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