drivers/char/tpm/tpm_tis_core.c

   1 /*
   2  * Copyright (C) 2005, 2006 IBM Corporation
   3  * Copyright (C) 2014, 2015 Intel Corporation
   4  *
   5  * Authors:
   6  * Leendert van Doorn <leendert@watson.ibm.com>
   7  * Kylene Hall <kjhall@us.ibm.com>
   8  *
   9  * Maintained by: <tpmdd-devel@lists.sourceforge.net>
  10  *
  11  * Device driver for TCG/TCPA TPM (trusted platform module).
  12  * Specifications at www.trustedcomputinggroup.org
  13  *
  14  * This device driver implements the TPM interface as defined in
  15  * the TCG TPM Interface Spec version 1.2, revision 1.0.
  16  *
  17  * This program is free software; you can redistribute it and/or
  18  * modify it under the terms of the GNU General Public License as
  19  * published by the Free Software Foundation, version 2 of the
  20  * License.
  21  */
  22 #include <linux/init.h>
  23 #include <linux/module.h>
  24 #include <linux/moduleparam.h>
  25 #include <linux/pnp.h>
  26 #include <linux/slab.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/wait.h>
  29 #include <linux/acpi.h>
  30 #include <linux/freezer.h>
  31 #include "tpm.h"
  32 #include "tpm_tis_core.h"
  33
  34 static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value);
  35
  36 static bool wait_for_tpm_stat_cond(struct tpm_chip *chip, u8 mask,
  37                                         bool check_cancel, bool *canceled)
  38 {
  39         u8 status = chip->ops->status(chip);
  40
  41         *canceled = false;
  42         if ((status & mask) == mask)
  43                 return true;
  44         if (check_cancel && chip->ops->req_canceled(chip, status)) {
  45                 *canceled = true;
  46                 return true;
  47         }
  48         return false;
  49 }
  50
  51 static int wait_for_tpm_stat(struct tpm_chip *chip, u8 mask,
  52                 unsigned long timeout, wait_queue_head_t *queue,
  53                 bool check_cancel)
  54 {
  55         unsigned long stop;
  56         long rc;
  57         u8 status;
  58         bool canceled = false;
  59
  60         /* check current status */
  61         status = chip->ops->status(chip);
  62         if ((status & mask) == mask)
  63                 return 0;
  64
  65         stop = jiffies + timeout;
  66
  67         if (chip->flags & TPM_CHIP_FLAG_IRQ) {
  68 again:
  69                 timeout = stop - jiffies;
  70                 if ((long)timeout <= 0)
  71                         return -ETIME;
  72                 rc = wait_event_interruptible_timeout(*queue,
  73                         wait_for_tpm_stat_cond(chip, mask, check_cancel,
  74                                                &canceled),
  75                         timeout);
  76                 if (rc > 0) {
  77                         if (canceled)
  78                                 return -ECANCELED;
  79                         return 0;
  80                 }
  81                 if (rc == -ERESTARTSYS && freezing(current)) {
  82                         clear_thread_flag(TIF_SIGPENDING);
  83                         goto again;
  84                 }
  85         } else {
  86                 do {
  87                         usleep_range(TPM_TIMEOUT_USECS_MIN,
  88                                      TPM_TIMEOUT_USECS_MAX);
  89                         status = chip->ops->status(chip);
  90                         if ((status & mask) == mask)
  91                                 return 0;
  92                 } while (time_before(jiffies, stop));
  93         }
  94         return -ETIME;
  95 }
  96
  97 /* Before we attempt to access the TPM we must see that the valid bit is set.
  98  * The specification says that this bit is 0 at reset and remains 0 until the
  99  * 'TPM has gone through its self test and initialization and has established
 100  * correct values in the other bits.'
 101  */
 102 static int wait_startup(struct tpm_chip *chip, int l)
 103 {
 104         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 105         unsigned long stop = jiffies + chip->timeout_a;
 106
 107         do {
 108                 int rc;
 109                 u8 access;
 110
 111                 rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
 112                 if (rc < 0)
 113                         return rc;
 114
 115                 if (access & TPM_ACCESS_VALID)
 116                         return 0;
 117                 tpm_msleep(TPM_TIMEOUT);
 118         } while (time_before(jiffies, stop));
 119         return -1;
 120 }
 121
 122 static bool check_locality(struct tpm_chip *chip, int l)
 123 {
 124         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 125         int rc;
 126         u8 access;
 127
 128         rc = tpm_tis_read8(priv, TPM_ACCESS(l), &access);
 129         if (rc < 0)
 130                 return false;
 131
 132         if ((access & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID
 133                        | TPM_ACCESS_REQUEST_USE)) ==
 134             (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) {
 135                 priv->locality = l;
 136                 return true;
 137         }
 138
 139         return false;
 140 }
 141
 142 static int release_locality(struct tpm_chip *chip, int l)
 143 {
 144         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 145
 146         tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_ACTIVE_LOCALITY);
 147
 148         return 0;
 149 }
 150
 151 static int request_locality(struct tpm_chip *chip, int l)
 152 {
 153         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 154         unsigned long stop, timeout;
 155         long rc;
 156
 157         if (check_locality(chip, l))
 158                 return l;
 159
 160         rc = tpm_tis_write8(priv, TPM_ACCESS(l), TPM_ACCESS_REQUEST_USE);
 161         if (rc < 0)
 162                 return rc;
 163
 164         stop = jiffies + chip->timeout_a;
 165
 166         if (chip->flags & TPM_CHIP_FLAG_IRQ) {
 167 again:
 168                 timeout = stop - jiffies;
 169                 if ((long)timeout <= 0)
 170                         return -1;
 171                 rc = wait_event_interruptible_timeout(priv->int_queue,
 172                                                       (check_locality
 173                                                        (chip, l)),
 174                                                       timeout);
 175                 if (rc > 0)
 176                         return l;
 177                 if (rc == -ERESTARTSYS && freezing(current)) {
 178                         clear_thread_flag(TIF_SIGPENDING);
 179                         goto again;
 180                 }
 181         } else {
 182                 /* wait for burstcount */
 183                 do {
 184                         if (check_locality(chip, l))
 185                                 return l;
 186                         tpm_msleep(TPM_TIMEOUT);
 187                 } while (time_before(jiffies, stop));
 188         }
 189         return -1;
 190 }
 191
 192 static u8 tpm_tis_status(struct tpm_chip *chip)
 193 {
 194         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 195         int rc;
 196         u8 status;
 197
 198         rc = tpm_tis_read8(priv, TPM_STS(priv->locality), &status);
 199         if (rc < 0)
 200                 return 0;
 201
 202         return status;
 203 }
 204
 205 static void tpm_tis_ready(struct tpm_chip *chip)
 206 {
 207         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 208
 209         /* this causes the current command to be aborted */
 210         tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_COMMAND_READY);
 211 }
 212
 213 static int get_burstcount(struct tpm_chip *chip)
 214 {
 215         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 216         unsigned long stop;
 217         int burstcnt, rc;
 218         u32 value;
 219
 220         /* wait for burstcount */
 221         if (chip->flags & TPM_CHIP_FLAG_TPM2)
 222                 stop = jiffies + chip->timeout_a;
 223         else
 224                 stop = jiffies + chip->timeout_d;
 225         do {
 226                 rc = tpm_tis_read32(priv, TPM_STS(priv->locality), &value);
 227                 if (rc < 0)
 228                         return rc;
 229
 230                 burstcnt = (value >> 8) & 0xFFFF;
 231                 if (burstcnt)
 232                         return burstcnt;
 233                 usleep_range(TPM_TIMEOUT_USECS_MIN, TPM_TIMEOUT_USECS_MAX);
 234         } while (time_before(jiffies, stop));
 235         return -EBUSY;
 236 }
 237
 238 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 239 {
 240         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 241         int size = 0, burstcnt, rc;
 242
 243         while (size < count) {
 244                 rc = wait_for_tpm_stat(chip,
 245                                  TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 246                                  chip->timeout_c,
 247                                  &priv->read_queue, true);
 248                 if (rc < 0)
 249                         return rc;
 250                 burstcnt = get_burstcount(chip);
 251                 if (burstcnt < 0) {
 252                         dev_err(&chip->dev, "Unable to read burstcount\n");
 253                         return burstcnt;
 254                 }
 255                 burstcnt = min_t(int, burstcnt, count - size);
 256
 257                 rc = tpm_tis_read_bytes(priv, TPM_DATA_FIFO(priv->locality),
 258                                         burstcnt, buf + size);
 259                 if (rc < 0)
 260                         return rc;
 261
 262                 size += burstcnt;
 263         }
 264         return size;
 265 }
 266
 267 static int tpm_tis_recv(struct tpm_chip *chip, u8 *buf, size_t count)
 268 {
 269         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 270         int size = 0;
 271         int status;
 272         u32 expected;
 273
 274         if (count < TPM_HEADER_SIZE) {
 275                 size = -EIO;
 276                 goto out;
 277         }
 278
 279         size = recv_data(chip, buf, TPM_HEADER_SIZE);
 280         /* read first 10 bytes, including tag, paramsize, and result */
 281         if (size < TPM_HEADER_SIZE) {
 282                 dev_err(&chip->dev, "Unable to read header\n");
 283                 goto out;
 284         }
 285
 286         expected = be32_to_cpu(*(__be32 *) (buf + 2));
 287         if (expected > count || expected < TPM_HEADER_SIZE) {
 288                 size = -EIO;
 289                 goto out;
 290         }
 291
 292         size += recv_data(chip, &buf[TPM_HEADER_SIZE],
 293                           expected - TPM_HEADER_SIZE);
 294         if (size < expected) {
 295                 dev_err(&chip->dev, "Unable to read remainder of result\n");
 296                 size = -ETIME;
 297                 goto out;
 298         }
 299
 300         if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
 301                                 &priv->int_queue, false) < 0) {
 302                 size = -ETIME;
 303                 goto out;
 304         }
 305         status = tpm_tis_status(chip);
 306         if (status & TPM_STS_DATA_AVAIL) {      /* retry? */
 307                 dev_err(&chip->dev, "Error left over data\n");
 308                 size = -EIO;
 309                 goto out;
 310         }
 311
 312 out:
 313         tpm_tis_ready(chip);
 314         return size;
 315 }
 316
 317 /*
 318  * If interrupts are used (signaled by an irq set in the vendor structure)
 319  * tpm.c can skip polling for the data to be available as the interrupt is
 320  * waited for here
 321  */
 322 static int tpm_tis_send_data(struct tpm_chip *chip, const u8 *buf, size_t len)
 323 {
 324         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 325         int rc, status, burstcnt;
 326         size_t count = 0;
 327         bool itpm = priv->flags & TPM_TIS_ITPM_WORKAROUND;
 328
 329         status = tpm_tis_status(chip);
 330         if ((status & TPM_STS_COMMAND_READY) == 0) {
 331                 tpm_tis_ready(chip);
 332                 if (wait_for_tpm_stat
 333                     (chip, TPM_STS_COMMAND_READY, chip->timeout_b,
 334                      &priv->int_queue, false) < 0) {
 335                         rc = -ETIME;
 336                         goto out_err;
 337                 }
 338         }
 339
 340         while (count < len - 1) {
 341                 burstcnt = get_burstcount(chip);
 342                 if (burstcnt < 0) {
 343                         dev_err(&chip->dev, "Unable to read burstcount\n");
 344                         rc = burstcnt;
 345                         goto out_err;
 346                 }
 347                 burstcnt = min_t(int, burstcnt, len - count - 1);
 348                 rc = tpm_tis_write_bytes(priv, TPM_DATA_FIFO(priv->locality),
 349                                          burstcnt, buf + count);
 350                 if (rc < 0)
 351                         goto out_err;
 352
 353                 count += burstcnt;
 354
 355                 if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
 356                                         &priv->int_queue, false) < 0) {
 357                         rc = -ETIME;
 358                         goto out_err;
 359                 }
 360                 status = tpm_tis_status(chip);
 361                 if (!itpm && (status & TPM_STS_DATA_EXPECT) == 0) {
 362                         rc = -EIO;
 363                         goto out_err;
 364                 }
 365         }
 366
 367         /* write last byte */
 368         rc = tpm_tis_write8(priv, TPM_DATA_FIFO(priv->locality), buf[count]);
 369         if (rc < 0)
 370                 goto out_err;
 371
 372         if (wait_for_tpm_stat(chip, TPM_STS_VALID, chip->timeout_c,
 373                                 &priv->int_queue, false) < 0) {
 374                 rc = -ETIME;
 375                 goto out_err;
 376         }
 377         status = tpm_tis_status(chip);
 378         if (!itpm && (status & TPM_STS_DATA_EXPECT) != 0) {
 379                 rc = -EIO;
 380                 goto out_err;
 381         }
 382
 383         return 0;
 384
 385 out_err:
 386         tpm_tis_ready(chip);
 387         return rc;
 388 }
 389
 390 static void disable_interrupts(struct tpm_chip *chip)
 391 {
 392         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 393         u32 intmask;
 394         int rc;
 395
 396         if (priv->irq == 0)
 397                 return;
 398
 399         rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
 400         if (rc < 0)
 401                 intmask = 0;
 402
 403         intmask &= ~TPM_GLOBAL_INT_ENABLE;
 404         rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
 405
 406         devm_free_irq(chip->dev.parent, priv->irq, chip);
 407         priv->irq = 0;
 408         chip->flags &= ~TPM_CHIP_FLAG_IRQ;
 409 }
 410
 411 /*
 412  * If interrupts are used (signaled by an irq set in the vendor structure)
 413  * tpm.c can skip polling for the data to be available as the interrupt is
 414  * waited for here
 415  */
 416 static int tpm_tis_send_main(struct tpm_chip *chip, const u8 *buf, size_t len)
 417 {
 418         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 419         int rc;
 420         u32 ordinal;
 421         unsigned long dur;
 422
 423         rc = tpm_tis_send_data(chip, buf, len);
 424         if (rc < 0)
 425                 return rc;
 426
 427         /* go and do it */
 428         rc = tpm_tis_write8(priv, TPM_STS(priv->locality), TPM_STS_GO);
 429         if (rc < 0)
 430                 goto out_err;
 431
 432         if (chip->flags & TPM_CHIP_FLAG_IRQ) {
 433                 ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
 434
 435                 if (chip->flags & TPM_CHIP_FLAG_TPM2)
 436                         dur = tpm2_calc_ordinal_duration(chip, ordinal);
 437                 else
 438                         dur = tpm_calc_ordinal_duration(chip, ordinal);
 439
 440                 if (wait_for_tpm_stat
 441                     (chip, TPM_STS_DATA_AVAIL | TPM_STS_VALID, dur,
 442                      &priv->read_queue, false) < 0) {
 443                         rc = -ETIME;
 444                         goto out_err;
 445                 }
 446         }
 447         return 0;
 448 out_err:
 449         tpm_tis_ready(chip);
 450         return rc;
 451 }
 452
 453 static int tpm_tis_send(struct tpm_chip *chip, u8 *buf, size_t len)
 454 {
 455         int rc, irq;
 456         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 457
 458         if (!(chip->flags & TPM_CHIP_FLAG_IRQ) || priv->irq_tested)
 459                 return tpm_tis_send_main(chip, buf, len);
 460
 461         /* Verify receipt of the expected IRQ */
 462         irq = priv->irq;
 463         priv->irq = 0;
 464         chip->flags &= ~TPM_CHIP_FLAG_IRQ;
 465         rc = tpm_tis_send_main(chip, buf, len);
 466         priv->irq = irq;
 467         chip->flags |= TPM_CHIP_FLAG_IRQ;
 468         if (!priv->irq_tested)
 469                 tpm_msleep(1);
 470         if (!priv->irq_tested)
 471                 disable_interrupts(chip);
 472         priv->irq_tested = true;
 473         return rc;
 474 }
 475
 476 struct tis_vendor_timeout_override {
 477         u32 did_vid;
 478         unsigned long timeout_us[4];
 479 };
 480
 481 static const struct tis_vendor_timeout_override vendor_timeout_overrides[] = {
 482         /* Atmel 3204 */
 483         { 0x32041114, { (TIS_SHORT_TIMEOUT*1000), (TIS_LONG_TIMEOUT*1000),
 484                         (TIS_SHORT_TIMEOUT*1000), (TIS_SHORT_TIMEOUT*1000) } },
 485 };
 486
 487 static bool tpm_tis_update_timeouts(struct tpm_chip *chip,
 488                                     unsigned long *timeout_cap)
 489 {
 490         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 491         int i, rc;
 492         u32 did_vid;
 493
 494         if (chip->ops->clk_enable != NULL)
 495                 chip->ops->clk_enable(chip, true);
 496
 497         rc = tpm_tis_read32(priv, TPM_DID_VID(0), &did_vid);
 498         if (rc < 0)
 499                 goto out;
 500
 501         for (i = 0; i != ARRAY_SIZE(vendor_timeout_overrides); i++) {
 502                 if (vendor_timeout_overrides[i].did_vid != did_vid)
 503                         continue;
 504                 memcpy(timeout_cap, vendor_timeout_overrides[i].timeout_us,
 505                        sizeof(vendor_timeout_overrides[i].timeout_us));
 506                 rc = true;
 507         }
 508
 509         rc = false;
 510
 511 out:
 512         if (chip->ops->clk_enable != NULL)
 513                 chip->ops->clk_enable(chip, false);
 514
 515         return rc;
 516 }
 517
 518 /*
 519  * Early probing for iTPM with STS_DATA_EXPECT flaw.
 520  * Try sending command without itpm flag set and if that
 521  * fails, repeat with itpm flag set.
 522  */
 523 static int probe_itpm(struct tpm_chip *chip)
 524 {
 525         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 526         int rc = 0;
 527         static const u8 cmd_getticks[] = {
 528                 0x00, 0xc1, 0x00, 0x00, 0x00, 0x0a,
 529                 0x00, 0x00, 0x00, 0xf1
 530         };
 531         size_t len = sizeof(cmd_getticks);
 532         u16 vendor;
 533
 534         if (priv->flags & TPM_TIS_ITPM_WORKAROUND)
 535                 return 0;
 536
 537         rc = tpm_tis_read16(priv, TPM_DID_VID(0), &vendor);
 538         if (rc < 0)
 539                 return rc;
 540
 541         /* probe only iTPMS */
 542         if (vendor != TPM_VID_INTEL)
 543                 return 0;
 544
 545         if (request_locality(chip, 0) != 0)
 546                 return -EBUSY;
 547
 548         rc = tpm_tis_send_data(chip, cmd_getticks, len);
 549         if (rc == 0)
 550                 goto out;
 551
 552         tpm_tis_ready(chip);
 553
 554         priv->flags |= TPM_TIS_ITPM_WORKAROUND;
 555
 556         rc = tpm_tis_send_data(chip, cmd_getticks, len);
 557         if (rc == 0)
 558                 dev_info(&chip->dev, "Detected an iTPM.\n");
 559         else {
 560                 priv->flags &= ~TPM_TIS_ITPM_WORKAROUND;
 561                 rc = -EFAULT;
 562         }
 563
 564 out:
 565         tpm_tis_ready(chip);
 566         release_locality(chip, priv->locality);
 567
 568         return rc;
 569 }
 570
 571 static bool tpm_tis_req_canceled(struct tpm_chip *chip, u8 status)
 572 {
 573         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 574
 575         switch (priv->manufacturer_id) {
 576         case TPM_VID_WINBOND:
 577                 return ((status == TPM_STS_VALID) ||
 578                         (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY)));
 579         case TPM_VID_STM:
 580                 return (status == (TPM_STS_VALID | TPM_STS_COMMAND_READY));
 581         default:
 582                 return (status == TPM_STS_COMMAND_READY);
 583         }
 584 }
 585
 586 static irqreturn_t tis_int_handler(int dummy, void *dev_id)
 587 {
 588         struct tpm_chip *chip = dev_id;
 589         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 590         u32 interrupt;
 591         int i, rc;
 592
 593         rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
 594         if (rc < 0)
 595                 return IRQ_NONE;
 596
 597         if (interrupt == 0)
 598                 return IRQ_NONE;
 599
 600         priv->irq_tested = true;
 601         if (interrupt & TPM_INTF_DATA_AVAIL_INT)
 602                 wake_up_interruptible(&priv->read_queue);
 603         if (interrupt & TPM_INTF_LOCALITY_CHANGE_INT)
 604                 for (i = 0; i < 5; i++)
 605                         if (check_locality(chip, i))
 606                                 break;
 607         if (interrupt &
 608             (TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_STS_VALID_INT |
 609              TPM_INTF_CMD_READY_INT))
 610                 wake_up_interruptible(&priv->int_queue);
 611
 612         /* Clear interrupts handled with TPM_EOI */
 613         rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), interrupt);
 614         if (rc < 0)
 615                 return IRQ_NONE;
 616
 617         tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &interrupt);
 618         return IRQ_HANDLED;
 619 }
 620
 621 static int tpm_tis_gen_interrupt(struct tpm_chip *chip)
 622 {
 623         const char *desc = "attempting to generate an interrupt";
 624         u32 cap2;
 625         cap_t cap;
 626
 627         if (chip->flags & TPM_CHIP_FLAG_TPM2)
 628                 return tpm2_get_tpm_pt(chip, 0x100, &cap2, desc);
 629         else
 630                 return tpm_getcap(chip, TPM_CAP_PROP_TIS_TIMEOUT, &cap, desc,
 631                                   0);
 632 }
 633
 634 /* Register the IRQ and issue a command that will cause an interrupt. If an
 635  * irq is seen then leave the chip setup for IRQ operation, otherwise reverse
 636  * everything and leave in polling mode. Returns 0 on success.
 637  */
 638 static int tpm_tis_probe_irq_single(struct tpm_chip *chip, u32 intmask,
 639                                     int flags, int irq)
 640 {
 641         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 642         u8 original_int_vec;
 643         int rc;
 644         u32 int_status;
 645
 646         if (devm_request_irq(chip->dev.parent, irq, tis_int_handler, flags,
 647                              dev_name(&chip->dev), chip) != 0) {
 648                 dev_info(&chip->dev, "Unable to request irq: %d for probe\n",
 649                          irq);
 650                 return -1;
 651         }
 652         priv->irq = irq;
 653
 654         rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
 655                            &original_int_vec);
 656         if (rc < 0)
 657                 return rc;
 658
 659         rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), irq);
 660         if (rc < 0)
 661                 return rc;
 662
 663         rc = tpm_tis_read32(priv, TPM_INT_STATUS(priv->locality), &int_status);
 664         if (rc < 0)
 665                 return rc;
 666
 667         /* Clear all existing */
 668         rc = tpm_tis_write32(priv, TPM_INT_STATUS(priv->locality), int_status);
 669         if (rc < 0)
 670                 return rc;
 671
 672         /* Turn on */
 673         rc = tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality),
 674                              intmask | TPM_GLOBAL_INT_ENABLE);
 675         if (rc < 0)
 676                 return rc;
 677
 678         priv->irq_tested = false;
 679
 680         /* Generate an interrupt by having the core call through to
 681          * tpm_tis_send
 682          */
 683         rc = tpm_tis_gen_interrupt(chip);
 684         if (rc < 0)
 685                 return rc;
 686
 687         /* tpm_tis_send will either confirm the interrupt is working or it
 688          * will call disable_irq which undoes all of the above.
 689          */
 690         if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
 691                 rc = tpm_tis_write8(priv, original_int_vec,
 692                                 TPM_INT_VECTOR(priv->locality));
 693                 if (rc < 0)
 694                         return rc;
 695
 696                 return 1;
 697         }
 698
 699         return 0;
 700 }
 701
 702 /* Try to find the IRQ the TPM is using. This is for legacy x86 systems that
 703  * do not have ACPI/etc. We typically expect the interrupt to be declared if
 704  * present.
 705  */
 706 static void tpm_tis_probe_irq(struct tpm_chip *chip, u32 intmask)
 707 {
 708         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 709         u8 original_int_vec;
 710         int i, rc;
 711
 712         rc = tpm_tis_read8(priv, TPM_INT_VECTOR(priv->locality),
 713                            &original_int_vec);
 714         if (rc < 0)
 715                 return;
 716
 717         if (!original_int_vec) {
 718                 if (IS_ENABLED(CONFIG_X86))
 719                         for (i = 3; i <= 15; i++)
 720                                 if (!tpm_tis_probe_irq_single(chip, intmask, 0,
 721                                                               i))
 722                                         return;
 723         } else if (!tpm_tis_probe_irq_single(chip, intmask, 0,
 724                                              original_int_vec))
 725                 return;
 726 }
 727
 728 void tpm_tis_remove(struct tpm_chip *chip)
 729 {
 730         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 731         u32 reg = TPM_INT_ENABLE(priv->locality);
 732         u32 interrupt;
 733         int rc;
 734
 735         tpm_tis_clkrun_enable(chip, true);
 736
 737         rc = tpm_tis_read32(priv, reg, &interrupt);
 738         if (rc < 0)
 739                 interrupt = 0;
 740
 741         tpm_tis_write32(priv, reg, ~TPM_GLOBAL_INT_ENABLE & interrupt);
 742
 743         tpm_tis_clkrun_enable(chip, false);
 744
 745         if (priv->ilb_base_addr)
 746                 iounmap(priv->ilb_base_addr);
 747 }
 748 EXPORT_SYMBOL_GPL(tpm_tis_remove);
 749
 750 /**
 751  * tpm_tis_clkrun_enable() - Keep clkrun protocol disabled for entire duration
 752  *                           of a single TPM command
 753  * @chip:       TPM chip to use
 754  * @value:      1 - Disable CLKRUN protocol, so that clocks are free running
 755  *              0 - Enable CLKRUN protocol
 756  * Call this function directly in tpm_tis_remove() in error or driver removal
 757  * path, since the chip->ops is set to NULL in tpm_chip_unregister().
 758  */
 759 static void tpm_tis_clkrun_enable(struct tpm_chip *chip, bool value)
 760 {
 761         struct tpm_tis_data *data = dev_get_drvdata(&chip->dev);
 762         u32 clkrun_val;
 763
 764         if (!IS_ENABLED(CONFIG_X86) || !is_bsw() ||
 765             !data->ilb_base_addr)
 766                 return;
 767
 768         if (value) {
 769                 data->clkrun_enabled++;
 770                 if (data->clkrun_enabled > 1)
 771                         return;
 772                 clkrun_val = ioread32(data->ilb_base_addr + LPC_CNTRL_OFFSET);
 773
 774                 /* Disable LPC CLKRUN# */
 775                 clkrun_val &= ~LPC_CLKRUN_EN;
 776                 iowrite32(clkrun_val, data->ilb_base_addr + LPC_CNTRL_OFFSET);
 777
 778                 /*
 779                  * Write any random value on port 0x80 which is on LPC, to make
 780                  * sure LPC clock is running before sending any TPM command.
 781                  */
 782                 outb(0xCC, 0x80);
 783         } else {
 784                 data->clkrun_enabled--;
 785                 if (data->clkrun_enabled)
 786                         return;
 787
 788                 clkrun_val = ioread32(data->ilb_base_addr + LPC_CNTRL_OFFSET);
 789
 790                 /* Enable LPC CLKRUN# */
 791                 clkrun_val |= LPC_CLKRUN_EN;
 792                 iowrite32(clkrun_val, data->ilb_base_addr + LPC_CNTRL_OFFSET);
 793
 794                 /*
 795                  * Write any random value on port 0x80 which is on LPC, to make
 796                  * sure LPC clock is running before sending any TPM command.
 797                  */
 798                 outb(0xCC, 0x80);
 799         }
 800 }
 801
 802 static const struct tpm_class_ops tpm_tis = {
 803         .flags = TPM_OPS_AUTO_STARTUP,
 804         .status = tpm_tis_status,
 805         .recv = tpm_tis_recv,
 806         .send = tpm_tis_send,
 807         .cancel = tpm_tis_ready,
 808         .update_timeouts = tpm_tis_update_timeouts,
 809         .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 810         .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID,
 811         .req_canceled = tpm_tis_req_canceled,
 812         .request_locality = request_locality,
 813         .relinquish_locality = release_locality,
 814         .clk_enable = tpm_tis_clkrun_enable,
 815 };
 816
 817 int tpm_tis_core_init(struct device *dev, struct tpm_tis_data *priv, int irq,
 818                       const struct tpm_tis_phy_ops *phy_ops,
 819                       acpi_handle acpi_dev_handle)
 820 {
 821         u32 vendor;
 822         u32 intfcaps;
 823         u32 intmask;
 824         u32 clkrun_val;
 825         u8 rid;
 826         int rc, probe;
 827         struct tpm_chip *chip;
 828
 829         chip = tpmm_chip_alloc(dev, &tpm_tis);
 830         if (IS_ERR(chip))
 831                 return PTR_ERR(chip);
 832
 833 #ifdef CONFIG_ACPI
 834         chip->acpi_dev_handle = acpi_dev_handle;
 835 #endif
 836
 837         chip->hwrng.quality = priv->rng_quality;
 838
 839         /* Maximum timeouts */
 840         chip->timeout_a = msecs_to_jiffies(TIS_TIMEOUT_A_MAX);
 841         chip->timeout_b = msecs_to_jiffies(TIS_TIMEOUT_B_MAX);
 842         chip->timeout_c = msecs_to_jiffies(TIS_TIMEOUT_C_MAX);
 843         chip->timeout_d = msecs_to_jiffies(TIS_TIMEOUT_D_MAX);
 844         priv->phy_ops = phy_ops;
 845         dev_set_drvdata(&chip->dev, priv);
 846
 847         if (is_bsw()) {
 848                 priv->ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR,
 849                                         ILB_REMAP_SIZE);
 850                 if (!priv->ilb_base_addr)
 851                         return -ENOMEM;
 852
 853                 clkrun_val = ioread32(priv->ilb_base_addr + LPC_CNTRL_OFFSET);
 854                 /* Check if CLKRUN# is already not enabled in the LPC bus */
 855                 if (!(clkrun_val & LPC_CLKRUN_EN)) {
 856                         iounmap(priv->ilb_base_addr);
 857                         priv->ilb_base_addr = NULL;
 858                 }
 859         }
 860
 861         if (chip->ops->clk_enable != NULL)
 862                 chip->ops->clk_enable(chip, true);
 863
 864         if (wait_startup(chip, 0) != 0) {
 865                 rc = -ENODEV;
 866                 goto out_err;
 867         }
 868
 869         /* Take control of the TPM's interrupt hardware and shut it off */
 870         rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
 871         if (rc < 0)
 872                 goto out_err;
 873
 874         intmask |= TPM_INTF_CMD_READY_INT | TPM_INTF_LOCALITY_CHANGE_INT |
 875                    TPM_INTF_DATA_AVAIL_INT | TPM_INTF_STS_VALID_INT;
 876         intmask &= ~TPM_GLOBAL_INT_ENABLE;
 877
 878         rc = request_locality(chip, 0);
 879         if (rc < 0) {
 880                 rc = -ENODEV;
 881                 goto out_err;
 882         }
 883
 884         tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
 885         release_locality(chip, 0);
 886
 887         rc = tpm2_probe(chip);
 888         if (rc)
 889                 goto out_err;
 890
 891         rc = tpm_tis_read32(priv, TPM_DID_VID(0), &vendor);
 892         if (rc < 0)
 893                 goto out_err;
 894
 895         priv->manufacturer_id = vendor;
 896
 897         rc = tpm_tis_read8(priv, TPM_RID(0), &rid);
 898         if (rc < 0)
 899                 goto out_err;
 900
 901         dev_info(dev, "%s TPM (device-id 0x%X, rev-id %d)\n",
 902                  (chip->flags & TPM_CHIP_FLAG_TPM2) ? "2.0" : "1.2",
 903                  vendor >> 16, rid);
 904
 905         probe = probe_itpm(chip);
 906         if (probe < 0) {
 907                 rc = -ENODEV;
 908                 goto out_err;
 909         }
 910
 911         /* Figure out the capabilities */
 912         rc = tpm_tis_read32(priv, TPM_INTF_CAPS(priv->locality), &intfcaps);
 913         if (rc < 0)
 914                 goto out_err;
 915
 916         dev_dbg(dev, "TPM interface capabilities (0x%x):\n",
 917                 intfcaps);
 918         if (intfcaps & TPM_INTF_BURST_COUNT_STATIC)
 919                 dev_dbg(dev, "\tBurst Count Static\n");
 920         if (intfcaps & TPM_INTF_CMD_READY_INT)
 921                 dev_dbg(dev, "\tCommand Ready Int Support\n");
 922         if (intfcaps & TPM_INTF_INT_EDGE_FALLING)
 923                 dev_dbg(dev, "\tInterrupt Edge Falling\n");
 924         if (intfcaps & TPM_INTF_INT_EDGE_RISING)
 925                 dev_dbg(dev, "\tInterrupt Edge Rising\n");
 926         if (intfcaps & TPM_INTF_INT_LEVEL_LOW)
 927                 dev_dbg(dev, "\tInterrupt Level Low\n");
 928         if (intfcaps & TPM_INTF_INT_LEVEL_HIGH)
 929                 dev_dbg(dev, "\tInterrupt Level High\n");
 930         if (intfcaps & TPM_INTF_LOCALITY_CHANGE_INT)
 931                 dev_dbg(dev, "\tLocality Change Int Support\n");
 932         if (intfcaps & TPM_INTF_STS_VALID_INT)
 933                 dev_dbg(dev, "\tSts Valid Int Support\n");
 934         if (intfcaps & TPM_INTF_DATA_AVAIL_INT)
 935                 dev_dbg(dev, "\tData Avail Int Support\n");
 936
 937         /* INTERRUPT Setup */
 938         init_waitqueue_head(&priv->read_queue);
 939         init_waitqueue_head(&priv->int_queue);
 940         if (irq != -1) {
 941                 /* Before doing irq testing issue a command to the TPM in polling mode
 942                  * to make sure it works. May as well use that command to set the
 943                  * proper timeouts for the driver.
 944                  */
 945                 if (tpm_get_timeouts(chip)) {
 946                         dev_err(dev, "Could not get TPM timeouts and durations\n");
 947                         rc = -ENODEV;
 948                         goto out_err;
 949                 }
 950
 951                 if (irq) {
 952                         tpm_tis_probe_irq_single(chip, intmask, IRQF_SHARED,
 953                                                  irq);
 954                         if (!(chip->flags & TPM_CHIP_FLAG_IRQ)) {
 955                                 dev_err(&chip->dev, FW_BUG
 956                                         "TPM interrupt not working, polling instead\n");
 957
 958                                 disable_interrupts(chip);
 959                         }
 960                 } else {
 961                         tpm_tis_probe_irq(chip, intmask);
 962                 }
 963         }
 964
 965         rc = tpm_chip_register(chip);
 966         if (rc)
 967                 goto out_err;
 968
 969         if (chip->ops->clk_enable != NULL)
 970                 chip->ops->clk_enable(chip, false);
 971
 972         return 0;
 973 out_err:
 974         if (chip->ops->clk_enable != NULL)
 975                 chip->ops->clk_enable(chip, false);
 976
 977         tpm_tis_remove(chip);
 978
 979         return rc;
 980 }
 981 EXPORT_SYMBOL_GPL(tpm_tis_core_init);
 982
 983 #ifdef CONFIG_PM_SLEEP
 984 static void tpm_tis_reenable_interrupts(struct tpm_chip *chip)
 985 {
 986         struct tpm_tis_data *priv = dev_get_drvdata(&chip->dev);
 987         u32 intmask;
 988         int rc;
 989
 990         if (chip->ops->clk_enable != NULL)
 991                 chip->ops->clk_enable(chip, true);
 992
 993         /* reenable interrupts that device may have lost or
 994          * BIOS/firmware may have disabled
 995          */
 996         rc = tpm_tis_write8(priv, TPM_INT_VECTOR(priv->locality), priv->irq);
 997         if (rc < 0)
 998                 goto out;
 999
1000         rc = tpm_tis_read32(priv, TPM_INT_ENABLE(priv->locality), &intmask);
1001         if (rc < 0)
1002                 goto out;
1003
1004         intmask |= TPM_INTF_CMD_READY_INT
1005             | TPM_INTF_LOCALITY_CHANGE_INT | TPM_INTF_DATA_AVAIL_INT
1006             | TPM_INTF_STS_VALID_INT | TPM_GLOBAL_INT_ENABLE;
1007
1008         tpm_tis_write32(priv, TPM_INT_ENABLE(priv->locality), intmask);
1009
1010 out:
1011         if (chip->ops->clk_enable != NULL)
1012                 chip->ops->clk_enable(chip, false);
1013
1014         return;
1015 }
1016
1017 int tpm_tis_resume(struct device *dev)
1018 {
1019         struct tpm_chip *chip = dev_get_drvdata(dev);
1020         int ret;
1021
1022         if (chip->flags & TPM_CHIP_FLAG_IRQ)
1023                 tpm_tis_reenable_interrupts(chip);
1024
1025         ret = tpm_pm_resume(dev);
1026         if (ret)
1027                 return ret;
1028
1029         /* TPM 1.2 requires self-test on resume. This function actually returns
1030          * an error code but for unknown reason it isn't handled.
1031          */
1032         if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
1033                 tpm_do_selftest(chip);
1034
1035         return 0;
1036 }
1037 EXPORT_SYMBOL_GPL(tpm_tis_resume);
1038 #endif
1039
1040 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
1041 MODULE_DESCRIPTION("TPM Driver");
1042 MODULE_VERSION("2.0");
1043 MODULE_LICENSE("GPL");