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