drivers/dma/dmatest.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * DMA Engine test module
   4  *
   5  * Copyright (C) 2007 Atmel Corporation
   6  * Copyright (C) 2013 Intel Corporation
   7  */
   8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
   9
  10 #include <linux/delay.h>
  11 #include <linux/dma-mapping.h>
  12 #include <linux/dmaengine.h>
  13 #include <linux/freezer.h>
  14 #include <linux/init.h>
  15 #include <linux/kthread.h>
  16 #include <linux/sched/task.h>
  17 #include <linux/module.h>
  18 #include <linux/moduleparam.h>
  19 #include <linux/random.h>
  20 #include <linux/slab.h>
  21 #include <linux/wait.h>
  22
  23 static unsigned int test_buf_size = 16384;
  24 module_param(test_buf_size, uint, S_IRUGO | S_IWUSR);
  25 MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer");
  26
  27 static char test_device[32];
  28 module_param_string(device, test_device, sizeof(test_device),
  29                 S_IRUGO | S_IWUSR);
  30 MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)");
  31
  32 static unsigned int threads_per_chan = 1;
  33 module_param(threads_per_chan, uint, S_IRUGO | S_IWUSR);
  34 MODULE_PARM_DESC(threads_per_chan,
  35                 "Number of threads to start per channel (default: 1)");
  36
  37 static unsigned int max_channels;
  38 module_param(max_channels, uint, S_IRUGO | S_IWUSR);
  39 MODULE_PARM_DESC(max_channels,
  40                 "Maximum number of channels to use (default: all)");
  41
  42 static unsigned int iterations;
  43 module_param(iterations, uint, S_IRUGO | S_IWUSR);
  44 MODULE_PARM_DESC(iterations,
  45                 "Iterations before stopping test (default: infinite)");
  46
  47 static unsigned int dmatest;
  48 module_param(dmatest, uint, S_IRUGO | S_IWUSR);
  49 MODULE_PARM_DESC(dmatest,
  50                 "dmatest 0-memcpy 1-memset (default: 0)");
  51
  52 static unsigned int xor_sources = 3;
  53 module_param(xor_sources, uint, S_IRUGO | S_IWUSR);
  54 MODULE_PARM_DESC(xor_sources,
  55                 "Number of xor source buffers (default: 3)");
  56
  57 static unsigned int pq_sources = 3;
  58 module_param(pq_sources, uint, S_IRUGO | S_IWUSR);
  59 MODULE_PARM_DESC(pq_sources,
  60                 "Number of p+q source buffers (default: 3)");
  61
  62 static int timeout = 3000;
  63 module_param(timeout, int, S_IRUGO | S_IWUSR);
  64 MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
  65                  "Pass -1 for infinite timeout");
  66
  67 static bool noverify;
  68 module_param(noverify, bool, S_IRUGO | S_IWUSR);
  69 MODULE_PARM_DESC(noverify, "Disable data verification (default: verify)");
  70
  71 static bool norandom;
  72 module_param(norandom, bool, 0644);
  73 MODULE_PARM_DESC(norandom, "Disable random offset setup (default: random)");
  74
  75 static bool verbose;
  76 module_param(verbose, bool, S_IRUGO | S_IWUSR);
  77 MODULE_PARM_DESC(verbose, "Enable \"success\" result messages (default: off)");
  78
  79 static int alignment = -1;
  80 module_param(alignment, int, 0644);
  81 MODULE_PARM_DESC(alignment, "Custom data address alignment taken as 2^(alignment) (default: not used (-1))");
  82
  83 static unsigned int transfer_size;
  84 module_param(transfer_size, uint, 0644);
  85 MODULE_PARM_DESC(transfer_size, "Optional custom transfer size in bytes (default: not used (0))");
  86
  87 static bool polled;
  88 module_param(polled, bool, S_IRUGO | S_IWUSR);
  89 MODULE_PARM_DESC(polled, "Use polling for completion instead of interrupts");
  90
  91 /**
  92  * struct dmatest_params - test parameters.
  93  * @buf_size:           size of the memcpy test buffer
  94  * @channel:            bus ID of the channel to test
  95  * @device:             bus ID of the DMA Engine to test
  96  * @threads_per_chan:   number of threads to start per channel
  97  * @max_channels:       maximum number of channels to use
  98  * @iterations:         iterations before stopping test
  99  * @xor_sources:        number of xor source buffers
 100  * @pq_sources:         number of p+q source buffers
 101  * @timeout:            transfer timeout in msec, -1 for infinite timeout
 102  * @noverify:           disable data verification
 103  * @norandom:           disable random offset setup
 104  * @alignment:          custom data address alignment taken as 2^alignment
 105  * @transfer_size:      custom transfer size in bytes
 106  * @polled:             use polling for completion instead of interrupts
 107  */
 108 struct dmatest_params {
 109         unsigned int    buf_size;
 110         char            channel[20];
 111         char            device[32];
 112         unsigned int    threads_per_chan;
 113         unsigned int    max_channels;
 114         unsigned int    iterations;
 115         unsigned int    xor_sources;
 116         unsigned int    pq_sources;
 117         int             timeout;
 118         bool            noverify;
 119         bool            norandom;
 120         int             alignment;
 121         unsigned int    transfer_size;
 122         bool            polled;
 123 };
 124
 125 /**
 126  * struct dmatest_info - test information.
 127  * @params:             test parameters
 128  * @channels:           channels under test
 129  * @nr_channels:        number of channels under test
 130  * @lock:               access protection to the fields of this structure
 131  * @did_init:           module has been initialized completely
 132  */
 133 static struct dmatest_info {
 134         /* Test parameters */
 135         struct dmatest_params   params;
 136
 137         /* Internal state */
 138         struct list_head        channels;
 139         unsigned int            nr_channels;
 140         struct mutex            lock;
 141         bool                    did_init;
 142 } test_info = {
 143         .channels = LIST_HEAD_INIT(test_info.channels),
 144         .lock = __MUTEX_INITIALIZER(test_info.lock),
 145 };
 146
 147 static int dmatest_run_set(const char *val, const struct kernel_param *kp);
 148 static int dmatest_run_get(char *val, const struct kernel_param *kp);
 149 static const struct kernel_param_ops run_ops = {
 150         .set = dmatest_run_set,
 151         .get = dmatest_run_get,
 152 };
 153 static bool dmatest_run;
 154 module_param_cb(run, &run_ops, &dmatest_run, S_IRUGO | S_IWUSR);
 155 MODULE_PARM_DESC(run, "Run the test (default: false)");
 156
 157 static int dmatest_chan_set(const char *val, const struct kernel_param *kp);
 158 static int dmatest_chan_get(char *val, const struct kernel_param *kp);
 159 static const struct kernel_param_ops multi_chan_ops = {
 160         .set = dmatest_chan_set,
 161         .get = dmatest_chan_get,
 162 };
 163
 164 static char test_channel[20];
 165 static struct kparam_string newchan_kps = {
 166         .string = test_channel,
 167         .maxlen = 20,
 168 };
 169 module_param_cb(channel, &multi_chan_ops, &newchan_kps, 0644);
 170 MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)");
 171
 172 static int dmatest_test_list_get(char *val, const struct kernel_param *kp);
 173 static const struct kernel_param_ops test_list_ops = {
 174         .get = dmatest_test_list_get,
 175 };
 176 module_param_cb(test_list, &test_list_ops, NULL, 0444);
 177 MODULE_PARM_DESC(test_list, "Print current test list");
 178
 179 /* Maximum amount of mismatched bytes in buffer to print */
 180 #define MAX_ERROR_COUNT         32
 181
 182 /*
 183  * Initialization patterns. All bytes in the source buffer has bit 7
 184  * set, all bytes in the destination buffer has bit 7 cleared.
 185  *
 186  * Bit 6 is set for all bytes which are to be copied by the DMA
 187  * engine. Bit 5 is set for all bytes which are to be overwritten by
 188  * the DMA engine.
 189  *
 190  * The remaining bits are the inverse of a counter which increments by
 191  * one for each byte address.
 192  */
 193 #define PATTERN_SRC             0x80
 194 #define PATTERN_DST             0x00
 195 #define PATTERN_COPY            0x40
 196 #define PATTERN_OVERWRITE       0x20
 197 #define PATTERN_COUNT_MASK      0x1f
 198 #define PATTERN_MEMSET_IDX      0x01
 199
 200 /* Fixed point arithmetic ops */
 201 #define FIXPT_SHIFT             8
 202 #define FIXPNT_MASK             0xFF
 203 #define FIXPT_TO_INT(a) ((a) >> FIXPT_SHIFT)
 204 #define INT_TO_FIXPT(a) ((a) << FIXPT_SHIFT)
 205 #define FIXPT_GET_FRAC(a)       ((((a) & FIXPNT_MASK) * 100) >> FIXPT_SHIFT)
 206
 207 /* poor man's completion - we want to use wait_event_freezable() on it */
 208 struct dmatest_done {
 209         bool                    done;
 210         wait_queue_head_t       *wait;
 211 };
 212
 213 struct dmatest_data {
 214         u8              **raw;
 215         u8              **aligned;
 216         unsigned int    cnt;
 217         unsigned int    off;
 218 };
 219
 220 struct dmatest_thread {
 221         struct list_head        node;
 222         struct dmatest_info     *info;
 223         struct task_struct      *task;
 224         struct dma_chan         *chan;
 225         struct dmatest_data     src;
 226         struct dmatest_data     dst;
 227         enum dma_transaction_type type;
 228         wait_queue_head_t done_wait;
 229         struct dmatest_done test_done;
 230         bool                    done;
 231         bool                    pending;
 232 };
 233
 234 struct dmatest_chan {
 235         struct list_head        node;
 236         struct dma_chan         *chan;
 237         struct list_head        threads;
 238 };
 239
 240 static DECLARE_WAIT_QUEUE_HEAD(thread_wait);
 241 static bool wait;
 242
 243 static bool is_threaded_test_run(struct dmatest_info *info)
 244 {
 245         struct dmatest_chan *dtc;
 246
 247         list_for_each_entry(dtc, &info->channels, node) {
 248                 struct dmatest_thread *thread;
 249
 250                 list_for_each_entry(thread, &dtc->threads, node) {
 251                         if (!thread->done && !thread->pending)
 252                                 return true;
 253                 }
 254         }
 255
 256         return false;
 257 }
 258
 259 static bool is_threaded_test_pending(struct dmatest_info *info)
 260 {
 261         struct dmatest_chan *dtc;
 262
 263         list_for_each_entry(dtc, &info->channels, node) {
 264                 struct dmatest_thread *thread;
 265
 266                 list_for_each_entry(thread, &dtc->threads, node) {
 267                         if (thread->pending)
 268                                 return true;
 269                 }
 270         }
 271
 272         return false;
 273 }
 274
 275 static int dmatest_wait_get(char *val, const struct kernel_param *kp)
 276 {
 277         struct dmatest_info *info = &test_info;
 278         struct dmatest_params *params = &info->params;
 279
 280         if (params->iterations)
 281                 wait_event(thread_wait, !is_threaded_test_run(info));
 282         wait = true;
 283         return param_get_bool(val, kp);
 284 }
 285
 286 static const struct kernel_param_ops wait_ops = {
 287         .get = dmatest_wait_get,
 288         .set = param_set_bool,
 289 };
 290 module_param_cb(wait, &wait_ops, &wait, S_IRUGO);
 291 MODULE_PARM_DESC(wait, "Wait for tests to complete (default: false)");
 292
 293 static bool dmatest_match_channel(struct dmatest_params *params,
 294                 struct dma_chan *chan)
 295 {
 296         if (params->channel[0] == '\0')
 297                 return true;
 298         return strcmp(dma_chan_name(chan), params->channel) == 0;
 299 }
 300
 301 static bool dmatest_match_device(struct dmatest_params *params,
 302                 struct dma_device *device)
 303 {
 304         if (params->device[0] == '\0')
 305                 return true;
 306         return strcmp(dev_name(device->dev), params->device) == 0;
 307 }
 308
 309 static unsigned long dmatest_random(void)
 310 {
 311         unsigned long buf;
 312
 313         prandom_bytes(&buf, sizeof(buf));
 314         return buf;
 315 }
 316
 317 static inline u8 gen_inv_idx(u8 index, bool is_memset)
 318 {
 319         u8 val = is_memset ? PATTERN_MEMSET_IDX : index;
 320
 321         return ~val & PATTERN_COUNT_MASK;
 322 }
 323
 324 static inline u8 gen_src_value(u8 index, bool is_memset)
 325 {
 326         return PATTERN_SRC | gen_inv_idx(index, is_memset);
 327 }
 328
 329 static inline u8 gen_dst_value(u8 index, bool is_memset)
 330 {
 331         return PATTERN_DST | gen_inv_idx(index, is_memset);
 332 }
 333
 334 static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len,
 335                 unsigned int buf_size, bool is_memset)
 336 {
 337         unsigned int i;
 338         u8 *buf;
 339
 340         for (; (buf = *bufs); bufs++) {
 341                 for (i = 0; i < start; i++)
 342                         buf[i] = gen_src_value(i, is_memset);
 343                 for ( ; i < start + len; i++)
 344                         buf[i] = gen_src_value(i, is_memset) | PATTERN_COPY;
 345                 for ( ; i < buf_size; i++)
 346                         buf[i] = gen_src_value(i, is_memset);
 347                 buf++;
 348         }
 349 }
 350
 351 static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len,
 352                 unsigned int buf_size, bool is_memset)
 353 {
 354         unsigned int i;
 355         u8 *buf;
 356
 357         for (; (buf = *bufs); bufs++) {
 358                 for (i = 0; i < start; i++)
 359                         buf[i] = gen_dst_value(i, is_memset);
 360                 for ( ; i < start + len; i++)
 361                         buf[i] = gen_dst_value(i, is_memset) |
 362                                                 PATTERN_OVERWRITE;
 363                 for ( ; i < buf_size; i++)
 364                         buf[i] = gen_dst_value(i, is_memset);
 365         }
 366 }
 367
 368 static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index,
 369                 unsigned int counter, bool is_srcbuf, bool is_memset)
 370 {
 371         u8              diff = actual ^ pattern;
 372         u8              expected = pattern | gen_inv_idx(counter, is_memset);
 373         const char      *thread_name = current->comm;
 374
 375         if (is_srcbuf)
 376                 pr_warn("%s: srcbuf[0x%x] overwritten! Expected %02x, got %02x\n",
 377                         thread_name, index, expected, actual);
 378         else if ((pattern & PATTERN_COPY)
 379                         && (diff & (PATTERN_COPY | PATTERN_OVERWRITE)))
 380                 pr_warn("%s: dstbuf[0x%x] not copied! Expected %02x, got %02x\n",
 381                         thread_name, index, expected, actual);
 382         else if (diff & PATTERN_SRC)
 383                 pr_warn("%s: dstbuf[0x%x] was copied! Expected %02x, got %02x\n",
 384                         thread_name, index, expected, actual);
 385         else
 386                 pr_warn("%s: dstbuf[0x%x] mismatch! Expected %02x, got %02x\n",
 387                         thread_name, index, expected, actual);
 388 }
 389
 390 static unsigned int dmatest_verify(u8 **bufs, unsigned int start,
 391                 unsigned int end, unsigned int counter, u8 pattern,
 392                 bool is_srcbuf, bool is_memset)
 393 {
 394         unsigned int i;
 395         unsigned int error_count = 0;
 396         u8 actual;
 397         u8 expected;
 398         u8 *buf;
 399         unsigned int counter_orig = counter;
 400
 401         for (; (buf = *bufs); bufs++) {
 402                 counter = counter_orig;
 403                 for (i = start; i < end; i++) {
 404                         actual = buf[i];
 405                         expected = pattern | gen_inv_idx(counter, is_memset);
 406                         if (actual != expected) {
 407                                 if (error_count < MAX_ERROR_COUNT)
 408                                         dmatest_mismatch(actual, pattern, i,
 409                                                          counter, is_srcbuf,
 410                                                          is_memset);
 411                                 error_count++;
 412                         }
 413                         counter++;
 414                 }
 415         }
 416
 417         if (error_count > MAX_ERROR_COUNT)
 418                 pr_warn("%s: %u errors suppressed\n",
 419                         current->comm, error_count - MAX_ERROR_COUNT);
 420
 421         return error_count;
 422 }
 423
 424
 425 static void dmatest_callback(void *arg)
 426 {
 427         struct dmatest_done *done = arg;
 428         struct dmatest_thread *thread =
 429                 container_of(done, struct dmatest_thread, test_done);
 430         if (!thread->done) {
 431                 done->done = true;
 432                 wake_up_all(done->wait);
 433         } else {
 434                 /*
 435                  * If thread->done, it means that this callback occurred
 436                  * after the parent thread has cleaned up. This can
 437                  * happen in the case that driver doesn't implement
 438                  * the terminate_all() functionality and a dma operation
 439                  * did not occur within the timeout period
 440                  */
 441                 WARN(1, "dmatest: Kernel memory may be corrupted!!\n");
 442         }
 443 }
 444
 445 static unsigned int min_odd(unsigned int x, unsigned int y)
 446 {
 447         unsigned int val = min(x, y);
 448
 449         return val % 2 ? val : val - 1;
 450 }
 451
 452 static void result(const char *err, unsigned int n, unsigned int src_off,
 453                    unsigned int dst_off, unsigned int len, unsigned long data)
 454 {
 455         pr_info("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
 456                 current->comm, n, err, src_off, dst_off, len, data);
 457 }
 458
 459 static void dbg_result(const char *err, unsigned int n, unsigned int src_off,
 460                        unsigned int dst_off, unsigned int len,
 461                        unsigned long data)
 462 {
 463         pr_debug("%s: result #%u: '%s' with src_off=0x%x dst_off=0x%x len=0x%x (%lu)\n",
 464                  current->comm, n, err, src_off, dst_off, len, data);
 465 }
 466
 467 #define verbose_result(err, n, src_off, dst_off, len, data) ({  \
 468         if (verbose)                                            \
 469                 result(err, n, src_off, dst_off, len, data);    \
 470         else                                                    \
 471                 dbg_result(err, n, src_off, dst_off, len, data);\
 472 })
 473
 474 static unsigned long long dmatest_persec(s64 runtime, unsigned int val)
 475 {
 476         unsigned long long per_sec = 1000000;
 477
 478         if (runtime <= 0)
 479                 return 0;
 480
 481         /* drop precision until runtime is 32-bits */
 482         while (runtime > UINT_MAX) {
 483                 runtime >>= 1;
 484                 per_sec <<= 1;
 485         }
 486
 487         per_sec *= val;
 488         per_sec = INT_TO_FIXPT(per_sec);
 489         do_div(per_sec, runtime);
 490
 491         return per_sec;
 492 }
 493
 494 static unsigned long long dmatest_KBs(s64 runtime, unsigned long long len)
 495 {
 496         return FIXPT_TO_INT(dmatest_persec(runtime, len >> 10));
 497 }
 498
 499 static void __dmatest_free_test_data(struct dmatest_data *d, unsigned int cnt)
 500 {
 501         unsigned int i;
 502
 503         for (i = 0; i < cnt; i++)
 504                 kfree(d->raw[i]);
 505
 506         kfree(d->aligned);
 507         kfree(d->raw);
 508 }
 509
 510 static void dmatest_free_test_data(struct dmatest_data *d)
 511 {
 512         __dmatest_free_test_data(d, d->cnt);
 513 }
 514
 515 static int dmatest_alloc_test_data(struct dmatest_data *d,
 516                 unsigned int buf_size, u8 align)
 517 {
 518         unsigned int i = 0;
 519
 520         d->raw = kcalloc(d->cnt + 1, sizeof(u8 *), GFP_KERNEL);
 521         if (!d->raw)
 522                 return -ENOMEM;
 523
 524         d->aligned = kcalloc(d->cnt + 1, sizeof(u8 *), GFP_KERNEL);
 525         if (!d->aligned)
 526                 goto err;
 527
 528         for (i = 0; i < d->cnt; i++) {
 529                 d->raw[i] = kmalloc(buf_size + align, GFP_KERNEL);
 530                 if (!d->raw[i])
 531                         goto err;
 532
 533                 /* align to alignment restriction */
 534                 if (align)
 535                         d->aligned[i] = PTR_ALIGN(d->raw[i], align);
 536                 else
 537                         d->aligned[i] = d->raw[i];
 538         }
 539
 540         return 0;
 541 err:
 542         __dmatest_free_test_data(d, i);
 543         return -ENOMEM;
 544 }
 545
 546 /*
 547  * This function repeatedly tests DMA transfers of various lengths and
 548  * offsets for a given operation type until it is told to exit by
 549  * kthread_stop(). There may be multiple threads running this function
 550  * in parallel for a single channel, and there may be multiple channels
 551  * being tested in parallel.
 552  *
 553  * Before each test, the source and destination buffer is initialized
 554  * with a known pattern. This pattern is different depending on
 555  * whether it's in an area which is supposed to be copied or
 556  * overwritten, and different in the source and destination buffers.
 557  * So if the DMA engine doesn't copy exactly what we tell it to copy,
 558  * we'll notice.
 559  */
 560 static int dmatest_func(void *data)
 561 {
 562         struct dmatest_thread   *thread = data;
 563         struct dmatest_done     *done = &thread->test_done;
 564         struct dmatest_info     *info;
 565         struct dmatest_params   *params;
 566         struct dma_chan         *chan;
 567         struct dma_device       *dev;
 568         unsigned int            error_count;
 569         unsigned int            failed_tests = 0;
 570         unsigned int            total_tests = 0;
 571         dma_cookie_t            cookie;
 572         enum dma_status         status;
 573         enum dma_ctrl_flags     flags;
 574         u8                      *pq_coefs = NULL;
 575         int                     ret;
 576         unsigned int            buf_size;
 577         struct dmatest_data     *src;
 578         struct dmatest_data     *dst;
 579         int                     i;
 580         ktime_t                 ktime, start, diff;
 581         ktime_t                 filltime = 0;
 582         ktime_t                 comparetime = 0;
 583         s64                     runtime = 0;
 584         unsigned long long      total_len = 0;
 585         unsigned long long      iops = 0;
 586         u8                      align = 0;
 587         bool                    is_memset = false;
 588         dma_addr_t              *srcs;
 589         dma_addr_t              *dma_pq;
 590
 591         set_freezable();
 592
 593         ret = -ENOMEM;
 594
 595         smp_rmb();
 596         thread->pending = false;
 597         info = thread->info;
 598         params = &info->params;
 599         chan = thread->chan;
 600         dev = chan->device;
 601         src = &thread->src;
 602         dst = &thread->dst;
 603         if (thread->type == DMA_MEMCPY) {
 604                 align = params->alignment < 0 ? dev->copy_align :
 605                                                 params->alignment;
 606                 src->cnt = dst->cnt = 1;
 607         } else if (thread->type == DMA_MEMSET) {
 608                 align = params->alignment < 0 ? dev->fill_align :
 609                                                 params->alignment;
 610                 src->cnt = dst->cnt = 1;
 611                 is_memset = true;
 612         } else if (thread->type == DMA_XOR) {
 613                 /* force odd to ensure dst = src */
 614                 src->cnt = min_odd(params->xor_sources | 1, dev->max_xor);
 615                 dst->cnt = 1;
 616                 align = params->alignment < 0 ? dev->xor_align :
 617                                                 params->alignment;
 618         } else if (thread->type == DMA_PQ) {
 619                 /* force odd to ensure dst = src */
 620                 src->cnt = min_odd(params->pq_sources | 1, dma_maxpq(dev, 0));
 621                 dst->cnt = 2;
 622                 align = params->alignment < 0 ? dev->pq_align :
 623                                                 params->alignment;
 624
 625                 pq_coefs = kmalloc(params->pq_sources + 1, GFP_KERNEL);
 626                 if (!pq_coefs)
 627                         goto err_thread_type;
 628
 629                 for (i = 0; i < src->cnt; i++)
 630                         pq_coefs[i] = 1;
 631         } else
 632                 goto err_thread_type;
 633
 634         /* Check if buffer count fits into map count variable (u8) */
 635         if ((src->cnt + dst->cnt) >= 255) {
 636                 pr_err("too many buffers (%d of 255 supported)\n",
 637                        src->cnt + dst->cnt);
 638                 goto err_free_coefs;
 639         }
 640
 641         buf_size = params->buf_size;
 642         if (1 << align > buf_size) {
 643                 pr_err("%u-byte buffer too small for %d-byte alignment\n",
 644                        buf_size, 1 << align);
 645                 goto err_free_coefs;
 646         }
 647
 648         if (dmatest_alloc_test_data(src, buf_size, align) < 0)
 649                 goto err_free_coefs;
 650
 651         if (dmatest_alloc_test_data(dst, buf_size, align) < 0)
 652                 goto err_src;
 653
 654         set_user_nice(current, 10);
 655
 656         srcs = kcalloc(src->cnt, sizeof(dma_addr_t), GFP_KERNEL);
 657         if (!srcs)
 658                 goto err_dst;
 659
 660         dma_pq = kcalloc(dst->cnt, sizeof(dma_addr_t), GFP_KERNEL);
 661         if (!dma_pq)
 662                 goto err_srcs_array;
 663
 664         /*
 665          * src and dst buffers are freed by ourselves below
 666          */
 667         if (params->polled)
 668                 flags = DMA_CTRL_ACK;
 669         else
 670                 flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
 671
 672         ktime = ktime_get();
 673         while (!(kthread_should_stop() ||
 674                (params->iterations && total_tests >= params->iterations))) {
 675                 struct dma_async_tx_descriptor *tx = NULL;
 676                 struct dmaengine_unmap_data *um;
 677                 dma_addr_t *dsts;
 678                 unsigned int len;
 679
 680                 total_tests++;
 681
 682                 if (params->transfer_size) {
 683                         if (params->transfer_size >= buf_size) {
 684                                 pr_err("%u-byte transfer size must be lower than %u-buffer size\n",
 685                                        params->transfer_size, buf_size);
 686                                 break;
 687                         }
 688                         len = params->transfer_size;
 689                 } else if (params->norandom) {
 690                         len = buf_size;
 691                 } else {
 692                         len = dmatest_random() % buf_size + 1;
 693                 }
 694
 695                 /* Do not alter transfer size explicitly defined by user */
 696                 if (!params->transfer_size) {
 697                         len = (len >> align) << align;
 698                         if (!len)
 699                                 len = 1 << align;
 700                 }
 701                 total_len += len;
 702
 703                 if (params->norandom) {
 704                         src->off = 0;
 705                         dst->off = 0;
 706                 } else {
 707                         src->off = dmatest_random() % (buf_size - len + 1);
 708                         dst->off = dmatest_random() % (buf_size - len + 1);
 709
 710                         src->off = (src->off >> align) << align;
 711                         dst->off = (dst->off >> align) << align;
 712                 }
 713
 714                 if (!params->noverify) {
 715                         start = ktime_get();
 716                         dmatest_init_srcs(src->aligned, src->off, len,
 717                                           buf_size, is_memset);
 718                         dmatest_init_dsts(dst->aligned, dst->off, len,
 719                                           buf_size, is_memset);
 720
 721                         diff = ktime_sub(ktime_get(), start);
 722                         filltime = ktime_add(filltime, diff);
 723                 }
 724
 725                 um = dmaengine_get_unmap_data(dev->dev, src->cnt + dst->cnt,
 726                                               GFP_KERNEL);
 727                 if (!um) {
 728                         failed_tests++;
 729                         result("unmap data NULL", total_tests,
 730                                src->off, dst->off, len, ret);
 731                         continue;
 732                 }
 733
 734                 um->len = buf_size;
 735                 for (i = 0; i < src->cnt; i++) {
 736                         void *buf = src->aligned[i];
 737                         struct page *pg = virt_to_page(buf);
 738                         unsigned long pg_off = offset_in_page(buf);
 739
 740                         um->addr[i] = dma_map_page(dev->dev, pg, pg_off,
 741                                                    um->len, DMA_TO_DEVICE);
 742                         srcs[i] = um->addr[i] + src->off;
 743                         ret = dma_mapping_error(dev->dev, um->addr[i]);
 744                         if (ret) {
 745                                 result("src mapping error", total_tests,
 746                                        src->off, dst->off, len, ret);
 747                                 goto error_unmap_continue;
 748                         }
 749                         um->to_cnt++;
 750                 }
 751                 /* map with DMA_BIDIRECTIONAL to force writeback/invalidate */
 752                 dsts = &um->addr[src->cnt];
 753                 for (i = 0; i < dst->cnt; i++) {
 754                         void *buf = dst->aligned[i];
 755                         struct page *pg = virt_to_page(buf);
 756                         unsigned long pg_off = offset_in_page(buf);
 757
 758                         dsts[i] = dma_map_page(dev->dev, pg, pg_off, um->len,
 759                                                DMA_BIDIRECTIONAL);
 760                         ret = dma_mapping_error(dev->dev, dsts[i]);
 761                         if (ret) {
 762                                 result("dst mapping error", total_tests,
 763                                        src->off, dst->off, len, ret);
 764                                 goto error_unmap_continue;
 765                         }
 766                         um->bidi_cnt++;
 767                 }
 768
 769                 if (thread->type == DMA_MEMCPY)
 770                         tx = dev->device_prep_dma_memcpy(chan,
 771                                                          dsts[0] + dst->off,
 772                                                          srcs[0], len, flags);
 773                 else if (thread->type == DMA_MEMSET)
 774                         tx = dev->device_prep_dma_memset(chan,
 775                                                 dsts[0] + dst->off,
 776                                                 *(src->aligned[0] + src->off),
 777                                                 len, flags);
 778                 else if (thread->type == DMA_XOR)
 779                         tx = dev->device_prep_dma_xor(chan,
 780                                                       dsts[0] + dst->off,
 781                                                       srcs, src->cnt,
 782                                                       len, flags);
 783                 else if (thread->type == DMA_PQ) {
 784                         for (i = 0; i < dst->cnt; i++)
 785                                 dma_pq[i] = dsts[i] + dst->off;
 786                         tx = dev->device_prep_dma_pq(chan, dma_pq, srcs,
 787                                                      src->cnt, pq_coefs,
 788                                                      len, flags);
 789                 }
 790
 791                 if (!tx) {
 792                         result("prep error", total_tests, src->off,
 793                                dst->off, len, ret);
 794                         msleep(100);
 795                         goto error_unmap_continue;
 796                 }
 797
 798                 done->done = false;
 799                 if (!params->polled) {
 800                         tx->callback = dmatest_callback;
 801                         tx->callback_param = done;
 802                 }
 803                 cookie = tx->tx_submit(tx);
 804
 805                 if (dma_submit_error(cookie)) {
 806                         result("submit error", total_tests, src->off,
 807                                dst->off, len, ret);
 808                         msleep(100);
 809                         goto error_unmap_continue;
 810                 }
 811
 812                 if (params->polled) {
 813                         status = dma_sync_wait(chan, cookie);
 814                         dmaengine_terminate_sync(chan);
 815                         if (status == DMA_COMPLETE)
 816                                 done->done = true;
 817                 } else {
 818                         dma_async_issue_pending(chan);
 819
 820                         wait_event_freezable_timeout(thread->done_wait,
 821                                         done->done,
 822                                         msecs_to_jiffies(params->timeout));
 823
 824                         status = dma_async_is_tx_complete(chan, cookie, NULL,
 825                                                           NULL);
 826                 }
 827
 828                 if (!done->done) {
 829                         result("test timed out", total_tests, src->off, dst->off,
 830                                len, 0);
 831                         goto error_unmap_continue;
 832                 } else if (status != DMA_COMPLETE) {
 833                         result(status == DMA_ERROR ?
 834                                "completion error status" :
 835                                "completion busy status", total_tests, src->off,
 836                                dst->off, len, ret);
 837                         goto error_unmap_continue;
 838                 }
 839
 840                 dmaengine_unmap_put(um);
 841
 842                 if (params->noverify) {
 843                         verbose_result("test passed", total_tests, src->off,
 844                                        dst->off, len, 0);
 845                         continue;
 846                 }
 847
 848                 start = ktime_get();
 849                 pr_debug("%s: verifying source buffer...\n", current->comm);
 850                 error_count = dmatest_verify(src->aligned, 0, src->off,
 851                                 0, PATTERN_SRC, true, is_memset);
 852                 error_count += dmatest_verify(src->aligned, src->off,
 853                                 src->off + len, src->off,
 854                                 PATTERN_SRC | PATTERN_COPY, true, is_memset);
 855                 error_count += dmatest_verify(src->aligned, src->off + len,
 856                                 buf_size, src->off + len,
 857                                 PATTERN_SRC, true, is_memset);
 858
 859                 pr_debug("%s: verifying dest buffer...\n", current->comm);
 860                 error_count += dmatest_verify(dst->aligned, 0, dst->off,
 861                                 0, PATTERN_DST, false, is_memset);
 862
 863                 error_count += dmatest_verify(dst->aligned, dst->off,
 864                                 dst->off + len, src->off,
 865                                 PATTERN_SRC | PATTERN_COPY, false, is_memset);
 866
 867                 error_count += dmatest_verify(dst->aligned, dst->off + len,
 868                                 buf_size, dst->off + len,
 869                                 PATTERN_DST, false, is_memset);
 870
 871                 diff = ktime_sub(ktime_get(), start);
 872                 comparetime = ktime_add(comparetime, diff);
 873
 874                 if (error_count) {
 875                         result("data error", total_tests, src->off, dst->off,
 876                                len, error_count);
 877                         failed_tests++;
 878                 } else {
 879                         verbose_result("test passed", total_tests, src->off,
 880                                        dst->off, len, 0);
 881                 }
 882
 883                 continue;
 884
 885 error_unmap_continue:
 886                 dmaengine_unmap_put(um);
 887                 failed_tests++;
 888         }
 889         ktime = ktime_sub(ktime_get(), ktime);
 890         ktime = ktime_sub(ktime, comparetime);
 891         ktime = ktime_sub(ktime, filltime);
 892         runtime = ktime_to_us(ktime);
 893
 894         ret = 0;
 895         kfree(dma_pq);
 896 err_srcs_array:
 897         kfree(srcs);
 898 err_dst:
 899         dmatest_free_test_data(dst);
 900 err_src:
 901         dmatest_free_test_data(src);
 902 err_free_coefs:
 903         kfree(pq_coefs);
 904 err_thread_type:
 905         iops = dmatest_persec(runtime, total_tests);
 906         pr_info("%s: summary %u tests, %u failures %llu.%02llu iops %llu KB/s (%d)\n",
 907                 current->comm, total_tests, failed_tests,
 908                 FIXPT_TO_INT(iops), FIXPT_GET_FRAC(iops),
 909                 dmatest_KBs(runtime, total_len), ret);
 910
 911         /* terminate all transfers on specified channels */
 912         if (ret || failed_tests)
 913                 dmaengine_terminate_sync(chan);
 914
 915         thread->done = true;
 916         wake_up(&thread_wait);
 917
 918         return ret;
 919 }
 920
 921 static void dmatest_cleanup_channel(struct dmatest_chan *dtc)
 922 {
 923         struct dmatest_thread   *thread;
 924         struct dmatest_thread   *_thread;
 925         int                     ret;
 926
 927         list_for_each_entry_safe(thread, _thread, &dtc->threads, node) {
 928                 ret = kthread_stop(thread->task);
 929                 pr_debug("thread %s exited with status %d\n",
 930                          thread->task->comm, ret);
 931                 list_del(&thread->node);
 932                 put_task_struct(thread->task);
 933                 kfree(thread);
 934         }
 935
 936         /* terminate all transfers on specified channels */
 937         dmaengine_terminate_sync(dtc->chan);
 938
 939         kfree(dtc);
 940 }
 941
 942 static int dmatest_add_threads(struct dmatest_info *info,
 943                 struct dmatest_chan *dtc, enum dma_transaction_type type)
 944 {
 945         struct dmatest_params *params = &info->params;
 946         struct dmatest_thread *thread;
 947         struct dma_chan *chan = dtc->chan;
 948         char *op;
 949         unsigned int i;
 950
 951         if (type == DMA_MEMCPY)
 952                 op = "copy";
 953         else if (type == DMA_MEMSET)
 954                 op = "set";
 955         else if (type == DMA_XOR)
 956                 op = "xor";
 957         else if (type == DMA_PQ)
 958                 op = "pq";
 959         else
 960                 return -EINVAL;
 961
 962         for (i = 0; i < params->threads_per_chan; i++) {
 963                 thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL);
 964                 if (!thread) {
 965                         pr_warn("No memory for %s-%s%u\n",
 966                                 dma_chan_name(chan), op, i);
 967                         break;
 968                 }
 969                 thread->info = info;
 970                 thread->chan = dtc->chan;
 971                 thread->type = type;
 972                 thread->test_done.wait = &thread->done_wait;
 973                 init_waitqueue_head(&thread->done_wait);
 974                 smp_wmb();
 975                 thread->task = kthread_create(dmatest_func, thread, "%s-%s%u",
 976                                 dma_chan_name(chan), op, i);
 977                 if (IS_ERR(thread->task)) {
 978                         pr_warn("Failed to create thread %s-%s%u\n",
 979                                 dma_chan_name(chan), op, i);
 980                         kfree(thread);
 981                         break;
 982                 }
 983
 984                 /* srcbuf and dstbuf are allocated by the thread itself */
 985                 get_task_struct(thread->task);
 986                 list_add_tail(&thread->node, &dtc->threads);
 987                 thread->pending = true;
 988         }
 989
 990         return i;
 991 }
 992
 993 static int dmatest_add_channel(struct dmatest_info *info,
 994                 struct dma_chan *chan)
 995 {
 996         struct dmatest_chan     *dtc;
 997         struct dma_device       *dma_dev = chan->device;
 998         unsigned int            thread_count = 0;
 999         int cnt;
1000
1001         dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL);
1002         if (!dtc) {
1003                 pr_warn("No memory for %s\n", dma_chan_name(chan));
1004                 return -ENOMEM;
1005         }
1006
1007         dtc->chan = chan;
1008         INIT_LIST_HEAD(&dtc->threads);
1009
1010         if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) {
1011                 if (dmatest == 0) {
1012                         cnt = dmatest_add_threads(info, dtc, DMA_MEMCPY);
1013                         thread_count += cnt > 0 ? cnt : 0;
1014                 }
1015         }
1016
1017         if (dma_has_cap(DMA_MEMSET, dma_dev->cap_mask)) {
1018                 if (dmatest == 1) {
1019                         cnt = dmatest_add_threads(info, dtc, DMA_MEMSET);
1020                         thread_count += cnt > 0 ? cnt : 0;
1021                 }
1022         }
1023
1024         if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) {
1025                 cnt = dmatest_add_threads(info, dtc, DMA_XOR);
1026                 thread_count += cnt > 0 ? cnt : 0;
1027         }
1028         if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) {
1029                 cnt = dmatest_add_threads(info, dtc, DMA_PQ);
1030                 thread_count += cnt > 0 ? cnt : 0;
1031         }
1032
1033         pr_info("Added %u threads using %s\n",
1034                 thread_count, dma_chan_name(chan));
1035
1036         list_add_tail(&dtc->node, &info->channels);
1037         info->nr_channels++;
1038
1039         return 0;
1040 }
1041
1042 static bool filter(struct dma_chan *chan, void *param)
1043 {
1044         struct dmatest_params *params = param;
1045
1046         if (!dmatest_match_channel(params, chan) ||
1047             !dmatest_match_device(params, chan->device))
1048                 return false;
1049         else
1050                 return true;
1051 }
1052
1053 static void request_channels(struct dmatest_info *info,
1054                              enum dma_transaction_type type)
1055 {
1056         dma_cap_mask_t mask;
1057
1058         dma_cap_zero(mask);
1059         dma_cap_set(type, mask);
1060         for (;;) {
1061                 struct dmatest_params *params = &info->params;
1062                 struct dma_chan *chan;
1063
1064                 chan = dma_request_channel(mask, filter, params);
1065                 if (chan) {
1066                         if (dmatest_add_channel(info, chan)) {
1067                                 dma_release_channel(chan);
1068                                 break; /* add_channel failed, punt */
1069                         }
1070                 } else
1071                         break; /* no more channels available */
1072                 if (params->max_channels &&
1073                     info->nr_channels >= params->max_channels)
1074                         break; /* we have all we need */
1075         }
1076 }
1077
1078 static void add_threaded_test(struct dmatest_info *info)
1079 {
1080         struct dmatest_params *params = &info->params;
1081
1082         /* Copy test parameters */
1083         params->buf_size = test_buf_size;
1084         strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
1085         strlcpy(params->device, strim(test_device), sizeof(params->device));
1086         params->threads_per_chan = threads_per_chan;
1087         params->max_channels = max_channels;
1088         params->iterations = iterations;
1089         params->xor_sources = xor_sources;
1090         params->pq_sources = pq_sources;
1091         params->timeout = timeout;
1092         params->noverify = noverify;
1093         params->norandom = norandom;
1094         params->alignment = alignment;
1095         params->transfer_size = transfer_size;
1096         params->polled = polled;
1097
1098         request_channels(info, DMA_MEMCPY);
1099         request_channels(info, DMA_MEMSET);
1100         request_channels(info, DMA_XOR);
1101         request_channels(info, DMA_PQ);
1102 }
1103
1104 static void run_pending_tests(struct dmatest_info *info)
1105 {
1106         struct dmatest_chan *dtc;
1107         unsigned int thread_count = 0;
1108
1109         list_for_each_entry(dtc, &info->channels, node) {
1110                 struct dmatest_thread *thread;
1111
1112                 thread_count = 0;
1113                 list_for_each_entry(thread, &dtc->threads, node) {
1114                         wake_up_process(thread->task);
1115                         thread_count++;
1116                 }
1117                 pr_info("Started %u threads using %s\n",
1118                         thread_count, dma_chan_name(dtc->chan));
1119         }
1120 }
1121
1122 static void stop_threaded_test(struct dmatest_info *info)
1123 {
1124         struct dmatest_chan *dtc, *_dtc;
1125         struct dma_chan *chan;
1126
1127         list_for_each_entry_safe(dtc, _dtc, &info->channels, node) {
1128                 list_del(&dtc->node);
1129                 chan = dtc->chan;
1130                 dmatest_cleanup_channel(dtc);
1131                 pr_debug("dropped channel %s\n", dma_chan_name(chan));
1132                 dma_release_channel(chan);
1133         }
1134
1135         info->nr_channels = 0;
1136 }
1137
1138 static void start_threaded_tests(struct dmatest_info *info)
1139 {
1140         /* we might be called early to set run=, defer running until all
1141          * parameters have been evaluated
1142          */
1143         if (!info->did_init)
1144                 return;
1145
1146         run_pending_tests(info);
1147 }
1148
1149 static int dmatest_run_get(char *val, const struct kernel_param *kp)
1150 {
1151         struct dmatest_info *info = &test_info;
1152
1153         mutex_lock(&info->lock);
1154         if (is_threaded_test_run(info)) {
1155                 dmatest_run = true;
1156         } else {
1157                 if (!is_threaded_test_pending(info))
1158                         stop_threaded_test(info);
1159                 dmatest_run = false;
1160         }
1161         mutex_unlock(&info->lock);
1162
1163         return param_get_bool(val, kp);
1164 }
1165
1166 static int dmatest_run_set(const char *val, const struct kernel_param *kp)
1167 {
1168         struct dmatest_info *info = &test_info;
1169         int ret;
1170
1171         mutex_lock(&info->lock);
1172         ret = param_set_bool(val, kp);
1173         if (ret) {
1174                 mutex_unlock(&info->lock);
1175                 return ret;
1176         } else if (dmatest_run) {
1177                 if (!is_threaded_test_pending(info)) {
1178                         pr_info("No channels configured, continue with any\n");
1179                         add_threaded_test(info);
1180                 }
1181                 start_threaded_tests(info);
1182         } else {
1183                 stop_threaded_test(info);
1184         }
1185
1186         mutex_unlock(&info->lock);
1187
1188         return ret;
1189 }
1190
1191 static int dmatest_chan_set(const char *val, const struct kernel_param *kp)
1192 {
1193         struct dmatest_info *info = &test_info;
1194         struct dmatest_chan *dtc;
1195         char chan_reset_val[20];
1196         int ret = 0;
1197
1198         mutex_lock(&info->lock);
1199         ret = param_set_copystring(val, kp);
1200         if (ret) {
1201                 mutex_unlock(&info->lock);
1202                 return ret;
1203         }
1204         /*Clear any previously run threads */
1205         if (!is_threaded_test_run(info) && !is_threaded_test_pending(info))
1206                 stop_threaded_test(info);
1207         /* Reject channels that are already registered */
1208         if (is_threaded_test_pending(info)) {
1209                 list_for_each_entry(dtc, &info->channels, node) {
1210                         if (strcmp(dma_chan_name(dtc->chan),
1211                                    strim(test_channel)) == 0) {
1212                                 dtc = list_last_entry(&info->channels,
1213                                                       struct dmatest_chan,
1214                                                       node);
1215                                 strlcpy(chan_reset_val,
1216                                         dma_chan_name(dtc->chan),
1217                                         sizeof(chan_reset_val));
1218                                 ret = -EBUSY;
1219                                 goto add_chan_err;
1220                         }
1221                 }
1222         }
1223
1224         add_threaded_test(info);
1225
1226         /* Check if channel was added successfully */
1227         dtc = list_last_entry(&info->channels, struct dmatest_chan, node);
1228
1229         if (dtc->chan) {
1230                 /*
1231                  * if new channel was not successfully added, revert the
1232                  * "test_channel" string to the name of the last successfully
1233                  * added channel. exception for when users issues empty string
1234                  * to channel parameter.
1235                  */
1236                 if ((strcmp(dma_chan_name(dtc->chan), strim(test_channel)) != 0)
1237                     && (strcmp("", strim(test_channel)) != 0)) {
1238                         ret = -EINVAL;
1239                         strlcpy(chan_reset_val, dma_chan_name(dtc->chan),
1240                                 sizeof(chan_reset_val));
1241                         goto add_chan_err;
1242                 }
1243
1244         } else {
1245                 /* Clear test_channel if no channels were added successfully */
1246                 strlcpy(chan_reset_val, "", sizeof(chan_reset_val));
1247                 ret = -EBUSY;
1248                 goto add_chan_err;
1249         }
1250
1251         mutex_unlock(&info->lock);
1252
1253         return ret;
1254
1255 add_chan_err:
1256         param_set_copystring(chan_reset_val, kp);
1257         mutex_unlock(&info->lock);
1258
1259         return ret;
1260 }
1261
1262 static int dmatest_chan_get(char *val, const struct kernel_param *kp)
1263 {
1264         struct dmatest_info *info = &test_info;
1265
1266         mutex_lock(&info->lock);
1267         if (!is_threaded_test_run(info) && !is_threaded_test_pending(info)) {
1268                 stop_threaded_test(info);
1269                 strlcpy(test_channel, "", sizeof(test_channel));
1270         }
1271         mutex_unlock(&info->lock);
1272
1273         return param_get_string(val, kp);
1274 }
1275
1276 static int dmatest_test_list_get(char *val, const struct kernel_param *kp)
1277 {
1278         struct dmatest_info *info = &test_info;
1279         struct dmatest_chan *dtc;
1280         unsigned int thread_count = 0;
1281
1282         list_for_each_entry(dtc, &info->channels, node) {
1283                 struct dmatest_thread *thread;
1284
1285                 thread_count = 0;
1286                 list_for_each_entry(thread, &dtc->threads, node) {
1287                         thread_count++;
1288                 }
1289                 pr_info("%u threads using %s\n",
1290                         thread_count, dma_chan_name(dtc->chan));
1291         }
1292
1293         return 0;
1294 }
1295
1296 static int __init dmatest_init(void)
1297 {
1298         struct dmatest_info *info = &test_info;
1299         struct dmatest_params *params = &info->params;
1300
1301         if (dmatest_run) {
1302                 mutex_lock(&info->lock);
1303                 add_threaded_test(info);
1304                 run_pending_tests(info);
1305                 mutex_unlock(&info->lock);
1306         }
1307
1308         if (params->iterations && wait)
1309                 wait_event(thread_wait, !is_threaded_test_run(info));
1310
1311         /* module parameters are stable, inittime tests are started,
1312          * let userspace take over 'run' control
1313          */
1314         info->did_init = true;
1315
1316         return 0;
1317 }
1318 /* when compiled-in wait for drivers to load first */
1319 late_initcall(dmatest_init);
1320
1321 static void __exit dmatest_exit(void)
1322 {
1323         struct dmatest_info *info = &test_info;
1324
1325         mutex_lock(&info->lock);
1326         stop_threaded_test(info);
1327         mutex_unlock(&info->lock);
1328 }
1329 module_exit(dmatest_exit);
1330
1331 MODULE_AUTHOR("Haavard Skinnemoen (Atmel)");
1332 MODULE_LICENSE("GPL v2");