1 /* 2 * DMA Engine test module 3 * 4 * Copyright (C) 2007 Atmel Corporation 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 */ 10 #include <linux/delay.h> 11 #include <linux/dmaengine.h> 12 #include <linux/init.h> 13 #include <linux/kthread.h> 14 #include <linux/module.h> 15 #include <linux/moduleparam.h> 16 #include <linux/random.h> 17 #include <linux/wait.h> 18 19 static unsigned int test_buf_size = 16384; 20 module_param(test_buf_size, uint, S_IRUGO); 21 MODULE_PARM_DESC(test_buf_size, "Size of the memcpy test buffer"); 22 23 static char test_channel[20]; 24 module_param_string(channel, test_channel, sizeof(test_channel), S_IRUGO); 25 MODULE_PARM_DESC(channel, "Bus ID of the channel to test (default: any)"); 26 27 static char test_device[20]; 28 module_param_string(device, test_device, sizeof(test_device), S_IRUGO); 29 MODULE_PARM_DESC(device, "Bus ID of the DMA Engine to test (default: any)"); 30 31 static unsigned int threads_per_chan = 1; 32 module_param(threads_per_chan, uint, S_IRUGO); 33 MODULE_PARM_DESC(threads_per_chan, 34 "Number of threads to start per channel (default: 1)"); 35 36 static unsigned int max_channels; 37 module_param(max_channels, uint, S_IRUGO); 38 MODULE_PARM_DESC(max_channels, 39 "Maximum number of channels to use (default: all)"); 40 41 static unsigned int iterations; 42 module_param(iterations, uint, S_IRUGO); 43 MODULE_PARM_DESC(iterations, 44 "Iterations before stopping test (default: infinite)"); 45 46 static unsigned int xor_sources = 3; 47 module_param(xor_sources, uint, S_IRUGO); 48 MODULE_PARM_DESC(xor_sources, 49 "Number of xor source buffers (default: 3)"); 50 51 static unsigned int pq_sources = 3; 52 module_param(pq_sources, uint, S_IRUGO); 53 MODULE_PARM_DESC(pq_sources, 54 "Number of p+q source buffers (default: 3)"); 55 56 /* 57 * Initialization patterns. All bytes in the source buffer has bit 7 58 * set, all bytes in the destination buffer has bit 7 cleared. 59 * 60 * Bit 6 is set for all bytes which are to be copied by the DMA 61 * engine. Bit 5 is set for all bytes which are to be overwritten by 62 * the DMA engine. 63 * 64 * The remaining bits are the inverse of a counter which increments by 65 * one for each byte address. 66 */ 67 #define PATTERN_SRC 0x80 68 #define PATTERN_DST 0x00 69 #define PATTERN_COPY 0x40 70 #define PATTERN_OVERWRITE 0x20 71 #define PATTERN_COUNT_MASK 0x1f 72 73 struct dmatest_thread { 74 struct list_head node; 75 struct task_struct *task; 76 struct dma_chan *chan; 77 u8 **srcs; 78 u8 **dsts; 79 enum dma_transaction_type type; 80 }; 81 82 struct dmatest_chan { 83 struct list_head node; 84 struct dma_chan *chan; 85 struct list_head threads; 86 }; 87 88 /* 89 * These are protected by dma_list_mutex since they're only used by 90 * the DMA filter function callback 91 */ 92 static LIST_HEAD(dmatest_channels); 93 static unsigned int nr_channels; 94 95 static bool dmatest_match_channel(struct dma_chan *chan) 96 { 97 if (test_channel[0] == '\0') 98 return true; 99 return strcmp(dma_chan_name(chan), test_channel) == 0; 100 } 101 102 static bool dmatest_match_device(struct dma_device *device) 103 { 104 if (test_device[0] == '\0') 105 return true; 106 return strcmp(dev_name(device->dev), test_device) == 0; 107 } 108 109 static unsigned long dmatest_random(void) 110 { 111 unsigned long buf; 112 113 get_random_bytes(&buf, sizeof(buf)); 114 return buf; 115 } 116 117 static void dmatest_init_srcs(u8 **bufs, unsigned int start, unsigned int len) 118 { 119 unsigned int i; 120 u8 *buf; 121 122 for (; (buf = *bufs); bufs++) { 123 for (i = 0; i < start; i++) 124 buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK); 125 for ( ; i < start + len; i++) 126 buf[i] = PATTERN_SRC | PATTERN_COPY 127 | (~i & PATTERN_COUNT_MASK); 128 for ( ; i < test_buf_size; i++) 129 buf[i] = PATTERN_SRC | (~i & PATTERN_COUNT_MASK); 130 buf++; 131 } 132 } 133 134 static void dmatest_init_dsts(u8 **bufs, unsigned int start, unsigned int len) 135 { 136 unsigned int i; 137 u8 *buf; 138 139 for (; (buf = *bufs); bufs++) { 140 for (i = 0; i < start; i++) 141 buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK); 142 for ( ; i < start + len; i++) 143 buf[i] = PATTERN_DST | PATTERN_OVERWRITE 144 | (~i & PATTERN_COUNT_MASK); 145 for ( ; i < test_buf_size; i++) 146 buf[i] = PATTERN_DST | (~i & PATTERN_COUNT_MASK); 147 } 148 } 149 150 static void dmatest_mismatch(u8 actual, u8 pattern, unsigned int index, 151 unsigned int counter, bool is_srcbuf) 152 { 153 u8 diff = actual ^ pattern; 154 u8 expected = pattern | (~counter & PATTERN_COUNT_MASK); 155 const char *thread_name = current->comm; 156 157 if (is_srcbuf) 158 pr_warning("%s: srcbuf[0x%x] overwritten!" 159 " Expected %02x, got %02x\n", 160 thread_name, index, expected, actual); 161 else if ((pattern & PATTERN_COPY) 162 && (diff & (PATTERN_COPY | PATTERN_OVERWRITE))) 163 pr_warning("%s: dstbuf[0x%x] not copied!" 164 " Expected %02x, got %02x\n", 165 thread_name, index, expected, actual); 166 else if (diff & PATTERN_SRC) 167 pr_warning("%s: dstbuf[0x%x] was copied!" 168 " Expected %02x, got %02x\n", 169 thread_name, index, expected, actual); 170 else 171 pr_warning("%s: dstbuf[0x%x] mismatch!" 172 " Expected %02x, got %02x\n", 173 thread_name, index, expected, actual); 174 } 175 176 static unsigned int dmatest_verify(u8 **bufs, unsigned int start, 177 unsigned int end, unsigned int counter, u8 pattern, 178 bool is_srcbuf) 179 { 180 unsigned int i; 181 unsigned int error_count = 0; 182 u8 actual; 183 u8 expected; 184 u8 *buf; 185 unsigned int counter_orig = counter; 186 187 for (; (buf = *bufs); bufs++) { 188 counter = counter_orig; 189 for (i = start; i < end; i++) { 190 actual = buf[i]; 191 expected = pattern | (~counter & PATTERN_COUNT_MASK); 192 if (actual != expected) { 193 if (error_count < 32) 194 dmatest_mismatch(actual, pattern, i, 195 counter, is_srcbuf); 196 error_count++; 197 } 198 counter++; 199 } 200 } 201 202 if (error_count > 32) 203 pr_warning("%s: %u errors suppressed\n", 204 current->comm, error_count - 32); 205 206 return error_count; 207 } 208 209 static void dmatest_callback(void *completion) 210 { 211 complete(completion); 212 } 213 214 /* 215 * This function repeatedly tests DMA transfers of various lengths and 216 * offsets for a given operation type until it is told to exit by 217 * kthread_stop(). There may be multiple threads running this function 218 * in parallel for a single channel, and there may be multiple channels 219 * being tested in parallel. 220 * 221 * Before each test, the source and destination buffer is initialized 222 * with a known pattern. This pattern is different depending on 223 * whether it's in an area which is supposed to be copied or 224 * overwritten, and different in the source and destination buffers. 225 * So if the DMA engine doesn't copy exactly what we tell it to copy, 226 * we'll notice. 227 */ 228 static int dmatest_func(void *data) 229 { 230 struct dmatest_thread *thread = data; 231 struct dma_chan *chan; 232 const char *thread_name; 233 unsigned int src_off, dst_off, len; 234 unsigned int error_count; 235 unsigned int failed_tests = 0; 236 unsigned int total_tests = 0; 237 dma_cookie_t cookie; 238 enum dma_status status; 239 enum dma_ctrl_flags flags; 240 u8 pq_coefs[pq_sources]; 241 int ret; 242 int src_cnt; 243 int dst_cnt; 244 int i; 245 246 thread_name = current->comm; 247 248 ret = -ENOMEM; 249 250 smp_rmb(); 251 chan = thread->chan; 252 if (thread->type == DMA_MEMCPY) 253 src_cnt = dst_cnt = 1; 254 else if (thread->type == DMA_XOR) { 255 src_cnt = xor_sources | 1; /* force odd to ensure dst = src */ 256 dst_cnt = 1; 257 } else if (thread->type == DMA_PQ) { 258 src_cnt = pq_sources | 1; /* force odd to ensure dst = src */ 259 dst_cnt = 2; 260 for (i = 0; i < pq_sources; i++) 261 pq_coefs[i] = 1; 262 } else 263 goto err_srcs; 264 265 thread->srcs = kcalloc(src_cnt+1, sizeof(u8 *), GFP_KERNEL); 266 if (!thread->srcs) 267 goto err_srcs; 268 for (i = 0; i < src_cnt; i++) { 269 thread->srcs[i] = kmalloc(test_buf_size, GFP_KERNEL); 270 if (!thread->srcs[i]) 271 goto err_srcbuf; 272 } 273 thread->srcs[i] = NULL; 274 275 thread->dsts = kcalloc(dst_cnt+1, sizeof(u8 *), GFP_KERNEL); 276 if (!thread->dsts) 277 goto err_dsts; 278 for (i = 0; i < dst_cnt; i++) { 279 thread->dsts[i] = kmalloc(test_buf_size, GFP_KERNEL); 280 if (!thread->dsts[i]) 281 goto err_dstbuf; 282 } 283 thread->dsts[i] = NULL; 284 285 set_user_nice(current, 10); 286 287 flags = DMA_CTRL_ACK | DMA_COMPL_SKIP_DEST_UNMAP | DMA_PREP_INTERRUPT; 288 289 while (!kthread_should_stop() 290 && !(iterations && total_tests >= iterations)) { 291 struct dma_device *dev = chan->device; 292 struct dma_async_tx_descriptor *tx = NULL; 293 dma_addr_t dma_srcs[src_cnt]; 294 dma_addr_t dma_dsts[dst_cnt]; 295 struct completion cmp; 296 unsigned long tmo = msecs_to_jiffies(3000); 297 u8 align = 0; 298 299 total_tests++; 300 301 /* honor alignment restrictions */ 302 if (thread->type == DMA_MEMCPY) 303 align = dev->copy_align; 304 else if (thread->type == DMA_XOR) 305 align = dev->xor_align; 306 else if (thread->type == DMA_PQ) 307 align = dev->pq_align; 308 309 if (1 << align > test_buf_size) { 310 pr_err("%u-byte buffer too small for %d-byte alignment\n", 311 test_buf_size, 1 << align); 312 break; 313 } 314 315 len = dmatest_random() % test_buf_size + 1; 316 len = (len >> align) << align; 317 if (!len) 318 len = 1 << align; 319 src_off = dmatest_random() % (test_buf_size - len + 1); 320 dst_off = dmatest_random() % (test_buf_size - len + 1); 321 322 src_off = (src_off >> align) << align; 323 dst_off = (dst_off >> align) << align; 324 325 dmatest_init_srcs(thread->srcs, src_off, len); 326 dmatest_init_dsts(thread->dsts, dst_off, len); 327 328 for (i = 0; i < src_cnt; i++) { 329 u8 *buf = thread->srcs[i] + src_off; 330 331 dma_srcs[i] = dma_map_single(dev->dev, buf, len, 332 DMA_TO_DEVICE); 333 } 334 /* map with DMA_BIDIRECTIONAL to force writeback/invalidate */ 335 for (i = 0; i < dst_cnt; i++) { 336 dma_dsts[i] = dma_map_single(dev->dev, thread->dsts[i], 337 test_buf_size, 338 DMA_BIDIRECTIONAL); 339 } 340 341 342 if (thread->type == DMA_MEMCPY) 343 tx = dev->device_prep_dma_memcpy(chan, 344 dma_dsts[0] + dst_off, 345 dma_srcs[0], len, 346 flags); 347 else if (thread->type == DMA_XOR) 348 tx = dev->device_prep_dma_xor(chan, 349 dma_dsts[0] + dst_off, 350 dma_srcs, xor_sources, 351 len, flags); 352 else if (thread->type == DMA_PQ) { 353 dma_addr_t dma_pq[dst_cnt]; 354 355 for (i = 0; i < dst_cnt; i++) 356 dma_pq[i] = dma_dsts[i] + dst_off; 357 tx = dev->device_prep_dma_pq(chan, dma_pq, dma_srcs, 358 pq_sources, pq_coefs, 359 len, flags); 360 } 361 362 if (!tx) { 363 for (i = 0; i < src_cnt; i++) 364 dma_unmap_single(dev->dev, dma_srcs[i], len, 365 DMA_TO_DEVICE); 366 for (i = 0; i < dst_cnt; i++) 367 dma_unmap_single(dev->dev, dma_dsts[i], 368 test_buf_size, 369 DMA_BIDIRECTIONAL); 370 pr_warning("%s: #%u: prep error with src_off=0x%x " 371 "dst_off=0x%x len=0x%x\n", 372 thread_name, total_tests - 1, 373 src_off, dst_off, len); 374 msleep(100); 375 failed_tests++; 376 continue; 377 } 378 379 init_completion(&cmp); 380 tx->callback = dmatest_callback; 381 tx->callback_param = &cmp; 382 cookie = tx->tx_submit(tx); 383 384 if (dma_submit_error(cookie)) { 385 pr_warning("%s: #%u: submit error %d with src_off=0x%x " 386 "dst_off=0x%x len=0x%x\n", 387 thread_name, total_tests - 1, cookie, 388 src_off, dst_off, len); 389 msleep(100); 390 failed_tests++; 391 continue; 392 } 393 dma_async_issue_pending(chan); 394 395 tmo = wait_for_completion_timeout(&cmp, tmo); 396 status = dma_async_is_tx_complete(chan, cookie, NULL, NULL); 397 398 if (tmo == 0) { 399 pr_warning("%s: #%u: test timed out\n", 400 thread_name, total_tests - 1); 401 failed_tests++; 402 continue; 403 } else if (status != DMA_SUCCESS) { 404 pr_warning("%s: #%u: got completion callback," 405 " but status is \'%s\'\n", 406 thread_name, total_tests - 1, 407 status == DMA_ERROR ? "error" : "in progress"); 408 failed_tests++; 409 continue; 410 } 411 412 /* Unmap by myself (see DMA_COMPL_SKIP_DEST_UNMAP above) */ 413 for (i = 0; i < dst_cnt; i++) 414 dma_unmap_single(dev->dev, dma_dsts[i], test_buf_size, 415 DMA_BIDIRECTIONAL); 416 417 error_count = 0; 418 419 pr_debug("%s: verifying source buffer...\n", thread_name); 420 error_count += dmatest_verify(thread->srcs, 0, src_off, 421 0, PATTERN_SRC, true); 422 error_count += dmatest_verify(thread->srcs, src_off, 423 src_off + len, src_off, 424 PATTERN_SRC | PATTERN_COPY, true); 425 error_count += dmatest_verify(thread->srcs, src_off + len, 426 test_buf_size, src_off + len, 427 PATTERN_SRC, true); 428 429 pr_debug("%s: verifying dest buffer...\n", 430 thread->task->comm); 431 error_count += dmatest_verify(thread->dsts, 0, dst_off, 432 0, PATTERN_DST, false); 433 error_count += dmatest_verify(thread->dsts, dst_off, 434 dst_off + len, src_off, 435 PATTERN_SRC | PATTERN_COPY, false); 436 error_count += dmatest_verify(thread->dsts, dst_off + len, 437 test_buf_size, dst_off + len, 438 PATTERN_DST, false); 439 440 if (error_count) { 441 pr_warning("%s: #%u: %u errors with " 442 "src_off=0x%x dst_off=0x%x len=0x%x\n", 443 thread_name, total_tests - 1, error_count, 444 src_off, dst_off, len); 445 failed_tests++; 446 } else { 447 pr_debug("%s: #%u: No errors with " 448 "src_off=0x%x dst_off=0x%x len=0x%x\n", 449 thread_name, total_tests - 1, 450 src_off, dst_off, len); 451 } 452 } 453 454 ret = 0; 455 for (i = 0; thread->dsts[i]; i++) 456 kfree(thread->dsts[i]); 457 err_dstbuf: 458 kfree(thread->dsts); 459 err_dsts: 460 for (i = 0; thread->srcs[i]; i++) 461 kfree(thread->srcs[i]); 462 err_srcbuf: 463 kfree(thread->srcs); 464 err_srcs: 465 pr_notice("%s: terminating after %u tests, %u failures (status %d)\n", 466 thread_name, total_tests, failed_tests, ret); 467 468 if (iterations > 0) 469 while (!kthread_should_stop()) { 470 DECLARE_WAIT_QUEUE_HEAD(wait_dmatest_exit); 471 interruptible_sleep_on(&wait_dmatest_exit); 472 } 473 474 return ret; 475 } 476 477 static void dmatest_cleanup_channel(struct dmatest_chan *dtc) 478 { 479 struct dmatest_thread *thread; 480 struct dmatest_thread *_thread; 481 int ret; 482 483 list_for_each_entry_safe(thread, _thread, &dtc->threads, node) { 484 ret = kthread_stop(thread->task); 485 pr_debug("dmatest: thread %s exited with status %d\n", 486 thread->task->comm, ret); 487 list_del(&thread->node); 488 kfree(thread); 489 } 490 kfree(dtc); 491 } 492 493 static int dmatest_add_threads(struct dmatest_chan *dtc, enum dma_transaction_type type) 494 { 495 struct dmatest_thread *thread; 496 struct dma_chan *chan = dtc->chan; 497 char *op; 498 unsigned int i; 499 500 if (type == DMA_MEMCPY) 501 op = "copy"; 502 else if (type == DMA_XOR) 503 op = "xor"; 504 else if (type == DMA_PQ) 505 op = "pq"; 506 else 507 return -EINVAL; 508 509 for (i = 0; i < threads_per_chan; i++) { 510 thread = kzalloc(sizeof(struct dmatest_thread), GFP_KERNEL); 511 if (!thread) { 512 pr_warning("dmatest: No memory for %s-%s%u\n", 513 dma_chan_name(chan), op, i); 514 515 break; 516 } 517 thread->chan = dtc->chan; 518 thread->type = type; 519 smp_wmb(); 520 thread->task = kthread_run(dmatest_func, thread, "%s-%s%u", 521 dma_chan_name(chan), op, i); 522 if (IS_ERR(thread->task)) { 523 pr_warning("dmatest: Failed to run thread %s-%s%u\n", 524 dma_chan_name(chan), op, i); 525 kfree(thread); 526 break; 527 } 528 529 /* srcbuf and dstbuf are allocated by the thread itself */ 530 531 list_add_tail(&thread->node, &dtc->threads); 532 } 533 534 return i; 535 } 536 537 static int dmatest_add_channel(struct dma_chan *chan) 538 { 539 struct dmatest_chan *dtc; 540 struct dma_device *dma_dev = chan->device; 541 unsigned int thread_count = 0; 542 unsigned int cnt; 543 544 dtc = kmalloc(sizeof(struct dmatest_chan), GFP_KERNEL); 545 if (!dtc) { 546 pr_warning("dmatest: No memory for %s\n", dma_chan_name(chan)); 547 return -ENOMEM; 548 } 549 550 dtc->chan = chan; 551 INIT_LIST_HEAD(&dtc->threads); 552 553 if (dma_has_cap(DMA_MEMCPY, dma_dev->cap_mask)) { 554 cnt = dmatest_add_threads(dtc, DMA_MEMCPY); 555 thread_count += cnt > 0 ? cnt : 0; 556 } 557 if (dma_has_cap(DMA_XOR, dma_dev->cap_mask)) { 558 cnt = dmatest_add_threads(dtc, DMA_XOR); 559 thread_count += cnt > 0 ? cnt : 0; 560 } 561 if (dma_has_cap(DMA_PQ, dma_dev->cap_mask)) { 562 cnt = dmatest_add_threads(dtc, DMA_PQ); 563 thread_count += cnt > 0 ?: 0; 564 } 565 566 pr_info("dmatest: Started %u threads using %s\n", 567 thread_count, dma_chan_name(chan)); 568 569 list_add_tail(&dtc->node, &dmatest_channels); 570 nr_channels++; 571 572 return 0; 573 } 574 575 static bool filter(struct dma_chan *chan, void *param) 576 { 577 if (!dmatest_match_channel(chan) || !dmatest_match_device(chan->device)) 578 return false; 579 else 580 return true; 581 } 582 583 static int __init dmatest_init(void) 584 { 585 dma_cap_mask_t mask; 586 struct dma_chan *chan; 587 int err = 0; 588 589 dma_cap_zero(mask); 590 dma_cap_set(DMA_MEMCPY, mask); 591 for (;;) { 592 chan = dma_request_channel(mask, filter, NULL); 593 if (chan) { 594 err = dmatest_add_channel(chan); 595 if (err) { 596 dma_release_channel(chan); 597 break; /* add_channel failed, punt */ 598 } 599 } else 600 break; /* no more channels available */ 601 if (max_channels && nr_channels >= max_channels) 602 break; /* we have all we need */ 603 } 604 605 return err; 606 } 607 /* when compiled-in wait for drivers to load first */ 608 late_initcall(dmatest_init); 609 610 static void __exit dmatest_exit(void) 611 { 612 struct dmatest_chan *dtc, *_dtc; 613 struct dma_chan *chan; 614 615 list_for_each_entry_safe(dtc, _dtc, &dmatest_channels, node) { 616 list_del(&dtc->node); 617 chan = dtc->chan; 618 dmatest_cleanup_channel(dtc); 619 pr_debug("dmatest: dropped channel %s\n", 620 dma_chan_name(chan)); 621 dma_release_channel(chan); 622 } 623 } 624 module_exit(dmatest_exit); 625 626 MODULE_AUTHOR("Haavard Skinnemoen <hskinnemoen@atmel.com>"); 627 MODULE_LICENSE("GPL v2"); 628