drivers/char/tpm/tpm_tis

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

DEFINITIONS
