linux/drivers/crypto/mxs-dcp.c
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   1/*
   2 * Freescale i.MX23/i.MX28 Data Co-Processor driver
   3 *
   4 * Copyright (C) 2013 Marek Vasut <marex@denx.de>
   5 *
   6 * The code contained herein is licensed under the GNU General Public
   7 * License. You may obtain a copy of the GNU General Public License
   8 * Version 2 or later at the following locations:
   9 *
  10 * http://www.opensource.org/licenses/gpl-license.html
  11 * http://www.gnu.org/copyleft/gpl.html
  12 */
  13
  14#include <linux/dma-mapping.h>
  15#include <linux/interrupt.h>
  16#include <linux/io.h>
  17#include <linux/kernel.h>
  18#include <linux/kthread.h>
  19#include <linux/module.h>
  20#include <linux/of.h>
  21#include <linux/platform_device.h>
  22#include <linux/stmp_device.h>
  23
  24#include <crypto/aes.h>
  25#include <crypto/sha.h>
  26#include <crypto/internal/hash.h>
  27#include <crypto/internal/skcipher.h>
  28
  29#define DCP_MAX_CHANS   4
  30#define DCP_BUF_SZ      PAGE_SIZE
  31
  32#define DCP_ALIGNMENT   64
  33
  34/* DCP DMA descriptor. */
  35struct dcp_dma_desc {
  36        uint32_t        next_cmd_addr;
  37        uint32_t        control0;
  38        uint32_t        control1;
  39        uint32_t        source;
  40        uint32_t        destination;
  41        uint32_t        size;
  42        uint32_t        payload;
  43        uint32_t        status;
  44};
  45
  46/* Coherent aligned block for bounce buffering. */
  47struct dcp_coherent_block {
  48        uint8_t                 aes_in_buf[DCP_BUF_SZ];
  49        uint8_t                 aes_out_buf[DCP_BUF_SZ];
  50        uint8_t                 sha_in_buf[DCP_BUF_SZ];
  51
  52        uint8_t                 aes_key[2 * AES_KEYSIZE_128];
  53
  54        struct dcp_dma_desc     desc[DCP_MAX_CHANS];
  55};
  56
  57struct dcp {
  58        struct device                   *dev;
  59        void __iomem                    *base;
  60
  61        uint32_t                        caps;
  62
  63        struct dcp_coherent_block       *coh;
  64
  65        struct completion               completion[DCP_MAX_CHANS];
  66        struct mutex                    mutex[DCP_MAX_CHANS];
  67        struct task_struct              *thread[DCP_MAX_CHANS];
  68        struct crypto_queue             queue[DCP_MAX_CHANS];
  69};
  70
  71enum dcp_chan {
  72        DCP_CHAN_HASH_SHA       = 0,
  73        DCP_CHAN_CRYPTO         = 2,
  74};
  75
  76struct dcp_async_ctx {
  77        /* Common context */
  78        enum dcp_chan   chan;
  79        uint32_t        fill;
  80
  81        /* SHA Hash-specific context */
  82        struct mutex                    mutex;
  83        uint32_t                        alg;
  84        unsigned int                    hot:1;
  85
  86        /* Crypto-specific context */
  87        struct crypto_skcipher          *fallback;
  88        unsigned int                    key_len;
  89        uint8_t                         key[AES_KEYSIZE_128];
  90};
  91
  92struct dcp_aes_req_ctx {
  93        unsigned int    enc:1;
  94        unsigned int    ecb:1;
  95};
  96
  97struct dcp_sha_req_ctx {
  98        unsigned int    init:1;
  99        unsigned int    fini:1;
 100};
 101
 102/*
 103 * There can even be only one instance of the MXS DCP due to the
 104 * design of Linux Crypto API.
 105 */
 106static struct dcp *global_sdcp;
 107
 108/* DCP register layout. */
 109#define MXS_DCP_CTRL                            0x00
 110#define MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES     (1 << 23)
 111#define MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING     (1 << 22)
 112
 113#define MXS_DCP_STAT                            0x10
 114#define MXS_DCP_STAT_CLR                        0x18
 115#define MXS_DCP_STAT_IRQ_MASK                   0xf
 116
 117#define MXS_DCP_CHANNELCTRL                     0x20
 118#define MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK 0xff
 119
 120#define MXS_DCP_CAPABILITY1                     0x40
 121#define MXS_DCP_CAPABILITY1_SHA256              (4 << 16)
 122#define MXS_DCP_CAPABILITY1_SHA1                (1 << 16)
 123#define MXS_DCP_CAPABILITY1_AES128              (1 << 0)
 124
 125#define MXS_DCP_CONTEXT                         0x50
 126
 127#define MXS_DCP_CH_N_CMDPTR(n)                  (0x100 + ((n) * 0x40))
 128
 129#define MXS_DCP_CH_N_SEMA(n)                    (0x110 + ((n) * 0x40))
 130
 131#define MXS_DCP_CH_N_STAT(n)                    (0x120 + ((n) * 0x40))
 132#define MXS_DCP_CH_N_STAT_CLR(n)                (0x128 + ((n) * 0x40))
 133
 134/* DMA descriptor bits. */
 135#define MXS_DCP_CONTROL0_HASH_TERM              (1 << 13)
 136#define MXS_DCP_CONTROL0_HASH_INIT              (1 << 12)
 137#define MXS_DCP_CONTROL0_PAYLOAD_KEY            (1 << 11)
 138#define MXS_DCP_CONTROL0_CIPHER_ENCRYPT         (1 << 8)
 139#define MXS_DCP_CONTROL0_CIPHER_INIT            (1 << 9)
 140#define MXS_DCP_CONTROL0_ENABLE_HASH            (1 << 6)
 141#define MXS_DCP_CONTROL0_ENABLE_CIPHER          (1 << 5)
 142#define MXS_DCP_CONTROL0_DECR_SEMAPHORE         (1 << 1)
 143#define MXS_DCP_CONTROL0_INTERRUPT              (1 << 0)
 144
 145#define MXS_DCP_CONTROL1_HASH_SELECT_SHA256     (2 << 16)
 146#define MXS_DCP_CONTROL1_HASH_SELECT_SHA1       (0 << 16)
 147#define MXS_DCP_CONTROL1_CIPHER_MODE_CBC        (1 << 4)
 148#define MXS_DCP_CONTROL1_CIPHER_MODE_ECB        (0 << 4)
 149#define MXS_DCP_CONTROL1_CIPHER_SELECT_AES128   (0 << 0)
 150
 151static int mxs_dcp_start_dma(struct dcp_async_ctx *actx)
 152{
 153        struct dcp *sdcp = global_sdcp;
 154        const int chan = actx->chan;
 155        uint32_t stat;
 156        unsigned long ret;
 157        struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
 158
 159        dma_addr_t desc_phys = dma_map_single(sdcp->dev, desc, sizeof(*desc),
 160                                              DMA_TO_DEVICE);
 161
 162        reinit_completion(&sdcp->completion[chan]);
 163
 164        /* Clear status register. */
 165        writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(chan));
 166
 167        /* Load the DMA descriptor. */
 168        writel(desc_phys, sdcp->base + MXS_DCP_CH_N_CMDPTR(chan));
 169
 170        /* Increment the semaphore to start the DMA transfer. */
 171        writel(1, sdcp->base + MXS_DCP_CH_N_SEMA(chan));
 172
 173        ret = wait_for_completion_timeout(&sdcp->completion[chan],
 174                                          msecs_to_jiffies(1000));
 175        if (!ret) {
 176                dev_err(sdcp->dev, "Channel %i timeout (DCP_STAT=0x%08x)\n",
 177                        chan, readl(sdcp->base + MXS_DCP_STAT));
 178                return -ETIMEDOUT;
 179        }
 180
 181        stat = readl(sdcp->base + MXS_DCP_CH_N_STAT(chan));
 182        if (stat & 0xff) {
 183                dev_err(sdcp->dev, "Channel %i error (CH_STAT=0x%08x)\n",
 184                        chan, stat);
 185                return -EINVAL;
 186        }
 187
 188        dma_unmap_single(sdcp->dev, desc_phys, sizeof(*desc), DMA_TO_DEVICE);
 189
 190        return 0;
 191}
 192
 193/*
 194 * Encryption (AES128)
 195 */
 196static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
 197                           struct ablkcipher_request *req, int init)
 198{
 199        struct dcp *sdcp = global_sdcp;
 200        struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
 201        struct dcp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
 202        int ret;
 203
 204        dma_addr_t key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key,
 205                                             2 * AES_KEYSIZE_128,
 206                                             DMA_TO_DEVICE);
 207        dma_addr_t src_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_in_buf,
 208                                             DCP_BUF_SZ, DMA_TO_DEVICE);
 209        dma_addr_t dst_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_out_buf,
 210                                             DCP_BUF_SZ, DMA_FROM_DEVICE);
 211
 212        /* Fill in the DMA descriptor. */
 213        desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
 214                    MXS_DCP_CONTROL0_INTERRUPT |
 215                    MXS_DCP_CONTROL0_ENABLE_CIPHER;
 216
 217        /* Payload contains the key. */
 218        desc->control0 |= MXS_DCP_CONTROL0_PAYLOAD_KEY;
 219
 220        if (rctx->enc)
 221                desc->control0 |= MXS_DCP_CONTROL0_CIPHER_ENCRYPT;
 222        if (init)
 223                desc->control0 |= MXS_DCP_CONTROL0_CIPHER_INIT;
 224
 225        desc->control1 = MXS_DCP_CONTROL1_CIPHER_SELECT_AES128;
 226
 227        if (rctx->ecb)
 228                desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_ECB;
 229        else
 230                desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_CBC;
 231
 232        desc->next_cmd_addr = 0;
 233        desc->source = src_phys;
 234        desc->destination = dst_phys;
 235        desc->size = actx->fill;
 236        desc->payload = key_phys;
 237        desc->status = 0;
 238
 239        ret = mxs_dcp_start_dma(actx);
 240
 241        dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
 242                         DMA_TO_DEVICE);
 243        dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
 244        dma_unmap_single(sdcp->dev, dst_phys, DCP_BUF_SZ, DMA_FROM_DEVICE);
 245
 246        return ret;
 247}
 248
 249static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
 250{
 251        struct dcp *sdcp = global_sdcp;
 252
 253        struct ablkcipher_request *req = ablkcipher_request_cast(arq);
 254        struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
 255        struct dcp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
 256
 257        struct scatterlist *dst = req->dst;
 258        struct scatterlist *src = req->src;
 259        const int nents = sg_nents(req->src);
 260
 261        const int out_off = DCP_BUF_SZ;
 262        uint8_t *in_buf = sdcp->coh->aes_in_buf;
 263        uint8_t *out_buf = sdcp->coh->aes_out_buf;
 264
 265        uint8_t *out_tmp, *src_buf, *dst_buf = NULL;
 266        uint32_t dst_off = 0;
 267
 268        uint8_t *key = sdcp->coh->aes_key;
 269
 270        int ret = 0;
 271        int split = 0;
 272        unsigned int i, len, clen, rem = 0;
 273        int init = 0;
 274
 275        actx->fill = 0;
 276
 277        /* Copy the key from the temporary location. */
 278        memcpy(key, actx->key, actx->key_len);
 279
 280        if (!rctx->ecb) {
 281                /* Copy the CBC IV just past the key. */
 282                memcpy(key + AES_KEYSIZE_128, req->info, AES_KEYSIZE_128);
 283                /* CBC needs the INIT set. */
 284                init = 1;
 285        } else {
 286                memset(key + AES_KEYSIZE_128, 0, AES_KEYSIZE_128);
 287        }
 288
 289        for_each_sg(req->src, src, nents, i) {
 290                src_buf = sg_virt(src);
 291                len = sg_dma_len(src);
 292
 293                do {
 294                        if (actx->fill + len > out_off)
 295                                clen = out_off - actx->fill;
 296                        else
 297                                clen = len;
 298
 299                        memcpy(in_buf + actx->fill, src_buf, clen);
 300                        len -= clen;
 301                        src_buf += clen;
 302                        actx->fill += clen;
 303
 304                        /*
 305                         * If we filled the buffer or this is the last SG,
 306                         * submit the buffer.
 307                         */
 308                        if (actx->fill == out_off || sg_is_last(src)) {
 309                                ret = mxs_dcp_run_aes(actx, req, init);
 310                                if (ret)
 311                                        return ret;
 312                                init = 0;
 313
 314                                out_tmp = out_buf;
 315                                while (dst && actx->fill) {
 316                                        if (!split) {
 317                                                dst_buf = sg_virt(dst);
 318                                                dst_off = 0;
 319                                        }
 320                                        rem = min(sg_dma_len(dst) - dst_off,
 321                                                  actx->fill);
 322
 323                                        memcpy(dst_buf + dst_off, out_tmp, rem);
 324                                        out_tmp += rem;
 325                                        dst_off += rem;
 326                                        actx->fill -= rem;
 327
 328                                        if (dst_off == sg_dma_len(dst)) {
 329                                                dst = sg_next(dst);
 330                                                split = 0;
 331                                        } else {
 332                                                split = 1;
 333                                        }
 334                                }
 335                        }
 336                } while (len);
 337        }
 338
 339        return ret;
 340}
 341
 342static int dcp_chan_thread_aes(void *data)
 343{
 344        struct dcp *sdcp = global_sdcp;
 345        const int chan = DCP_CHAN_CRYPTO;
 346
 347        struct crypto_async_request *backlog;
 348        struct crypto_async_request *arq;
 349
 350        int ret;
 351
 352        do {
 353                __set_current_state(TASK_INTERRUPTIBLE);
 354
 355                mutex_lock(&sdcp->mutex[chan]);
 356                backlog = crypto_get_backlog(&sdcp->queue[chan]);
 357                arq = crypto_dequeue_request(&sdcp->queue[chan]);
 358                mutex_unlock(&sdcp->mutex[chan]);
 359
 360                if (backlog)
 361                        backlog->complete(backlog, -EINPROGRESS);
 362
 363                if (arq) {
 364                        ret = mxs_dcp_aes_block_crypt(arq);
 365                        arq->complete(arq, ret);
 366                        continue;
 367                }
 368
 369                schedule();
 370        } while (!kthread_should_stop());
 371
 372        return 0;
 373}
 374
 375static int mxs_dcp_block_fallback(struct ablkcipher_request *req, int enc)
 376{
 377        struct crypto_ablkcipher *tfm = crypto_ablkcipher_reqtfm(req);
 378        struct dcp_async_ctx *ctx = crypto_ablkcipher_ctx(tfm);
 379        SKCIPHER_REQUEST_ON_STACK(subreq, ctx->fallback);
 380        int ret;
 381
 382        skcipher_request_set_tfm(subreq, ctx->fallback);
 383        skcipher_request_set_callback(subreq, req->base.flags, NULL, NULL);
 384        skcipher_request_set_crypt(subreq, req->src, req->dst,
 385                                   req->nbytes, req->info);
 386
 387        if (enc)
 388                ret = crypto_skcipher_encrypt(subreq);
 389        else
 390                ret = crypto_skcipher_decrypt(subreq);
 391
 392        skcipher_request_zero(subreq);
 393
 394        return ret;
 395}
 396
 397static int mxs_dcp_aes_enqueue(struct ablkcipher_request *req, int enc, int ecb)
 398{
 399        struct dcp *sdcp = global_sdcp;
 400        struct crypto_async_request *arq = &req->base;
 401        struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
 402        struct dcp_aes_req_ctx *rctx = ablkcipher_request_ctx(req);
 403        int ret;
 404
 405        if (unlikely(actx->key_len != AES_KEYSIZE_128))
 406                return mxs_dcp_block_fallback(req, enc);
 407
 408        rctx->enc = enc;
 409        rctx->ecb = ecb;
 410        actx->chan = DCP_CHAN_CRYPTO;
 411
 412        mutex_lock(&sdcp->mutex[actx->chan]);
 413        ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
 414        mutex_unlock(&sdcp->mutex[actx->chan]);
 415
 416        wake_up_process(sdcp->thread[actx->chan]);
 417
 418        return -EINPROGRESS;
 419}
 420
 421static int mxs_dcp_aes_ecb_decrypt(struct ablkcipher_request *req)
 422{
 423        return mxs_dcp_aes_enqueue(req, 0, 1);
 424}
 425
 426static int mxs_dcp_aes_ecb_encrypt(struct ablkcipher_request *req)
 427{
 428        return mxs_dcp_aes_enqueue(req, 1, 1);
 429}
 430
 431static int mxs_dcp_aes_cbc_decrypt(struct ablkcipher_request *req)
 432{
 433        return mxs_dcp_aes_enqueue(req, 0, 0);
 434}
 435
 436static int mxs_dcp_aes_cbc_encrypt(struct ablkcipher_request *req)
 437{
 438        return mxs_dcp_aes_enqueue(req, 1, 0);
 439}
 440
 441static int mxs_dcp_aes_setkey(struct crypto_ablkcipher *tfm, const u8 *key,
 442                              unsigned int len)
 443{
 444        struct dcp_async_ctx *actx = crypto_ablkcipher_ctx(tfm);
 445        unsigned int ret;
 446
 447        /*
 448         * AES 128 is supposed by the hardware, store key into temporary
 449         * buffer and exit. We must use the temporary buffer here, since
 450         * there can still be an operation in progress.
 451         */
 452        actx->key_len = len;
 453        if (len == AES_KEYSIZE_128) {
 454                memcpy(actx->key, key, len);
 455                return 0;
 456        }
 457
 458        /*
 459         * If the requested AES key size is not supported by the hardware,
 460         * but is supported by in-kernel software implementation, we use
 461         * software fallback.
 462         */
 463        crypto_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK);
 464        crypto_skcipher_set_flags(actx->fallback,
 465                                  tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
 466
 467        ret = crypto_skcipher_setkey(actx->fallback, key, len);
 468        if (!ret)
 469                return 0;
 470
 471        tfm->base.crt_flags &= ~CRYPTO_TFM_RES_MASK;
 472        tfm->base.crt_flags |= crypto_skcipher_get_flags(actx->fallback) &
 473                               CRYPTO_TFM_RES_MASK;
 474
 475        return ret;
 476}
 477
 478static int mxs_dcp_aes_fallback_init(struct crypto_tfm *tfm)
 479{
 480        const char *name = crypto_tfm_alg_name(tfm);
 481        const uint32_t flags = CRYPTO_ALG_ASYNC | CRYPTO_ALG_NEED_FALLBACK;
 482        struct dcp_async_ctx *actx = crypto_tfm_ctx(tfm);
 483        struct crypto_skcipher *blk;
 484
 485        blk = crypto_alloc_skcipher(name, 0, flags);
 486        if (IS_ERR(blk))
 487                return PTR_ERR(blk);
 488
 489        actx->fallback = blk;
 490        tfm->crt_ablkcipher.reqsize = sizeof(struct dcp_aes_req_ctx);
 491        return 0;
 492}
 493
 494static void mxs_dcp_aes_fallback_exit(struct crypto_tfm *tfm)
 495{
 496        struct dcp_async_ctx *actx = crypto_tfm_ctx(tfm);
 497
 498        crypto_free_skcipher(actx->fallback);
 499}
 500
 501/*
 502 * Hashing (SHA1/SHA256)
 503 */
 504static int mxs_dcp_run_sha(struct ahash_request *req)
 505{
 506        struct dcp *sdcp = global_sdcp;
 507        int ret;
 508
 509        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 510        struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
 511        struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
 512        struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
 513
 514        struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
 515
 516        dma_addr_t digest_phys = 0;
 517        dma_addr_t buf_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_in_buf,
 518                                             DCP_BUF_SZ, DMA_TO_DEVICE);
 519
 520        /* Fill in the DMA descriptor. */
 521        desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
 522                    MXS_DCP_CONTROL0_INTERRUPT |
 523                    MXS_DCP_CONTROL0_ENABLE_HASH;
 524        if (rctx->init)
 525                desc->control0 |= MXS_DCP_CONTROL0_HASH_INIT;
 526
 527        desc->control1 = actx->alg;
 528        desc->next_cmd_addr = 0;
 529        desc->source = buf_phys;
 530        desc->destination = 0;
 531        desc->size = actx->fill;
 532        desc->payload = 0;
 533        desc->status = 0;
 534
 535        /* Set HASH_TERM bit for last transfer block. */
 536        if (rctx->fini) {
 537                digest_phys = dma_map_single(sdcp->dev, req->result,
 538                                             halg->digestsize, DMA_FROM_DEVICE);
 539                desc->control0 |= MXS_DCP_CONTROL0_HASH_TERM;
 540                desc->payload = digest_phys;
 541        }
 542
 543        ret = mxs_dcp_start_dma(actx);
 544
 545        if (rctx->fini)
 546                dma_unmap_single(sdcp->dev, digest_phys, halg->digestsize,
 547                                 DMA_FROM_DEVICE);
 548
 549        dma_unmap_single(sdcp->dev, buf_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
 550
 551        return ret;
 552}
 553
 554static int dcp_sha_req_to_buf(struct crypto_async_request *arq)
 555{
 556        struct dcp *sdcp = global_sdcp;
 557
 558        struct ahash_request *req = ahash_request_cast(arq);
 559        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 560        struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
 561        struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
 562        struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
 563        const int nents = sg_nents(req->src);
 564
 565        uint8_t *in_buf = sdcp->coh->sha_in_buf;
 566
 567        uint8_t *src_buf;
 568
 569        struct scatterlist *src;
 570
 571        unsigned int i, len, clen;
 572        int ret;
 573
 574        int fin = rctx->fini;
 575        if (fin)
 576                rctx->fini = 0;
 577
 578        for_each_sg(req->src, src, nents, i) {
 579                src_buf = sg_virt(src);
 580                len = sg_dma_len(src);
 581
 582                do {
 583                        if (actx->fill + len > DCP_BUF_SZ)
 584                                clen = DCP_BUF_SZ - actx->fill;
 585                        else
 586                                clen = len;
 587
 588                        memcpy(in_buf + actx->fill, src_buf, clen);
 589                        len -= clen;
 590                        src_buf += clen;
 591                        actx->fill += clen;
 592
 593                        /*
 594                         * If we filled the buffer and still have some
 595                         * more data, submit the buffer.
 596                         */
 597                        if (len && actx->fill == DCP_BUF_SZ) {
 598                                ret = mxs_dcp_run_sha(req);
 599                                if (ret)
 600                                        return ret;
 601                                actx->fill = 0;
 602                                rctx->init = 0;
 603                        }
 604                } while (len);
 605        }
 606
 607        if (fin) {
 608                rctx->fini = 1;
 609
 610                /* Submit whatever is left. */
 611                if (!req->result)
 612                        return -EINVAL;
 613
 614                ret = mxs_dcp_run_sha(req);
 615                if (ret)
 616                        return ret;
 617
 618                actx->fill = 0;
 619
 620                /* For some reason, the result is flipped. */
 621                for (i = 0; i < halg->digestsize / 2; i++) {
 622                        swap(req->result[i],
 623                             req->result[halg->digestsize - i - 1]);
 624                }
 625        }
 626
 627        return 0;
 628}
 629
 630static int dcp_chan_thread_sha(void *data)
 631{
 632        struct dcp *sdcp = global_sdcp;
 633        const int chan = DCP_CHAN_HASH_SHA;
 634
 635        struct crypto_async_request *backlog;
 636        struct crypto_async_request *arq;
 637
 638        struct dcp_sha_req_ctx *rctx;
 639
 640        struct ahash_request *req;
 641        int ret, fini;
 642
 643        do {
 644                __set_current_state(TASK_INTERRUPTIBLE);
 645
 646                mutex_lock(&sdcp->mutex[chan]);
 647                backlog = crypto_get_backlog(&sdcp->queue[chan]);
 648                arq = crypto_dequeue_request(&sdcp->queue[chan]);
 649                mutex_unlock(&sdcp->mutex[chan]);
 650
 651                if (backlog)
 652                        backlog->complete(backlog, -EINPROGRESS);
 653
 654                if (arq) {
 655                        req = ahash_request_cast(arq);
 656                        rctx = ahash_request_ctx(req);
 657
 658                        ret = dcp_sha_req_to_buf(arq);
 659                        fini = rctx->fini;
 660                        arq->complete(arq, ret);
 661                        if (!fini)
 662                                continue;
 663                }
 664
 665                schedule();
 666        } while (!kthread_should_stop());
 667
 668        return 0;
 669}
 670
 671static int dcp_sha_init(struct ahash_request *req)
 672{
 673        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 674        struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
 675
 676        struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
 677
 678        /*
 679         * Start hashing session. The code below only inits the
 680         * hashing session context, nothing more.
 681         */
 682        memset(actx, 0, sizeof(*actx));
 683
 684        if (strcmp(halg->base.cra_name, "sha1") == 0)
 685                actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA1;
 686        else
 687                actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA256;
 688
 689        actx->fill = 0;
 690        actx->hot = 0;
 691        actx->chan = DCP_CHAN_HASH_SHA;
 692
 693        mutex_init(&actx->mutex);
 694
 695        return 0;
 696}
 697
 698static int dcp_sha_update_fx(struct ahash_request *req, int fini)
 699{
 700        struct dcp *sdcp = global_sdcp;
 701
 702        struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
 703        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 704        struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
 705
 706        int ret;
 707
 708        /*
 709         * Ignore requests that have no data in them and are not
 710         * the trailing requests in the stream of requests.
 711         */
 712        if (!req->nbytes && !fini)
 713                return 0;
 714
 715        mutex_lock(&actx->mutex);
 716
 717        rctx->fini = fini;
 718
 719        if (!actx->hot) {
 720                actx->hot = 1;
 721                rctx->init = 1;
 722        }
 723
 724        mutex_lock(&sdcp->mutex[actx->chan]);
 725        ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
 726        mutex_unlock(&sdcp->mutex[actx->chan]);
 727
 728        wake_up_process(sdcp->thread[actx->chan]);
 729        mutex_unlock(&actx->mutex);
 730
 731        return -EINPROGRESS;
 732}
 733
 734static int dcp_sha_update(struct ahash_request *req)
 735{
 736        return dcp_sha_update_fx(req, 0);
 737}
 738
 739static int dcp_sha_final(struct ahash_request *req)
 740{
 741        ahash_request_set_crypt(req, NULL, req->result, 0);
 742        req->nbytes = 0;
 743        return dcp_sha_update_fx(req, 1);
 744}
 745
 746static int dcp_sha_finup(struct ahash_request *req)
 747{
 748        return dcp_sha_update_fx(req, 1);
 749}
 750
 751static int dcp_sha_digest(struct ahash_request *req)
 752{
 753        int ret;
 754
 755        ret = dcp_sha_init(req);
 756        if (ret)
 757                return ret;
 758
 759        return dcp_sha_finup(req);
 760}
 761
 762static int dcp_sha_cra_init(struct crypto_tfm *tfm)
 763{
 764        crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
 765                                 sizeof(struct dcp_sha_req_ctx));
 766        return 0;
 767}
 768
 769static void dcp_sha_cra_exit(struct crypto_tfm *tfm)
 770{
 771}
 772
 773/* AES 128 ECB and AES 128 CBC */
 774static struct crypto_alg dcp_aes_algs[] = {
 775        {
 776                .cra_name               = "ecb(aes)",
 777                .cra_driver_name        = "ecb-aes-dcp",
 778                .cra_priority           = 400,
 779                .cra_alignmask          = 15,
 780                .cra_flags              = CRYPTO_ALG_TYPE_ABLKCIPHER |
 781                                          CRYPTO_ALG_ASYNC |
 782                                          CRYPTO_ALG_NEED_FALLBACK,
 783                .cra_init               = mxs_dcp_aes_fallback_init,
 784                .cra_exit               = mxs_dcp_aes_fallback_exit,
 785                .cra_blocksize          = AES_BLOCK_SIZE,
 786                .cra_ctxsize            = sizeof(struct dcp_async_ctx),
 787                .cra_type               = &crypto_ablkcipher_type,
 788                .cra_module             = THIS_MODULE,
 789                .cra_u  = {
 790                        .ablkcipher = {
 791                                .min_keysize    = AES_MIN_KEY_SIZE,
 792                                .max_keysize    = AES_MAX_KEY_SIZE,
 793                                .setkey         = mxs_dcp_aes_setkey,
 794                                .encrypt        = mxs_dcp_aes_ecb_encrypt,
 795                                .decrypt        = mxs_dcp_aes_ecb_decrypt
 796                        },
 797                },
 798        }, {
 799                .cra_name               = "cbc(aes)",
 800                .cra_driver_name        = "cbc-aes-dcp",
 801                .cra_priority           = 400,
 802                .cra_alignmask          = 15,
 803                .cra_flags              = CRYPTO_ALG_TYPE_ABLKCIPHER |
 804                                          CRYPTO_ALG_ASYNC |
 805                                          CRYPTO_ALG_NEED_FALLBACK,
 806                .cra_init               = mxs_dcp_aes_fallback_init,
 807                .cra_exit               = mxs_dcp_aes_fallback_exit,
 808                .cra_blocksize          = AES_BLOCK_SIZE,
 809                .cra_ctxsize            = sizeof(struct dcp_async_ctx),
 810                .cra_type               = &crypto_ablkcipher_type,
 811                .cra_module             = THIS_MODULE,
 812                .cra_u = {
 813                        .ablkcipher = {
 814                                .min_keysize    = AES_MIN_KEY_SIZE,
 815                                .max_keysize    = AES_MAX_KEY_SIZE,
 816                                .setkey         = mxs_dcp_aes_setkey,
 817                                .encrypt        = mxs_dcp_aes_cbc_encrypt,
 818                                .decrypt        = mxs_dcp_aes_cbc_decrypt,
 819                                .ivsize         = AES_BLOCK_SIZE,
 820                        },
 821                },
 822        },
 823};
 824
 825/* SHA1 */
 826static struct ahash_alg dcp_sha1_alg = {
 827        .init   = dcp_sha_init,
 828        .update = dcp_sha_update,
 829        .final  = dcp_sha_final,
 830        .finup  = dcp_sha_finup,
 831        .digest = dcp_sha_digest,
 832        .halg   = {
 833                .digestsize     = SHA1_DIGEST_SIZE,
 834                .base           = {
 835                        .cra_name               = "sha1",
 836                        .cra_driver_name        = "sha1-dcp",
 837                        .cra_priority           = 400,
 838                        .cra_alignmask          = 63,
 839                        .cra_flags              = CRYPTO_ALG_ASYNC,
 840                        .cra_blocksize          = SHA1_BLOCK_SIZE,
 841                        .cra_ctxsize            = sizeof(struct dcp_async_ctx),
 842                        .cra_module             = THIS_MODULE,
 843                        .cra_init               = dcp_sha_cra_init,
 844                        .cra_exit               = dcp_sha_cra_exit,
 845                },
 846        },
 847};
 848
 849/* SHA256 */
 850static struct ahash_alg dcp_sha256_alg = {
 851        .init   = dcp_sha_init,
 852        .update = dcp_sha_update,
 853        .final  = dcp_sha_final,
 854        .finup  = dcp_sha_finup,
 855        .digest = dcp_sha_digest,
 856        .halg   = {
 857                .digestsize     = SHA256_DIGEST_SIZE,
 858                .base           = {
 859                        .cra_name               = "sha256",
 860                        .cra_driver_name        = "sha256-dcp",
 861                        .cra_priority           = 400,
 862                        .cra_alignmask          = 63,
 863                        .cra_flags              = CRYPTO_ALG_ASYNC,
 864                        .cra_blocksize          = SHA256_BLOCK_SIZE,
 865                        .cra_ctxsize            = sizeof(struct dcp_async_ctx),
 866                        .cra_module             = THIS_MODULE,
 867                        .cra_init               = dcp_sha_cra_init,
 868                        .cra_exit               = dcp_sha_cra_exit,
 869                },
 870        },
 871};
 872
 873static irqreturn_t mxs_dcp_irq(int irq, void *context)
 874{
 875        struct dcp *sdcp = context;
 876        uint32_t stat;
 877        int i;
 878
 879        stat = readl(sdcp->base + MXS_DCP_STAT);
 880        stat &= MXS_DCP_STAT_IRQ_MASK;
 881        if (!stat)
 882                return IRQ_NONE;
 883
 884        /* Clear the interrupts. */
 885        writel(stat, sdcp->base + MXS_DCP_STAT_CLR);
 886
 887        /* Complete the DMA requests that finished. */
 888        for (i = 0; i < DCP_MAX_CHANS; i++)
 889                if (stat & (1 << i))
 890                        complete(&sdcp->completion[i]);
 891
 892        return IRQ_HANDLED;
 893}
 894
 895static int mxs_dcp_probe(struct platform_device *pdev)
 896{
 897        struct device *dev = &pdev->dev;
 898        struct dcp *sdcp = NULL;
 899        int i, ret;
 900
 901        struct resource *iores;
 902        int dcp_vmi_irq, dcp_irq;
 903
 904        if (global_sdcp) {
 905                dev_err(dev, "Only one DCP instance allowed!\n");
 906                return -ENODEV;
 907        }
 908
 909        iores = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 910        dcp_vmi_irq = platform_get_irq(pdev, 0);
 911        if (dcp_vmi_irq < 0)
 912                return dcp_vmi_irq;
 913
 914        dcp_irq = platform_get_irq(pdev, 1);
 915        if (dcp_irq < 0)
 916                return dcp_irq;
 917
 918        sdcp = devm_kzalloc(dev, sizeof(*sdcp), GFP_KERNEL);
 919        if (!sdcp)
 920                return -ENOMEM;
 921
 922        sdcp->dev = dev;
 923        sdcp->base = devm_ioremap_resource(dev, iores);
 924        if (IS_ERR(sdcp->base))
 925                return PTR_ERR(sdcp->base);
 926
 927
 928        ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
 929                               "dcp-vmi-irq", sdcp);
 930        if (ret) {
 931                dev_err(dev, "Failed to claim DCP VMI IRQ!\n");
 932                return ret;
 933        }
 934
 935        ret = devm_request_irq(dev, dcp_irq, mxs_dcp_irq, 0,
 936                               "dcp-irq", sdcp);
 937        if (ret) {
 938                dev_err(dev, "Failed to claim DCP IRQ!\n");
 939                return ret;
 940        }
 941
 942        /* Allocate coherent helper block. */
 943        sdcp->coh = devm_kzalloc(dev, sizeof(*sdcp->coh) + DCP_ALIGNMENT,
 944                                   GFP_KERNEL);
 945        if (!sdcp->coh)
 946                return -ENOMEM;
 947
 948        /* Re-align the structure so it fits the DCP constraints. */
 949        sdcp->coh = PTR_ALIGN(sdcp->coh, DCP_ALIGNMENT);
 950
 951        /* Restart the DCP block. */
 952        ret = stmp_reset_block(sdcp->base);
 953        if (ret)
 954                return ret;
 955
 956        /* Initialize control register. */
 957        writel(MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES |
 958               MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING | 0xf,
 959               sdcp->base + MXS_DCP_CTRL);
 960
 961        /* Enable all DCP DMA channels. */
 962        writel(MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK,
 963               sdcp->base + MXS_DCP_CHANNELCTRL);
 964
 965        /*
 966         * We do not enable context switching. Give the context buffer a
 967         * pointer to an illegal address so if context switching is
 968         * inadvertantly enabled, the DCP will return an error instead of
 969         * trashing good memory. The DCP DMA cannot access ROM, so any ROM
 970         * address will do.
 971         */
 972        writel(0xffff0000, sdcp->base + MXS_DCP_CONTEXT);
 973        for (i = 0; i < DCP_MAX_CHANS; i++)
 974                writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(i));
 975        writel(0xffffffff, sdcp->base + MXS_DCP_STAT_CLR);
 976
 977        global_sdcp = sdcp;
 978
 979        platform_set_drvdata(pdev, sdcp);
 980
 981        for (i = 0; i < DCP_MAX_CHANS; i++) {
 982                mutex_init(&sdcp->mutex[i]);
 983                init_completion(&sdcp->completion[i]);
 984                crypto_init_queue(&sdcp->queue[i], 50);
 985        }
 986
 987        /* Create the SHA and AES handler threads. */
 988        sdcp->thread[DCP_CHAN_HASH_SHA] = kthread_run(dcp_chan_thread_sha,
 989                                                      NULL, "mxs_dcp_chan/sha");
 990        if (IS_ERR(sdcp->thread[DCP_CHAN_HASH_SHA])) {
 991                dev_err(dev, "Error starting SHA thread!\n");
 992                return PTR_ERR(sdcp->thread[DCP_CHAN_HASH_SHA]);
 993        }
 994
 995        sdcp->thread[DCP_CHAN_CRYPTO] = kthread_run(dcp_chan_thread_aes,
 996                                                    NULL, "mxs_dcp_chan/aes");
 997        if (IS_ERR(sdcp->thread[DCP_CHAN_CRYPTO])) {
 998                dev_err(dev, "Error starting SHA thread!\n");
 999                ret = PTR_ERR(sdcp->thread[DCP_CHAN_CRYPTO]);
1000                goto err_destroy_sha_thread;
1001        }
1002
1003        /* Register the various crypto algorithms. */
1004        sdcp->caps = readl(sdcp->base + MXS_DCP_CAPABILITY1);
1005
1006        if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128) {
1007                ret = crypto_register_algs(dcp_aes_algs,
1008                                           ARRAY_SIZE(dcp_aes_algs));
1009                if (ret) {
1010                        /* Failed to register algorithm. */
1011                        dev_err(dev, "Failed to register AES crypto!\n");
1012                        goto err_destroy_aes_thread;
1013                }
1014        }
1015
1016        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1) {
1017                ret = crypto_register_ahash(&dcp_sha1_alg);
1018                if (ret) {
1019                        dev_err(dev, "Failed to register %s hash!\n",
1020                                dcp_sha1_alg.halg.base.cra_name);
1021                        goto err_unregister_aes;
1022                }
1023        }
1024
1025        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256) {
1026                ret = crypto_register_ahash(&dcp_sha256_alg);
1027                if (ret) {
1028                        dev_err(dev, "Failed to register %s hash!\n",
1029                                dcp_sha256_alg.halg.base.cra_name);
1030                        goto err_unregister_sha1;
1031                }
1032        }
1033
1034        return 0;
1035
1036err_unregister_sha1:
1037        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1038                crypto_unregister_ahash(&dcp_sha1_alg);
1039
1040err_unregister_aes:
1041        if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1042                crypto_unregister_algs(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1043
1044err_destroy_aes_thread:
1045        kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1046
1047err_destroy_sha_thread:
1048        kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1049        return ret;
1050}
1051
1052static int mxs_dcp_remove(struct platform_device *pdev)
1053{
1054        struct dcp *sdcp = platform_get_drvdata(pdev);
1055
1056        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256)
1057                crypto_unregister_ahash(&dcp_sha256_alg);
1058
1059        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1060                crypto_unregister_ahash(&dcp_sha1_alg);
1061
1062        if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1063                crypto_unregister_algs(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1064
1065        kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1066        kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1067
1068        platform_set_drvdata(pdev, NULL);
1069
1070        global_sdcp = NULL;
1071
1072        return 0;
1073}
1074
1075static const struct of_device_id mxs_dcp_dt_ids[] = {
1076        { .compatible = "fsl,imx23-dcp", .data = NULL, },
1077        { .compatible = "fsl,imx28-dcp", .data = NULL, },
1078        { /* sentinel */ }
1079};
1080
1081MODULE_DEVICE_TABLE(of, mxs_dcp_dt_ids);
1082
1083static struct platform_driver mxs_dcp_driver = {
1084        .probe  = mxs_dcp_probe,
1085        .remove = mxs_dcp_remove,
1086        .driver = {
1087                .name           = "mxs-dcp",
1088                .of_match_table = mxs_dcp_dt_ids,
1089        },
1090};
1091
1092module_platform_driver(mxs_dcp_driver);
1093
1094MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
1095MODULE_DESCRIPTION("Freescale MXS DCP Driver");
1096MODULE_LICENSE("GPL");
1097MODULE_ALIAS("platform:mxs-dcp");
1098