drivers/firmware/tegra/bpmp-debugfs.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (c) 2017, NVIDIA CORPORATION.  All rights reserved.
   4  */
   5 #include <linux/debugfs.h>
   6 #include <linux/dma-mapping.h>
   7 #include <linux/slab.h>
   8 #include <linux/uaccess.h>
   9
  10 #include <soc/tegra/bpmp.h>
  11 #include <soc/tegra/bpmp-abi.h>
  12
  13 static DEFINE_MUTEX(bpmp_debug_lock);
  14
  15 struct seqbuf {
  16         char *buf;
  17         size_t pos;
  18         size_t size;
  19 };
  20
  21 static void seqbuf_init(struct seqbuf *seqbuf, void *buf, size_t size)
  22 {
  23         seqbuf->buf = buf;
  24         seqbuf->size = size;
  25         seqbuf->pos = 0;
  26 }
  27
  28 static size_t seqbuf_avail(struct seqbuf *seqbuf)
  29 {
  30         return seqbuf->pos < seqbuf->size ? seqbuf->size - seqbuf->pos : 0;
  31 }
  32
  33 static size_t seqbuf_status(struct seqbuf *seqbuf)
  34 {
  35         return seqbuf->pos <= seqbuf->size ? 0 : -EOVERFLOW;
  36 }
  37
  38 static int seqbuf_eof(struct seqbuf *seqbuf)
  39 {
  40         return seqbuf->pos >= seqbuf->size;
  41 }
  42
  43 static int seqbuf_read(struct seqbuf *seqbuf, void *buf, size_t nbyte)
  44 {
  45         nbyte = min(nbyte, seqbuf_avail(seqbuf));
  46         memcpy(buf, seqbuf->buf + seqbuf->pos, nbyte);
  47         seqbuf->pos += nbyte;
  48         return seqbuf_status(seqbuf);
  49 }
  50
  51 static int seqbuf_read_u32(struct seqbuf *seqbuf, uint32_t *v)
  52 {
  53         int err;
  54
  55         err = seqbuf_read(seqbuf, v, 4);
  56         *v = le32_to_cpu(*v);
  57         return err;
  58 }
  59
  60 static int seqbuf_read_str(struct seqbuf *seqbuf, const char **str)
  61 {
  62         *str = seqbuf->buf + seqbuf->pos;
  63         seqbuf->pos += strnlen(*str, seqbuf_avail(seqbuf));
  64         seqbuf->pos++;
  65         return seqbuf_status(seqbuf);
  66 }
  67
  68 static void seqbuf_seek(struct seqbuf *seqbuf, ssize_t offset)
  69 {
  70         seqbuf->pos += offset;
  71 }
  72
  73 /* map filename in Linux debugfs to corresponding entry in BPMP */
  74 static const char *get_filename(struct tegra_bpmp *bpmp,
  75                                 const struct file *file, char *buf, int size)
  76 {
  77         char root_path_buf[512];
  78         const char *root_path;
  79         const char *filename;
  80         size_t root_len;
  81
  82         root_path = dentry_path(bpmp->debugfs_mirror, root_path_buf,
  83                                 sizeof(root_path_buf));
  84         if (IS_ERR(root_path))
  85                 return NULL;
  86
  87         root_len = strlen(root_path);
  88
  89         filename = dentry_path(file->f_path.dentry, buf, size);
  90         if (IS_ERR(filename))
  91                 return NULL;
  92
  93         if (strlen(filename) < root_len ||
  94                         strncmp(filename, root_path, root_len))
  95                 return NULL;
  96
  97         filename += root_len;
  98
  99         return filename;
 100 }
 101
 102 static int mrq_debug_open(struct tegra_bpmp *bpmp, const char *name,
 103                           uint32_t *fd, uint32_t *len, bool write)
 104 {
 105         struct mrq_debug_request req = {
 106                 .cmd = cpu_to_le32(write ? CMD_DEBUG_OPEN_WO : CMD_DEBUG_OPEN_RO),
 107         };
 108         struct mrq_debug_response resp;
 109         struct tegra_bpmp_message msg = {
 110                 .mrq = MRQ_DEBUG,
 111                 .tx = {
 112                         .data = &req,
 113                         .size = sizeof(req),
 114                 },
 115                 .rx = {
 116                         .data = &resp,
 117                         .size = sizeof(resp),
 118                 },
 119         };
 120         ssize_t sz_name;
 121         int err = 0;
 122
 123         sz_name = strscpy(req.fop.name, name, sizeof(req.fop.name));
 124         if (sz_name < 0) {
 125                 pr_err("File name too large: %s\n", name);
 126                 return -EINVAL;
 127         }
 128
 129         err = tegra_bpmp_transfer(bpmp, &msg);
 130         if (err < 0)
 131                 return err;
 132         else if (msg.rx.ret < 0)
 133                 return -EINVAL;
 134
 135         *len = resp.fop.datalen;
 136         *fd = resp.fop.fd;
 137
 138         return 0;
 139 }
 140
 141 static int mrq_debug_close(struct tegra_bpmp *bpmp, uint32_t fd)
 142 {
 143         struct mrq_debug_request req = {
 144                 .cmd = cpu_to_le32(CMD_DEBUG_CLOSE),
 145                 .frd = {
 146                         .fd = fd,
 147                 },
 148         };
 149         struct mrq_debug_response resp;
 150         struct tegra_bpmp_message msg = {
 151                 .mrq = MRQ_DEBUG,
 152                 .tx = {
 153                         .data = &req,
 154                         .size = sizeof(req),
 155                 },
 156                 .rx = {
 157                         .data = &resp,
 158                         .size = sizeof(resp),
 159                 },
 160         };
 161         int err = 0;
 162
 163         err = tegra_bpmp_transfer(bpmp, &msg);
 164         if (err < 0)
 165                 return err;
 166         else if (msg.rx.ret < 0)
 167                 return -EINVAL;
 168
 169         return 0;
 170 }
 171
 172 static int mrq_debug_read(struct tegra_bpmp *bpmp, const char *name,
 173                           char *data, size_t sz_data, uint32_t *nbytes)
 174 {
 175         struct mrq_debug_request req = {
 176                 .cmd = cpu_to_le32(CMD_DEBUG_READ),
 177         };
 178         struct mrq_debug_response resp;
 179         struct tegra_bpmp_message msg = {
 180                 .mrq = MRQ_DEBUG,
 181                 .tx = {
 182                         .data = &req,
 183                         .size = sizeof(req),
 184                 },
 185                 .rx = {
 186                         .data = &resp,
 187                         .size = sizeof(resp),
 188                 },
 189         };
 190         uint32_t fd = 0, len = 0;
 191         int remaining, err;
 192
 193         mutex_lock(&bpmp_debug_lock);
 194         err = mrq_debug_open(bpmp, name, &fd, &len, 0);
 195         if (err)
 196                 goto out;
 197
 198         if (len > sz_data) {
 199                 err = -EFBIG;
 200                 goto close;
 201         }
 202
 203         req.frd.fd = fd;
 204         remaining = len;
 205
 206         while (remaining > 0) {
 207                 err = tegra_bpmp_transfer(bpmp, &msg);
 208                 if (err < 0) {
 209                         goto close;
 210                 } else if (msg.rx.ret < 0) {
 211                         err = -EINVAL;
 212                         goto close;
 213                 }
 214
 215                 if (resp.frd.readlen > remaining) {
 216                         pr_err("%s: read data length invalid\n", __func__);
 217                         err = -EINVAL;
 218                         goto close;
 219                 }
 220
 221                 memcpy(data, resp.frd.data, resp.frd.readlen);
 222                 data += resp.frd.readlen;
 223                 remaining -= resp.frd.readlen;
 224         }
 225
 226         *nbytes = len;
 227
 228 close:
 229         err = mrq_debug_close(bpmp, fd);
 230 out:
 231         mutex_unlock(&bpmp_debug_lock);
 232         return err;
 233 }
 234
 235 static int mrq_debug_write(struct tegra_bpmp *bpmp, const char *name,
 236                            uint8_t *data, size_t sz_data)
 237 {
 238         struct mrq_debug_request req = {
 239                 .cmd = cpu_to_le32(CMD_DEBUG_WRITE)
 240         };
 241         struct mrq_debug_response resp;
 242         struct tegra_bpmp_message msg = {
 243                 .mrq = MRQ_DEBUG,
 244                 .tx = {
 245                         .data = &req,
 246                         .size = sizeof(req),
 247                 },
 248                 .rx = {
 249                         .data = &resp,
 250                         .size = sizeof(resp),
 251                 },
 252         };
 253         uint32_t fd = 0, len = 0;
 254         size_t remaining;
 255         int err;
 256
 257         mutex_lock(&bpmp_debug_lock);
 258         err = mrq_debug_open(bpmp, name, &fd, &len, 1);
 259         if (err)
 260                 goto out;
 261
 262         if (sz_data > len) {
 263                 err = -EINVAL;
 264                 goto close;
 265         }
 266
 267         req.fwr.fd = fd;
 268         remaining = sz_data;
 269
 270         while (remaining > 0) {
 271                 len = min(remaining, sizeof(req.fwr.data));
 272                 memcpy(req.fwr.data, data, len);
 273                 req.fwr.datalen = len;
 274
 275                 err = tegra_bpmp_transfer(bpmp, &msg);
 276                 if (err < 0) {
 277                         goto close;
 278                 } else if (msg.rx.ret < 0) {
 279                         err = -EINVAL;
 280                         goto close;
 281                 }
 282
 283                 data += req.fwr.datalen;
 284                 remaining -= req.fwr.datalen;
 285         }
 286
 287 close:
 288         err = mrq_debug_close(bpmp, fd);
 289 out:
 290         mutex_unlock(&bpmp_debug_lock);
 291         return err;
 292 }
 293
 294 static int bpmp_debug_show(struct seq_file *m, void *p)
 295 {
 296         struct file *file = m->private;
 297         struct inode *inode = file_inode(file);
 298         struct tegra_bpmp *bpmp = inode->i_private;
 299         char *databuf = NULL;
 300         char fnamebuf[256];
 301         const char *filename;
 302         uint32_t nbytes = 0;
 303         size_t len;
 304         int err;
 305
 306         len = seq_get_buf(m, &databuf);
 307         if (!databuf)
 308                 return -ENOMEM;
 309
 310         filename = get_filename(bpmp, file, fnamebuf, sizeof(fnamebuf));
 311         if (!filename)
 312                 return -ENOENT;
 313
 314         err = mrq_debug_read(bpmp, filename, databuf, len, &nbytes);
 315         if (!err)
 316                 seq_commit(m, nbytes);
 317
 318         return err;
 319 }
 320
 321 static ssize_t bpmp_debug_store(struct file *file, const char __user *buf,
 322                 size_t count, loff_t *f_pos)
 323 {
 324         struct inode *inode = file_inode(file);
 325         struct tegra_bpmp *bpmp = inode->i_private;
 326         char *databuf = NULL;
 327         char fnamebuf[256];
 328         const char *filename;
 329         ssize_t err;
 330
 331         filename = get_filename(bpmp, file, fnamebuf, sizeof(fnamebuf));
 332         if (!filename)
 333                 return -ENOENT;
 334
 335         databuf = kmalloc(count, GFP_KERNEL);
 336         if (!databuf)
 337                 return -ENOMEM;
 338
 339         if (copy_from_user(databuf, buf, count)) {
 340                 err = -EFAULT;
 341                 goto free_ret;
 342         }
 343
 344         err = mrq_debug_write(bpmp, filename, databuf, count);
 345
 346 free_ret:
 347         kfree(databuf);
 348
 349         return err ?: count;
 350 }
 351
 352 static int bpmp_debug_open(struct inode *inode, struct file *file)
 353 {
 354         return single_open_size(file, bpmp_debug_show, file, SZ_256K);
 355 }
 356
 357 static const struct file_operations bpmp_debug_fops = {
 358         .open           = bpmp_debug_open,
 359         .read           = seq_read,
 360         .llseek         = seq_lseek,
 361         .write          = bpmp_debug_store,
 362         .release        = single_release,
 363 };
 364
 365 static int bpmp_populate_debugfs_inband(struct tegra_bpmp *bpmp,
 366                                         struct dentry *parent,
 367                                         char *ppath)
 368 {
 369         const size_t pathlen = SZ_256;
 370         const size_t bufsize = SZ_16K;
 371         uint32_t dsize, attrs = 0;
 372         struct dentry *dentry;
 373         struct seqbuf seqbuf;
 374         char *buf, *pathbuf;
 375         const char *name;
 376         int err = 0;
 377
 378         if (!bpmp || !parent || !ppath)
 379                 return -EINVAL;
 380
 381         buf = kmalloc(bufsize, GFP_KERNEL);
 382         if (!buf)
 383                 return -ENOMEM;
 384
 385         pathbuf = kzalloc(pathlen, GFP_KERNEL);
 386         if (!pathbuf) {
 387                 kfree(buf);
 388                 return -ENOMEM;
 389         }
 390
 391         err = mrq_debug_read(bpmp, ppath, buf, bufsize, &dsize);
 392         if (err)
 393                 goto out;
 394
 395         seqbuf_init(&seqbuf, buf, dsize);
 396
 397         while (!seqbuf_eof(&seqbuf)) {
 398                 err = seqbuf_read_u32(&seqbuf, &attrs);
 399                 if (err)
 400                         goto out;
 401
 402                 err = seqbuf_read_str(&seqbuf, &name);
 403                 if (err < 0)
 404                         goto out;
 405
 406                 if (attrs & DEBUGFS_S_ISDIR) {
 407                         size_t len;
 408
 409                         dentry = debugfs_create_dir(name, parent);
 410                         if (IS_ERR(dentry)) {
 411                                 err = PTR_ERR(dentry);
 412                                 goto out;
 413                         }
 414
 415                         len = snprintf(pathbuf, pathlen, "%s%s/", ppath, name);
 416                         if (len >= pathlen) {
 417                                 err = -EINVAL;
 418                                 goto out;
 419                         }
 420
 421                         err = bpmp_populate_debugfs_inband(bpmp, dentry,
 422                                                            pathbuf);
 423                         if (err < 0)
 424                                 goto out;
 425                 } else {
 426                         umode_t mode;
 427
 428                         mode = attrs & DEBUGFS_S_IRUSR ? 0400 : 0;
 429                         mode |= attrs & DEBUGFS_S_IWUSR ? 0200 : 0;
 430                         dentry = debugfs_create_file(name, mode, parent, bpmp,
 431                                                      &bpmp_debug_fops);
 432                         if (!dentry) {
 433                                 err = -ENOMEM;
 434                                 goto out;
 435                         }
 436                 }
 437         }
 438
 439 out:
 440         kfree(pathbuf);
 441         kfree(buf);
 442
 443         return err;
 444 }
 445
 446 static int mrq_debugfs_read(struct tegra_bpmp *bpmp,
 447                             dma_addr_t name, size_t sz_name,
 448                             dma_addr_t data, size_t sz_data,
 449                             size_t *nbytes)
 450 {
 451         struct mrq_debugfs_request req = {
 452                 .cmd = cpu_to_le32(CMD_DEBUGFS_READ),
 453                 .fop = {
 454                         .fnameaddr = cpu_to_le32((uint32_t)name),
 455                         .fnamelen = cpu_to_le32((uint32_t)sz_name),
 456                         .dataaddr = cpu_to_le32((uint32_t)data),
 457                         .datalen = cpu_to_le32((uint32_t)sz_data),
 458                 },
 459         };
 460         struct mrq_debugfs_response resp;
 461         struct tegra_bpmp_message msg = {
 462                 .mrq = MRQ_DEBUGFS,
 463                 .tx = {
 464                         .data = &req,
 465                         .size = sizeof(req),
 466                 },
 467                 .rx = {
 468                         .data = &resp,
 469                         .size = sizeof(resp),
 470                 },
 471         };
 472         int err;
 473
 474         err = tegra_bpmp_transfer(bpmp, &msg);
 475         if (err < 0)
 476                 return err;
 477         else if (msg.rx.ret < 0)
 478                 return -EINVAL;
 479
 480         *nbytes = (size_t)resp.fop.nbytes;
 481
 482         return 0;
 483 }
 484
 485 static int mrq_debugfs_write(struct tegra_bpmp *bpmp,
 486                              dma_addr_t name, size_t sz_name,
 487                              dma_addr_t data, size_t sz_data)
 488 {
 489         const struct mrq_debugfs_request req = {
 490                 .cmd = cpu_to_le32(CMD_DEBUGFS_WRITE),
 491                 .fop = {
 492                         .fnameaddr = cpu_to_le32((uint32_t)name),
 493                         .fnamelen = cpu_to_le32((uint32_t)sz_name),
 494                         .dataaddr = cpu_to_le32((uint32_t)data),
 495                         .datalen = cpu_to_le32((uint32_t)sz_data),
 496                 },
 497         };
 498         struct tegra_bpmp_message msg = {
 499                 .mrq = MRQ_DEBUGFS,
 500                 .tx = {
 501                         .data = &req,
 502                         .size = sizeof(req),
 503                 },
 504         };
 505
 506         return tegra_bpmp_transfer(bpmp, &msg);
 507 }
 508
 509 static int mrq_debugfs_dumpdir(struct tegra_bpmp *bpmp, dma_addr_t addr,
 510                                size_t size, size_t *nbytes)
 511 {
 512         const struct mrq_debugfs_request req = {
 513                 .cmd = cpu_to_le32(CMD_DEBUGFS_DUMPDIR),
 514                 .dumpdir = {
 515                         .dataaddr = cpu_to_le32((uint32_t)addr),
 516                         .datalen = cpu_to_le32((uint32_t)size),
 517                 },
 518         };
 519         struct mrq_debugfs_response resp;
 520         struct tegra_bpmp_message msg = {
 521                 .mrq = MRQ_DEBUGFS,
 522                 .tx = {
 523                         .data = &req,
 524                         .size = sizeof(req),
 525                 },
 526                 .rx = {
 527                         .data = &resp,
 528                         .size = sizeof(resp),
 529                 },
 530         };
 531         int err;
 532
 533         err = tegra_bpmp_transfer(bpmp, &msg);
 534         if (err < 0)
 535                 return err;
 536         else if (msg.rx.ret < 0)
 537                 return -EINVAL;
 538
 539         *nbytes = (size_t)resp.dumpdir.nbytes;
 540
 541         return 0;
 542 }
 543
 544 static int debugfs_show(struct seq_file *m, void *p)
 545 {
 546         struct file *file = m->private;
 547         struct inode *inode = file_inode(file);
 548         struct tegra_bpmp *bpmp = inode->i_private;
 549         const size_t datasize = m->size;
 550         const size_t namesize = SZ_256;
 551         void *datavirt, *namevirt;
 552         dma_addr_t dataphys, namephys;
 553         char buf[256];
 554         const char *filename;
 555         size_t len, nbytes;
 556         int err;
 557
 558         filename = get_filename(bpmp, file, buf, sizeof(buf));
 559         if (!filename)
 560                 return -ENOENT;
 561
 562         namevirt = dma_alloc_coherent(bpmp->dev, namesize, &namephys,
 563                                       GFP_KERNEL | GFP_DMA32);
 564         if (!namevirt)
 565                 return -ENOMEM;
 566
 567         datavirt = dma_alloc_coherent(bpmp->dev, datasize, &dataphys,
 568                                       GFP_KERNEL | GFP_DMA32);
 569         if (!datavirt) {
 570                 err = -ENOMEM;
 571                 goto free_namebuf;
 572         }
 573
 574         len = strlen(filename);
 575         strncpy(namevirt, filename, namesize);
 576
 577         err = mrq_debugfs_read(bpmp, namephys, len, dataphys, datasize,
 578                                &nbytes);
 579
 580         if (!err)
 581                 seq_write(m, datavirt, nbytes);
 582
 583         dma_free_coherent(bpmp->dev, datasize, datavirt, dataphys);
 584 free_namebuf:
 585         dma_free_coherent(bpmp->dev, namesize, namevirt, namephys);
 586
 587         return err;
 588 }
 589
 590 static int debugfs_open(struct inode *inode, struct file *file)
 591 {
 592         return single_open_size(file, debugfs_show, file, SZ_128K);
 593 }
 594
 595 static ssize_t debugfs_store(struct file *file, const char __user *buf,
 596                 size_t count, loff_t *f_pos)
 597 {
 598         struct inode *inode = file_inode(file);
 599         struct tegra_bpmp *bpmp = inode->i_private;
 600         const size_t datasize = count;
 601         const size_t namesize = SZ_256;
 602         void *datavirt, *namevirt;
 603         dma_addr_t dataphys, namephys;
 604         char fnamebuf[256];
 605         const char *filename;
 606         size_t len;
 607         int err;
 608
 609         filename = get_filename(bpmp, file, fnamebuf, sizeof(fnamebuf));
 610         if (!filename)
 611                 return -ENOENT;
 612
 613         namevirt = dma_alloc_coherent(bpmp->dev, namesize, &namephys,
 614                                       GFP_KERNEL | GFP_DMA32);
 615         if (!namevirt)
 616                 return -ENOMEM;
 617
 618         datavirt = dma_alloc_coherent(bpmp->dev, datasize, &dataphys,
 619                                       GFP_KERNEL | GFP_DMA32);
 620         if (!datavirt) {
 621                 err = -ENOMEM;
 622                 goto free_namebuf;
 623         }
 624
 625         len = strlen(filename);
 626         strncpy(namevirt, filename, namesize);
 627
 628         if (copy_from_user(datavirt, buf, count)) {
 629                 err = -EFAULT;
 630                 goto free_databuf;
 631         }
 632
 633         err = mrq_debugfs_write(bpmp, namephys, len, dataphys,
 634                                 count);
 635
 636 free_databuf:
 637         dma_free_coherent(bpmp->dev, datasize, datavirt, dataphys);
 638 free_namebuf:
 639         dma_free_coherent(bpmp->dev, namesize, namevirt, namephys);
 640
 641         return err ?: count;
 642 }
 643
 644 static const struct file_operations debugfs_fops = {
 645         .open           = debugfs_open,
 646         .read           = seq_read,
 647         .llseek         = seq_lseek,
 648         .write          = debugfs_store,
 649         .release        = single_release,
 650 };
 651
 652 static int bpmp_populate_dir(struct tegra_bpmp *bpmp, struct seqbuf *seqbuf,
 653                              struct dentry *parent, uint32_t depth)
 654 {
 655         int err;
 656         uint32_t d, t;
 657         const char *name;
 658         struct dentry *dentry;
 659
 660         while (!seqbuf_eof(seqbuf)) {
 661                 err = seqbuf_read_u32(seqbuf, &d);
 662                 if (err < 0)
 663                         return err;
 664
 665                 if (d < depth) {
 666                         seqbuf_seek(seqbuf, -4);
 667                         /* go up a level */
 668                         return 0;
 669                 } else if (d != depth) {
 670                         /* malformed data received from BPMP */
 671                         return -EIO;
 672                 }
 673
 674                 err = seqbuf_read_u32(seqbuf, &t);
 675                 if (err < 0)
 676                         return err;
 677                 err = seqbuf_read_str(seqbuf, &name);
 678                 if (err < 0)
 679                         return err;
 680
 681                 if (t & DEBUGFS_S_ISDIR) {
 682                         dentry = debugfs_create_dir(name, parent);
 683                         if (!dentry)
 684                                 return -ENOMEM;
 685                         err = bpmp_populate_dir(bpmp, seqbuf, dentry, depth+1);
 686                         if (err < 0)
 687                                 return err;
 688                 } else {
 689                         umode_t mode;
 690
 691                         mode = t & DEBUGFS_S_IRUSR ? S_IRUSR : 0;
 692                         mode |= t & DEBUGFS_S_IWUSR ? S_IWUSR : 0;
 693                         dentry = debugfs_create_file(name, mode,
 694                                                      parent, bpmp,
 695                                                      &debugfs_fops);
 696                         if (!dentry)
 697                                 return -ENOMEM;
 698                 }
 699         }
 700
 701         return 0;
 702 }
 703
 704 static int bpmp_populate_debugfs_shmem(struct tegra_bpmp *bpmp)
 705 {
 706         struct seqbuf seqbuf;
 707         const size_t sz = SZ_512K;
 708         dma_addr_t phys;
 709         size_t nbytes;
 710         void *virt;
 711         int err;
 712
 713         virt = dma_alloc_coherent(bpmp->dev, sz, &phys,
 714                                   GFP_KERNEL | GFP_DMA32);
 715         if (!virt)
 716                 return -ENOMEM;
 717
 718         err = mrq_debugfs_dumpdir(bpmp, phys, sz, &nbytes);
 719         if (err < 0) {
 720                 goto free;
 721         } else if (nbytes > sz) {
 722                 err = -EINVAL;
 723                 goto free;
 724         }
 725
 726         seqbuf_init(&seqbuf, virt, nbytes);
 727         err = bpmp_populate_dir(bpmp, &seqbuf, bpmp->debugfs_mirror, 0);
 728 free:
 729         dma_free_coherent(bpmp->dev, sz, virt, phys);
 730
 731         return err;
 732 }
 733
 734 int tegra_bpmp_init_debugfs(struct tegra_bpmp *bpmp)
 735 {
 736         struct dentry *root;
 737         bool inband;
 738         int err;
 739
 740         inband = tegra_bpmp_mrq_is_supported(bpmp, MRQ_DEBUG);
 741
 742         if (!inband && !tegra_bpmp_mrq_is_supported(bpmp, MRQ_DEBUGFS))
 743                 return 0;
 744
 745         root = debugfs_create_dir("bpmp", NULL);
 746         if (!root)
 747                 return -ENOMEM;
 748
 749         bpmp->debugfs_mirror = debugfs_create_dir("debug", root);
 750         if (!bpmp->debugfs_mirror) {
 751                 err = -ENOMEM;
 752                 goto out;
 753         }
 754
 755         if (inband)
 756                 err = bpmp_populate_debugfs_inband(bpmp, bpmp->debugfs_mirror,
 757                                                    "/");
 758         else
 759                 err = bpmp_populate_debugfs_shmem(bpmp);
 760
 761 out:
 762         if (err < 0)
 763                 debugfs_remove_recursive(root);
 764
 765         return err;
 766 }