linux/drivers/crypto/mxs-dcp.c
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   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Freescale i.MX23/i.MX28 Data Co-Processor driver
   4 *
   5 * Copyright (C) 2013 Marek Vasut <marex@denx.de>
   6 */
   7
   8#include <linux/dma-mapping.h>
   9#include <linux/interrupt.h>
  10#include <linux/io.h>
  11#include <linux/kernel.h>
  12#include <linux/kthread.h>
  13#include <linux/module.h>
  14#include <linux/of.h>
  15#include <linux/platform_device.h>
  16#include <linux/stmp_device.h>
  17#include <linux/clk.h>
  18
  19#include <crypto/aes.h>
  20#include <crypto/sha1.h>
  21#include <crypto/sha2.h>
  22#include <crypto/internal/hash.h>
  23#include <crypto/internal/skcipher.h>
  24#include <crypto/scatterwalk.h>
  25
  26#define DCP_MAX_CHANS   4
  27#define DCP_BUF_SZ      PAGE_SIZE
  28#define DCP_SHA_PAY_SZ  64
  29
  30#define DCP_ALIGNMENT   64
  31
  32/*
  33 * Null hashes to align with hw behavior on imx6sl and ull
  34 * these are flipped for consistency with hw output
  35 */
  36static const uint8_t sha1_null_hash[] =
  37        "\x09\x07\xd8\xaf\x90\x18\x60\x95\xef\xbf"
  38        "\x55\x32\x0d\x4b\x6b\x5e\xee\xa3\x39\xda";
  39
  40static const uint8_t sha256_null_hash[] =
  41        "\x55\xb8\x52\x78\x1b\x99\x95\xa4"
  42        "\x4c\x93\x9b\x64\xe4\x41\xae\x27"
  43        "\x24\xb9\x6f\x99\xc8\xf4\xfb\x9a"
  44        "\x14\x1c\xfc\x98\x42\xc4\xb0\xe3";
  45
  46/* DCP DMA descriptor. */
  47struct dcp_dma_desc {
  48        uint32_t        next_cmd_addr;
  49        uint32_t        control0;
  50        uint32_t        control1;
  51        uint32_t        source;
  52        uint32_t        destination;
  53        uint32_t        size;
  54        uint32_t        payload;
  55        uint32_t        status;
  56};
  57
  58/* Coherent aligned block for bounce buffering. */
  59struct dcp_coherent_block {
  60        uint8_t                 aes_in_buf[DCP_BUF_SZ];
  61        uint8_t                 aes_out_buf[DCP_BUF_SZ];
  62        uint8_t                 sha_in_buf[DCP_BUF_SZ];
  63        uint8_t                 sha_out_buf[DCP_SHA_PAY_SZ];
  64
  65        uint8_t                 aes_key[2 * AES_KEYSIZE_128];
  66
  67        struct dcp_dma_desc     desc[DCP_MAX_CHANS];
  68};
  69
  70struct dcp {
  71        struct device                   *dev;
  72        void __iomem                    *base;
  73
  74        uint32_t                        caps;
  75
  76        struct dcp_coherent_block       *coh;
  77
  78        struct completion               completion[DCP_MAX_CHANS];
  79        spinlock_t                      lock[DCP_MAX_CHANS];
  80        struct task_struct              *thread[DCP_MAX_CHANS];
  81        struct crypto_queue             queue[DCP_MAX_CHANS];
  82        struct clk                      *dcp_clk;
  83};
  84
  85enum dcp_chan {
  86        DCP_CHAN_HASH_SHA       = 0,
  87        DCP_CHAN_CRYPTO         = 2,
  88};
  89
  90struct dcp_async_ctx {
  91        /* Common context */
  92        enum dcp_chan   chan;
  93        uint32_t        fill;
  94
  95        /* SHA Hash-specific context */
  96        struct mutex                    mutex;
  97        uint32_t                        alg;
  98        unsigned int                    hot:1;
  99
 100        /* Crypto-specific context */
 101        struct crypto_skcipher          *fallback;
 102        unsigned int                    key_len;
 103        uint8_t                         key[AES_KEYSIZE_128];
 104};
 105
 106struct dcp_aes_req_ctx {
 107        unsigned int    enc:1;
 108        unsigned int    ecb:1;
 109        struct skcipher_request fallback_req;   // keep at the end
 110};
 111
 112struct dcp_sha_req_ctx {
 113        unsigned int    init:1;
 114        unsigned int    fini:1;
 115};
 116
 117struct dcp_export_state {
 118        struct dcp_sha_req_ctx req_ctx;
 119        struct dcp_async_ctx async_ctx;
 120};
 121
 122/*
 123 * There can even be only one instance of the MXS DCP due to the
 124 * design of Linux Crypto API.
 125 */
 126static struct dcp *global_sdcp;
 127
 128/* DCP register layout. */
 129#define MXS_DCP_CTRL                            0x00
 130#define MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES     (1 << 23)
 131#define MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING     (1 << 22)
 132
 133#define MXS_DCP_STAT                            0x10
 134#define MXS_DCP_STAT_CLR                        0x18
 135#define MXS_DCP_STAT_IRQ_MASK                   0xf
 136
 137#define MXS_DCP_CHANNELCTRL                     0x20
 138#define MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK 0xff
 139
 140#define MXS_DCP_CAPABILITY1                     0x40
 141#define MXS_DCP_CAPABILITY1_SHA256              (4 << 16)
 142#define MXS_DCP_CAPABILITY1_SHA1                (1 << 16)
 143#define MXS_DCP_CAPABILITY1_AES128              (1 << 0)
 144
 145#define MXS_DCP_CONTEXT                         0x50
 146
 147#define MXS_DCP_CH_N_CMDPTR(n)                  (0x100 + ((n) * 0x40))
 148
 149#define MXS_DCP_CH_N_SEMA(n)                    (0x110 + ((n) * 0x40))
 150
 151#define MXS_DCP_CH_N_STAT(n)                    (0x120 + ((n) * 0x40))
 152#define MXS_DCP_CH_N_STAT_CLR(n)                (0x128 + ((n) * 0x40))
 153
 154/* DMA descriptor bits. */
 155#define MXS_DCP_CONTROL0_HASH_TERM              (1 << 13)
 156#define MXS_DCP_CONTROL0_HASH_INIT              (1 << 12)
 157#define MXS_DCP_CONTROL0_PAYLOAD_KEY            (1 << 11)
 158#define MXS_DCP_CONTROL0_CIPHER_ENCRYPT         (1 << 8)
 159#define MXS_DCP_CONTROL0_CIPHER_INIT            (1 << 9)
 160#define MXS_DCP_CONTROL0_ENABLE_HASH            (1 << 6)
 161#define MXS_DCP_CONTROL0_ENABLE_CIPHER          (1 << 5)
 162#define MXS_DCP_CONTROL0_DECR_SEMAPHORE         (1 << 1)
 163#define MXS_DCP_CONTROL0_INTERRUPT              (1 << 0)
 164
 165#define MXS_DCP_CONTROL1_HASH_SELECT_SHA256     (2 << 16)
 166#define MXS_DCP_CONTROL1_HASH_SELECT_SHA1       (0 << 16)
 167#define MXS_DCP_CONTROL1_CIPHER_MODE_CBC        (1 << 4)
 168#define MXS_DCP_CONTROL1_CIPHER_MODE_ECB        (0 << 4)
 169#define MXS_DCP_CONTROL1_CIPHER_SELECT_AES128   (0 << 0)
 170
 171static int mxs_dcp_start_dma(struct dcp_async_ctx *actx)
 172{
 173        int dma_err;
 174        struct dcp *sdcp = global_sdcp;
 175        const int chan = actx->chan;
 176        uint32_t stat;
 177        unsigned long ret;
 178        struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
 179        dma_addr_t desc_phys = dma_map_single(sdcp->dev, desc, sizeof(*desc),
 180                                              DMA_TO_DEVICE);
 181
 182        dma_err = dma_mapping_error(sdcp->dev, desc_phys);
 183        if (dma_err)
 184                return dma_err;
 185
 186        reinit_completion(&sdcp->completion[chan]);
 187
 188        /* Clear status register. */
 189        writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(chan));
 190
 191        /* Load the DMA descriptor. */
 192        writel(desc_phys, sdcp->base + MXS_DCP_CH_N_CMDPTR(chan));
 193
 194        /* Increment the semaphore to start the DMA transfer. */
 195        writel(1, sdcp->base + MXS_DCP_CH_N_SEMA(chan));
 196
 197        ret = wait_for_completion_timeout(&sdcp->completion[chan],
 198                                          msecs_to_jiffies(1000));
 199        if (!ret) {
 200                dev_err(sdcp->dev, "Channel %i timeout (DCP_STAT=0x%08x)\n",
 201                        chan, readl(sdcp->base + MXS_DCP_STAT));
 202                return -ETIMEDOUT;
 203        }
 204
 205        stat = readl(sdcp->base + MXS_DCP_CH_N_STAT(chan));
 206        if (stat & 0xff) {
 207                dev_err(sdcp->dev, "Channel %i error (CH_STAT=0x%08x)\n",
 208                        chan, stat);
 209                return -EINVAL;
 210        }
 211
 212        dma_unmap_single(sdcp->dev, desc_phys, sizeof(*desc), DMA_TO_DEVICE);
 213
 214        return 0;
 215}
 216
 217/*
 218 * Encryption (AES128)
 219 */
 220static int mxs_dcp_run_aes(struct dcp_async_ctx *actx,
 221                           struct skcipher_request *req, int init)
 222{
 223        dma_addr_t key_phys, src_phys, dst_phys;
 224        struct dcp *sdcp = global_sdcp;
 225        struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
 226        struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
 227        int ret;
 228
 229        key_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_key,
 230                                  2 * AES_KEYSIZE_128, DMA_TO_DEVICE);
 231        ret = dma_mapping_error(sdcp->dev, key_phys);
 232        if (ret)
 233                return ret;
 234
 235        src_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_in_buf,
 236                                  DCP_BUF_SZ, DMA_TO_DEVICE);
 237        ret = dma_mapping_error(sdcp->dev, src_phys);
 238        if (ret)
 239                goto err_src;
 240
 241        dst_phys = dma_map_single(sdcp->dev, sdcp->coh->aes_out_buf,
 242                                  DCP_BUF_SZ, DMA_FROM_DEVICE);
 243        ret = dma_mapping_error(sdcp->dev, dst_phys);
 244        if (ret)
 245                goto err_dst;
 246
 247        if (actx->fill % AES_BLOCK_SIZE) {
 248                dev_err(sdcp->dev, "Invalid block size!\n");
 249                ret = -EINVAL;
 250                goto aes_done_run;
 251        }
 252
 253        /* Fill in the DMA descriptor. */
 254        desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
 255                    MXS_DCP_CONTROL0_INTERRUPT |
 256                    MXS_DCP_CONTROL0_ENABLE_CIPHER;
 257
 258        /* Payload contains the key. */
 259        desc->control0 |= MXS_DCP_CONTROL0_PAYLOAD_KEY;
 260
 261        if (rctx->enc)
 262                desc->control0 |= MXS_DCP_CONTROL0_CIPHER_ENCRYPT;
 263        if (init)
 264                desc->control0 |= MXS_DCP_CONTROL0_CIPHER_INIT;
 265
 266        desc->control1 = MXS_DCP_CONTROL1_CIPHER_SELECT_AES128;
 267
 268        if (rctx->ecb)
 269                desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_ECB;
 270        else
 271                desc->control1 |= MXS_DCP_CONTROL1_CIPHER_MODE_CBC;
 272
 273        desc->next_cmd_addr = 0;
 274        desc->source = src_phys;
 275        desc->destination = dst_phys;
 276        desc->size = actx->fill;
 277        desc->payload = key_phys;
 278        desc->status = 0;
 279
 280        ret = mxs_dcp_start_dma(actx);
 281
 282aes_done_run:
 283        dma_unmap_single(sdcp->dev, dst_phys, DCP_BUF_SZ, DMA_FROM_DEVICE);
 284err_dst:
 285        dma_unmap_single(sdcp->dev, src_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
 286err_src:
 287        dma_unmap_single(sdcp->dev, key_phys, 2 * AES_KEYSIZE_128,
 288                         DMA_TO_DEVICE);
 289
 290        return ret;
 291}
 292
 293static int mxs_dcp_aes_block_crypt(struct crypto_async_request *arq)
 294{
 295        struct dcp *sdcp = global_sdcp;
 296
 297        struct skcipher_request *req = skcipher_request_cast(arq);
 298        struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
 299        struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
 300
 301        struct scatterlist *dst = req->dst;
 302        struct scatterlist *src = req->src;
 303        int dst_nents = sg_nents(dst);
 304
 305        const int out_off = DCP_BUF_SZ;
 306        uint8_t *in_buf = sdcp->coh->aes_in_buf;
 307        uint8_t *out_buf = sdcp->coh->aes_out_buf;
 308
 309        uint32_t dst_off = 0;
 310        uint8_t *src_buf = NULL;
 311        uint32_t last_out_len = 0;
 312
 313        uint8_t *key = sdcp->coh->aes_key;
 314
 315        int ret = 0;
 316        unsigned int i, len, clen, tlen = 0;
 317        int init = 0;
 318        bool limit_hit = false;
 319
 320        actx->fill = 0;
 321
 322        /* Copy the key from the temporary location. */
 323        memcpy(key, actx->key, actx->key_len);
 324
 325        if (!rctx->ecb) {
 326                /* Copy the CBC IV just past the key. */
 327                memcpy(key + AES_KEYSIZE_128, req->iv, AES_KEYSIZE_128);
 328                /* CBC needs the INIT set. */
 329                init = 1;
 330        } else {
 331                memset(key + AES_KEYSIZE_128, 0, AES_KEYSIZE_128);
 332        }
 333
 334        for_each_sg(req->src, src, sg_nents(src), i) {
 335                src_buf = sg_virt(src);
 336                len = sg_dma_len(src);
 337                tlen += len;
 338                limit_hit = tlen > req->cryptlen;
 339
 340                if (limit_hit)
 341                        len = req->cryptlen - (tlen - len);
 342
 343                do {
 344                        if (actx->fill + len > out_off)
 345                                clen = out_off - actx->fill;
 346                        else
 347                                clen = len;
 348
 349                        memcpy(in_buf + actx->fill, src_buf, clen);
 350                        len -= clen;
 351                        src_buf += clen;
 352                        actx->fill += clen;
 353
 354                        /*
 355                         * If we filled the buffer or this is the last SG,
 356                         * submit the buffer.
 357                         */
 358                        if (actx->fill == out_off || sg_is_last(src) ||
 359                            limit_hit) {
 360                                ret = mxs_dcp_run_aes(actx, req, init);
 361                                if (ret)
 362                                        return ret;
 363                                init = 0;
 364
 365                                sg_pcopy_from_buffer(dst, dst_nents, out_buf,
 366                                                     actx->fill, dst_off);
 367                                dst_off += actx->fill;
 368                                last_out_len = actx->fill;
 369                                actx->fill = 0;
 370                        }
 371                } while (len);
 372
 373                if (limit_hit)
 374                        break;
 375        }
 376
 377        /* Copy the IV for CBC for chaining */
 378        if (!rctx->ecb) {
 379                if (rctx->enc)
 380                        memcpy(req->iv, out_buf+(last_out_len-AES_BLOCK_SIZE),
 381                                AES_BLOCK_SIZE);
 382                else
 383                        memcpy(req->iv, in_buf+(last_out_len-AES_BLOCK_SIZE),
 384                                AES_BLOCK_SIZE);
 385        }
 386
 387        return ret;
 388}
 389
 390static int dcp_chan_thread_aes(void *data)
 391{
 392        struct dcp *sdcp = global_sdcp;
 393        const int chan = DCP_CHAN_CRYPTO;
 394
 395        struct crypto_async_request *backlog;
 396        struct crypto_async_request *arq;
 397
 398        int ret;
 399
 400        while (!kthread_should_stop()) {
 401                set_current_state(TASK_INTERRUPTIBLE);
 402
 403                spin_lock(&sdcp->lock[chan]);
 404                backlog = crypto_get_backlog(&sdcp->queue[chan]);
 405                arq = crypto_dequeue_request(&sdcp->queue[chan]);
 406                spin_unlock(&sdcp->lock[chan]);
 407
 408                if (!backlog && !arq) {
 409                        schedule();
 410                        continue;
 411                }
 412
 413                set_current_state(TASK_RUNNING);
 414
 415                if (backlog)
 416                        backlog->complete(backlog, -EINPROGRESS);
 417
 418                if (arq) {
 419                        ret = mxs_dcp_aes_block_crypt(arq);
 420                        arq->complete(arq, ret);
 421                }
 422        }
 423
 424        return 0;
 425}
 426
 427static int mxs_dcp_block_fallback(struct skcipher_request *req, int enc)
 428{
 429        struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req);
 430        struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
 431        struct dcp_async_ctx *ctx = crypto_skcipher_ctx(tfm);
 432        int ret;
 433
 434        skcipher_request_set_tfm(&rctx->fallback_req, ctx->fallback);
 435        skcipher_request_set_callback(&rctx->fallback_req, req->base.flags,
 436                                      req->base.complete, req->base.data);
 437        skcipher_request_set_crypt(&rctx->fallback_req, req->src, req->dst,
 438                                   req->cryptlen, req->iv);
 439
 440        if (enc)
 441                ret = crypto_skcipher_encrypt(&rctx->fallback_req);
 442        else
 443                ret = crypto_skcipher_decrypt(&rctx->fallback_req);
 444
 445        return ret;
 446}
 447
 448static int mxs_dcp_aes_enqueue(struct skcipher_request *req, int enc, int ecb)
 449{
 450        struct dcp *sdcp = global_sdcp;
 451        struct crypto_async_request *arq = &req->base;
 452        struct dcp_async_ctx *actx = crypto_tfm_ctx(arq->tfm);
 453        struct dcp_aes_req_ctx *rctx = skcipher_request_ctx(req);
 454        int ret;
 455
 456        if (unlikely(actx->key_len != AES_KEYSIZE_128))
 457                return mxs_dcp_block_fallback(req, enc);
 458
 459        rctx->enc = enc;
 460        rctx->ecb = ecb;
 461        actx->chan = DCP_CHAN_CRYPTO;
 462
 463        spin_lock(&sdcp->lock[actx->chan]);
 464        ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
 465        spin_unlock(&sdcp->lock[actx->chan]);
 466
 467        wake_up_process(sdcp->thread[actx->chan]);
 468
 469        return ret;
 470}
 471
 472static int mxs_dcp_aes_ecb_decrypt(struct skcipher_request *req)
 473{
 474        return mxs_dcp_aes_enqueue(req, 0, 1);
 475}
 476
 477static int mxs_dcp_aes_ecb_encrypt(struct skcipher_request *req)
 478{
 479        return mxs_dcp_aes_enqueue(req, 1, 1);
 480}
 481
 482static int mxs_dcp_aes_cbc_decrypt(struct skcipher_request *req)
 483{
 484        return mxs_dcp_aes_enqueue(req, 0, 0);
 485}
 486
 487static int mxs_dcp_aes_cbc_encrypt(struct skcipher_request *req)
 488{
 489        return mxs_dcp_aes_enqueue(req, 1, 0);
 490}
 491
 492static int mxs_dcp_aes_setkey(struct crypto_skcipher *tfm, const u8 *key,
 493                              unsigned int len)
 494{
 495        struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
 496
 497        /*
 498         * AES 128 is supposed by the hardware, store key into temporary
 499         * buffer and exit. We must use the temporary buffer here, since
 500         * there can still be an operation in progress.
 501         */
 502        actx->key_len = len;
 503        if (len == AES_KEYSIZE_128) {
 504                memcpy(actx->key, key, len);
 505                return 0;
 506        }
 507
 508        /*
 509         * If the requested AES key size is not supported by the hardware,
 510         * but is supported by in-kernel software implementation, we use
 511         * software fallback.
 512         */
 513        crypto_skcipher_clear_flags(actx->fallback, CRYPTO_TFM_REQ_MASK);
 514        crypto_skcipher_set_flags(actx->fallback,
 515                                  tfm->base.crt_flags & CRYPTO_TFM_REQ_MASK);
 516        return crypto_skcipher_setkey(actx->fallback, key, len);
 517}
 518
 519static int mxs_dcp_aes_fallback_init_tfm(struct crypto_skcipher *tfm)
 520{
 521        const char *name = crypto_tfm_alg_name(crypto_skcipher_tfm(tfm));
 522        struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
 523        struct crypto_skcipher *blk;
 524
 525        blk = crypto_alloc_skcipher(name, 0, CRYPTO_ALG_NEED_FALLBACK);
 526        if (IS_ERR(blk))
 527                return PTR_ERR(blk);
 528
 529        actx->fallback = blk;
 530        crypto_skcipher_set_reqsize(tfm, sizeof(struct dcp_aes_req_ctx) +
 531                                         crypto_skcipher_reqsize(blk));
 532        return 0;
 533}
 534
 535static void mxs_dcp_aes_fallback_exit_tfm(struct crypto_skcipher *tfm)
 536{
 537        struct dcp_async_ctx *actx = crypto_skcipher_ctx(tfm);
 538
 539        crypto_free_skcipher(actx->fallback);
 540}
 541
 542/*
 543 * Hashing (SHA1/SHA256)
 544 */
 545static int mxs_dcp_run_sha(struct ahash_request *req)
 546{
 547        struct dcp *sdcp = global_sdcp;
 548        int ret;
 549
 550        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 551        struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
 552        struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
 553        struct dcp_dma_desc *desc = &sdcp->coh->desc[actx->chan];
 554
 555        dma_addr_t digest_phys = 0;
 556        dma_addr_t buf_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_in_buf,
 557                                             DCP_BUF_SZ, DMA_TO_DEVICE);
 558
 559        ret = dma_mapping_error(sdcp->dev, buf_phys);
 560        if (ret)
 561                return ret;
 562
 563        /* Fill in the DMA descriptor. */
 564        desc->control0 = MXS_DCP_CONTROL0_DECR_SEMAPHORE |
 565                    MXS_DCP_CONTROL0_INTERRUPT |
 566                    MXS_DCP_CONTROL0_ENABLE_HASH;
 567        if (rctx->init)
 568                desc->control0 |= MXS_DCP_CONTROL0_HASH_INIT;
 569
 570        desc->control1 = actx->alg;
 571        desc->next_cmd_addr = 0;
 572        desc->source = buf_phys;
 573        desc->destination = 0;
 574        desc->size = actx->fill;
 575        desc->payload = 0;
 576        desc->status = 0;
 577
 578        /*
 579         * Align driver with hw behavior when generating null hashes
 580         */
 581        if (rctx->init && rctx->fini && desc->size == 0) {
 582                struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
 583                const uint8_t *sha_buf =
 584                        (actx->alg == MXS_DCP_CONTROL1_HASH_SELECT_SHA1) ?
 585                        sha1_null_hash : sha256_null_hash;
 586                memcpy(sdcp->coh->sha_out_buf, sha_buf, halg->digestsize);
 587                ret = 0;
 588                goto done_run;
 589        }
 590
 591        /* Set HASH_TERM bit for last transfer block. */
 592        if (rctx->fini) {
 593                digest_phys = dma_map_single(sdcp->dev, sdcp->coh->sha_out_buf,
 594                                             DCP_SHA_PAY_SZ, DMA_FROM_DEVICE);
 595                ret = dma_mapping_error(sdcp->dev, digest_phys);
 596                if (ret)
 597                        goto done_run;
 598
 599                desc->control0 |= MXS_DCP_CONTROL0_HASH_TERM;
 600                desc->payload = digest_phys;
 601        }
 602
 603        ret = mxs_dcp_start_dma(actx);
 604
 605        if (rctx->fini)
 606                dma_unmap_single(sdcp->dev, digest_phys, DCP_SHA_PAY_SZ,
 607                                 DMA_FROM_DEVICE);
 608
 609done_run:
 610        dma_unmap_single(sdcp->dev, buf_phys, DCP_BUF_SZ, DMA_TO_DEVICE);
 611
 612        return ret;
 613}
 614
 615static int dcp_sha_req_to_buf(struct crypto_async_request *arq)
 616{
 617        struct dcp *sdcp = global_sdcp;
 618
 619        struct ahash_request *req = ahash_request_cast(arq);
 620        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 621        struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
 622        struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
 623        struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
 624
 625        uint8_t *in_buf = sdcp->coh->sha_in_buf;
 626        uint8_t *out_buf = sdcp->coh->sha_out_buf;
 627
 628        struct scatterlist *src;
 629
 630        unsigned int i, len, clen, oft = 0;
 631        int ret;
 632
 633        int fin = rctx->fini;
 634        if (fin)
 635                rctx->fini = 0;
 636
 637        src = req->src;
 638        len = req->nbytes;
 639
 640        while (len) {
 641                if (actx->fill + len > DCP_BUF_SZ)
 642                        clen = DCP_BUF_SZ - actx->fill;
 643                else
 644                        clen = len;
 645
 646                scatterwalk_map_and_copy(in_buf + actx->fill, src, oft, clen,
 647                                         0);
 648
 649                len -= clen;
 650                oft += clen;
 651                actx->fill += clen;
 652
 653                /*
 654                 * If we filled the buffer and still have some
 655                 * more data, submit the buffer.
 656                 */
 657                if (len && actx->fill == DCP_BUF_SZ) {
 658                        ret = mxs_dcp_run_sha(req);
 659                        if (ret)
 660                                return ret;
 661                        actx->fill = 0;
 662                        rctx->init = 0;
 663                }
 664        }
 665
 666        if (fin) {
 667                rctx->fini = 1;
 668
 669                /* Submit whatever is left. */
 670                if (!req->result)
 671                        return -EINVAL;
 672
 673                ret = mxs_dcp_run_sha(req);
 674                if (ret)
 675                        return ret;
 676
 677                actx->fill = 0;
 678
 679                /* For some reason the result is flipped */
 680                for (i = 0; i < halg->digestsize; i++)
 681                        req->result[i] = out_buf[halg->digestsize - i - 1];
 682        }
 683
 684        return 0;
 685}
 686
 687static int dcp_chan_thread_sha(void *data)
 688{
 689        struct dcp *sdcp = global_sdcp;
 690        const int chan = DCP_CHAN_HASH_SHA;
 691
 692        struct crypto_async_request *backlog;
 693        struct crypto_async_request *arq;
 694        int ret;
 695
 696        while (!kthread_should_stop()) {
 697                set_current_state(TASK_INTERRUPTIBLE);
 698
 699                spin_lock(&sdcp->lock[chan]);
 700                backlog = crypto_get_backlog(&sdcp->queue[chan]);
 701                arq = crypto_dequeue_request(&sdcp->queue[chan]);
 702                spin_unlock(&sdcp->lock[chan]);
 703
 704                if (!backlog && !arq) {
 705                        schedule();
 706                        continue;
 707                }
 708
 709                set_current_state(TASK_RUNNING);
 710
 711                if (backlog)
 712                        backlog->complete(backlog, -EINPROGRESS);
 713
 714                if (arq) {
 715                        ret = dcp_sha_req_to_buf(arq);
 716                        arq->complete(arq, ret);
 717                }
 718        }
 719
 720        return 0;
 721}
 722
 723static int dcp_sha_init(struct ahash_request *req)
 724{
 725        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 726        struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
 727
 728        struct hash_alg_common *halg = crypto_hash_alg_common(tfm);
 729
 730        /*
 731         * Start hashing session. The code below only inits the
 732         * hashing session context, nothing more.
 733         */
 734        memset(actx, 0, sizeof(*actx));
 735
 736        if (strcmp(halg->base.cra_name, "sha1") == 0)
 737                actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA1;
 738        else
 739                actx->alg = MXS_DCP_CONTROL1_HASH_SELECT_SHA256;
 740
 741        actx->fill = 0;
 742        actx->hot = 0;
 743        actx->chan = DCP_CHAN_HASH_SHA;
 744
 745        mutex_init(&actx->mutex);
 746
 747        return 0;
 748}
 749
 750static int dcp_sha_update_fx(struct ahash_request *req, int fini)
 751{
 752        struct dcp *sdcp = global_sdcp;
 753
 754        struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
 755        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 756        struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
 757
 758        int ret;
 759
 760        /*
 761         * Ignore requests that have no data in them and are not
 762         * the trailing requests in the stream of requests.
 763         */
 764        if (!req->nbytes && !fini)
 765                return 0;
 766
 767        mutex_lock(&actx->mutex);
 768
 769        rctx->fini = fini;
 770
 771        if (!actx->hot) {
 772                actx->hot = 1;
 773                rctx->init = 1;
 774        }
 775
 776        spin_lock(&sdcp->lock[actx->chan]);
 777        ret = crypto_enqueue_request(&sdcp->queue[actx->chan], &req->base);
 778        spin_unlock(&sdcp->lock[actx->chan]);
 779
 780        wake_up_process(sdcp->thread[actx->chan]);
 781        mutex_unlock(&actx->mutex);
 782
 783        return ret;
 784}
 785
 786static int dcp_sha_update(struct ahash_request *req)
 787{
 788        return dcp_sha_update_fx(req, 0);
 789}
 790
 791static int dcp_sha_final(struct ahash_request *req)
 792{
 793        ahash_request_set_crypt(req, NULL, req->result, 0);
 794        req->nbytes = 0;
 795        return dcp_sha_update_fx(req, 1);
 796}
 797
 798static int dcp_sha_finup(struct ahash_request *req)
 799{
 800        return dcp_sha_update_fx(req, 1);
 801}
 802
 803static int dcp_sha_digest(struct ahash_request *req)
 804{
 805        int ret;
 806
 807        ret = dcp_sha_init(req);
 808        if (ret)
 809                return ret;
 810
 811        return dcp_sha_finup(req);
 812}
 813
 814static int dcp_sha_import(struct ahash_request *req, const void *in)
 815{
 816        struct dcp_sha_req_ctx *rctx = ahash_request_ctx(req);
 817        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 818        struct dcp_async_ctx *actx = crypto_ahash_ctx(tfm);
 819        const struct dcp_export_state *export = in;
 820
 821        memset(rctx, 0, sizeof(struct dcp_sha_req_ctx));
 822        memset(actx, 0, sizeof(struct dcp_async_ctx));
 823        memcpy(rctx, &export->req_ctx, sizeof(struct dcp_sha_req_ctx));
 824        memcpy(actx, &export->async_ctx, sizeof(struct dcp_async_ctx));
 825
 826        return 0;
 827}
 828
 829static int dcp_sha_export(struct ahash_request *req, void *out)
 830{
 831        struct dcp_sha_req_ctx *rctx_state = ahash_request_ctx(req);
 832        struct crypto_ahash *tfm = crypto_ahash_reqtfm(req);
 833        struct dcp_async_ctx *actx_state = crypto_ahash_ctx(tfm);
 834        struct dcp_export_state *export = out;
 835
 836        memcpy(&export->req_ctx, rctx_state, sizeof(struct dcp_sha_req_ctx));
 837        memcpy(&export->async_ctx, actx_state, sizeof(struct dcp_async_ctx));
 838
 839        return 0;
 840}
 841
 842static int dcp_sha_cra_init(struct crypto_tfm *tfm)
 843{
 844        crypto_ahash_set_reqsize(__crypto_ahash_cast(tfm),
 845                                 sizeof(struct dcp_sha_req_ctx));
 846        return 0;
 847}
 848
 849static void dcp_sha_cra_exit(struct crypto_tfm *tfm)
 850{
 851}
 852
 853/* AES 128 ECB and AES 128 CBC */
 854static struct skcipher_alg dcp_aes_algs[] = {
 855        {
 856                .base.cra_name          = "ecb(aes)",
 857                .base.cra_driver_name   = "ecb-aes-dcp",
 858                .base.cra_priority      = 400,
 859                .base.cra_alignmask     = 15,
 860                .base.cra_flags         = CRYPTO_ALG_ASYNC |
 861                                          CRYPTO_ALG_NEED_FALLBACK,
 862                .base.cra_blocksize     = AES_BLOCK_SIZE,
 863                .base.cra_ctxsize       = sizeof(struct dcp_async_ctx),
 864                .base.cra_module        = THIS_MODULE,
 865
 866                .min_keysize            = AES_MIN_KEY_SIZE,
 867                .max_keysize            = AES_MAX_KEY_SIZE,
 868                .setkey                 = mxs_dcp_aes_setkey,
 869                .encrypt                = mxs_dcp_aes_ecb_encrypt,
 870                .decrypt                = mxs_dcp_aes_ecb_decrypt,
 871                .init                   = mxs_dcp_aes_fallback_init_tfm,
 872                .exit                   = mxs_dcp_aes_fallback_exit_tfm,
 873        }, {
 874                .base.cra_name          = "cbc(aes)",
 875                .base.cra_driver_name   = "cbc-aes-dcp",
 876                .base.cra_priority      = 400,
 877                .base.cra_alignmask     = 15,
 878                .base.cra_flags         = CRYPTO_ALG_ASYNC |
 879                                          CRYPTO_ALG_NEED_FALLBACK,
 880                .base.cra_blocksize     = AES_BLOCK_SIZE,
 881                .base.cra_ctxsize       = sizeof(struct dcp_async_ctx),
 882                .base.cra_module        = THIS_MODULE,
 883
 884                .min_keysize            = AES_MIN_KEY_SIZE,
 885                .max_keysize            = AES_MAX_KEY_SIZE,
 886                .setkey                 = mxs_dcp_aes_setkey,
 887                .encrypt                = mxs_dcp_aes_cbc_encrypt,
 888                .decrypt                = mxs_dcp_aes_cbc_decrypt,
 889                .ivsize                 = AES_BLOCK_SIZE,
 890                .init                   = mxs_dcp_aes_fallback_init_tfm,
 891                .exit                   = mxs_dcp_aes_fallback_exit_tfm,
 892        },
 893};
 894
 895/* SHA1 */
 896static struct ahash_alg dcp_sha1_alg = {
 897        .init   = dcp_sha_init,
 898        .update = dcp_sha_update,
 899        .final  = dcp_sha_final,
 900        .finup  = dcp_sha_finup,
 901        .digest = dcp_sha_digest,
 902        .import = dcp_sha_import,
 903        .export = dcp_sha_export,
 904        .halg   = {
 905                .digestsize     = SHA1_DIGEST_SIZE,
 906                .statesize      = sizeof(struct dcp_export_state),
 907                .base           = {
 908                        .cra_name               = "sha1",
 909                        .cra_driver_name        = "sha1-dcp",
 910                        .cra_priority           = 400,
 911                        .cra_alignmask          = 63,
 912                        .cra_flags              = CRYPTO_ALG_ASYNC,
 913                        .cra_blocksize          = SHA1_BLOCK_SIZE,
 914                        .cra_ctxsize            = sizeof(struct dcp_async_ctx),
 915                        .cra_module             = THIS_MODULE,
 916                        .cra_init               = dcp_sha_cra_init,
 917                        .cra_exit               = dcp_sha_cra_exit,
 918                },
 919        },
 920};
 921
 922/* SHA256 */
 923static struct ahash_alg dcp_sha256_alg = {
 924        .init   = dcp_sha_init,
 925        .update = dcp_sha_update,
 926        .final  = dcp_sha_final,
 927        .finup  = dcp_sha_finup,
 928        .digest = dcp_sha_digest,
 929        .import = dcp_sha_import,
 930        .export = dcp_sha_export,
 931        .halg   = {
 932                .digestsize     = SHA256_DIGEST_SIZE,
 933                .statesize      = sizeof(struct dcp_export_state),
 934                .base           = {
 935                        .cra_name               = "sha256",
 936                        .cra_driver_name        = "sha256-dcp",
 937                        .cra_priority           = 400,
 938                        .cra_alignmask          = 63,
 939                        .cra_flags              = CRYPTO_ALG_ASYNC,
 940                        .cra_blocksize          = SHA256_BLOCK_SIZE,
 941                        .cra_ctxsize            = sizeof(struct dcp_async_ctx),
 942                        .cra_module             = THIS_MODULE,
 943                        .cra_init               = dcp_sha_cra_init,
 944                        .cra_exit               = dcp_sha_cra_exit,
 945                },
 946        },
 947};
 948
 949static irqreturn_t mxs_dcp_irq(int irq, void *context)
 950{
 951        struct dcp *sdcp = context;
 952        uint32_t stat;
 953        int i;
 954
 955        stat = readl(sdcp->base + MXS_DCP_STAT);
 956        stat &= MXS_DCP_STAT_IRQ_MASK;
 957        if (!stat)
 958                return IRQ_NONE;
 959
 960        /* Clear the interrupts. */
 961        writel(stat, sdcp->base + MXS_DCP_STAT_CLR);
 962
 963        /* Complete the DMA requests that finished. */
 964        for (i = 0; i < DCP_MAX_CHANS; i++)
 965                if (stat & (1 << i))
 966                        complete(&sdcp->completion[i]);
 967
 968        return IRQ_HANDLED;
 969}
 970
 971static int mxs_dcp_probe(struct platform_device *pdev)
 972{
 973        struct device *dev = &pdev->dev;
 974        struct dcp *sdcp = NULL;
 975        int i, ret;
 976        int dcp_vmi_irq, dcp_irq;
 977
 978        if (global_sdcp) {
 979                dev_err(dev, "Only one DCP instance allowed!\n");
 980                return -ENODEV;
 981        }
 982
 983        dcp_vmi_irq = platform_get_irq(pdev, 0);
 984        if (dcp_vmi_irq < 0)
 985                return dcp_vmi_irq;
 986
 987        dcp_irq = platform_get_irq(pdev, 1);
 988        if (dcp_irq < 0)
 989                return dcp_irq;
 990
 991        sdcp = devm_kzalloc(dev, sizeof(*sdcp), GFP_KERNEL);
 992        if (!sdcp)
 993                return -ENOMEM;
 994
 995        sdcp->dev = dev;
 996        sdcp->base = devm_platform_ioremap_resource(pdev, 0);
 997        if (IS_ERR(sdcp->base))
 998                return PTR_ERR(sdcp->base);
 999
1000
1001        ret = devm_request_irq(dev, dcp_vmi_irq, mxs_dcp_irq, 0,
1002                               "dcp-vmi-irq", sdcp);
1003        if (ret) {
1004                dev_err(dev, "Failed to claim DCP VMI IRQ!\n");
1005                return ret;
1006        }
1007
1008        ret = devm_request_irq(dev, dcp_irq, mxs_dcp_irq, 0,
1009                               "dcp-irq", sdcp);
1010        if (ret) {
1011                dev_err(dev, "Failed to claim DCP IRQ!\n");
1012                return ret;
1013        }
1014
1015        /* Allocate coherent helper block. */
1016        sdcp->coh = devm_kzalloc(dev, sizeof(*sdcp->coh) + DCP_ALIGNMENT,
1017                                   GFP_KERNEL);
1018        if (!sdcp->coh)
1019                return -ENOMEM;
1020
1021        /* Re-align the structure so it fits the DCP constraints. */
1022        sdcp->coh = PTR_ALIGN(sdcp->coh, DCP_ALIGNMENT);
1023
1024        /* DCP clock is optional, only used on some SOCs */
1025        sdcp->dcp_clk = devm_clk_get(dev, "dcp");
1026        if (IS_ERR(sdcp->dcp_clk)) {
1027                if (sdcp->dcp_clk != ERR_PTR(-ENOENT))
1028                        return PTR_ERR(sdcp->dcp_clk);
1029                sdcp->dcp_clk = NULL;
1030        }
1031        ret = clk_prepare_enable(sdcp->dcp_clk);
1032        if (ret)
1033                return ret;
1034
1035        /* Restart the DCP block. */
1036        ret = stmp_reset_block(sdcp->base);
1037        if (ret) {
1038                dev_err(dev, "Failed reset\n");
1039                goto err_disable_unprepare_clk;
1040        }
1041
1042        /* Initialize control register. */
1043        writel(MXS_DCP_CTRL_GATHER_RESIDUAL_WRITES |
1044               MXS_DCP_CTRL_ENABLE_CONTEXT_CACHING | 0xf,
1045               sdcp->base + MXS_DCP_CTRL);
1046
1047        /* Enable all DCP DMA channels. */
1048        writel(MXS_DCP_CHANNELCTRL_ENABLE_CHANNEL_MASK,
1049               sdcp->base + MXS_DCP_CHANNELCTRL);
1050
1051        /*
1052         * We do not enable context switching. Give the context buffer a
1053         * pointer to an illegal address so if context switching is
1054         * inadvertantly enabled, the DCP will return an error instead of
1055         * trashing good memory. The DCP DMA cannot access ROM, so any ROM
1056         * address will do.
1057         */
1058        writel(0xffff0000, sdcp->base + MXS_DCP_CONTEXT);
1059        for (i = 0; i < DCP_MAX_CHANS; i++)
1060                writel(0xffffffff, sdcp->base + MXS_DCP_CH_N_STAT_CLR(i));
1061        writel(0xffffffff, sdcp->base + MXS_DCP_STAT_CLR);
1062
1063        global_sdcp = sdcp;
1064
1065        platform_set_drvdata(pdev, sdcp);
1066
1067        for (i = 0; i < DCP_MAX_CHANS; i++) {
1068                spin_lock_init(&sdcp->lock[i]);
1069                init_completion(&sdcp->completion[i]);
1070                crypto_init_queue(&sdcp->queue[i], 50);
1071        }
1072
1073        /* Create the SHA and AES handler threads. */
1074        sdcp->thread[DCP_CHAN_HASH_SHA] = kthread_run(dcp_chan_thread_sha,
1075                                                      NULL, "mxs_dcp_chan/sha");
1076        if (IS_ERR(sdcp->thread[DCP_CHAN_HASH_SHA])) {
1077                dev_err(dev, "Error starting SHA thread!\n");
1078                ret = PTR_ERR(sdcp->thread[DCP_CHAN_HASH_SHA]);
1079                goto err_disable_unprepare_clk;
1080        }
1081
1082        sdcp->thread[DCP_CHAN_CRYPTO] = kthread_run(dcp_chan_thread_aes,
1083                                                    NULL, "mxs_dcp_chan/aes");
1084        if (IS_ERR(sdcp->thread[DCP_CHAN_CRYPTO])) {
1085                dev_err(dev, "Error starting SHA thread!\n");
1086                ret = PTR_ERR(sdcp->thread[DCP_CHAN_CRYPTO]);
1087                goto err_destroy_sha_thread;
1088        }
1089
1090        /* Register the various crypto algorithms. */
1091        sdcp->caps = readl(sdcp->base + MXS_DCP_CAPABILITY1);
1092
1093        if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128) {
1094                ret = crypto_register_skciphers(dcp_aes_algs,
1095                                                ARRAY_SIZE(dcp_aes_algs));
1096                if (ret) {
1097                        /* Failed to register algorithm. */
1098                        dev_err(dev, "Failed to register AES crypto!\n");
1099                        goto err_destroy_aes_thread;
1100                }
1101        }
1102
1103        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1) {
1104                ret = crypto_register_ahash(&dcp_sha1_alg);
1105                if (ret) {
1106                        dev_err(dev, "Failed to register %s hash!\n",
1107                                dcp_sha1_alg.halg.base.cra_name);
1108                        goto err_unregister_aes;
1109                }
1110        }
1111
1112        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256) {
1113                ret = crypto_register_ahash(&dcp_sha256_alg);
1114                if (ret) {
1115                        dev_err(dev, "Failed to register %s hash!\n",
1116                                dcp_sha256_alg.halg.base.cra_name);
1117                        goto err_unregister_sha1;
1118                }
1119        }
1120
1121        return 0;
1122
1123err_unregister_sha1:
1124        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1125                crypto_unregister_ahash(&dcp_sha1_alg);
1126
1127err_unregister_aes:
1128        if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1129                crypto_unregister_skciphers(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1130
1131err_destroy_aes_thread:
1132        kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1133
1134err_destroy_sha_thread:
1135        kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1136
1137err_disable_unprepare_clk:
1138        clk_disable_unprepare(sdcp->dcp_clk);
1139
1140        return ret;
1141}
1142
1143static int mxs_dcp_remove(struct platform_device *pdev)
1144{
1145        struct dcp *sdcp = platform_get_drvdata(pdev);
1146
1147        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA256)
1148                crypto_unregister_ahash(&dcp_sha256_alg);
1149
1150        if (sdcp->caps & MXS_DCP_CAPABILITY1_SHA1)
1151                crypto_unregister_ahash(&dcp_sha1_alg);
1152
1153        if (sdcp->caps & MXS_DCP_CAPABILITY1_AES128)
1154                crypto_unregister_skciphers(dcp_aes_algs, ARRAY_SIZE(dcp_aes_algs));
1155
1156        kthread_stop(sdcp->thread[DCP_CHAN_HASH_SHA]);
1157        kthread_stop(sdcp->thread[DCP_CHAN_CRYPTO]);
1158
1159        clk_disable_unprepare(sdcp->dcp_clk);
1160
1161        platform_set_drvdata(pdev, NULL);
1162
1163        global_sdcp = NULL;
1164
1165        return 0;
1166}
1167
1168static const struct of_device_id mxs_dcp_dt_ids[] = {
1169        { .compatible = "fsl,imx23-dcp", .data = NULL, },
1170        { .compatible = "fsl,imx28-dcp", .data = NULL, },
1171        { /* sentinel */ }
1172};
1173
1174MODULE_DEVICE_TABLE(of, mxs_dcp_dt_ids);
1175
1176static struct platform_driver mxs_dcp_driver = {
1177        .probe  = mxs_dcp_probe,
1178        .remove = mxs_dcp_remove,
1179        .driver = {
1180                .name           = "mxs-dcp",
1181                .of_match_table = mxs_dcp_dt_ids,
1182        },
1183};
1184
1185module_platform_driver(mxs_dcp_driver);
1186
1187MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
1188MODULE_DESCRIPTION("Freescale MXS DCP Driver");
1189MODULE_LICENSE("GPL");
1190MODULE_ALIAS("platform:mxs-dcp");
1191