drivers/char/tpm/tpm_tis_core.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2005, 2006 IBM Corporation
   4  * Copyright (C) 2014, 2015 Intel Corporation
   5  *
   6  * Authors:
   7  * Leendert van Doorn <leendert@watson.ibm.com>
   8  * Kylene Hall <kjhall@us.ibm.com>
   9  *
  10  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  11  *
  12  * Device driver for TCG/TCPA TPM (trusted platform module).
  13  * Specifications at www.trustedcomputinggroup.org
  14  *
  15  * This device driver implements the TPM interface as defined in
  16  * the TCG TPM Interface Spec version 1.2, revision 1.0.
  17  */
  18 #include <linux/init.h>
  19 #include <linux/module.h>
  20 #include <linux/moduleparam.h>
  21 #include <linux/pnp.h>
  22 #include <linux/slab.h>
  23 #include <linux/interrupt.h>
  24 #include <linux/wait.h>
  25 #include <linux/acpi.h>
  26 #include <linux/freezer.h>
  27 #include "tpm.h"
  28 #include "tpm_tis_core.h"
  29
  30 static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value);
  31
  32 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
  33                                         bool check_cancel, bool *canceled)
  34 {
  35         u8 status = chip->ops->status(chip);
  36
  37         *canceled = false;
  38         if ((status & mask) == mask)
  39                 return true;
  40         if (check_cancel && chip->ops->req_canceled(chip, status)) {
  41                 *canceled = true;
  42                 return true;
  43         }
  44         return false;
  45 }
  46
  47 static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
  48                 unsigned long timeout, wait_queue_head_t *queue,
  49                 bool check_cancel)
  50 {
  51         unsigned long stop;
  52         long rc;
  53         u8 status;
  54         bool canceled = false;
  55
  56         /* check current status */
  57         status = chip->ops->status(chip);
  58         if ((status & mask) == mask)
  59                 return 0;
  60
  61         stop = jiffies + timeout;
  62
  63         if (chip->flags & TPM_CHIP_FLAG_IRQ) {
  64 again:
  65                 timeout = stop - jiffies;
  66                 if ((long)timeout <= 0)
  67                         return -ETIME;
  68                 rc = wait_event_interruptible_timeout(*queue,
  69                         wait_for_tpm_stat_cond(chip, mask, check_cancel,
  70                                                &canceled),
  71                         timeout);
  72                 if (rc > 0) {
  73                         if (canceled)
  74                                 return -ECANCELED;
  75                         return 0;
  76                 }
  77                 if (rc == -ERESTARTSYS && freezing(current)) {
  78                         clear_thread_flag(TIF_SIGPENDING);
  79                         goto again;
  80                 }
  81         } else {
  82                 do {
  83                         usleep_range(TPM_TIMEOUT_USECS_MIN,
  84                                      TPM_TIMEOUT_USECS_MAX);
  85                         status = chip->ops->status(chip);
  86                         if ((status & mask) == mask)
  87                                 return 0;
  88                 } while (time_before(jiffies, stop));
  89         }
  90         return -ETIME;
  91 }
  92
  93 /* Before we attempt to access the TPM we must see that the valid bit is set.
  94  * The specification says that this bit is 0 at reset and remains 0 until the
  95  * 'TPM has gone through its self test and initialization and has established
  96  * correct values in the other bits.'
  97  */
  98 static int wait_startup(struct tpm_chip *chip, int l)
  99 {
 100         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 101         unsigned long stop = jiffies + chip->timeout_a;
 102
 103         do {
 104                 int rc;
 105                 u8 access;
 106
 107                 rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
 108                 if (rc < 0)
 109                         return rc;
 110
 111                 if (access & TPM_ACCESS_VALID)
 112                         return 0;
 113                 tpm_msleep(TPM_TIMEOUT);
 114         } while (time_before(jiffies, stop));
 115         return -1;
 116 }
 117
 118 static bool check_locality(struct tpm_chip *chip, int l)
 119 {
 120         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 121         int rc;
 122         u8 access;
 123
 124         rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
 125         if (rc < 0)
 126                 return false;
 127
 128         if ((access & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID
 129                        | TPM_ACCESS_REQUEST_USE)) ==
 130             (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
 131                 priv->locality = l;
 132                 return true;
 133         }
 134
 135         return false;
 136 }
 137
 138 static int release_locality(struct tpm_chip *chip, int l)
 139 {
 140         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 141
 142         tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
 143
 144         return 0;
 145 }
 146
 147 static int request_locality(struct tpm_chip *chip, int l)
 148 {
 149         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 150         unsigned long stop, timeout;
 151         long rc;
 152
 153         if (check_locality(chip, l))
 154                 return l;
 155
 156         rc = tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_REQUEST_USE);
 157         if (rc < 0)
 158                 return rc;
 159
 160         stop = jiffies + chip->timeout_a;
 161
 162         if (chip->flags & TPM_CHIP_FLAG_IRQ) {
 163 again:
 164                 timeout = stop - jiffies;
 165                 if ((long)timeout <= 0)
 166                         return -1;
 167                 rc = wait_event_interruptible_timeout(priv->int_queue,
 168                                                       (check_locality
 169                                                        (chip, l)),
 170                                                       timeout);
 171                 if (rc > 0)
 172                         return l;
 173                 if (rc == -ERESTARTSYS && freezing(current)) {
 174                         clear_thread_flag(TIF_SIGPENDING);
 175                         goto again;
 176                 }
 177         } else {
 178                 /* wait for burstcount */
 179                 do {
 180                         if (check_locality(chip, l))
 181                                 return l;
 182                         tpm_msleep(TPM_TIMEOUT);
 183                 } while (time_before(jiffies, stop));
 184         }
 185         return -1;
 186 }
 187
 188 static u8 tpm_tis_status(struct tpm_chip *chip)
 189 {
 190         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 191         int rc;
 192         u8 status;
 193
 194         rc = tpm_tis_read8(priv, TPM_STS(priv->locality), &status);
 195         if (rc < 0)
 196                 return 0;
 197
 198         if (unlikely((status & TPM_STS_READ_ZERO) != 0)) {
 199                 if  (!test_and_set_bit(TPM_TIS_INVALID_STATUS, &priv->flags)) {
 200                         /*
 201                          * If this trips, the chances are the read is
 202                          * returning 0xff because the locality hasn't been
 203                          * acquired.  Usually because tpm_try_get_ops() hasn't
 204                          * been called before doing a TPM operation.
 205                          */
 206                         dev_err(&chip->dev, "invalid TPM_STS.x 0x%02x, dumping stack for forensics\n",
 207                                 status);
 208
 209                         /*
 210                          * Dump stack for forensics, as invalid TPM_STS.x could be
 211                          * potentially triggered by impaired tpm_try_get_ops() or
 212                          * tpm_find_get_ops().
 213                          */
 214                         dump_stack();
 215                 }
 216
 217                 return 0;
 218         }
 219
 220         return status;
 221 }
 222
 223 static void tpm_tis_ready(struct tpm_chip *chip)
 224 {
 225         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 226
 227         /* this causes the current command to be aborted */
 228         tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_COMMAND_READY);
 229 }
 230
 231 static int get_burstcount(struct tpm_chip *chip)
 232 {
 233         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 234         unsigned long stop;
 235         int burstcnt, rc;
 236         u32 value;
 237
 238         /* wait for burstcount */
 239         if (chip->flags & TPM_CHIP_FLAG_TPM2)
 240                 stop = jiffies + chip->timeout_a;
 241         else
 242                 stop = jiffies + chip->timeout_d;
 243         do {
 244                 rc = tpm_tis_read32(priv, TPM_STS(priv->locality), &value);
 245                 if (rc < 0)
 246                         return rc;
 247
 248                 burstcnt = (value >> 8) & 0xFFFF;
 249                 if (burstcnt)
 250                         return burstcnt;
 251                 usleep_range(TPM_TIMEOUT_USECS_MIN, TPM_TIMEOUT_USECS_MAX);
 252         } while (time_before(jiffies, stop));
 253         return -EBUSY;
 254 }
 255
 256 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 257 {
 258         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 259         int size = 0, burstcnt, rc;
 260
 261         while (size < count) {
 262                 rc = wait_for_tpm_stat(chip,
 263                                  TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 264                                  chip->timeout_c,
 265                                  &priv->read_queue, true);
 266                 if (rc < 0)
 267                         return rc;
 268                 burstcnt = get_burstcount(chip);
 269                 if (burstcnt < 0) {
 270                         dev_err(&chip->dev, "Unable to read burstcount\n");
 271                         return burstcnt;
 272                 }
 273                 burstcnt = min_t(int, burstcnt, count - size);
 274
 275                 rc = tpm_tis_read_bytes(priv, TPM_DATA_FIFO(priv->locality),
 276                                         burstcnt, buf + size);
 277                 if (rc < 0)
 278                         return rc;
 279
 280                 size += burstcnt;
 281         }
 282         return size;
 283 }
 284
 285 static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
 286 {
 287         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 288         int size = 0;
 289         int status;
 290         u32 expected;
 291
 292         if (count < TPM_HEADER_SIZE) {
 293                 size = -EIO;
 294                 goto out;
 295         }
 296
 297         size = recv_data(chip, buf, TPM_HEADER_SIZE);
 298         /* read first 10 bytes, including tag, paramsize, and result */
 299         if (size < TPM_HEADER_SIZE) {
 300                 dev_err(&chip->dev, "Unable to read header\n");
 301                 goto out;
 302         }
 303
 304         expected = be32_to_cpu(*(__be32 *) (buf + 2));
 305         if (expected > count || expected < TPM_HEADER_SIZE) {
 306                 size = -EIO;
 307                 goto out;
 308         }
 309
 310         size += recv_data(chip, &buf[TPM_HEADER_SIZE],
 311                           expected - TPM_HEADER_SIZE);
 312         if (size < expected) {
 313                 dev_err(&chip->dev, "Unable to read remainder of result\n");
 314                 size = -ETIME;
 315                 goto out;
 316         }
 317
 318         if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
 319                                 &priv->int_queue, false) < 0) {
 320                 size = -ETIME;
 321                 goto out;
 322         }
 323         status = tpm_tis_status(chip);
 324         if (status & TPM_STS_DATA_AVAIL) {      /* retry? */
 325                 dev_err(&chip->dev, "Error left over data\n");
 326                 size = -EIO;
 327                 goto out;
 328         }
 329
 330 out:
 331         tpm_tis_ready(chip);
 332         return size;
 333 }
 334
 335 /*
 336  * If interrupts are used (signaled by an irq set in the vendor structure)
 337  * tpm.c can skip polling for the data to be available as the interrupt is
 338  * waited for here
 339  */
 340 static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len)
 341 {
 342         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 343         int rc, status, burstcnt;
 344         size_t count = 0;
 345         bool itpm = priv->flags & TPM_TIS_ITPM_WORKAROUND;
 346
 347         status = tpm_tis_status(chip);
 348         if ((status & TPM_STS_COMMAND_READY) == 0) {
 349                 tpm_tis_ready(chip);
 350                 if (wait_for_tpm_stat
 351                     (chip, TPM_STS_COMMAND_READY, chip->timeout_b,
 352                      &priv->int_queue, false) < 0) {
 353                         rc = -ETIME;
 354                         goto out_err;
 355                 }
 356         }
 357
 358         while (count < len - 1) {
 359                 burstcnt = get_burstcount(chip);
 360                 if (burstcnt < 0) {
 361                         dev_err(&chip->dev, "Unable to read burstcount\n");
 362                         rc = burstcnt;
 363                         goto out_err;
 364                 }
 365                 burstcnt = min_t(int, burstcnt, len - count - 1);
 366                 rc = tpm_tis_write_bytes(priv, TPM_DATA_FIFO(priv->locality),
 367                                          burstcnt, buf + count);
 368                 if (rc < 0)
 369                         goto out_err;
 370
 371                 count += burstcnt;
 372
 373                 if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
 374                                         &priv->int_queue, false) < 0) {
 375                         rc = -ETIME;
 376                         goto out_err;
 377                 }
 378                 status = tpm_tis_status(chip);
 379                 if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
 380                         rc = -EIO;
 381                         goto out_err;
 382                 }
 383         }
 384
 385         /* write last byte */
 386         rc = tpm_tis_write8(priv, TPM_DATA_FIFO(priv->locality), buf[count]);
 387         if (rc < 0)
 388                 goto out_err;
 389
 390         if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
 391                                 &priv->int_queue, false) < 0) {
 392                 rc = -ETIME;
 393                 goto out_err;
 394         }
 395         status = tpm_tis_status(chip);
 396         if (!itpm && (status & TPM_STS_DATA_EXPECT) != 0) {
 397                 rc = -EIO;
 398                 goto out_err;
 399         }
 400
 401         return 0;
 402
 403 out_err:
 404         tpm_tis_ready(chip);
 405         return rc;
 406 }
 407
 408 static void disable_interrupts(struct tpm_chip *chip)
 409 {
 410         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 411         u32 intmask;
 412         int rc;
 413
 414         if (priv->irq == 0)
 415                 return;
 416
 417         rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
 418         if (rc < 0)
 419                 intmask = 0;
 420
 421         intmask &= ~TPM_GLOBAL_INT_ENABLE;
 422         rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
 423
 424         devm_free_irq(chip->dev.parent, priv->irq, chip);
 425         priv->irq = 0;
 426         chip->flags &= ~TPM_CHIP_FLAG_IRQ;
 427 }
 428
 429 /*
 430  * If interrupts are used (signaled by an irq set in the vendor structure)
 431  * tpm.c can skip polling for the data to be available as the interrupt is
 432  * waited for here
 433  */
 434 static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len)
 435 {
 436         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 437         int rc;
 438         u32 ordinal;
 439         unsigned long dur;
 440
 441         rc = tpm_tis_send_data(chip, buf, len);
 442         if (rc < 0)
 443                 return rc;
 444
 445         /* go and do it */
 446         rc = tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_GO);
 447         if (rc < 0)
 448                 goto out_err;
 449
 450         if (chip->flags & TPM_CHIP_FLAG_IRQ) {
 451                 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 452
 453                 dur = tpm_calc_ordinal_duration(chip, ordinal);
 454                 if (wait_for_tpm_stat
 455                     (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur,
 456                      &priv->read_queue, false) < 0) {
 457                         rc = -ETIME;
 458                         goto out_err;
 459                 }
 460         }
 461         return 0;
 462 out_err:
 463         tpm_tis_ready(chip);
 464         return rc;
 465 }
 466
 467 static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
 468 {
 469         int rc, irq;
 470         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 471
 472         if (!(chip->flags & TPM_CHIP_FLAG_IRQ) || priv->irq_tested)
 473                 return tpm_tis_send_main(chip, buf, len);
 474
 475         /* Verify receipt of the expected IRQ */
 476         irq = priv->irq;
 477         priv->irq = 0;
 478         chip->flags &= ~TPM_CHIP_FLAG_IRQ;
 479         rc = tpm_tis_send_main(chip, buf, len);
 480         priv->irq = irq;
 481         chip->flags |= TPM_CHIP_FLAG_IRQ;
 482         if (!priv->irq_tested)
 483                 tpm_msleep(1);
 484         if (!priv->irq_tested)
 485                 disable_interrupts(chip);
 486         priv->irq_tested = true;
 487         return rc;
 488 }
 489
 490 struct tis_vendor_durations_override {
 491         u32 did_vid;
 492         struct tpm1_version version;
 493         unsigned long durations[3];
 494 };
 495
 496 static const struct  tis_vendor_durations_override vendor_dur_overrides[] = {
 497         /* STMicroelectronics 0x104a */
 498         { 0x0000104a,
 499           { 1, 2, 8, 28 },
 500           { (2 * 60 * HZ), (2 * 60 * HZ), (2 * 60 * HZ) } },
 501 };
 502
 503 static void tpm_tis_update_durations(struct tpm_chip *chip,
 504                                      unsigned long *duration_cap)
 505 {
 506         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 507         struct tpm1_version *version;
 508         u32 did_vid;
 509         int i, rc;
 510         cap_t cap;
 511
 512         chip->duration_adjusted = false;
 513
 514         if (chip->ops->clk_enable != NULL)
 515                 chip->ops->clk_enable(chip, true);
 516
 517         rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid);
 518         if (rc < 0) {
 519                 dev_warn(&chip->dev, "%s: failed to read did_vid. %d\n",
 520                          __func__, rc);
 521                 goto out;
 522         }
 523
 524         /* Try to get a TPM version 1.2 or 1.1 TPM_CAP_VERSION_INFO */
 525         rc = tpm1_getcap(chip, TPM_CAP_VERSION_1_2, &cap,
 526                          "attempting to determine the 1.2 version",
 527                          sizeof(cap.version2));
 528         if (!rc) {
 529                 version = &cap.version2.version;
 530         } else {
 531                 rc = tpm1_getcap(chip, TPM_CAP_VERSION_1_1, &cap,
 532                                  "attempting to determine the 1.1 version",
 533                                  sizeof(cap.version1));
 534
 535                 if (rc)
 536                         goto out;
 537
 538                 version = &cap.version1;
 539         }
 540
 541         for (i = 0; i != ARRAY_SIZE(vendor_dur_overrides); i++) {
 542                 if (vendor_dur_overrides[i].did_vid != did_vid)
 543                         continue;
 544
 545                 if ((version->major ==
 546                      vendor_dur_overrides[i].version.major) &&
 547                     (version->minor ==
 548                      vendor_dur_overrides[i].version.minor) &&
 549                     (version->rev_major ==
 550                      vendor_dur_overrides[i].version.rev_major) &&
 551                     (version->rev_minor ==
 552                      vendor_dur_overrides[i].version.rev_minor)) {
 553
 554                         memcpy(duration_cap,
 555                                vendor_dur_overrides[i].durations,
 556                                sizeof(vendor_dur_overrides[i].durations));
 557
 558                         chip->duration_adjusted = true;
 559                         goto out;
 560                 }
 561         }
 562
 563 out:
 564         if (chip->ops->clk_enable != NULL)
 565                 chip->ops->clk_enable(chip, false);
 566 }
 567
 568 struct tis_vendor_timeout_override {
 569         u32 did_vid;
 570         unsigned long timeout_us[4];
 571 };
 572
 573 static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = {
 574         /* Atmel 3204 */
 575         { 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000),
 576                         (TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } },
 577 };
 578
 579 static void tpm_tis_update_timeouts(struct tpm_chip *chip,
 580                                     unsigned long *timeout_cap)
 581 {
 582         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 583         int i, rc;
 584         u32 did_vid;
 585
 586         chip->timeout_adjusted = false;
 587
 588         if (chip->ops->clk_enable != NULL)
 589                 chip->ops->clk_enable(chip, true);
 590
 591         rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid);
 592         if (rc < 0) {
 593                 dev_warn(&chip->dev, "%s: failed to read did_vid: %d\n",
 594                          __func__, rc);
 595                 goto out;
 596         }
 597
 598         for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
 599                 if (vendor_timeout_overrides[i].did_vid != did_vid)
 600                         continue;
 601                 memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
 602                        sizeof(vendor_timeout_overrides[i].timeout_us));
 603                 chip->timeout_adjusted = true;
 604         }
 605
 606 out:
 607         if (chip->ops->clk_enable != NULL)
 608                 chip->ops->clk_enable(chip, false);
 609
 610         return;
 611 }
 612
 613 /*
 614  * Early probing for iTPM with STS_DATA_EXPECT flaw.
 615  * Try sending command without itpm flag set and if that
 616  * fails, repeat with itpm flag set.
 617  */
 618 static int probe_itpm(struct tpm_chip *chip)
 619 {
 620         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 621         int rc = 0;
 622         static const u8 cmd_getticks[] = {
 623                 0x00, 0xc1, 0x00, 0x00, 0x00, 0x0a,
 624                 0x00, 0x00, 0x00, 0xf1
 625         };
 626         size_t len = sizeof(cmd_getticks);
 627         u16 vendor;
 628
 629         if (priv->flags & TPM_TIS_ITPM_WORKAROUND)
 630                 return 0;
 631
 632         rc = tpm_tis_read16(priv, TPM_DID_VID(0), &vendor);
 633         if (rc < 0)
 634                 return rc;
 635
 636         /* probe only iTPMS */
 637         if (vendor != TPM_VID_INTEL)
 638                 return 0;
 639
 640         if (request_locality(chip, 0) != 0)
 641                 return -EBUSY;
 642
 643         rc = tpm_tis_send_data(chip, cmd_getticks, len);
 644         if (rc == 0)
 645                 goto out;
 646
 647         tpm_tis_ready(chip);
 648
 649         priv->flags |= TPM_TIS_ITPM_WORKAROUND;
 650
 651         rc = tpm_tis_send_data(chip, cmd_getticks, len);
 652         if (rc == 0)
 653                 dev_info(&chip->dev, "Detected an iTPM.\n");
 654         else {
 655                 priv->flags &= ~TPM_TIS_ITPM_WORKAROUND;
 656                 rc = -EFAULT;
 657         }
 658
 659 out:
 660         tpm_tis_ready(chip);
 661         release_locality(chip, priv->locality);
 662
 663         return rc;
 664 }
 665
 666 static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
 667 {
 668         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 669
 670         switch (priv->manufacturer_id) {
 671         case TPM_VID_WINBOND:
 672                 return ((status == TPM_STS_VALID) ||
 673                         (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
 674         case TPM_VID_STM:
 675                 return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
 676         default:
 677                 return (status == TPM_STS_COMMAND_READY);
 678         }
 679 }
 680
 681 static irqreturn_t tis_int_handler(int dummy, void *dev_id)
 682 {
 683         struct tpm_chip *chip = dev_id;
 684         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 685         u32 interrupt;
 686         int i, rc;
 687
 688         rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
 689         if (rc < 0)
 690                 return IRQ_NONE;
 691
 692         if (interrupt == 0)
 693                 return IRQ_NONE;
 694
 695         priv->irq_tested = true;
 696         if (interrupt & TPM_INTF_DATA_AVAIL_INT)
 697                 wake_up_interruptible(&priv->read_queue);
 698         if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
 699                 for (i = 0; i < 5; i++)
 700                         if (check_locality(chip, i))
 701                                 break;
 702         if (interrupt &
 703             (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
 704              TPM_INTF_CMD_READY_INT))
 705                 wake_up_interruptible(&priv->int_queue);
 706
 707         /* Clear interrupts handled with TPM_EOI */
 708         rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), interrupt);
 709         if (rc < 0)
 710                 return IRQ_NONE;
 711
 712         tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
 713         return IRQ_HANDLED;
 714 }
 715
 716 static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
 717 {
 718         const char *desc = "attempting to generate an interrupt";
 719         u32 cap2;
 720         cap_t cap;
 721         int ret;
 722
 723         ret = request_locality(chip, 0);
 724         if (ret < 0)
 725                 return ret;
 726
 727         if (chip->flags & TPM_CHIP_FLAG_TPM2)
 728                 ret = tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);
 729         else
 730                 ret = tpm1_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc, 0);
 731
 732         release_locality(chip, 0);
 733
 734         return ret;
 735 }
 736
 737 /* Register the IRQ and issue a command that will cause an interrupt. If an
 738  * irq is seen then leave the chip setup for IRQ operation, otherwise reverse
 739  * everything and leave in polling mode. Returns 0 on success.
 740  */
 741 static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
 742                                     int flags, int irq)
 743 {
 744         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 745         u8 original_int_vec;
 746         int rc;
 747         u32 int_status;
 748
 749         if (devm_request_irq(chip->dev.parent, irq, tis_int_handler, flags,
 750                              dev_name(&chip->dev), chip) != 0) {
 751                 dev_info(&chip->dev, "Unable to request irq: %d for probe\n",
 752                          irq);
 753                 return -1;
 754         }
 755         priv->irq = irq;
 756
 757         rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
 758                            &original_int_vec);
 759         if (rc < 0)
 760                 return rc;
 761
 762         rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
 763         if (rc < 0)
 764                 return rc;
 765
 766         rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
 767         if (rc < 0)
 768                 return rc;
 769
 770         /* Clear all existing */
 771         rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
 772         if (rc < 0)
 773                 return rc;
 774
 775         /* Turn on */
 776         rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality),
 777                              intmask | TPM_GLOBAL_INT_ENABLE);
 778         if (rc < 0)
 779                 return rc;
 780
 781         priv->irq_tested = false;
 782
 783         /* Generate an interrupt by having the core call through to
 784          * tpm_tis_send
 785          */
 786         rc = tpm_tis_gen_interrupt(chip);
 787         if (rc < 0)
 788                 return rc;
 789
 790         /* tpm_tis_send will either confirm the interrupt is working or it
 791          * will call disable_irq which undoes all of the above.
 792          */
 793         if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
 794                 rc = tpm_tis_write8(priv, original_int_vec,
 795                                 TPM_INT_VECTOR(priv->locality));
 796                 if (rc < 0)
 797                         return rc;
 798
 799                 return 1;
 800         }
 801
 802         return 0;
 803 }
 804
 805 /* Try to find the IRQ the TPM is using. This is for legacy x86 systems that
 806  * do not have ACPI/etc. We typically expect the interrupt to be declared if
 807  * present.
 808  */
 809 static void tpm_tis_probe_irq(struct tpm_chip *chip, u32 intmask)
 810 {
 811         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 812         u8 original_int_vec;
 813         int i, rc;
 814
 815         rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
 816                            &original_int_vec);
 817         if (rc < 0)
 818                 return;
 819
 820         if (!original_int_vec) {
 821                 if (IS_ENABLED(CONFIG_X86))
 822                         for (i = 3; i <= 15; i++)
 823                                 if (!tpm_tis_probe_irq_single(chip, intmask, 0,
 824                                                               i))
 825                                         return;
 826         } else if (!tpm_tis_probe_irq_single(chip, intmask, 0,
 827                                              original_int_vec))
 828                 return;
 829 }
 830
 831 void tpm_tis_remove(struct tpm_chip *chip)
 832 {
 833         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 834         u32 reg = TPM_INT_ENABLE(priv->locality);
 835         u32 interrupt;
 836         int rc;
 837
 838         tpm_tis_clkrun_enable(chip, true);
 839
 840         rc = tpm_tis_read32(priv, reg, &interrupt);
 841         if (rc < 0)
 842                 interrupt = 0;
 843
 844         tpm_tis_write32(priv, reg, ~TPM_GLOBAL_INT_ENABLE & interrupt);
 845
 846         tpm_tis_clkrun_enable(chip, false);
 847
 848         if (priv->ilb_base_addr)
 849                 iounmap(priv->ilb_base_addr);
 850 }
 851 EXPORT_SYMBOL_GPL(tpm_tis_remove);
 852
 853 /**
 854  * tpm_tis_clkrun_enable() - Keep clkrun protocol disabled for entire duration
 855  *                           of a single TPM command
 856  * @chip:       TPM chip to use
 857  * @value:      1 - Disable CLKRUN protocol, so that clocks are free running
 858  *              0 - Enable CLKRUN protocol
 859  * Call this function directly in tpm_tis_remove() in error or driver removal
 860  * path, since the chip->ops is set to NULL in tpm_chip_unregister().
 861  */
 862 static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value)
 863 {
 864         struct tpm_tis_data *data = dev_get_drvdata(&chip->dev);
 865         u32 clkrun_val;
 866
 867         if (!IS_ENABLED(CONFIG_X86) || !is_bsw() ||
 868             !data->ilb_base_addr)
 869                 return;
 870
 871         if (value) {
 872                 data->clkrun_enabled++;
 873                 if (data->clkrun_enabled > 1)
 874                         return;
 875                 clkrun_val = ioread32(data->ilb_base_addr + LPC_CNTRL_OFFSET);
 876
 877                 /* Disable LPC CLKRUN# */
 878                 clkrun_val &= ~LPC_CLKRUN_EN;
 879                 iowrite32(clkrun_val, data->ilb_base_addr + LPC_CNTRL_OFFSET);
 880
 881                 /*
 882                  * Write any random value on port 0x80 which is on LPC, to make
 883                  * sure LPC clock is running before sending any TPM command.
 884                  */
 885                 outb(0xCC, 0x80);
 886         } else {
 887                 data->clkrun_enabled--;
 888                 if (data->clkrun_enabled)
 889                         return;
 890
 891                 clkrun_val = ioread32(data->ilb_base_addr + LPC_CNTRL_OFFSET);
 892
 893                 /* Enable LPC CLKRUN# */
 894                 clkrun_val |= LPC_CLKRUN_EN;
 895                 iowrite32(clkrun_val, data->ilb_base_addr + LPC_CNTRL_OFFSET);
 896
 897                 /*
 898                  * Write any random value on port 0x80 which is on LPC, to make
 899                  * sure LPC clock is running before sending any TPM command.
 900                  */
 901                 outb(0xCC, 0x80);
 902         }
 903 }
 904
 905 static const struct tpm_class_ops tpm_tis = {
 906         .flags = TPM_OPS_AUTO_STARTUP,
 907         .status = tpm_tis_status,
 908         .recv = tpm_tis_recv,
 909         .send = tpm_tis_send,
 910         .cancel = tpm_tis_ready,
 911         .update_timeouts = tpm_tis_update_timeouts,
 912         .update_durations = tpm_tis_update_durations,
 913         .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 914         .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 915         .req_canceled = tpm_tis_req_canceled,
 916         .request_locality = request_locality,
 917         .relinquish_locality = release_locality,
 918         .clk_enable = tpm_tis_clkrun_enable,
 919 };
 920
 921 int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 922                       const struct tpm_tis_phy_ops *phy_ops,
 923                       acpi_handle acpi_dev_handle)
 924 {
 925         u32 vendor;
 926         u32 intfcaps;
 927         u32 intmask;
 928         u32 clkrun_val;
 929         u8 rid;
 930         int rc, probe;
 931         struct tpm_chip *chip;
 932
 933         chip = tpmm_chip_alloc(dev, &tpm_tis);
 934         if (IS_ERR(chip))
 935                 return PTR_ERR(chip);
 936
 937 #ifdef CONFIG_ACPI
 938         chip->acpi_dev_handle = acpi_dev_handle;
 939 #endif
 940
 941         chip->hwrng.quality = priv->rng_quality;
 942
 943         /* Maximum timeouts */
 944         chip->timeout_a = msecs_to_jiffies(TIS_TIMEOUT_A_MAX);
 945         chip->timeout_b = msecs_to_jiffies(TIS_TIMEOUT_B_MAX);
 946         chip->timeout_c = msecs_to_jiffies(TIS_TIMEOUT_C_MAX);
 947         chip->timeout_d = msecs_to_jiffies(TIS_TIMEOUT_D_MAX);
 948         priv->phy_ops = phy_ops;
 949         dev_set_drvdata(&chip->dev, priv);
 950
 951         if (is_bsw()) {
 952                 priv->ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR,
 953                                         ILB_REMAP_SIZE);
 954                 if (!priv->ilb_base_addr)
 955                         return -ENOMEM;
 956
 957                 clkrun_val = ioread32(priv->ilb_base_addr + LPC_CNTRL_OFFSET);
 958                 /* Check if CLKRUN# is already not enabled in the LPC bus */
 959                 if (!(clkrun_val & LPC_CLKRUN_EN)) {
 960                         iounmap(priv->ilb_base_addr);
 961                         priv->ilb_base_addr = NULL;
 962                 }
 963         }
 964
 965         if (chip->ops->clk_enable != NULL)
 966                 chip->ops->clk_enable(chip, true);
 967
 968         if (wait_startup(chip, 0) != 0) {
 969                 rc = -ENODEV;
 970                 goto out_err;
 971         }
 972
 973         /* Take control of the TPM's interrupt hardware and shut it off */
 974         rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
 975         if (rc < 0)
 976                 goto out_err;
 977
 978         intmask |= TPM_INTF_CMD_READY_INT | TPM_INTF_LOCALITY_CHANGE_INT |
 979                    TPM_INTF_DATA_AVAIL_INT | TPM_INTF_STS_VALID_INT;
 980         intmask &= ~TPM_GLOBAL_INT_ENABLE;
 981         tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
 982
 983         rc = tpm_chip_start(chip);
 984         if (rc)
 985                 goto out_err;
 986         rc = tpm2_probe(chip);
 987         tpm_chip_stop(chip);
 988         if (rc)
 989                 goto out_err;
 990
 991         rc = tpm_tis_read32(priv, TPM_DID_VID(0), &vendor);
 992         if (rc < 0)
 993                 goto out_err;
 994
 995         priv->manufacturer_id = vendor;
 996
 997         rc = tpm_tis_read8(priv, TPM_RID(0), &rid);
 998         if (rc < 0)
 999                 goto out_err;
1000
1001         dev_info(dev, "%s TPM (device-id 0x%X, rev-id %d)\n",
1002                  (chip->flags & TPM_CHIP_FLAG_TPM2) ? "2.0" : "1.2",
1003                  vendor >> 16, rid);
1004
1005         probe = probe_itpm(chip);
1006         if (probe < 0) {
1007                 rc = -ENODEV;
1008                 goto out_err;
1009         }
1010
1011         /* Figure out the capabilities */
1012         rc = tpm_tis_read32(priv, TPM_INTF_CAPS(priv->locality), &intfcaps);
1013         if (rc < 0)
1014                 goto out_err;
1015
1016         dev_dbg(dev, "TPM interface capabilities (0x%x):\n",
1017                 intfcaps);
1018         if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
1019                 dev_dbg(dev, "\tBurst Count Static\n");
1020         if (intfcaps & TPM_INTF_CMD_READY_INT)
1021                 dev_dbg(dev, "\tCommand Ready Int Support\n");
1022         if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
1023                 dev_dbg(dev, "\tInterrupt Edge Falling\n");
1024         if (intfcaps & TPM_INTF_INT_EDGE_RISING)
1025                 dev_dbg(dev, "\tInterrupt Edge Rising\n");
1026         if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
1027                 dev_dbg(dev, "\tInterrupt Level Low\n");
1028         if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
1029                 dev_dbg(dev, "\tInterrupt Level High\n");
1030         if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT)
1031                 dev_dbg(dev, "\tLocality Change Int Support\n");
1032         if (intfcaps & TPM_INTF_STS_VALID_INT)
1033                 dev_dbg(dev, "\tSts Valid Int Support\n");
1034         if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
1035                 dev_dbg(dev, "\tData Avail Int Support\n");
1036
1037         /* INTERRUPT Setup */
1038         init_waitqueue_head(&priv->read_queue);
1039         init_waitqueue_head(&priv->int_queue);
1040         if (irq != -1) {
1041                 /*
1042                  * Before doing irq testing issue a command to the TPM in polling mode
1043                  * to make sure it works. May as well use that command to set the
1044                  * proper timeouts for the driver.
1045                  */
1046
1047                 rc = request_locality(chip, 0);
1048                 if (rc < 0)
1049                         goto out_err;
1050
1051                 rc = tpm_get_timeouts(chip);
1052
1053                 release_locality(chip, 0);
1054
1055                 if (rc) {
1056                         dev_err(dev, "Could not get TPM timeouts and durations\n");
1057                         rc = -ENODEV;
1058                         goto out_err;
1059                 }
1060
1061                 if (irq) {
1062                         tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED,
1063                                                  irq);
1064                         if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
1065                                 dev_err(&chip->dev, FW_BUG
1066                                         "TPM interrupt not working, polling instead\n");
1067
1068                                 disable_interrupts(chip);
1069                         }
1070                 } else {
1071                         tpm_tis_probe_irq(chip, intmask);
1072                 }
1073         }
1074
1075         rc = tpm_chip_register(chip);
1076         if (rc)
1077                 goto out_err;
1078
1079         if (chip->ops->clk_enable != NULL)
1080                 chip->ops->clk_enable(chip, false);
1081
1082         return 0;
1083 out_err:
1084         if (chip->ops->clk_enable != NULL)
1085                 chip->ops->clk_enable(chip, false);
1086
1087         tpm_tis_remove(chip);
1088
1089         return rc;
1090 }
1091 EXPORT_SYMBOL_GPL(tpm_tis_core_init);
1092
1093 #ifdef CONFIG_PM_SLEEP
1094 static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
1095 {
1096         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
1097         u32 intmask;
1098         int rc;
1099
1100         if (chip->ops->clk_enable != NULL)
1101                 chip->ops->clk_enable(chip, true);
1102
1103         /* reenable interrupts that device may have lost or
1104          * BIOS/firmware may have disabled
1105          */
1106         rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), priv->irq);
1107         if (rc < 0)
1108                 goto out;
1109
1110         rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
1111         if (rc < 0)
1112                 goto out;
1113
1114         intmask |= TPM_INTF_CMD_READY_INT
1115             | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
1116             | TPM_INTF_STS_VALID_INT | TPM_GLOBAL_INT_ENABLE;
1117
1118         tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
1119
1120 out:
1121         if (chip->ops->clk_enable != NULL)
1122                 chip->ops->clk_enable(chip, false);
1123
1124         return;
1125 }
1126
1127 int tpm_tis_resume(struct device *dev)
1128 {
1129         struct tpm_chip *chip = dev_get_drvdata(dev);
1130         int ret;
1131
1132         if (chip->flags & TPM_CHIP_FLAG_IRQ)
1133                 tpm_tis_reenable_interrupts(chip);
1134
1135         ret = tpm_pm_resume(dev);
1136         if (ret)
1137                 return ret;
1138
1139         /*
1140          * TPM 1.2 requires self-test on resume. This function actually returns
1141          * an error code but for unknown reason it isn't handled.
1142          */
1143         if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
1144                 ret = request_locality(chip, 0);
1145                 if (ret < 0)
1146                         return ret;
1147
1148                 tpm1_do_selftest(chip);
1149
1150                 release_locality(chip, 0);
1151         }
1152
1153         return 0;
1154 }
1155 EXPORT_SYMBOL_GPL(tpm_tis_resume);
1156 #endif
1157
1158 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1159 MODULE_DESCRIPTION("TPM Driver");
1160 MODULE_VERSION("2.0");
1161 MODULE_LICENSE("GPL");