6665ad22013-09-16 09:01:10 +053030#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
31
Varun Wadekarf1df57d2012-01-13 16:38:37 +110032#include <linux/module.h>
33#include <linux/init.h>
34#include <linux/errno.h>
35#include <linux/kernel.h>
36#include <linux/clk.h>
37#include <linux/platform_device.h>
38#include <linux/scatterlist.h>
39#include <linux/dma-mapping.h>
40#include <linux/io.h>
41#include <linux/mutex.h>
42#include <linux/interrupt.h>
43#include <linux/completion.h>
44#include <linux/workqueue.h>
45
Varun Wadekarf1df57d2012-01-13 16:38:37 +110046#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 */
94enum {
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 */
103enum {
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 */
116enum {
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
138struct tegra_aes_slot {
139 struct list_head node;
140 int slot_num;
141};
142
143static struct tegra_aes_slot ssk = {
144 .slot_num = SSK_SLOT_NUM,
145};
146
147struct tegra_aes_reqctx {
148 unsigned long mode;
149};
150
151struct 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
180static struct tegra_aes_dev *aes_dev;
181
182struct 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
190static struct tegra_aes_ctx rng_ctx = {
191 .flags = FLAGS_NEW_KEY,
192 .keylen = AES_KEYSIZE_128,
193};
194
195/* keep registered devices data here */
196static struct list_head dev_list;
197static DEFINE_SPINLOCK(list_lock);
198static DEFINE_MUTEX(aes_lock);
199
200static void aes_workqueue_handler(struct work_struct *work);
201static DECLARE_WORK(aes_work, aes_workqueue_handler);
202static struct workqueue_struct *aes_wq;
203
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100204static inline u32 aes_readl(struct tegra_aes_dev *dd, u32 offset)
205{
206 return readl(dd->io_base + offset);
207}
208
209static inline void aes_writel(struct tegra_aes_dev *dd, u32 val, u32 offset)
210{
211 writel(val, dd->io_base + offset);
212}
213
214static int aes_start_crypt(struct tegra_aes_dev *dd, u32 in_addr, u32 out_addr,
215 int nblocks, int mode, bool upd_iv)
216{
217 u32 cmdq[AES_HW_MAX_ICQ_LENGTH];
218 int i, eng_busy, icq_empty, ret;
219 u32 value;
220
221 /* reset all the interrupt bits */
222 aes_writel(dd, 0xFFFFFFFF, TEGRA_AES_INTR_STATUS);
223
224 /* enable error, dma xfer complete interrupts */
225 aes_writel(dd, 0x33, TEGRA_AES_INT_ENB);
226
227 cmdq[0] = CMD_DMASETUP << CMDQ_OPCODE_SHIFT;
228 cmdq[1] = in_addr;
229 cmdq[2] = CMD_BLKSTARTENGINE << CMDQ_OPCODE_SHIFT | (nblocks-1);
230 cmdq[3] = CMD_DMACOMPLETE << CMDQ_OPCODE_SHIFT;
231
232 value = aes_readl(dd, TEGRA_AES_CMDQUE_CONTROL);
233 /* access SDRAM through AHB */
234 value &= ~TEGRA_AES_CMDQ_CTRL_SRC_STM_SEL_FIELD;
235 value &= ~TEGRA_AES_CMDQ_CTRL_DST_STM_SEL_FIELD;
236 value |= TEGRA_AES_CMDQ_CTRL_SRC_STM_SEL_FIELD |
237 TEGRA_AES_CMDQ_CTRL_DST_STM_SEL_FIELD |
238 TEGRA_AES_CMDQ_CTRL_ICMDQEN_FIELD;
239 aes_writel(dd, value, TEGRA_AES_CMDQUE_CONTROL);
240 dev_dbg(dd->dev, "cmd_q_ctrl=0x%x", value);
241
242 value = (0x1 << TEGRA_AES_SECURE_INPUT_ALG_SEL_SHIFT) |
243 ((dd->ctx->keylen * 8) <<
244 TEGRA_AES_SECURE_INPUT_KEY_LEN_SHIFT) |
245 ((u32)upd_iv << TEGRA_AES_SECURE_IV_SELECT_SHIFT);
246
247 if (mode & FLAGS_CBC) {
248 value |= ((((mode & FLAGS_ENCRYPT) ? 2 : 3)
249 << TEGRA_AES_SECURE_XOR_POS_SHIFT) |
250 (((mode & FLAGS_ENCRYPT) ? 2 : 3)
251 << TEGRA_AES_SECURE_VCTRAM_SEL_SHIFT) |
252 ((mode & FLAGS_ENCRYPT) ? 1 : 0)
253 << TEGRA_AES_SECURE_CORE_SEL_SHIFT);
254 } else if (mode & FLAGS_OFB) {
255 value |= ((TEGRA_AES_SECURE_XOR_POS_FIELD) |
256 (2 << TEGRA_AES_SECURE_INPUT_SEL_SHIFT) |
257 (TEGRA_AES_SECURE_CORE_SEL_FIELD));
258 } else if (mode & FLAGS_RNG) {
259 value |= (((mode & FLAGS_ENCRYPT) ? 1 : 0)
260 << TEGRA_AES_SECURE_CORE_SEL_SHIFT |
261 TEGRA_AES_SECURE_RNG_ENB_FIELD);
262 } else {
263 value |= (((mode & FLAGS_ENCRYPT) ? 1 : 0)
264 << TEGRA_AES_SECURE_CORE_SEL_SHIFT);
265 }
266
267 dev_dbg(dd->dev, "secure_in_sel=0x%x", value);
268 aes_writel(dd, value, TEGRA_AES_SECURE_INPUT_SELECT);
269
270 aes_writel(dd, out_addr, TEGRA_AES_SECURE_DEST_ADDR);
Wolfram Sang16735d02013-11-14 14:32:02 -0800271 reinit_completion(&dd->op_complete);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100272
273 for (i = 0; i < AES_HW_MAX_ICQ_LENGTH - 1; i++) {
274 do {
275 value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
276 eng_busy = value & TEGRA_AES_ENGINE_BUSY_FIELD;
277 icq_empty = value & TEGRA_AES_ICQ_EMPTY_FIELD;
Dan Carpenter5bc35702013-08-20 11:54:48 +0300278 } while (eng_busy && !icq_empty);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100279 aes_writel(dd, cmdq[i], TEGRA_AES_ICMDQUE_WR);
280 }
281
282 ret = wait_for_completion_timeout(&dd->op_complete,
283 msecs_to_jiffies(150));
284 if (ret == 0) {
285 dev_err(dd->dev, "timed out (0x%x)\n",
286 aes_readl(dd, TEGRA_AES_INTR_STATUS));
287 return -ETIMEDOUT;
288 }
289
290 aes_writel(dd, cmdq[AES_HW_MAX_ICQ_LENGTH - 1], TEGRA_AES_ICMDQUE_WR);
291 return 0;
292}
293
294static void aes_release_key_slot(struct tegra_aes_slot *slot)
295{
296 if (slot->slot_num == SSK_SLOT_NUM)
297 return;
298
299 spin_lock(&list_lock);
300 list_add_tail(&slot->node, &dev_list);
301 slot = NULL;
302 spin_unlock(&list_lock);
303}
304
305static struct tegra_aes_slot *aes_find_key_slot(void)
306{
307 struct tegra_aes_slot *slot = NULL;
308 struct list_head *new_head;
309 int empty;
310
311 spin_lock(&list_lock);
312 empty = list_empty(&dev_list);
313 if (!empty) {
314 slot = list_entry(&dev_list, struct tegra_aes_slot, node);
315 new_head = dev_list.next;
316 list_del(&dev_list);
317 dev_list.next = new_head->next;
318 dev_list.prev = NULL;
319 }
320 spin_unlock(&list_lock);
321
322 return slot;
323}
324
325static int aes_set_key(struct tegra_aes_dev *dd)
326{
327 u32 value, cmdq[2];
328 struct tegra_aes_ctx *ctx = dd->ctx;
329 int eng_busy, icq_empty, dma_busy;
330 bool use_ssk = false;
331
332 /* use ssk? */
333 if (!dd->ctx->slot) {
334 dev_dbg(dd->dev, "using ssk");
335 dd->ctx->slot = &ssk;
336 use_ssk = true;
337 }
338
339 /* enable key schedule generation in hardware */
340 value = aes_readl(dd, TEGRA_AES_SECURE_CONFIG_EXT);
341 value &= ~TEGRA_AES_SECURE_KEY_SCH_DIS_FIELD;
342 aes_writel(dd, value, TEGRA_AES_SECURE_CONFIG_EXT);
343
344 /* select the key slot */
345 value = aes_readl(dd, TEGRA_AES_SECURE_CONFIG);
346 value &= ~TEGRA_AES_SECURE_KEY_INDEX_FIELD;
347 value |= (ctx->slot->slot_num << TEGRA_AES_SECURE_KEY_INDEX_SHIFT);
348 aes_writel(dd, value, TEGRA_AES_SECURE_CONFIG);
349
350 if (use_ssk)
351 return 0;
352
353 /* copy the key table from sdram to vram */
354 cmdq[0] = CMD_MEMDMAVD << CMDQ_OPCODE_SHIFT |
355 MEMDMA_DIR_DTOVRAM << MEMDMA_DIR_SHIFT |
356 AES_HW_KEY_TABLE_LENGTH_BYTES / sizeof(u32) <<
357 MEMDMA_NUM_WORDS_SHIFT;
358 cmdq[1] = (u32)dd->ivkey_phys_base;
359
360 aes_writel(dd, cmdq[0], TEGRA_AES_ICMDQUE_WR);
361 aes_writel(dd, cmdq[1], TEGRA_AES_ICMDQUE_WR);
362
363 do {
364 value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
365 eng_busy = value & TEGRA_AES_ENGINE_BUSY_FIELD;
366 icq_empty = value & TEGRA_AES_ICQ_EMPTY_FIELD;
367 dma_busy = value & TEGRA_AES_DMA_BUSY_FIELD;
Dan Carpenter5bc35702013-08-20 11:54:48 +0300368 } while (eng_busy && !icq_empty && dma_busy);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100369
370 /* settable command to get key into internal registers */
371 value = CMD_SETTABLE << CMDQ_OPCODE_SHIFT |
372 SUBCMD_CRYPTO_TABLE_SEL << CMDQ_TABLESEL_SHIFT |
373 SUBCMD_VRAM_SEL << CMDQ_VRAMSEL_SHIFT |
374 (SUBCMD_KEY_TABLE_SEL | ctx->slot->slot_num) <<
375 CMDQ_KEYTABLEID_SHIFT;
376 aes_writel(dd, value, TEGRA_AES_ICMDQUE_WR);
377
378 do {
379 value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
380 eng_busy = value & TEGRA_AES_ENGINE_BUSY_FIELD;
381 icq_empty = value & TEGRA_AES_ICQ_EMPTY_FIELD;
Dan Carpenter5bc35702013-08-20 11:54:48 +0300382 } while (eng_busy && !icq_empty);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100383
384 return 0;
385}
386
387static int tegra_aes_handle_req(struct tegra_aes_dev *dd)
388{
389 struct crypto_async_request *async_req, *backlog;
390 struct crypto_ablkcipher *tfm;
391 struct tegra_aes_ctx *ctx;
392 struct tegra_aes_reqctx *rctx;
393 struct ablkcipher_request *req;
394 unsigned long flags;
395 int dma_max = AES_HW_DMA_BUFFER_SIZE_BYTES;
396 int ret = 0, nblocks, total;
397 int count = 0;
398 dma_addr_t addr_in, addr_out;
399 struct scatterlist *in_sg, *out_sg;
400
401 if (!dd)
402 return -EINVAL;
403
404 spin_lock_irqsave(&dd->lock, flags);
405 backlog = crypto_get_backlog(&dd->queue);
406 async_req = crypto_dequeue_request(&dd->queue);
407 if (!async_req)
408 clear_bit(FLAGS_BUSY, &dd->flags);
409 spin_unlock_irqrestore(&dd->lock, flags);
410
411 if (!async_req)
412 return -ENODATA;
413
414 if (backlog)
415 backlog->complete(backlog, -EINPROGRESS);
416
417 req = ablkcipher_request_cast(async_req);
418
419 dev_dbg(dd->dev, "%s: get new req\n", __func__);
420
421 if (!req->src || !req->dst)
422 return -EINVAL;
423
424 /* take mutex to access the aes hw */
425 mutex_lock(&aes_lock);
426
427 /* assign new request to device */
428 dd->req = req;
429 dd->total = req->nbytes;
430 dd->in_offset = 0;
431 dd->in_sg = req->src;
432 dd->out_offset = 0;
433 dd->out_sg = req->dst;
434
435 in_sg = dd->in_sg;
436 out_sg = dd->out_sg;
437
438 total = dd->total;
439
440 tfm = crypto_ablkcipher_reqtfm(req);
441 rctx = ablkcipher_request_ctx(req);
442 ctx = crypto_ablkcipher_ctx(tfm);
443 rctx->mode &= FLAGS_MODE_MASK;
444 dd->flags = (dd->flags & ~FLAGS_MODE_MASK) | rctx->mode;
445
446 dd->iv = (u8 *)req->info;
447 dd->ivlen = crypto_ablkcipher_ivsize(tfm);
448
449 /* assign new context to device */
450 ctx->dd = dd;
451 dd->ctx = ctx;
452
453 if (ctx->flags & FLAGS_NEW_KEY) {
454 /* copy the key */
455 memcpy(dd->ivkey_base, ctx->key, ctx->keylen);
456 memset(dd->ivkey_base + ctx->keylen, 0, AES_HW_KEY_TABLE_LENGTH_BYTES - ctx->keylen);
457 aes_set_key(dd);
458 ctx->flags &= ~FLAGS_NEW_KEY;
459 }
460
461 if (((dd->flags & FLAGS_CBC) || (dd->flags & FLAGS_OFB)) && dd->iv) {
462 /* set iv to the aes hw slot
463 * Hw generates updated iv only after iv is set in slot.
464 * So key and iv is passed asynchronously.
465 */
466 memcpy(dd->buf_in, dd->iv, dd->ivlen);
467
468 ret = aes_start_crypt(dd, (u32)dd->dma_buf_in,
469 dd->dma_buf_out, 1, FLAGS_CBC, false);
470 if (ret < 0) {
471 dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
472 goto out;
473 }
474 }
475
476 while (total) {
477 dev_dbg(dd->dev, "remain: %d\n", total);
478 ret = dma_map_sg(dd->dev, in_sg, 1, DMA_TO_DEVICE);
479 if (!ret) {
480 dev_err(dd->dev, "dma_map_sg() error\n");
481 goto out;
482 }
483
484 ret = dma_map_sg(dd->dev, out_sg, 1, DMA_FROM_DEVICE);
485 if (!ret) {
486 dev_err(dd->dev, "dma_map_sg() error\n");
487 dma_unmap_sg(dd->dev, dd->in_sg,
488 1, DMA_TO_DEVICE);
489 goto out;
490 }
491
492 addr_in = sg_dma_address(in_sg);
493 addr_out = sg_dma_address(out_sg);
494 dd->flags |= FLAGS_FAST;
495 count = min_t(int, sg_dma_len(in_sg), dma_max);
496 WARN_ON(sg_dma_len(in_sg) != sg_dma_len(out_sg));
497 nblocks = DIV_ROUND_UP(count, AES_BLOCK_SIZE);
498
499 ret = aes_start_crypt(dd, addr_in, addr_out, nblocks,
500 dd->flags, true);
501
502 dma_unmap_sg(dd->dev, out_sg, 1, DMA_FROM_DEVICE);
503 dma_unmap_sg(dd->dev, in_sg, 1, DMA_TO_DEVICE);
504
505 if (ret < 0) {
506 dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
507 goto out;
508 }
509 dd->flags &= ~FLAGS_FAST;
510
511 dev_dbg(dd->dev, "out: copied %d\n", count);
512 total -= count;
513 in_sg = sg_next(in_sg);
514 out_sg = sg_next(out_sg);
515 WARN_ON(((total != 0) && (!in_sg || !out_sg)));
516 }
517
518out:
519 mutex_unlock(&aes_lock);
520
521 dd->total = total;
522
523 if (dd->req->base.complete)
524 dd->req->base.complete(&dd->req->base, ret);
525
526 dev_dbg(dd->dev, "%s: exit\n", __func__);
527 return ret;
528}
529
530static int tegra_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
531 unsigned int keylen)
532{
533 struct tegra_aes_ctx *ctx = crypto_ablkcipher_ctx(tfm);
534 struct tegra_aes_dev *dd = aes_dev;
535 struct tegra_aes_slot *key_slot;
536
537 if ((keylen != AES_KEYSIZE_128) && (keylen != AES_KEYSIZE_192) &&
538 (keylen != AES_KEYSIZE_256)) {
539 dev_err(dd->dev, "unsupported key size\n");
540 crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
541 return -EINVAL;
542 }
543
544 dev_dbg(dd->dev, "keylen: %d\n", keylen);
545
546 ctx->dd = dd;
547
548 if (key) {
549 if (!ctx->slot) {
550 key_slot = aes_find_key_slot();
551 if (!key_slot) {
552 dev_err(dd->dev, "no empty slot\n");
553 return -ENOMEM;
554 }
555
556 ctx->slot = key_slot;
557 }
558
559 memcpy(ctx->key, key, keylen);
560 ctx->keylen = keylen;
561 }
562
563 ctx->flags |= FLAGS_NEW_KEY;
564 dev_dbg(dd->dev, "done\n");
565 return 0;
566}
567
568static void aes_workqueue_handler(struct work_struct *work)
569{
570 struct tegra_aes_dev *dd = aes_dev;
571 int ret;
572
Prashant Gaikwad0df1ed42012-06-05 09:59:43 +0530573 ret = clk_prepare_enable(dd->aes_clk);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100574 if (ret)
575 BUG_ON("clock enable failed");
576
577 /* empty the crypto queue and then return */
578 do {
579 ret = tegra_aes_handle_req(dd);
580 } while (!ret);
581
Prashant Gaikwad0df1ed42012-06-05 09:59:43 +0530582 clk_disable_unprepare(dd->aes_clk);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100583}
584
585static irqreturn_t aes_irq(int irq, void *dev_id)
586{
587 struct tegra_aes_dev *dd = (struct tegra_aes_dev *)dev_id;
588 u32 value = aes_readl(dd, TEGRA_AES_INTR_STATUS);
589 int busy = test_bit(FLAGS_BUSY, &dd->flags);
590
591 if (!busy) {
592 dev_dbg(dd->dev, "spurious interrupt\n");
593 return IRQ_NONE;
594 }
595
596 dev_dbg(dd->dev, "irq_stat: 0x%x\n", value);
597 if (value & TEGRA_AES_INT_ERROR_MASK)
598 aes_writel(dd, TEGRA_AES_INT_ERROR_MASK, TEGRA_AES_INTR_STATUS);
599
600 if (!(value & TEGRA_AES_ENGINE_BUSY_FIELD))
601 complete(&dd->op_complete);
602 else
603 return IRQ_NONE;
604
605 return IRQ_HANDLED;
606}
607
608static int tegra_aes_crypt(struct ablkcipher_request *req, unsigned long mode)
609{
610 struct tegra_aes_reqctx *rctx = ablkcipher_request_ctx(req);
611 struct tegra_aes_dev *dd = aes_dev;
612 unsigned long flags;
613 int err = 0;
614 int busy;
615
616 dev_dbg(dd->dev, "nbytes: %d, enc: %d, cbc: %d, ofb: %d\n",
617 req->nbytes, !!(mode & FLAGS_ENCRYPT),
618 !!(mode & FLAGS_CBC), !!(mode & FLAGS_OFB));
619
620 rctx->mode = mode;
621
622 spin_lock_irqsave(&dd->lock, flags);
623 err = ablkcipher_enqueue_request(&dd->queue, req);
624 busy = test_and_set_bit(FLAGS_BUSY, &dd->flags);
625 spin_unlock_irqrestore(&dd->lock, flags);
626
627 if (!busy)
628 queue_work(aes_wq, &aes_work);
629
630 return err;
631}
632
633static int tegra_aes_ecb_encrypt(struct ablkcipher_request *req)
634{
635 return tegra_aes_crypt(req, FLAGS_ENCRYPT);
636}
637
638static int tegra_aes_ecb_decrypt(struct ablkcipher_request *req)
639{
640 return tegra_aes_crypt(req, 0);
641}
642
643static int tegra_aes_cbc_encrypt(struct ablkcipher_request *req)
644{
645 return tegra_aes_crypt(req, FLAGS_ENCRYPT | FLAGS_CBC);
646}
647
648static int tegra_aes_cbc_decrypt(struct ablkcipher_request *req)
649{
650 return tegra_aes_crypt(req, FLAGS_CBC);
651}
652
653static int tegra_aes_ofb_encrypt(struct ablkcipher_request *req)
654{
655 return tegra_aes_crypt(req, FLAGS_ENCRYPT | FLAGS_OFB);
656}
657
658static int tegra_aes_ofb_decrypt(struct ablkcipher_request *req)
659{
660 return tegra_aes_crypt(req, FLAGS_OFB);
661}
662
663static int tegra_aes_get_random(struct crypto_rng *tfm, u8 *rdata,
664 unsigned int dlen)
665{
666 struct tegra_aes_dev *dd = aes_dev;
667 struct tegra_aes_ctx *ctx = &rng_ctx;
668 int ret, i;
669 u8 *dest = rdata, *dt = dd->dt;
670
671 /* take mutex to access the aes hw */
672 mutex_lock(&aes_lock);
673
Prashant Gaikwad0df1ed42012-06-05 09:59:43 +0530674 ret = clk_prepare_enable(dd->aes_clk);
Wei Yongjun3200da82012-10-21 19:56:42 +0800675 if (ret) {
676 mutex_unlock(&aes_lock);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100677 return ret;
Wei Yongjun3200da82012-10-21 19:56:42 +0800678 }
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100679
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
702out:
Prashant Gaikwad0df1ed42012-06-05 09:59:43 +0530703 clk_disable_unprepare(dd->aes_clk);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100704 mutex_unlock(&aes_lock);
705
706 dev_dbg(dd->dev, "%s: done\n", __func__);
707 return dlen;
708}
709
710static 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;
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100716 int ret = 0;
Linus Walleijf5b38c52013-09-09 09:35:54 +0200717 u8 tmp[16]; /* 16 bytes = 128 bits of entropy */
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100718 u8 *dt;
719
720 if (!ctx || !dd) {
Sachin Kamat6665ad22013-09-16 09:01:10 +0530721 pr_err("ctx=0x%x, dd=0x%x\n",
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100722 (unsigned int)ctx, (unsigned int)dd);
723 return -EINVAL;
724 }
725
726 if (slen < (DEFAULT_RNG_BLK_SZ + AES_KEYSIZE_128)) {
727 dev_err(dd->dev, "seed size invalid");
728 return -ENOMEM;
729 }
730
731 /* take mutex to access the aes hw */
732 mutex_lock(&aes_lock);
733
734 if (!ctx->slot) {
735 key_slot = aes_find_key_slot();
736 if (!key_slot) {
737 dev_err(dd->dev, "no empty slot\n");
738 mutex_unlock(&aes_lock);
739 return -ENOMEM;
740 }
741 ctx->slot = key_slot;
742 }
743
744 ctx->dd = dd;
745 dd->ctx = ctx;
746 dd->ctr = 0;
747
748 ctx->keylen = AES_KEYSIZE_128;
749 ctx->flags |= FLAGS_NEW_KEY;
750
751 /* copy the key to the key slot */
752 memcpy(dd->ivkey_base, seed + DEFAULT_RNG_BLK_SZ, AES_KEYSIZE_128);
753 memset(dd->ivkey_base + AES_KEYSIZE_128, 0, AES_HW_KEY_TABLE_LENGTH_BYTES - AES_KEYSIZE_128);
754
755 dd->iv = seed;
756 dd->ivlen = slen;
757
758 dd->flags = FLAGS_ENCRYPT | FLAGS_RNG;
759
Prashant Gaikwad0df1ed42012-06-05 09:59:43 +0530760 ret = clk_prepare_enable(dd->aes_clk);
Wei Yongjun3200da82012-10-21 19:56:42 +0800761 if (ret) {
762 mutex_unlock(&aes_lock);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100763 return ret;
Wei Yongjun3200da82012-10-21 19:56:42 +0800764 }
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100765
766 aes_set_key(dd);
767
768 /* set seed to the aes hw slot */
769 memcpy(dd->buf_in, dd->iv, DEFAULT_RNG_BLK_SZ);
770 ret = aes_start_crypt(dd, (u32)dd->dma_buf_in,
771 dd->dma_buf_out, 1, FLAGS_CBC, false);
772 if (ret < 0) {
773 dev_err(dd->dev, "aes_start_crypt fail(%d)\n", ret);
774 goto out;
775 }
776
777 if (dd->ivlen >= (2 * DEFAULT_RNG_BLK_SZ + AES_KEYSIZE_128)) {
778 dt = dd->iv + DEFAULT_RNG_BLK_SZ + AES_KEYSIZE_128;
779 } else {
Linus Walleijf5b38c52013-09-09 09:35:54 +0200780 get_random_bytes(tmp, sizeof(tmp));
781 dt = tmp;
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100782 }
783 memcpy(dd->dt, dt, DEFAULT_RNG_BLK_SZ);
784
785out:
Prashant Gaikwad0df1ed42012-06-05 09:59:43 +0530786 clk_disable_unprepare(dd->aes_clk);
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100787 mutex_unlock(&aes_lock);
788
789 dev_dbg(dd->dev, "%s: done\n", __func__);
790 return ret;
791}
792
793static int tegra_aes_cra_init(struct crypto_tfm *tfm)
794{
795 tfm->crt_ablkcipher.reqsize = sizeof(struct tegra_aes_reqctx);
796
797 return 0;
798}
799
Sachin Kamat4903e962013-09-13 17:06:47 +0530800static void tegra_aes_cra_exit(struct crypto_tfm *tfm)
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100801{
802 struct tegra_aes_ctx *ctx =
803 crypto_ablkcipher_ctx((struct crypto_ablkcipher *)tfm);
804
805 if (ctx && ctx->slot)
806 aes_release_key_slot(ctx->slot);
807}
808
809static struct crypto_alg algs[] = {
810 {
811 .cra_name = "ecb(aes)",
812 .cra_driver_name = "ecb-aes-tegra",
813 .cra_priority = 300,
814 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
815 .cra_blocksize = AES_BLOCK_SIZE,
816 .cra_alignmask = 3,
817 .cra_type = &crypto_ablkcipher_type,
818 .cra_u.ablkcipher = {
819 .min_keysize = AES_MIN_KEY_SIZE,
820 .max_keysize = AES_MAX_KEY_SIZE,
821 .setkey = tegra_aes_setkey,
822 .encrypt = tegra_aes_ecb_encrypt,
823 .decrypt = tegra_aes_ecb_decrypt,
824 },
825 }, {
826 .cra_name = "cbc(aes)",
827 .cra_driver_name = "cbc-aes-tegra",
828 .cra_priority = 300,
829 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
830 .cra_blocksize = AES_BLOCK_SIZE,
831 .cra_alignmask = 3,
832 .cra_type = &crypto_ablkcipher_type,
833 .cra_u.ablkcipher = {
834 .min_keysize = AES_MIN_KEY_SIZE,
835 .max_keysize = AES_MAX_KEY_SIZE,
836 .ivsize = AES_MIN_KEY_SIZE,
837 .setkey = tegra_aes_setkey,
838 .encrypt = tegra_aes_cbc_encrypt,
839 .decrypt = tegra_aes_cbc_decrypt,
840 }
841 }, {
842 .cra_name = "ofb(aes)",
843 .cra_driver_name = "ofb-aes-tegra",
844 .cra_priority = 300,
845 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC,
846 .cra_blocksize = AES_BLOCK_SIZE,
847 .cra_alignmask = 3,
848 .cra_type = &crypto_ablkcipher_type,
849 .cra_u.ablkcipher = {
850 .min_keysize = AES_MIN_KEY_SIZE,
851 .max_keysize = AES_MAX_KEY_SIZE,
852 .ivsize = AES_MIN_KEY_SIZE,
853 .setkey = tegra_aes_setkey,
854 .encrypt = tegra_aes_ofb_encrypt,
855 .decrypt = tegra_aes_ofb_decrypt,
856 }
857 }, {
858 .cra_name = "ansi_cprng",
859 .cra_driver_name = "rng-aes-tegra",
860 .cra_flags = CRYPTO_ALG_TYPE_RNG,
861 .cra_ctxsize = sizeof(struct tegra_aes_ctx),
862 .cra_type = &crypto_rng_type,
863 .cra_u.rng = {
864 .rng_make_random = tegra_aes_get_random,
865 .rng_reset = tegra_aes_rng_reset,
866 .seedsize = AES_KEYSIZE_128 + (2 * DEFAULT_RNG_BLK_SZ),
867 }
868 }
869};
870
871static int tegra_aes_probe(struct platform_device *pdev)
872{
873 struct device *dev = &pdev->dev;
874 struct tegra_aes_dev *dd;
875 struct resource *res;
876 int err = -ENOMEM, i = 0, j;
877
878 dd = devm_kzalloc(dev, sizeof(struct tegra_aes_dev), GFP_KERNEL);
879 if (dd == NULL) {
880 dev_err(dev, "unable to alloc data struct.\n");
881 return err;
882 }
883
884 dd->dev = dev;
885 platform_set_drvdata(pdev, dd);
886
887 dd->slots = devm_kzalloc(dev, sizeof(struct tegra_aes_slot) *
888 AES_NR_KEYSLOTS, GFP_KERNEL);
889 if (dd->slots == NULL) {
890 dev_err(dev, "unable to alloc slot struct.\n");
891 goto out;
892 }
893
894 spin_lock_init(&dd->lock);
895 crypto_init_queue(&dd->queue, TEGRA_AES_QUEUE_LENGTH);
896
897 /* Get the module base address */
898 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
899 if (!res) {
900 dev_err(dev, "invalid resource type: base\n");
901 err = -ENODEV;
902 goto out;
903 }
904
905 if (!devm_request_mem_region(&pdev->dev, res->start,
906 resource_size(res),
907 dev_name(&pdev->dev))) {
908 dev_err(&pdev->dev, "Couldn't request MEM resource\n");
909 return -ENODEV;
910 }
911
912 dd->io_base = devm_ioremap(dev, res->start, resource_size(res));
913 if (!dd->io_base) {
914 dev_err(dev, "can't ioremap register space\n");
915 err = -ENOMEM;
916 goto out;
917 }
918
919 /* Initialize the vde clock */
Sachin Kamat02e28cd2013-09-16 09:01:11 +0530920 dd->aes_clk = devm_clk_get(dev, "vde");
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100921 if (IS_ERR(dd->aes_clk)) {
922 dev_err(dev, "iclock intialization failed.\n");
923 err = -ENODEV;
924 goto out;
925 }
926
927 err = clk_set_rate(dd->aes_clk, ULONG_MAX);
928 if (err) {
929 dev_err(dd->dev, "iclk set_rate fail(%d)\n", err);
930 goto out;
931 }
932
933 /*
934 * the foll contiguous memory is allocated as follows -
935 * - hardware key table
936 * - key schedule
937 */
938 dd->ivkey_base = dma_alloc_coherent(dev, AES_HW_KEY_TABLE_LENGTH_BYTES,
939 &dd->ivkey_phys_base,
940 GFP_KERNEL);
941 if (!dd->ivkey_base) {
942 dev_err(dev, "can not allocate iv/key buffer\n");
943 err = -ENOMEM;
944 goto out;
945 }
946
947 dd->buf_in = dma_alloc_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
948 &dd->dma_buf_in, GFP_KERNEL);
949 if (!dd->buf_in) {
950 dev_err(dev, "can not allocate dma-in buffer\n");
951 err = -ENOMEM;
952 goto out;
953 }
954
955 dd->buf_out = dma_alloc_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
956 &dd->dma_buf_out, GFP_KERNEL);
957 if (!dd->buf_out) {
958 dev_err(dev, "can not allocate dma-out buffer\n");
959 err = -ENOMEM;
960 goto out;
961 }
962
963 init_completion(&dd->op_complete);
964 aes_wq = alloc_workqueue("tegra_aes_wq", WQ_HIGHPRI | WQ_UNBOUND, 1);
965 if (!aes_wq) {
966 dev_err(dev, "alloc_workqueue failed\n");
Peter Senna Tschudin35c41db2012-09-17 19:28:28 +0200967 err = -ENOMEM;
Varun Wadekarf1df57d2012-01-13 16:38:37 +1100968 goto out;
969 }
970
971 /* get the irq */
972 res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
973 if (!res) {
974 dev_err(dev, "invalid resource type: base\n");
975 err = -ENODEV;
976 goto out;
977 }
978 dd->irq = res->start;
979
980 err = devm_request_irq(dev, dd->irq, aes_irq, IRQF_TRIGGER_HIGH |
981 IRQF_SHARED, "tegra-aes", dd);
982 if (err) {
983 dev_err(dev, "request_irq failed\n");
984 goto out;
985 }
986
987 mutex_init(&aes_lock);
988 INIT_LIST_HEAD(&dev_list);
989
990 spin_lock_init(&list_lock);
991 spin_lock(&list_lock);
992 for (i = 0; i < AES_NR_KEYSLOTS; i++) {
993 if (i == SSK_SLOT_NUM)
994 continue;
995 dd->slots[i].slot_num = i;
996 INIT_LIST_HEAD(&dd->slots[i].node);
997 list_add_tail(&dd->slots[i].node, &dev_list);
998 }
999 spin_unlock(&list_lock);
1000
1001 aes_dev = dd;
1002 for (i = 0; i < ARRAY_SIZE(algs); i++) {
Varun Wadekarf1df57d2012-01-13 16:38:37 +11001003 algs[i].cra_priority = 300;
1004 algs[i].cra_ctxsize = sizeof(struct tegra_aes_ctx);
1005 algs[i].cra_module = THIS_MODULE;
1006 algs[i].cra_init = tegra_aes_cra_init;
1007 algs[i].cra_exit = tegra_aes_cra_exit;
1008
1009 err = crypto_register_alg(&algs[i]);
1010 if (err)
1011 goto out;
1012 }
1013
1014 dev_info(dev, "registered");
1015 return 0;
1016
1017out:
1018 for (j = 0; j < i; j++)
1019 crypto_unregister_alg(&algs[j]);
1020 if (dd->ivkey_base)
1021 dma_free_coherent(dev, AES_HW_KEY_TABLE_LENGTH_BYTES,
1022 dd->ivkey_base, dd->ivkey_phys_base);
1023 if (dd->buf_in)
1024 dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
1025 dd->buf_in, dd->dma_buf_in);
1026 if (dd->buf_out)
1027 dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
1028 dd->buf_out, dd->dma_buf_out);
Varun Wadekarf1df57d2012-01-13 16:38:37 +11001029 if (aes_wq)
1030 destroy_workqueue(aes_wq);
1031 spin_lock(&list_lock);
1032 list_del(&dev_list);
1033 spin_unlock(&list_lock);
1034
1035 aes_dev = NULL;
1036
1037 dev_err(dev, "%s: initialization failed.\n", __func__);
1038 return err;
1039}
1040
Greg Kroah-Hartman49cfe4d2012-12-21 13:14:09 -08001041static int tegra_aes_remove(struct platform_device *pdev)
Varun Wadekarf1df57d2012-01-13 16:38:37 +11001042{
1043 struct device *dev = &pdev->dev;
1044 struct tegra_aes_dev *dd = platform_get_drvdata(pdev);
1045 int i;
1046
1047 for (i = 0; i < ARRAY_SIZE(algs); i++)
1048 crypto_unregister_alg(&algs[i]);
1049
1050 cancel_work_sync(&aes_work);
1051 destroy_workqueue(aes_wq);
1052 spin_lock(&list_lock);
1053 list_del(&dev_list);
1054 spin_unlock(&list_lock);
1055
1056 dma_free_coherent(dev, AES_HW_KEY_TABLE_LENGTH_BYTES,
1057 dd->ivkey_base, dd->ivkey_phys_base);
1058 dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
1059 dd->buf_in, dd->dma_buf_in);
1060 dma_free_coherent(dev, AES_HW_DMA_BUFFER_SIZE_BYTES,
1061 dd->buf_out, dd->dma_buf_out);
Varun Wadekarf1df57d2012-01-13 16:38:37 +11001062 aes_dev = NULL;
1063
1064 return 0;
1065}
1066
Greg Kroah-Hartman49cfe4d2012-12-21 13:14:09 -08001067static struct of_device_id tegra_aes_of_match[] = {
Varun Wadekarf1df57d2012-01-13 16:38:37 +11001068 { .compatible = "nvidia,tegra20-aes", },
1069 { .compatible = "nvidia,tegra30-aes", },
1070 { },
1071};
1072
1073static struct platform_driver tegra_aes_driver = {
1074 .probe = tegra_aes_probe,
Greg Kroah-Hartman49cfe4d2012-12-21 13:14:09 -08001075 .remove = tegra_aes_remove,
Varun Wadekarf1df57d2012-01-13 16:38:37 +11001076 .driver = {
1077 .name = "tegra-aes",
1078 .owner = THIS_MODULE,
1079 .of_match_table = tegra_aes_of_match,
1080 },
1081};
1082
1083module_platform_driver(tegra_aes_driver);
1084
1085MODULE_DESCRIPTION("Tegra AES/OFB/CPRNG hw acceleration support.");
1086MODULE_AUTHOR("NVIDIA Corporation");
1087MODULE_LICENSE("GPL v2");