drivers/crypto/dcp.c

   1 /*
   2  * Cryptographic API.
   3  *
   4  * Support for DCP cryptographic accelerator.
   5  *
   6  * Copyright (c) 2013
   7  * Author: Tobias Rauter <tobias.rauter@gmail.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 tegra-aes.c, dcp.c (from freescale SDK) and sahara.c
  14  */
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/errno.h>
  18 #include <linux/kernel.h>
  19 #include <linux/platform_device.h>
  20 #include <linux/dma-mapping.h>
  21 #include <linux/io.h>
  22 #include <linux/mutex.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/completion.h>
  25 #include <linux/workqueue.h>
  26 #include <linux/delay.h>
  27 #include <linux/crypto.h>
  28 #include <linux/miscdevice.h>
  29
  30 #include <crypto/scatterwalk.h>
  31 #include <crypto/aes.h>
  32
  33
  34 /* IOCTL for DCP OTP Key AES - taken from Freescale's SDK*/
  35 #define DBS_IOCTL_BASE   'd'
  36 #define DBS_ENC _IOW(DBS_IOCTL_BASE, 0x00, uint8_t[16])
  37 #define DBS_DEC _IOW(DBS_IOCTL_BASE, 0x01, uint8_t[16])
  38
  39 /* DCP channel used for AES */
  40 #define USED_CHANNEL 1
  41 /* Ring Buffers' maximum size */
  42 #define DCP_MAX_PKG 20
  43
  44 /* Control Register */
  45 #define DCP_REG_CTRL 0x000
  46 #define DCP_CTRL_SFRST (1<<31)
  47 #define DCP_CTRL_CLKGATE (1<<30)
  48 #define DCP_CTRL_CRYPTO_PRESENT (1<<29)
  49 #define DCP_CTRL_SHA_PRESENT (1<<28)
  50 #define DCP_CTRL_GATHER_RES_WRITE (1<<23)
  51 #define DCP_CTRL_ENABLE_CONTEXT_CACHE (1<<22)
  52 #define DCP_CTRL_ENABLE_CONTEXT_SWITCH (1<<21)
  53 #define DCP_CTRL_CH_IRQ_E_0 0x01
  54 #define DCP_CTRL_CH_IRQ_E_1 0x02
  55 #define DCP_CTRL_CH_IRQ_E_2 0x04
  56 #define DCP_CTRL_CH_IRQ_E_3 0x08
  57
  58 /* Status register */
  59 #define DCP_REG_STAT 0x010
  60 #define DCP_STAT_OTP_KEY_READY (1<<28)
  61 #define DCP_STAT_CUR_CHANNEL(stat) ((stat>>24)&0x0F)
  62 #define DCP_STAT_READY_CHANNEL(stat) ((stat>>16)&0x0F)
  63 #define DCP_STAT_IRQ(stat) (stat&0x0F)
  64 #define DCP_STAT_CHAN_0 (0x01)
  65 #define DCP_STAT_CHAN_1 (0x02)
  66 #define DCP_STAT_CHAN_2 (0x04)
  67 #define DCP_STAT_CHAN_3 (0x08)
  68
  69 /* Channel Control Register */
  70 #define DCP_REG_CHAN_CTRL 0x020
  71 #define DCP_CHAN_CTRL_CH0_IRQ_MERGED (1<<16)
  72 #define DCP_CHAN_CTRL_HIGH_PRIO_0 (0x0100)
  73 #define DCP_CHAN_CTRL_HIGH_PRIO_1 (0x0200)
  74 #define DCP_CHAN_CTRL_HIGH_PRIO_2 (0x0400)
  75 #define DCP_CHAN_CTRL_HIGH_PRIO_3 (0x0800)
  76 #define DCP_CHAN_CTRL_ENABLE_0 (0x01)
  77 #define DCP_CHAN_CTRL_ENABLE_1 (0x02)
  78 #define DCP_CHAN_CTRL_ENABLE_2 (0x04)
  79 #define DCP_CHAN_CTRL_ENABLE_3 (0x08)
  80
  81 /*
  82  * Channel Registers:
  83  * The DCP has 4 channels. Each of this channels
  84  * has 4 registers (command pointer, semaphore, status and options).
  85  * The address of register REG of channel CHAN is obtained by
  86  * dcp_chan_reg(REG, CHAN)
  87  */
  88 #define DCP_REG_CHAN_PTR        0x00000100
  89 #define DCP_REG_CHAN_SEMA       0x00000110
  90 #define DCP_REG_CHAN_STAT       0x00000120
  91 #define DCP_REG_CHAN_OPT        0x00000130
  92
  93 #define DCP_CHAN_STAT_NEXT_CHAIN_IS_0   0x010000
  94 #define DCP_CHAN_STAT_NO_CHAIN          0x020000
  95 #define DCP_CHAN_STAT_CONTEXT_ERROR     0x030000
  96 #define DCP_CHAN_STAT_PAYLOAD_ERROR     0x040000
  97 #define DCP_CHAN_STAT_INVALID_MODE      0x050000
  98 #define DCP_CHAN_STAT_PAGEFAULT         0x40
  99 #define DCP_CHAN_STAT_DST               0x20
 100 #define DCP_CHAN_STAT_SRC               0x10
 101 #define DCP_CHAN_STAT_PACKET            0x08
 102 #define DCP_CHAN_STAT_SETUP             0x04
 103 #define DCP_CHAN_STAT_MISMATCH          0x02
 104
 105 /* hw packet control*/
 106
 107 #define DCP_PKT_PAYLOAD_KEY     (1<<11)
 108 #define DCP_PKT_OTP_KEY         (1<<10)
 109 #define DCP_PKT_CIPHER_INIT     (1<<9)
 110 #define DCP_PKG_CIPHER_ENCRYPT  (1<<8)
 111 #define DCP_PKT_CIPHER_ENABLE   (1<<5)
 112 #define DCP_PKT_DECR_SEM        (1<<1)
 113 #define DCP_PKT_CHAIN           (1<<2)
 114 #define DCP_PKT_IRQ             1
 115
 116 #define DCP_PKT_MODE_CBC        (1<<4)
 117 #define DCP_PKT_KEYSELECT_OTP   (0xFF<<8)
 118
 119 /* cipher flags */
 120 #define DCP_ENC         0x0001
 121 #define DCP_DEC         0x0002
 122 #define DCP_ECB         0x0004
 123 #define DCP_CBC         0x0008
 124 #define DCP_CBC_INIT    0x0010
 125 #define DCP_NEW_KEY     0x0040
 126 #define DCP_OTP_KEY     0x0080
 127 #define DCP_AES         0x1000
 128
 129 /* DCP Flags */
 130 #define DCP_FLAG_BUSY   0x01
 131 #define DCP_FLAG_PRODUCING      0x02
 132
 133 /* clock defines */
 134 #define CLOCK_ON        1
 135 #define CLOCK_OFF       0
 136
 137 struct dcp_dev_req_ctx {
 138         int mode;
 139 };
 140
 141 struct dcp_op {
 142         unsigned int            flags;
 143         u8                      key[AES_KEYSIZE_128];
 144         int                     keylen;
 145
 146         struct ablkcipher_request       *req;
 147         struct crypto_ablkcipher        *fallback;
 148
 149         uint32_t stat;
 150         uint32_t pkt1;
 151         uint32_t pkt2;
 152         struct ablkcipher_walk walk;
 153 };
 154
 155 struct dcp_dev {
 156         struct device *dev;
 157         void __iomem *dcp_regs_base;
 158
 159         int dcp_vmi_irq;
 160         int dcp_irq;
 161
 162         spinlock_t queue_lock;
 163         struct crypto_queue queue;
 164
 165         uint32_t pkt_produced;
 166         uint32_t pkt_consumed;
 167
 168         struct dcp_hw_packet *hw_pkg[DCP_MAX_PKG];
 169         dma_addr_t hw_phys_pkg;
 170
 171         /* [KEY][IV] Both with 16 Bytes */
 172         u8 *payload_base;
 173         dma_addr_t payload_base_dma;
 174
 175
 176         struct tasklet_struct   done_task;
 177         struct tasklet_struct   queue_task;
 178         struct timer_list       watchdog;
 179
 180         unsigned long           flags;
 181
 182         struct dcp_op *ctx;
 183
 184         struct miscdevice dcp_bootstream_misc;
 185 };
 186
 187 struct dcp_hw_packet {
 188         uint32_t next;
 189         uint32_t pkt1;
 190         uint32_t pkt2;
 191         uint32_t src;
 192         uint32_t dst;
 193         uint32_t size;
 194         uint32_t payload;
 195         uint32_t stat;
 196 };
 197
 198 static struct dcp_dev *global_dev;
 199
 200 static inline u32 dcp_chan_reg(u32 reg, int chan)
 201 {
 202         return reg + (chan) * 0x40;
 203 }
 204
 205 static inline void dcp_write(struct dcp_dev *dev, u32 data, u32 reg)
 206 {
 207         writel(data, dev->dcp_regs_base + reg);
 208 }
 209
 210 static inline void dcp_set(struct dcp_dev *dev, u32 data, u32 reg)
 211 {
 212         writel(data, dev->dcp_regs_base + (reg | 0x04));
 213 }
 214
 215 static inline void dcp_clear(struct dcp_dev *dev, u32 data, u32 reg)
 216 {
 217         writel(data, dev->dcp_regs_base + (reg | 0x08));
 218 }
 219
 220 static inline void dcp_toggle(struct dcp_dev *dev, u32 data, u32 reg)
 221 {
 222         writel(data, dev->dcp_regs_base + (reg | 0x0C));
 223 }
 224
 225 static inline unsigned int dcp_read(struct dcp_dev *dev, u32 reg)
 226 {
 227         return readl(dev->dcp_regs_base + reg);
 228 }
 229
 230 static void dcp_dma_unmap(struct dcp_dev *dev, struct dcp_hw_packet *pkt)
 231 {
 232         dma_unmap_page(dev->dev, pkt->src, pkt->size, DMA_TO_DEVICE);
 233         dma_unmap_page(dev->dev, pkt->dst, pkt->size, DMA_FROM_DEVICE);
 234         dev_dbg(dev->dev, "unmap packet %x", (unsigned int) pkt);
 235 }
 236
 237 static int dcp_dma_map(struct dcp_dev *dev,
 238         struct ablkcipher_walk *walk, struct dcp_hw_packet *pkt)
 239 {
 240         dev_dbg(dev->dev, "map packet %x", (unsigned int) pkt);
 241         /* align to length = 16 */
 242         pkt->size = walk->nbytes - (walk->nbytes % 16);
 243
 244         pkt->src = dma_map_page(dev->dev, walk->src.page, walk->src.offset,
 245                 pkt->size, DMA_TO_DEVICE);
 246
 247         if (pkt->src == 0) {
 248                 dev_err(dev->dev, "Unable to map src");
 249                 return -ENOMEM;
 250         }
 251
 252         pkt->dst = dma_map_page(dev->dev, walk->dst.page, walk->dst.offset,
 253                 pkt->size, DMA_FROM_DEVICE);
 254
 255         if (pkt->dst == 0) {
 256                 dev_err(dev->dev, "Unable to map dst");
 257                 dma_unmap_page(dev->dev, pkt->src, pkt->size, DMA_TO_DEVICE);
 258                 return -ENOMEM;
 259         }
 260
 261         return 0;
 262 }
 263
 264 static void dcp_op_one(struct dcp_dev *dev, struct dcp_hw_packet *pkt,
 265                         uint8_t last)
 266 {
 267         struct dcp_op *ctx = dev->ctx;
 268         pkt->pkt1 = ctx->pkt1;
 269         pkt->pkt2 = ctx->pkt2;
 270
 271         pkt->payload = (u32) dev->payload_base_dma;
 272         pkt->stat = 0;
 273
 274         if (ctx->flags & DCP_CBC_INIT) {
 275                 pkt->pkt1 |= DCP_PKT_CIPHER_INIT;
 276                 ctx->flags &= ~DCP_CBC_INIT;
 277         }
 278
 279         mod_timer(&dev->watchdog, jiffies + msecs_to_jiffies(500));
 280         pkt->pkt1 |= DCP_PKT_IRQ;
 281         if (!last)
 282                 pkt->pkt1 |= DCP_PKT_CHAIN;
 283
 284         dev->pkt_produced++;
 285
 286         dcp_write(dev, 1,
 287                 dcp_chan_reg(DCP_REG_CHAN_SEMA, USED_CHANNEL));
 288 }
 289
 290 static void dcp_op_proceed(struct dcp_dev *dev)
 291 {
 292         struct dcp_op *ctx = dev->ctx;
 293         struct dcp_hw_packet *pkt;
 294
 295         while (ctx->walk.nbytes) {
 296                 int err = 0;
 297
 298                 pkt = dev->hw_pkg[dev->pkt_produced % DCP_MAX_PKG];
 299                 err = dcp_dma_map(dev, &ctx->walk, pkt);
 300                 if (err) {
 301                         dev->ctx->stat |= err;
 302                         /* start timer to wait for already set up calls */
 303                         mod_timer(&dev->watchdog,
 304                                 jiffies + msecs_to_jiffies(500));
 305                         break;
 306                 }
 307
 308
 309                 err = ctx->walk.nbytes - pkt->size;
 310                 ablkcipher_walk_done(dev->ctx->req, &dev->ctx->walk, err);
 311
 312                 dcp_op_one(dev, pkt, ctx->walk.nbytes == 0);
 313                 /* we have to wait if no space is left in buffer */
 314                 if (dev->pkt_produced - dev->pkt_consumed == DCP_MAX_PKG)
 315                         break;
 316         }
 317         clear_bit(DCP_FLAG_PRODUCING, &dev->flags);
 318 }
 319
 320 static void dcp_op_start(struct dcp_dev *dev, uint8_t use_walk)
 321 {
 322         struct dcp_op *ctx = dev->ctx;
 323
 324         if (ctx->flags & DCP_NEW_KEY) {
 325                 memcpy(dev->payload_base, ctx->key, ctx->keylen);
 326                 ctx->flags &= ~DCP_NEW_KEY;
 327         }
 328
 329         ctx->pkt1 = 0;
 330         ctx->pkt1 |= DCP_PKT_CIPHER_ENABLE;
 331         ctx->pkt1 |= DCP_PKT_DECR_SEM;
 332
 333         if (ctx->flags & DCP_OTP_KEY)
 334                 ctx->pkt1 |= DCP_PKT_OTP_KEY;
 335         else
 336                 ctx->pkt1 |= DCP_PKT_PAYLOAD_KEY;
 337
 338         if (ctx->flags & DCP_ENC)
 339                 ctx->pkt1 |= DCP_PKG_CIPHER_ENCRYPT;
 340
 341         ctx->pkt2 = 0;
 342         if (ctx->flags & DCP_CBC)
 343                 ctx->pkt2 |= DCP_PKT_MODE_CBC;
 344
 345         dev->pkt_produced = 0;
 346         dev->pkt_consumed = 0;
 347
 348         ctx->stat = 0;
 349         dcp_clear(dev, -1, dcp_chan_reg(DCP_REG_CHAN_STAT, USED_CHANNEL));
 350         dcp_write(dev, (u32) dev->hw_phys_pkg,
 351                 dcp_chan_reg(DCP_REG_CHAN_PTR, USED_CHANNEL));
 352
 353         set_bit(DCP_FLAG_PRODUCING, &dev->flags);
 354
 355         if (use_walk) {
 356                 ablkcipher_walk_init(&ctx->walk, ctx->req->dst,
 357                                 ctx->req->src, ctx->req->nbytes);
 358                 ablkcipher_walk_phys(ctx->req, &ctx->walk);
 359                 dcp_op_proceed(dev);
 360         } else {
 361                 dcp_op_one(dev, dev->hw_pkg[0], 1);
 362                 clear_bit(DCP_FLAG_PRODUCING, &dev->flags);
 363         }
 364 }
 365
 366 static void dcp_done_task(unsigned long data)
 367 {
 368         struct dcp_dev *dev = (struct dcp_dev *)data;
 369         struct dcp_hw_packet *last_packet;
 370         int fin;
 371         fin = 0;
 372
 373         for (last_packet = dev->hw_pkg[(dev->pkt_consumed) % DCP_MAX_PKG];
 374                 last_packet->stat == 1;
 375                 last_packet =
 376                         dev->hw_pkg[++(dev->pkt_consumed) % DCP_MAX_PKG]) {
 377
 378                 dcp_dma_unmap(dev, last_packet);
 379                 last_packet->stat = 0;
 380                 fin++;
 381         }
 382         /* the last call of this function already consumed this IRQ's packet */
 383         if (fin == 0)
 384                 return;
 385
 386         dev_dbg(dev->dev,
 387                 "Packet(s) done with status %x; finished: %d, produced:%d, complete consumed: %d",
 388                 dev->ctx->stat, fin, dev->pkt_produced, dev->pkt_consumed);
 389
 390         last_packet = dev->hw_pkg[(dev->pkt_consumed - 1) % DCP_MAX_PKG];
 391         if (!dev->ctx->stat && last_packet->pkt1 & DCP_PKT_CHAIN) {
 392                 if (!test_and_set_bit(DCP_FLAG_PRODUCING, &dev->flags))
 393                         dcp_op_proceed(dev);
 394                 return;
 395         }
 396
 397         while (unlikely(dev->pkt_consumed < dev->pkt_produced)) {
 398                 dcp_dma_unmap(dev,
 399                         dev->hw_pkg[dev->pkt_consumed++ % DCP_MAX_PKG]);
 400         }
 401
 402         if (dev->ctx->flags & DCP_OTP_KEY) {
 403                 /* we used the miscdevice, no walk to finish */
 404                 clear_bit(DCP_FLAG_BUSY, &dev->flags);
 405                 return;
 406         }
 407
 408         ablkcipher_walk_complete(&dev->ctx->walk);
 409         dev->ctx->req->base.complete(&dev->ctx->req->base,
 410                         dev->ctx->stat);
 411         dev->ctx->req = NULL;
 412         /* in case there are other requests in the queue */
 413         tasklet_schedule(&dev->queue_task);
 414 }
 415
 416 static void dcp_watchdog(unsigned long data)
 417 {
 418         struct dcp_dev *dev = (struct dcp_dev *)data;
 419         dev->ctx->stat |= dcp_read(dev,
 420                         dcp_chan_reg(DCP_REG_CHAN_STAT, USED_CHANNEL));
 421
 422         dev_err(dev->dev, "Timeout, Channel status: %x", dev->ctx->stat);
 423
 424         if (!dev->ctx->stat)
 425                 dev->ctx->stat = -ETIMEDOUT;
 426
 427         dcp_done_task(data);
 428 }
 429
 430
 431 static irqreturn_t dcp_common_irq(int irq, void *context)
 432 {
 433         u32 msk;
 434         struct dcp_dev *dev = (struct dcp_dev *) context;
 435
 436         del_timer(&dev->watchdog);
 437
 438         msk = DCP_STAT_IRQ(dcp_read(dev, DCP_REG_STAT));
 439         dcp_clear(dev, msk, DCP_REG_STAT);
 440         if (msk == 0)
 441                 return IRQ_NONE;
 442
 443         dev->ctx->stat |= dcp_read(dev,
 444                         dcp_chan_reg(DCP_REG_CHAN_STAT, USED_CHANNEL));
 445
 446         if (msk & DCP_STAT_CHAN_1)
 447                 tasklet_schedule(&dev->done_task);
 448
 449         return IRQ_HANDLED;
 450 }
 451
 452 static irqreturn_t dcp_vmi_irq(int irq, void *context)
 453 {
 454         return dcp_common_irq(irq, context);
 455 }
 456
 457 static irqreturn_t dcp_irq(int irq, void *context)
 458 {
 459         return dcp_common_irq(irq, context);
 460 }
 461
 462 static void dcp_crypt(struct dcp_dev *dev, struct dcp_op *ctx)
 463 {
 464         dev->ctx = ctx;
 465
 466         if ((ctx->flags & DCP_CBC) && ctx->req->info) {
 467                 ctx->flags |= DCP_CBC_INIT;
 468                 memcpy(dev->payload_base + AES_KEYSIZE_128,
 469                         ctx->req->info, AES_KEYSIZE_128);
 470         }
 471
 472         dcp_op_start(dev, 1);
 473 }
 474
 475 static void dcp_queue_task(unsigned long data)
 476 {
 477         struct dcp_dev *dev = (struct dcp_dev *) data;
 478         struct crypto_async_request *async_req, *backlog;
 479         struct crypto_ablkcipher *tfm;
 480         struct dcp_op *ctx;
 481         struct dcp_dev_req_ctx *rctx;
 482         struct ablkcipher_request *req;
 483         unsigned long flags;
 484
 485         spin_lock_irqsave(&dev->queue_lock, flags);
 486
 487         backlog = crypto_get_backlog(&dev->queue);
 488         async_req = crypto_dequeue_request(&dev->queue);
 489
 490         spin_unlock_irqrestore(&dev->queue_lock, flags);
 491
 492         if (!async_req)
 493                 goto ret_nothing_done;
 494
 495         if (backlog)
 496                 backlog->complete(backlog, -EINPROGRESS);
 497
 498         req = ablkcipher_request_cast(async_req);
 499         tfm = crypto_ablkcipher_reqtfm(req);
 500         rctx = ablkcipher_request_ctx(req);
 501         ctx = crypto_ablkcipher_ctx(tfm);
 502
 503         if (!req->src || !req->dst)
 504                 goto ret_nothing_done;
 505
 506         ctx->flags |= rctx->mode;
 507         ctx->req = req;
 508
 509         dcp_crypt(dev, ctx);
 510
 511         return;
 512
 513 ret_nothing_done:
 514         clear_bit(DCP_FLAG_BUSY, &dev->flags);
 515 }
 516
 517
 518 static int dcp_cra_init(struct crypto_tfm *tfm)
 519 {
 520         const char *name = tfm->__crt_alg->cra_name;
 521         struct dcp_op *ctx = crypto_tfm_ctx(tfm);
 522
 523         tfm->crt_ablkcipher.reqsize = sizeof(struct dcp_dev_req_ctx);
 524
 525         ctx->fallback = crypto_alloc_ablkcipher(name, 0,
 526                                 CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK);
 527
 528         if (IS_ERR(ctx->fallback)) {
 529                 dev_err(global_dev->dev, "Error allocating fallback algo %s\n",
 530                         name);
 531                 return PTR_ERR(ctx->fallback);
 532         }
 533
 534         return 0;
 535 }
 536
 537 static void dcp_cra_exit(struct crypto_tfm *tfm)
 538 {
 539         struct dcp_op *ctx = crypto_tfm_ctx(tfm);
 540
 541         if (ctx->fallback)
 542                 crypto_free_ablkcipher(ctx->fallback);
 543
 544         ctx->fallback = NULL;
 545 }
 546
 547 /* async interface */
 548 static int dcp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
 549                 unsigned int len)
 550 {
 551         struct dcp_op *ctx = crypto_ablkcipher_ctx(tfm);
 552         unsigned int ret = 0;
 553         ctx->keylen = len;
 554         ctx->flags = 0;
 555         if (len == AES_KEYSIZE_128) {
 556                 if (memcmp(ctx->key, key, AES_KEYSIZE_128)) {
 557                         memcpy(ctx->key, key, len);
 558                         ctx->flags |= DCP_NEW_KEY;
 559                 }
 560                 return 0;
 561         }
 562
 563         ctx->fallback->base.crt_flags &= ~CRYPTO_TFM_REQ_MASK;
 564         ctx->fallback->base.crt_flags |=
 565                 (tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
 566
 567         ret = crypto_ablkcipher_setkey(ctx->fallback, key, len);
 568         if (ret) {
 569                 struct crypto_tfm *tfm_aux = crypto_ablkcipher_tfm(tfm);
 570
 571                 tfm_aux->crt_flags &= ~CRYPTO_TFM_RES_MASK;
 572                 tfm_aux->crt_flags |=
 573                         (ctx->fallback->base.crt_flags & CRYPTO_TFM_RES_MASK);
 574         }
 575         return ret;
 576 }
 577
 578 static int dcp_aes_cbc_crypt(struct ablkcipher_request *req, int mode)
 579 {
 580         struct dcp_dev_req_ctx *rctx = ablkcipher_request_ctx(req);
 581         struct dcp_dev *dev = global_dev;
 582         unsigned long flags;
 583         int err = 0;
 584
 585         if (!IS_ALIGNED(req->nbytes, AES_BLOCK_SIZE))
 586                 return -EINVAL;
 587
 588         rctx->mode = mode;
 589
 590         spin_lock_irqsave(&dev->queue_lock, flags);
 591         err = ablkcipher_enqueue_request(&dev->queue, req);
 592         spin_unlock_irqrestore(&dev->queue_lock, flags);
 593
 594         flags = test_and_set_bit(DCP_FLAG_BUSY, &dev->flags);
 595
 596         if (!(flags & DCP_FLAG_BUSY))
 597                 tasklet_schedule(&dev->queue_task);
 598
 599         return err;
 600 }
 601
 602 static int dcp_aes_cbc_encrypt(struct ablkcipher_request *req)
 603 {
 604         struct crypto_tfm *tfm =
 605                 crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
 606         struct dcp_op *ctx = crypto_ablkcipher_ctx(
 607                 crypto_ablkcipher_reqtfm(req));
 608
 609         if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
 610                 int err = 0;
 611                 ablkcipher_request_set_tfm(req, ctx->fallback);
 612                 err = crypto_ablkcipher_encrypt(req);
 613                 ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
 614                 return err;
 615         }
 616
 617         return dcp_aes_cbc_crypt(req, DCP_AES | DCP_ENC | DCP_CBC);
 618 }
 619
 620 static int dcp_aes_cbc_decrypt(struct ablkcipher_request *req)
 621 {
 622         struct crypto_tfm *tfm =
 623                 crypto_ablkcipher_tfm(crypto_ablkcipher_reqtfm(req));
 624         struct dcp_op *ctx = crypto_ablkcipher_ctx(
 625                 crypto_ablkcipher_reqtfm(req));
 626
 627         if (unlikely(ctx->keylen != AES_KEYSIZE_128)) {
 628                 int err = 0;
 629                 ablkcipher_request_set_tfm(req, ctx->fallback);
 630                 err = crypto_ablkcipher_decrypt(req);
 631                 ablkcipher_request_set_tfm(req, __crypto_ablkcipher_cast(tfm));
 632                 return err;
 633         }
 634         return dcp_aes_cbc_crypt(req, DCP_AES | DCP_DEC | DCP_CBC);
 635 }
 636
 637 static struct crypto_alg algs[] = {
 638         {
 639                 .cra_name = "cbc(aes)",
 640                 .cra_driver_name = "dcp-cbc-aes",
 641                 .cra_alignmask = 3,
 642                 .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC |
 643                           CRYPTO_ALG_NEED_FALLBACK,
 644                 .cra_blocksize = AES_KEYSIZE_128,
 645                 .cra_type = &crypto_ablkcipher_type,
 646                 .cra_priority = 300,
 647                 .cra_u.ablkcipher = {
 648                         .min_keysize =  AES_KEYSIZE_128,
 649                         .max_keysize = AES_KEYSIZE_128,
 650                         .setkey = dcp_aes_setkey,
 651                         .encrypt = dcp_aes_cbc_encrypt,
 652                         .decrypt = dcp_aes_cbc_decrypt,
 653                         .ivsize = AES_KEYSIZE_128,
 654                 }
 655
 656         },
 657 };
 658
 659 /* DCP bootstream verification interface: uses OTP key for crypto */
 660 static int dcp_bootstream_open(struct inode *inode, struct file *file)
 661 {
 662         file->private_data = container_of((file->private_data),
 663                         struct dcp_dev, dcp_bootstream_misc);
 664         return 0;
 665 }
 666
 667 static long dcp_bootstream_ioctl(struct file *file,
 668                                          unsigned int cmd, unsigned long arg)
 669 {
 670         struct dcp_dev *dev = (struct dcp_dev *) file->private_data;
 671         void __user *argp = (void __user *)arg;
 672         int ret;
 673
 674         if (dev == NULL)
 675                 return -EBADF;
 676
 677         if (cmd != DBS_ENC && cmd != DBS_DEC)
 678                 return -EINVAL;
 679
 680         if (copy_from_user(dev->payload_base, argp, 16))
 681                 return -EFAULT;
 682
 683         if (test_and_set_bit(DCP_FLAG_BUSY, &dev->flags))
 684                 return -EAGAIN;
 685
 686         dev->ctx = kzalloc(sizeof(struct dcp_op), GFP_KERNEL);
 687         if (!dev->ctx) {
 688                 dev_err(dev->dev,
 689                         "cannot allocate context for OTP crypto");
 690                 clear_bit(DCP_FLAG_BUSY, &dev->flags);
 691                 return -ENOMEM;
 692         }
 693
 694         dev->ctx->flags = DCP_AES | DCP_ECB | DCP_OTP_KEY | DCP_CBC_INIT;
 695         dev->ctx->flags |= (cmd == DBS_ENC) ? DCP_ENC : DCP_DEC;
 696         dev->hw_pkg[0]->src = dev->payload_base_dma;
 697         dev->hw_pkg[0]->dst = dev->payload_base_dma;
 698         dev->hw_pkg[0]->size = 16;
 699
 700         dcp_op_start(dev, 0);
 701
 702         while (test_bit(DCP_FLAG_BUSY, &dev->flags))
 703                 cpu_relax();
 704
 705         ret = dev->ctx->stat;
 706         if (!ret && copy_to_user(argp, dev->payload_base, 16))
 707                 ret =  -EFAULT;
 708
 709         kfree(dev->ctx);
 710
 711         return ret;
 712 }
 713
 714 static const struct file_operations dcp_bootstream_fops = {
 715         .owner =                THIS_MODULE,
 716         .unlocked_ioctl =       dcp_bootstream_ioctl,
 717         .open =                 dcp_bootstream_open,
 718 };
 719
 720 static int dcp_probe(struct platform_device *pdev)
 721 {
 722         struct dcp_dev *dev = NULL;
 723         struct resource *r;
 724         int i, ret, j;
 725
 726         dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
 727         if (!dev)
 728                 return -ENOMEM;
 729
 730         global_dev = dev;
 731         dev->dev = &pdev->dev;
 732
 733         platform_set_drvdata(pdev, dev);
 734
 735         r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 736         dev->dcp_regs_base = devm_ioremap_resource(&pdev->dev, r);
 737         if (IS_ERR(dev->dcp_regs_base))
 738                 return PTR_ERR(dev->dcp_regs_base);
 739
 740         dcp_set(dev, DCP_CTRL_SFRST, DCP_REG_CTRL);
 741         udelay(10);
 742         dcp_clear(dev, DCP_CTRL_SFRST | DCP_CTRL_CLKGATE, DCP_REG_CTRL);
 743
 744         dcp_write(dev, DCP_CTRL_GATHER_RES_WRITE |
 745                 DCP_CTRL_ENABLE_CONTEXT_CACHE | DCP_CTRL_CH_IRQ_E_1,
 746                 DCP_REG_CTRL);
 747
 748         dcp_write(dev, DCP_CHAN_CTRL_ENABLE_1, DCP_REG_CHAN_CTRL);
 749
 750         for (i = 0; i < 4; i++)
 751                 dcp_clear(dev, -1, dcp_chan_reg(DCP_REG_CHAN_STAT, i));
 752
 753         dcp_clear(dev, -1, DCP_REG_STAT);
 754
 755
 756         r = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 757         if (!r) {
 758                 dev_err(&pdev->dev, "can't get IRQ resource (0)\n");
 759                 return -EIO;
 760         }
 761         dev->dcp_vmi_irq = r->start;
 762         ret = devm_request_irq(&pdev->dev, dev->dcp_vmi_irq, dcp_vmi_irq, 0,
 763                                "dcp", dev);
 764         if (ret != 0) {
 765                 dev_err(&pdev->dev, "can't request_irq (0)\n");
 766                 return -EIO;
 767         }
 768
 769         r = platform_get_resource(pdev, IORESOURCE_IRQ, 1);
 770         if (!r) {
 771                 dev_err(&pdev->dev, "can't get IRQ resource (1)\n");
 772                 return -EIO;
 773         }
 774         dev->dcp_irq = r->start;
 775         ret = devm_request_irq(&pdev->dev, dev->dcp_irq, dcp_irq, 0, "dcp",
 776                                dev);
 777         if (ret != 0) {
 778                 dev_err(&pdev->dev, "can't request_irq (1)\n");
 779                 return -EIO;
 780         }
 781
 782         dev->hw_pkg[0] = dma_alloc_coherent(&pdev->dev,
 783                         DCP_MAX_PKG * sizeof(struct dcp_hw_packet),
 784                         &dev->hw_phys_pkg,
 785                         GFP_KERNEL);
 786         if (!dev->hw_pkg[0]) {
 787                 dev_err(&pdev->dev, "Could not allocate hw descriptors\n");
 788                 return -ENOMEM;
 789         }
 790
 791         for (i = 1; i < DCP_MAX_PKG; i++) {
 792                 dev->hw_pkg[i - 1]->next = dev->hw_phys_pkg
 793                                 + i * sizeof(struct dcp_hw_packet);
 794                 dev->hw_pkg[i] = dev->hw_pkg[i - 1] + 1;
 795         }
 796         dev->hw_pkg[i - 1]->next = dev->hw_phys_pkg;
 797
 798
 799         dev->payload_base = dma_alloc_coherent(&pdev->dev, 2 * AES_KEYSIZE_128,
 800                         &dev->payload_base_dma, GFP_KERNEL);
 801         if (!dev->payload_base) {
 802                 dev_err(&pdev->dev, "Could not allocate memory for key\n");
 803                 ret = -ENOMEM;
 804                 goto err_free_hw_packet;
 805         }
 806         tasklet_init(&dev->queue_task, dcp_queue_task,
 807                 (unsigned long) dev);
 808         tasklet_init(&dev->done_task, dcp_done_task,
 809                 (unsigned long) dev);
 810         spin_lock_init(&dev->queue_lock);
 811
 812         crypto_init_queue(&dev->queue, 10);
 813
 814         init_timer(&dev->watchdog);
 815         dev->watchdog.function = &dcp_watchdog;
 816         dev->watchdog.data = (unsigned long)dev;
 817
 818         dev->dcp_bootstream_misc.minor = MISC_DYNAMIC_MINOR,
 819         dev->dcp_bootstream_misc.name = "dcpboot",
 820         dev->dcp_bootstream_misc.fops = &dcp_bootstream_fops,
 821         ret = misc_register(&dev->dcp_bootstream_misc);
 822         if (ret != 0) {
 823                 dev_err(dev->dev, "Unable to register misc device\n");
 824                 goto err_free_key_iv;
 825         }
 826
 827         for (i = 0; i < ARRAY_SIZE(algs); i++) {
 828                 algs[i].cra_priority = 300;
 829                 algs[i].cra_ctxsize = sizeof(struct dcp_op);
 830                 algs[i].cra_module = THIS_MODULE;
 831                 algs[i].cra_init = dcp_cra_init;
 832                 algs[i].cra_exit = dcp_cra_exit;
 833                 if (crypto_register_alg(&algs[i])) {
 834                         dev_err(&pdev->dev, "register algorithm failed\n");
 835                         ret = -ENOMEM;
 836                         goto err_unregister;
 837                 }
 838         }
 839         dev_notice(&pdev->dev, "DCP crypto enabled.!\n");
 840
 841         return 0;
 842
 843 err_unregister:
 844         for (j = 0; j < i; j++)
 845                 crypto_unregister_alg(&algs[j]);
 846 err_free_key_iv:
 847         tasklet_kill(&dev->done_task);
 848         tasklet_kill(&dev->queue_task);
 849         dma_free_coherent(&pdev->dev, 2 * AES_KEYSIZE_128, dev->payload_base,
 850                         dev->payload_base_dma);
 851 err_free_hw_packet:
 852         dma_free_coherent(&pdev->dev, DCP_MAX_PKG *
 853                 sizeof(struct dcp_hw_packet), dev->hw_pkg[0],
 854                 dev->hw_phys_pkg);
 855
 856         return ret;
 857 }
 858
 859 static int dcp_remove(struct platform_device *pdev)
 860 {
 861         struct dcp_dev *dev;
 862         int j;
 863         dev = platform_get_drvdata(pdev);
 864
 865         misc_deregister(&dev->dcp_bootstream_misc);
 866
 867         for (j = 0; j < ARRAY_SIZE(algs); j++)
 868                 crypto_unregister_alg(&algs[j]);
 869
 870         tasklet_kill(&dev->done_task);
 871         tasklet_kill(&dev->queue_task);
 872
 873         dma_free_coherent(&pdev->dev, 2 * AES_KEYSIZE_128, dev->payload_base,
 874                         dev->payload_base_dma);
 875
 876         dma_free_coherent(&pdev->dev,
 877                         DCP_MAX_PKG * sizeof(struct dcp_hw_packet),
 878                         dev->hw_pkg[0], dev->hw_phys_pkg);
 879
 880         return 0;
 881 }
 882
 883 static struct of_device_id fs_dcp_of_match[] = {
 884         {       .compatible = "fsl-dcp"},
 885         {},
 886 };
 887
 888 static struct platform_driver fs_dcp_driver = {
 889         .probe = dcp_probe,
 890         .remove = dcp_remove,
 891         .driver = {
 892                 .name = "fsl-dcp",
 893                 .owner = THIS_MODULE,
 894                 .of_match_table = fs_dcp_of_match
 895         }
 896 };
 897
 898 module_platform_driver(fs_dcp_driver);
 899
 900
 901 MODULE_AUTHOR("Tobias Rauter <tobias.rauter@gmail.com>");
 902 MODULE_DESCRIPTION("Freescale DCP Crypto Driver");
 903 MODULE_LICENSE("GPL");