drivers/char/tpm/tpm_tis.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 <linux/of.h>
  32 #include <linux/of_device.h>
  33 #include "tpm.h"
  34 #include "tpm_tis_core.h"
  35
  36 struct tpm_info {
  37         struct resource res;
  38         /* irq > 0 means: use irq $irq;
  39          * irq = 0 means: autoprobe for an irq;
  40          * irq = -1 means: no irq support
  41          */
  42         int irq;
  43 };
  44
  45 struct tpm_tis_tcg_phy {
  46         struct tpm_tis_data priv;
  47         void __iomem *iobase;
  48 };
  49
  50 static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data)
  51 {
  52         return container_of(data, struct tpm_tis_tcg_phy, priv);
  53 }
  54
  55 static bool interrupts = true;
  56 module_param(interrupts, bool, 0444);
  57 MODULE_PARM_DESC(interrupts, "Enable interrupts");
  58
  59 static bool itpm;
  60 module_param(itpm, bool, 0444);
  61 MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
  62
  63 static bool force;
  64 #ifdef CONFIG_X86
  65 module_param(force, bool, 0444);
  66 MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
  67 #endif
  68
  69 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
  70 static int has_hid(struct acpi_device *dev, const char *hid)
  71 {
  72         struct acpi_hardware_id *id;
  73
  74         list_for_each_entry(id, &dev->pnp.ids, list)
  75                 if (!strcmp(hid, id->id))
  76                         return 1;
  77
  78         return 0;
  79 }
  80
  81 static inline int is_itpm(struct acpi_device *dev)
  82 {
  83         if (!dev)
  84                 return 0;
  85         return has_hid(dev, "INTC0102");
  86 }
  87 #else
  88 static inline int is_itpm(struct acpi_device *dev)
  89 {
  90         return 0;
  91 }
  92 #endif
  93
  94 #if defined(CONFIG_ACPI)
  95 #define DEVICE_IS_TPM2 1
  96
  97 static const struct acpi_device_id tpm_acpi_tbl[] = {
  98         {"MSFT0101", DEVICE_IS_TPM2},
  99         {},
 100 };
 101 MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);
 102
 103 static int check_acpi_tpm2(struct device *dev)
 104 {
 105         const struct acpi_device_id *aid = acpi_match_device(tpm_acpi_tbl, dev);
 106         struct acpi_table_tpm2 *tbl;
 107         acpi_status st;
 108
 109         if (!aid || aid->driver_data != DEVICE_IS_TPM2)
 110                 return 0;
 111
 112         /* If the ACPI TPM2 signature is matched then a global ACPI_SIG_TPM2
 113          * table is mandatory
 114          */
 115         st =
 116             acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl);
 117         if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) {
 118                 dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n");
 119                 return -EINVAL;
 120         }
 121
 122         /* The tpm2_crb driver handles this device */
 123         if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
 124                 return -ENODEV;
 125
 126         return 0;
 127 }
 128 #else
 129 static int check_acpi_tpm2(struct device *dev)
 130 {
 131         return 0;
 132 }
 133 #endif
 134
 135 #ifdef CONFIG_X86
 136 #define INTEL_LEGACY_BLK_BASE_ADDR      0xFED08000
 137 #define ILB_REMAP_SIZE                  0x100
 138 #define LPC_CNTRL_REG_OFFSET            0x84
 139 #define LPC_CLKRUN_EN                   (1 << 2)
 140
 141 static void __iomem *ilb_base_addr;
 142
 143 static inline bool is_bsw(void)
 144 {
 145         return ((boot_cpu_data.x86_model == INTEL_FAM6_ATOM_AIRMONT) ? 1 : 0);
 146 }
 147
 148 /**
 149  * tpm_platform_begin_xfer() - clear LPC CLKRUN_EN i.e. clocks will be running
 150  */
 151 static void tpm_platform_begin_xfer(void)
 152 {
 153         u32 clkrun_val;
 154
 155         if (!is_bsw())
 156                 return;
 157
 158         clkrun_val = ioread32(ilb_base_addr + LPC_CNTRL_REG_OFFSET);
 159
 160         /* Disable LPC CLKRUN# */
 161         clkrun_val &= ~LPC_CLKRUN_EN;
 162         iowrite32(clkrun_val, ilb_base_addr + LPC_CNTRL_REG_OFFSET);
 163
 164         /*
 165          * Write any random value on port 0x80 which is on LPC, to make
 166          * sure LPC clock is running before sending any TPM command.
 167          */
 168         outb(0xCC, 0x80);
 169
 170 }
 171
 172 /**
 173  * tpm_platform_end_xfer() - set LPC CLKRUN_EN i.e. clocks can be turned off
 174  */
 175 static void tpm_platform_end_xfer(void)
 176 {
 177         u32 clkrun_val;
 178
 179         if (!is_bsw())
 180                 return;
 181
 182         clkrun_val = ioread32(ilb_base_addr + LPC_CNTRL_REG_OFFSET);
 183
 184         /* Enable LPC CLKRUN# */
 185         clkrun_val |= LPC_CLKRUN_EN;
 186         iowrite32(clkrun_val, ilb_base_addr + LPC_CNTRL_REG_OFFSET);
 187
 188         /*
 189          * Write any random value on port 0x80 which is on LPC, to make
 190          * sure LPC clock is running before sending any TPM command.
 191          */
 192         outb(0xCC, 0x80);
 193
 194 }
 195 #else
 196 static inline bool is_bsw(void)
 197 {
 198         return false;
 199 }
 200
 201 static void tpm_platform_begin_xfer(void)
 202 {
 203 }
 204
 205 static void tpm_platform_end_xfer(void)
 206 {
 207 }
 208 #endif
 209
 210 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 211                               u8 *result)
 212 {
 213         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 214
 215         tpm_platform_begin_xfer();
 216
 217         while (len--)
 218                 *result++ = ioread8(phy->iobase + addr);
 219
 220         tpm_platform_end_xfer();
 221
 222         return 0;
 223 }
 224
 225 static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 226                                u8 *value)
 227 {
 228         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 229
 230         tpm_platform_begin_xfer();
 231
 232         while (len--)
 233                 iowrite8(*value++, phy->iobase + addr);
 234
 235         tpm_platform_end_xfer();
 236
 237         return 0;
 238 }
 239
 240 static int tpm_tcg_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
 241 {
 242         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 243
 244         tpm_platform_begin_xfer();
 245
 246         *result = ioread16(phy->iobase + addr);
 247
 248         tpm_platform_end_xfer();
 249
 250         return 0;
 251 }
 252
 253 static int tpm_tcg_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
 254 {
 255         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 256
 257         tpm_platform_begin_xfer();
 258
 259         *result = ioread32(phy->iobase + addr);
 260
 261         tpm_platform_end_xfer();
 262
 263         return 0;
 264 }
 265
 266 static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
 267 {
 268         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 269
 270         tpm_platform_begin_xfer();
 271
 272         iowrite32(value, phy->iobase + addr);
 273
 274         tpm_platform_end_xfer();
 275
 276         return 0;
 277 }
 278
 279 static const struct tpm_tis_phy_ops tpm_tcg = {
 280         .read_bytes = tpm_tcg_read_bytes,
 281         .write_bytes = tpm_tcg_write_bytes,
 282         .read16 = tpm_tcg_read16,
 283         .read32 = tpm_tcg_read32,
 284         .write32 = tpm_tcg_write32,
 285 };
 286
 287 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info)
 288 {
 289         struct tpm_tis_tcg_phy *phy;
 290         int irq = -1;
 291         int rc;
 292
 293         rc = check_acpi_tpm2(dev);
 294         if (rc)
 295                 return rc;
 296
 297         phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
 298         if (phy == NULL)
 299                 return -ENOMEM;
 300
 301         phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
 302         if (IS_ERR(phy->iobase))
 303                 return PTR_ERR(phy->iobase);
 304
 305         if (interrupts)
 306                 irq = tpm_info->irq;
 307
 308         if (itpm || is_itpm(ACPI_COMPANION(dev)))
 309                 phy->priv.flags |= TPM_TIS_ITPM_WORKAROUND;
 310
 311         return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
 312                                  ACPI_HANDLE(dev));
 313 }
 314
 315 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
 316
 317 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
 318                             const struct pnp_device_id *pnp_id)
 319 {
 320         struct tpm_info tpm_info = {};
 321         struct resource *res;
 322
 323         res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0);
 324         if (!res)
 325                 return -ENODEV;
 326         tpm_info.res = *res;
 327
 328         if (pnp_irq_valid(pnp_dev, 0))
 329                 tpm_info.irq = pnp_irq(pnp_dev, 0);
 330         else
 331                 tpm_info.irq = -1;
 332
 333         return tpm_tis_init(&pnp_dev->dev, &tpm_info);
 334 }
 335
 336 static struct pnp_device_id tpm_pnp_tbl[] = {
 337         {"PNP0C31", 0},         /* TPM */
 338         {"ATM1200", 0},         /* Atmel */
 339         {"IFX0102", 0},         /* Infineon */
 340         {"BCM0101", 0},         /* Broadcom */
 341         {"BCM0102", 0},         /* Broadcom */
 342         {"NSC1200", 0},         /* National */
 343         {"ICO0102", 0},         /* Intel */
 344         /* Add new here */
 345         {"", 0},                /* User Specified */
 346         {"", 0}                 /* Terminator */
 347 };
 348 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
 349
 350 static void tpm_tis_pnp_remove(struct pnp_dev *dev)
 351 {
 352         struct tpm_chip *chip = pnp_get_drvdata(dev);
 353
 354         tpm_chip_unregister(chip);
 355         tpm_tis_remove(chip);
 356 }
 357
 358 static struct pnp_driver tis_pnp_driver = {
 359         .name = "tpm_tis",
 360         .id_table = tpm_pnp_tbl,
 361         .probe = tpm_tis_pnp_init,
 362         .remove = tpm_tis_pnp_remove,
 363         .driver = {
 364                 .pm = &tpm_tis_pm,
 365         },
 366 };
 367
 368 #define TIS_HID_USR_IDX sizeof(tpm_pnp_tbl)/sizeof(struct pnp_device_id) -2
 369 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
 370                     sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
 371 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
 372
 373 static struct platform_device *force_pdev;
 374
 375 static int tpm_tis_plat_probe(struct platform_device *pdev)
 376 {
 377         struct tpm_info tpm_info = {};
 378         struct resource *res;
 379
 380         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 381         if (res == NULL) {
 382                 dev_err(&pdev->dev, "no memory resource defined\n");
 383                 return -ENODEV;
 384         }
 385         tpm_info.res = *res;
 386
 387         tpm_info.irq = platform_get_irq(pdev, 0);
 388         if (tpm_info.irq <= 0) {
 389                 if (pdev != force_pdev)
 390                         tpm_info.irq = -1;
 391                 else
 392                         /* When forcing auto probe the IRQ */
 393                         tpm_info.irq = 0;
 394         }
 395
 396         return tpm_tis_init(&pdev->dev, &tpm_info);
 397 }
 398
 399 static int tpm_tis_plat_remove(struct platform_device *pdev)
 400 {
 401         struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
 402
 403         tpm_chip_unregister(chip);
 404         tpm_tis_remove(chip);
 405
 406         return 0;
 407 }
 408
 409 #ifdef CONFIG_OF
 410 static const struct of_device_id tis_of_platform_match[] = {
 411         {.compatible = "tcg,tpm-tis-mmio"},
 412         {},
 413 };
 414 MODULE_DEVICE_TABLE(of, tis_of_platform_match);
 415 #endif
 416
 417 static struct platform_driver tis_drv = {
 418         .probe = tpm_tis_plat_probe,
 419         .remove = tpm_tis_plat_remove,
 420         .driver = {
 421                 .name           = "tpm_tis",
 422                 .pm             = &tpm_tis_pm,
 423                 .of_match_table = of_match_ptr(tis_of_platform_match),
 424                 .acpi_match_table = ACPI_PTR(tpm_acpi_tbl),
 425         },
 426 };
 427
 428 static int tpm_tis_force_device(void)
 429 {
 430         struct platform_device *pdev;
 431         static const struct resource x86_resources[] = {
 432                 {
 433                         .start = 0xFED40000,
 434                         .end = 0xFED40000 + TIS_MEM_LEN - 1,
 435                         .flags = IORESOURCE_MEM,
 436                 },
 437         };
 438
 439         if (!force)
 440                 return 0;
 441
 442         /* The driver core will match the name tpm_tis of the device to
 443          * the tpm_tis platform driver and complete the setup via
 444          * tpm_tis_plat_probe
 445          */
 446         pdev = platform_device_register_simple("tpm_tis", -1, x86_resources,
 447                                                ARRAY_SIZE(x86_resources));
 448         if (IS_ERR(pdev))
 449                 return PTR_ERR(pdev);
 450         force_pdev = pdev;
 451
 452         return 0;
 453 }
 454
 455 static int __init init_tis(void)
 456 {
 457         int rc;
 458
 459         rc = tpm_tis_force_device();
 460         if (rc)
 461                 goto err_force;
 462
 463 #ifdef CONFIG_X86
 464         if (is_bsw())
 465                 ilb_base_addr = ioremap(INTEL_LEGACY_BLK_BASE_ADDR,
 466                                         ILB_REMAP_SIZE);
 467 #endif
 468         rc = platform_driver_register(&tis_drv);
 469         if (rc)
 470                 goto err_platform;
 471
 472
 473         if (IS_ENABLED(CONFIG_PNP)) {
 474                 rc = pnp_register_driver(&tis_pnp_driver);
 475                 if (rc)
 476                         goto err_pnp;
 477         }
 478
 479         return 0;
 480
 481 err_pnp:
 482         platform_driver_unregister(&tis_drv);
 483 err_platform:
 484         if (force_pdev)
 485                 platform_device_unregister(force_pdev);
 486 #ifdef CONFIG_X86
 487         if (is_bsw())
 488                 iounmap(ilb_base_addr);
 489 #endif
 490 err_force:
 491         return rc;
 492 }
 493
 494 static void __exit cleanup_tis(void)
 495 {
 496         pnp_unregister_driver(&tis_pnp_driver);
 497         platform_driver_unregister(&tis_drv);
 498
 499 #ifdef CONFIG_X86
 500         if (is_bsw())
 501                 iounmap(ilb_base_addr);
 502 #endif
 503         if (force_pdev)
 504                 platform_device_unregister(force_pdev);
 505 }
 506
 507 module_init(init_tis);
 508 module_exit(cleanup_tis);
 509 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 510 MODULE_DESCRIPTION("TPM Driver");
 511 MODULE_VERSION("2.0");
 512 MODULE_LICENSE("GPL");