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