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 <linux/kernel.h>
  34 #include <linux/dmi.h>
  35 #include "tpm.h"
  36 #include "tpm_tis_core.h"
  37
  38 struct tpm_info {
  39         struct resource res;
  40         /* irq > 0 means: use irq $irq;
  41          * irq = 0 means: autoprobe for an irq;
  42          * irq = -1 means: no irq support
  43          */
  44         int irq;
  45 };
  46
  47 struct tpm_tis_tcg_phy {
  48         struct tpm_tis_data priv;
  49         void __iomem *iobase;
  50 };
  51
  52 static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data)
  53 {
  54         return container_of(data, struct tpm_tis_tcg_phy, priv);
  55 }
  56
  57 static int interrupts = -1;
  58 module_param(interrupts, int, 0444);
  59 MODULE_PARM_DESC(interrupts, "Enable interrupts");
  60
  61 static bool itpm;
  62 module_param(itpm, bool, 0444);
  63 MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
  64
  65 static bool force;
  66 #ifdef CONFIG_X86
  67 module_param(force, bool, 0444);
  68 MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
  69 #endif
  70
  71 static int tpm_tis_disable_irq(const struct dmi_system_id *d)
  72 {
  73         if (interrupts == -1) {
  74                 pr_notice("tpm_tis: %s detected: disabling interrupts.\n", d->ident);
  75                 interrupts = 0;
  76         }
  77
  78         return 0;
  79 }
  80
  81 static const struct dmi_system_id tpm_tis_dmi_table[] = {
  82         {
  83                 .callback = tpm_tis_disable_irq,
  84                 .ident = "ThinkPad T490s",
  85                 .matches = {
  86                         DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
  87                         DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T490s"),
  88                 },
  89         },
  90         {
  91                 .callback = tpm_tis_disable_irq,
  92                 .ident = "ThinkStation P360 Tiny",
  93                 .matches = {
  94                         DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
  95                         DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkStation P360 Tiny"),
  96                 },
  97         },
  98         {
  99                 .callback = tpm_tis_disable_irq,
 100                 .ident = "ThinkPad L490",
 101                 .matches = {
 102                         DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
 103                         DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad L490"),
 104                 },
 105         },
 106         {}
 107 };
 108
 109 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
 110 static int has_hid(struct acpi_device *dev, const char *hid)
 111 {
 112         struct acpi_hardware_id *id;
 113
 114         list_for_each_entry(id, &dev->pnp.ids, list)
 115                 if (!strcmp(hid, id->id))
 116                         return 1;
 117
 118         return 0;
 119 }
 120
 121 static inline int is_itpm(struct acpi_device *dev)
 122 {
 123         if (!dev)
 124                 return 0;
 125         return has_hid(dev, "INTC0102");
 126 }
 127 #else
 128 static inline int is_itpm(struct acpi_device *dev)
 129 {
 130         return 0;
 131 }
 132 #endif
 133
 134 #if defined(CONFIG_ACPI)
 135 #define DEVICE_IS_TPM2 1
 136
 137 static const struct acpi_device_id tpm_acpi_tbl[] = {
 138         {"MSFT0101", DEVICE_IS_TPM2},
 139         {},
 140 };
 141 MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);
 142
 143 static int check_acpi_tpm2(struct device *dev)
 144 {
 145         const struct acpi_device_id *aid = acpi_match_device(tpm_acpi_tbl, dev);
 146         struct acpi_table_tpm2 *tbl;
 147         acpi_status st;
 148         int ret = 0;
 149
 150         if (!aid || aid->driver_data != DEVICE_IS_TPM2)
 151                 return 0;
 152
 153         /* If the ACPI TPM2 signature is matched then a global ACPI_SIG_TPM2
 154          * table is mandatory
 155          */
 156         st = acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl);
 157         if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) {
 158                 dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n");
 159                 return -EINVAL;
 160         }
 161
 162         /* The tpm2_crb driver handles this device */
 163         if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
 164                 ret = -ENODEV;
 165
 166         acpi_put_table((struct acpi_table_header *)tbl);
 167         return ret;
 168 }
 169 #else
 170 static int check_acpi_tpm2(struct device *dev)
 171 {
 172         return 0;
 173 }
 174 #endif
 175
 176 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 177                               u8 *result)
 178 {
 179         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 180
 181         while (len--)
 182                 *result++ = ioread8(phy->iobase + addr);
 183
 184         return 0;
 185 }
 186
 187 static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 188                                const u8 *value)
 189 {
 190         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 191
 192         while (len--)
 193                 iowrite8(*value++, phy->iobase + addr);
 194
 195         return 0;
 196 }
 197
 198 static int tpm_tcg_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
 199 {
 200         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 201
 202         *result = ioread16(phy->iobase + addr);
 203
 204         return 0;
 205 }
 206
 207 static int tpm_tcg_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
 208 {
 209         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 210
 211         *result = ioread32(phy->iobase + addr);
 212
 213         return 0;
 214 }
 215
 216 static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
 217 {
 218         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 219
 220         iowrite32(value, phy->iobase + addr);
 221
 222         return 0;
 223 }
 224
 225 static const struct tpm_tis_phy_ops tpm_tcg = {
 226         .read_bytes = tpm_tcg_read_bytes,
 227         .write_bytes = tpm_tcg_write_bytes,
 228         .read16 = tpm_tcg_read16,
 229         .read32 = tpm_tcg_read32,
 230         .write32 = tpm_tcg_write32,
 231 };
 232
 233 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info)
 234 {
 235         struct tpm_tis_tcg_phy *phy;
 236         int irq = -1;
 237         int rc;
 238
 239         dmi_check_system(tpm_tis_dmi_table);
 240
 241         rc = check_acpi_tpm2(dev);
 242         if (rc)
 243                 return rc;
 244
 245         phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
 246         if (phy == NULL)
 247                 return -ENOMEM;
 248
 249         phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
 250         if (IS_ERR(phy->iobase))
 251                 return PTR_ERR(phy->iobase);
 252
 253         if (interrupts)
 254                 irq = tpm_info->irq;
 255
 256         if (itpm || is_itpm(ACPI_COMPANION(dev)))
 257                 phy->priv.flags |= TPM_TIS_ITPM_WORKAROUND;
 258
 259         return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
 260                                  ACPI_HANDLE(dev));
 261 }
 262
 263 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
 264
 265 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
 266                             const struct pnp_device_id *pnp_id)
 267 {
 268         struct tpm_info tpm_info = {};
 269         struct resource *res;
 270
 271         res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0);
 272         if (!res)
 273                 return -ENODEV;
 274         tpm_info.res = *res;
 275
 276         if (pnp_irq_valid(pnp_dev, 0))
 277                 tpm_info.irq = pnp_irq(pnp_dev, 0);
 278         else
 279                 tpm_info.irq = -1;
 280
 281         return tpm_tis_init(&pnp_dev->dev, &tpm_info);
 282 }
 283
 284 static struct pnp_device_id tpm_pnp_tbl[] = {
 285         {"PNP0C31", 0},         /* TPM */
 286         {"ATM1200", 0},         /* Atmel */
 287         {"IFX0102", 0},         /* Infineon */
 288         {"BCM0101", 0},         /* Broadcom */
 289         {"BCM0102", 0},         /* Broadcom */
 290         {"NSC1200", 0},         /* National */
 291         {"ICO0102", 0},         /* Intel */
 292         /* Add new here */
 293         {"", 0},                /* User Specified */
 294         {"", 0}                 /* Terminator */
 295 };
 296 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
 297
 298 static void tpm_tis_pnp_remove(struct pnp_dev *dev)
 299 {
 300         struct tpm_chip *chip = pnp_get_drvdata(dev);
 301
 302         tpm_chip_unregister(chip);
 303         tpm_tis_remove(chip);
 304 }
 305
 306 static struct pnp_driver tis_pnp_driver = {
 307         .name = "tpm_tis",
 308         .id_table = tpm_pnp_tbl,
 309         .probe = tpm_tis_pnp_init,
 310         .remove = tpm_tis_pnp_remove,
 311         .driver = {
 312                 .pm = &tpm_tis_pm,
 313         },
 314 };
 315
 316 #define TIS_HID_USR_IDX (ARRAY_SIZE(tpm_pnp_tbl) - 2)
 317 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
 318                     sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
 319 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
 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         tpm_info.irq = platform_get_irq(pdev, 0);
 336         if (tpm_info.irq <= 0) {
 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);
 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 #ifdef CONFIG_OF
 358 static const struct of_device_id tis_of_platform_match[] = {
 359         {.compatible = "tcg,tpm-tis-mmio"},
 360         {},
 361 };
 362 MODULE_DEVICE_TABLE(of, tis_of_platform_match);
 363 #endif
 364
 365 static struct platform_driver tis_drv = {
 366         .probe = tpm_tis_plat_probe,
 367         .remove = tpm_tis_plat_remove,
 368         .driver = {
 369                 .name           = "tpm_tis",
 370                 .pm             = &tpm_tis_pm,
 371                 .of_match_table = of_match_ptr(tis_of_platform_match),
 372                 .acpi_match_table = ACPI_PTR(tpm_acpi_tbl),
 373         },
 374 };
 375
 376 static int tpm_tis_force_device(void)
 377 {
 378         struct platform_device *pdev;
 379         static const struct resource x86_resources[] = {
 380                 {
 381                         .start = 0xFED40000,
 382                         .end = 0xFED40000 + TIS_MEM_LEN - 1,
 383                         .flags = IORESOURCE_MEM,
 384                 },
 385         };
 386
 387         if (!force)
 388                 return 0;
 389
 390         /* The driver core will match the name tpm_tis of the device to
 391          * the tpm_tis platform driver and complete the setup via
 392          * tpm_tis_plat_probe
 393          */
 394         pdev = platform_device_register_simple("tpm_tis", -1, x86_resources,
 395                                                ARRAY_SIZE(x86_resources));
 396         if (IS_ERR(pdev))
 397                 return PTR_ERR(pdev);
 398         force_pdev = pdev;
 399
 400         return 0;
 401 }
 402
 403 static int __init init_tis(void)
 404 {
 405         int rc;
 406
 407         rc = tpm_tis_force_device();
 408         if (rc)
 409                 goto err_force;
 410
 411         rc = platform_driver_register(&tis_drv);
 412         if (rc)
 413                 goto err_platform;
 414
 415
 416         if (IS_ENABLED(CONFIG_PNP)) {
 417                 rc = pnp_register_driver(&tis_pnp_driver);
 418                 if (rc)
 419                         goto err_pnp;
 420         }
 421
 422         return 0;
 423
 424 err_pnp:
 425         platform_driver_unregister(&tis_drv);
 426 err_platform:
 427         if (force_pdev)
 428                 platform_device_unregister(force_pdev);
 429 err_force:
 430         return rc;
 431 }
 432
 433 static void __exit cleanup_tis(void)
 434 {
 435         pnp_unregister_driver(&tis_pnp_driver);
 436         platform_driver_unregister(&tis_drv);
 437
 438         if (force_pdev)
 439                 platform_device_unregister(force_pdev);
 440 }
 441
 442 module_init(init_tis);
 443 module_exit(cleanup_tis);
 444 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 445 MODULE_DESCRIPTION("TPM Driver");
 446 MODULE_VERSION("2.0");
 447 MODULE_LICENSE("GPL");