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         return has_hid(dev, "INTC0102");
  84 }
  85 #else
  86 static inline int is_itpm(struct acpi_device *dev)
  87 {
  88         return 0;
  89 }
  90 #endif
  91
  92 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
  93                               u8 *result)
  94 {
  95         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
  96
  97         while (len--)
  98                 *result++ = ioread8(phy->iobase + addr);
  99         return 0;
 100 }
 101
 102 static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 103                                u8 *value)
 104 {
 105         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 106
 107         while (len--)
 108                 iowrite8(*value++, phy->iobase + addr);
 109         return 0;
 110 }
 111
 112 static int tpm_tcg_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
 113 {
 114         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 115
 116         *result = ioread16(phy->iobase + addr);
 117         return 0;
 118 }
 119
 120 static int tpm_tcg_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
 121 {
 122         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 123
 124         *result = ioread32(phy->iobase + addr);
 125         return 0;
 126 }
 127
 128 static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
 129 {
 130         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 131
 132         iowrite32(value, phy->iobase + addr);
 133         return 0;
 134 }
 135
 136 static const struct tpm_tis_phy_ops tpm_tcg = {
 137         .read_bytes = tpm_tcg_read_bytes,
 138         .write_bytes = tpm_tcg_write_bytes,
 139         .read16 = tpm_tcg_read16,
 140         .read32 = tpm_tcg_read32,
 141         .write32 = tpm_tcg_write32,
 142 };
 143
 144 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
 145                         acpi_handle acpi_dev_handle)
 146 {
 147         struct tpm_tis_tcg_phy *phy;
 148         int irq = -1;
 149
 150         phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
 151         if (phy == NULL)
 152                 return -ENOMEM;
 153
 154         phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
 155         if (IS_ERR(phy->iobase))
 156                 return PTR_ERR(phy->iobase);
 157
 158         if (interrupts)
 159                 irq = tpm_info->irq;
 160
 161         if (itpm)
 162                 phy->priv.flags |= TPM_TIS_ITPM_POSSIBLE;
 163
 164         return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
 165                                  acpi_dev_handle);
 166 }
 167
 168 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
 169
 170 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
 171                             const struct pnp_device_id *pnp_id)
 172 {
 173         struct tpm_info tpm_info = {};
 174         acpi_handle acpi_dev_handle = NULL;
 175         struct resource *res;
 176
 177         res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0);
 178         if (!res)
 179                 return -ENODEV;
 180         tpm_info.res = *res;
 181
 182         if (pnp_irq_valid(pnp_dev, 0))
 183                 tpm_info.irq = pnp_irq(pnp_dev, 0);
 184         else
 185                 tpm_info.irq = -1;
 186
 187         if (pnp_acpi_device(pnp_dev)) {
 188                 if (is_itpm(pnp_acpi_device(pnp_dev)))
 189                         itpm = true;
 190
 191                 acpi_dev_handle = ACPI_HANDLE(&pnp_dev->dev);
 192         }
 193
 194         return tpm_tis_init(&pnp_dev->dev, &tpm_info, acpi_dev_handle);
 195 }
 196
 197 static struct pnp_device_id tpm_pnp_tbl[] = {
 198         {"PNP0C31", 0},         /* TPM */
 199         {"ATM1200", 0},         /* Atmel */
 200         {"IFX0102", 0},         /* Infineon */
 201         {"BCM0101", 0},         /* Broadcom */
 202         {"BCM0102", 0},         /* Broadcom */
 203         {"NSC1200", 0},         /* National */
 204         {"ICO0102", 0},         /* Intel */
 205         /* Add new here */
 206         {"", 0},                /* User Specified */
 207         {"", 0}                 /* Terminator */
 208 };
 209 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
 210
 211 static void tpm_tis_pnp_remove(struct pnp_dev *dev)
 212 {
 213         struct tpm_chip *chip = pnp_get_drvdata(dev);
 214
 215         tpm_chip_unregister(chip);
 216         tpm_tis_remove(chip);
 217 }
 218
 219 static struct pnp_driver tis_pnp_driver = {
 220         .name = "tpm_tis",
 221         .id_table = tpm_pnp_tbl,
 222         .probe = tpm_tis_pnp_init,
 223         .remove = tpm_tis_pnp_remove,
 224         .driver = {
 225                 .pm = &tpm_tis_pm,
 226         },
 227 };
 228
 229 #define TIS_HID_USR_IDX sizeof(tpm_pnp_tbl)/sizeof(struct pnp_device_id) -2
 230 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
 231                     sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
 232 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
 233
 234 #ifdef CONFIG_ACPI
 235 static int tpm_check_resource(struct acpi_resource *ares, void *data)
 236 {
 237         struct tpm_info *tpm_info = (struct tpm_info *) data;
 238         struct resource res;
 239
 240         if (acpi_dev_resource_interrupt(ares, 0, &res))
 241                 tpm_info->irq = res.start;
 242         else if (acpi_dev_resource_memory(ares, &res)) {
 243                 tpm_info->res = res;
 244                 tpm_info->res.name = NULL;
 245         }
 246
 247         return 1;
 248 }
 249
 250 static int tpm_tis_acpi_init(struct acpi_device *acpi_dev)
 251 {
 252         struct acpi_table_tpm2 *tbl;
 253         acpi_status st;
 254         struct list_head resources;
 255         struct tpm_info tpm_info = {};
 256         int ret;
 257
 258         st = acpi_get_table(ACPI_SIG_TPM2, 1,
 259                             (struct acpi_table_header **) &tbl);
 260         if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) {
 261                 dev_err(&acpi_dev->dev,
 262                         FW_BUG "failed to get TPM2 ACPI table\n");
 263                 return -EINVAL;
 264         }
 265
 266         if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
 267                 return -ENODEV;
 268
 269         INIT_LIST_HEAD(&resources);
 270         tpm_info.irq = -1;
 271         ret = acpi_dev_get_resources(acpi_dev, &resources, tpm_check_resource,
 272                                      &tpm_info);
 273         if (ret < 0)
 274                 return ret;
 275
 276         acpi_dev_free_resource_list(&resources);
 277
 278         if (resource_type(&tpm_info.res) != IORESOURCE_MEM) {
 279                 dev_err(&acpi_dev->dev,
 280                         FW_BUG "TPM2 ACPI table does not define a memory resource\n");
 281                 return -EINVAL;
 282         }
 283
 284         if (is_itpm(acpi_dev))
 285                 itpm = true;
 286
 287         return tpm_tis_init(&acpi_dev->dev, &tpm_info, acpi_dev->handle);
 288 }
 289
 290 static int tpm_tis_acpi_remove(struct acpi_device *dev)
 291 {
 292         struct tpm_chip *chip = dev_get_drvdata(&dev->dev);
 293
 294         tpm_chip_unregister(chip);
 295         tpm_tis_remove(chip);
 296
 297         return 0;
 298 }
 299
 300 static struct acpi_device_id tpm_acpi_tbl[] = {
 301         {"MSFT0101", 0},        /* TPM 2.0 */
 302         /* Add new here */
 303         {"", 0},                /* User Specified */
 304         {"", 0}                 /* Terminator */
 305 };
 306 MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);
 307
 308 static struct acpi_driver tis_acpi_driver = {
 309         .name = "tpm_tis",
 310         .ids = tpm_acpi_tbl,
 311         .ops = {
 312                 .add = tpm_tis_acpi_init,
 313                 .remove = tpm_tis_acpi_remove,
 314         },
 315         .drv = {
 316                 .pm = &tpm_tis_pm,
 317         },
 318 };
 319 #endif
 320
 321 static struct platform_device *force_pdev;
 322
 323 static int tpm_tis_plat_probe(struct platform_device *pdev)
 324 {
 325         struct tpm_info tpm_info = {};
 326         struct resource *res;
 327
 328         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 329         if (res == NULL) {
 330                 dev_err(&pdev->dev, "no memory resource defined\n");
 331                 return -ENODEV;
 332         }
 333         tpm_info.res = *res;
 334
 335         res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
 336         if (res) {
 337                 tpm_info.irq = res->start;
 338         } else {
 339                 if (pdev == force_pdev)
 340                         tpm_info.irq = -1;
 341                 else
 342                         /* When forcing auto probe the IRQ */
 343                         tpm_info.irq = 0;
 344         }
 345
 346         return tpm_tis_init(&pdev->dev, &tpm_info, NULL);
 347 }
 348
 349 static int tpm_tis_plat_remove(struct platform_device *pdev)
 350 {
 351         struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
 352
 353         tpm_chip_unregister(chip);
 354         tpm_tis_remove(chip);
 355
 356         return 0;
 357 }
 358
 359 #ifdef CONFIG_OF
 360 static const struct of_device_id tis_of_platform_match[] = {
 361         {.compatible = "tcg,tpm-tis-mmio"},
 362         {},
 363 };
 364 MODULE_DEVICE_TABLE(of, tis_of_platform_match);
 365 #endif
 366
 367 static struct platform_driver tis_drv = {
 368         .probe = tpm_tis_plat_probe,
 369         .remove = tpm_tis_plat_remove,
 370         .driver = {
 371                 .name           = "tpm_tis",
 372                 .pm             = &tpm_tis_pm,
 373                 .of_match_table = of_match_ptr(tis_of_platform_match),
 374         },
 375 };
 376
 377 static int tpm_tis_force_device(void)
 378 {
 379         struct platform_device *pdev;
 380         static const struct resource x86_resources[] = {
 381                 {
 382                         .start = 0xFED40000,
 383                         .end = 0xFED40000 + TIS_MEM_LEN - 1,
 384                         .flags = IORESOURCE_MEM,
 385                 },
 386         };
 387
 388         if (!force)
 389                 return 0;
 390
 391         /* The driver core will match the name tpm_tis of the device to
 392          * the tpm_tis platform driver and complete the setup via
 393          * tpm_tis_plat_probe
 394          */
 395         pdev = platform_device_register_simple("tpm_tis", -1, x86_resources,
 396                                                ARRAY_SIZE(x86_resources));
 397         if (IS_ERR(pdev))
 398                 return PTR_ERR(pdev);
 399         force_pdev = pdev;
 400
 401         return 0;
 402 }
 403
 404 static int __init init_tis(void)
 405 {
 406         int rc;
 407
 408         rc = tpm_tis_force_device();
 409         if (rc)
 410                 goto err_force;
 411
 412         rc = platform_driver_register(&tis_drv);
 413         if (rc)
 414                 goto err_platform;
 415
 416 #ifdef CONFIG_ACPI
 417         rc = acpi_bus_register_driver(&tis_acpi_driver);
 418         if (rc)
 419                 goto err_acpi;
 420 #endif
 421
 422         if (IS_ENABLED(CONFIG_PNP)) {
 423                 rc = pnp_register_driver(&tis_pnp_driver);
 424                 if (rc)
 425                         goto err_pnp;
 426         }
 427
 428         return 0;
 429
 430 err_pnp:
 431 #ifdef CONFIG_ACPI
 432         acpi_bus_unregister_driver(&tis_acpi_driver);
 433 err_acpi:
 434 #endif
 435         platform_device_unregister(force_pdev);
 436 err_platform:
 437         if (force_pdev)
 438                 platform_device_unregister(force_pdev);
 439 err_force:
 440         return rc;
 441 }
 442
 443 static void __exit cleanup_tis(void)
 444 {
 445         pnp_unregister_driver(&tis_pnp_driver);
 446 #ifdef CONFIG_ACPI
 447         acpi_bus_unregister_driver(&tis_acpi_driver);
 448 #endif
 449         platform_driver_unregister(&tis_drv);
 450
 451         if (force_pdev)
 452                 platform_device_unregister(force_pdev);
 453 }
 454
 455 module_init(init_tis);
 456 module_exit(cleanup_tis);
 457 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 458 MODULE_DESCRIPTION("TPM Driver");
 459 MODULE_VERSION("2.0");
 460 MODULE_LICENSE("GPL");