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 };
  92
  93 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
  94 static int has_hid(struct acpi_device *dev, const char *hid)
  95 {
  96         struct acpi_hardware_id *id;
  97
  98         list_for_each_entry(id, &dev->pnp.ids, list)
  99                 if (!strcmp(hid, id->id))
 100                         return 1;
 101
 102         return 0;
 103 }
 104
 105 static inline int is_itpm(struct acpi_device *dev)
 106 {
 107         if (!dev)
 108                 return 0;
 109         return has_hid(dev, "INTC0102");
 110 }
 111 #else
 112 static inline int is_itpm(struct acpi_device *dev)
 113 {
 114         return 0;
 115 }
 116 #endif
 117
 118 #if defined(CONFIG_ACPI)
 119 #define DEVICE_IS_TPM2 1
 120
 121 static const struct acpi_device_id tpm_acpi_tbl[] = {
 122         {"MSFT0101", DEVICE_IS_TPM2},
 123         {},
 124 };
 125 MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);
 126
 127 static int check_acpi_tpm2(struct device *dev)
 128 {
 129         const struct acpi_device_id *aid = acpi_match_device(tpm_acpi_tbl, dev);
 130         struct acpi_table_tpm2 *tbl;
 131         acpi_status st;
 132
 133         if (!aid || aid->driver_data != DEVICE_IS_TPM2)
 134                 return 0;
 135
 136         /* If the ACPI TPM2 signature is matched then a global ACPI_SIG_TPM2
 137          * table is mandatory
 138          */
 139         st =
 140             acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl);
 141         if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) {
 142                 dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n");
 143                 return -EINVAL;
 144         }
 145
 146         /* The tpm2_crb driver handles this device */
 147         if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
 148                 return -ENODEV;
 149
 150         return 0;
 151 }
 152 #else
 153 static int check_acpi_tpm2(struct device *dev)
 154 {
 155         return 0;
 156 }
 157 #endif
 158
 159 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 160                               u8 *result)
 161 {
 162         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 163
 164         while (len--)
 165                 *result++ = ioread8(phy->iobase + addr);
 166
 167         return 0;
 168 }
 169
 170 static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
 171                                const u8 *value)
 172 {
 173         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 174
 175         while (len--)
 176                 iowrite8(*value++, phy->iobase + addr);
 177
 178         return 0;
 179 }
 180
 181 static int tpm_tcg_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
 182 {
 183         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 184
 185         *result = ioread16(phy->iobase + addr);
 186
 187         return 0;
 188 }
 189
 190 static int tpm_tcg_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
 191 {
 192         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 193
 194         *result = ioread32(phy->iobase + addr);
 195
 196         return 0;
 197 }
 198
 199 static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
 200 {
 201         struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
 202
 203         iowrite32(value, phy->iobase + addr);
 204
 205         return 0;
 206 }
 207
 208 static const struct tpm_tis_phy_ops tpm_tcg = {
 209         .read_bytes = tpm_tcg_read_bytes,
 210         .write_bytes = tpm_tcg_write_bytes,
 211         .read16 = tpm_tcg_read16,
 212         .read32 = tpm_tcg_read32,
 213         .write32 = tpm_tcg_write32,
 214 };
 215
 216 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info)
 217 {
 218         struct tpm_tis_tcg_phy *phy;
 219         int irq = -1;
 220         int rc;
 221
 222         dmi_check_system(tpm_tis_dmi_table);
 223
 224         rc = check_acpi_tpm2(dev);
 225         if (rc)
 226                 return rc;
 227
 228         phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
 229         if (phy == NULL)
 230                 return -ENOMEM;
 231
 232         phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
 233         if (IS_ERR(phy->iobase))
 234                 return PTR_ERR(phy->iobase);
 235
 236         if (interrupts)
 237                 irq = tpm_info->irq;
 238
 239         if (itpm || is_itpm(ACPI_COMPANION(dev)))
 240                 phy->priv.flags |= TPM_TIS_ITPM_WORKAROUND;
 241
 242         return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
 243                                  ACPI_HANDLE(dev));
 244 }
 245
 246 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
 247
 248 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
 249                             const struct pnp_device_id *pnp_id)
 250 {
 251         struct tpm_info tpm_info = {};
 252         struct resource *res;
 253
 254         res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0);
 255         if (!res)
 256                 return -ENODEV;
 257         tpm_info.res = *res;
 258
 259         if (pnp_irq_valid(pnp_dev, 0))
 260                 tpm_info.irq = pnp_irq(pnp_dev, 0);
 261         else
 262                 tpm_info.irq = -1;
 263
 264         return tpm_tis_init(&pnp_dev->dev, &tpm_info);
 265 }
 266
 267 static struct pnp_device_id tpm_pnp_tbl[] = {
 268         {"PNP0C31", 0},         /* TPM */
 269         {"ATM1200", 0},         /* Atmel */
 270         {"IFX0102", 0},         /* Infineon */
 271         {"BCM0101", 0},         /* Broadcom */
 272         {"BCM0102", 0},         /* Broadcom */
 273         {"NSC1200", 0},         /* National */
 274         {"ICO0102", 0},         /* Intel */
 275         /* Add new here */
 276         {"", 0},                /* User Specified */
 277         {"", 0}                 /* Terminator */
 278 };
 279 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
 280
 281 static void tpm_tis_pnp_remove(struct pnp_dev *dev)
 282 {
 283         struct tpm_chip *chip = pnp_get_drvdata(dev);
 284
 285         tpm_chip_unregister(chip);
 286         tpm_tis_remove(chip);
 287 }
 288
 289 static struct pnp_driver tis_pnp_driver = {
 290         .name = "tpm_tis",
 291         .id_table = tpm_pnp_tbl,
 292         .probe = tpm_tis_pnp_init,
 293         .remove = tpm_tis_pnp_remove,
 294         .driver = {
 295                 .pm = &tpm_tis_pm,
 296         },
 297 };
 298
 299 #define TIS_HID_USR_IDX (ARRAY_SIZE(tpm_pnp_tbl) - 2)
 300 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
 301                     sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
 302 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
 303
 304 static struct platform_device *force_pdev;
 305
 306 static int tpm_tis_plat_probe(struct platform_device *pdev)
 307 {
 308         struct tpm_info tpm_info = {};
 309         struct resource *res;
 310
 311         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
 312         if (res == NULL) {
 313                 dev_err(&pdev->dev, "no memory resource defined\n");
 314                 return -ENODEV;
 315         }
 316         tpm_info.res = *res;
 317
 318         tpm_info.irq = platform_get_irq(pdev, 0);
 319         if (tpm_info.irq <= 0) {
 320                 if (pdev != force_pdev)
 321                         tpm_info.irq = -1;
 322                 else
 323                         /* When forcing auto probe the IRQ */
 324                         tpm_info.irq = 0;
 325         }
 326
 327         return tpm_tis_init(&pdev->dev, &tpm_info);
 328 }
 329
 330 static int tpm_tis_plat_remove(struct platform_device *pdev)
 331 {
 332         struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
 333
 334         tpm_chip_unregister(chip);
 335         tpm_tis_remove(chip);
 336
 337         return 0;
 338 }
 339
 340 #ifdef CONFIG_OF
 341 static const struct of_device_id tis_of_platform_match[] = {
 342         {.compatible = "tcg,tpm-tis-mmio"},
 343         {},
 344 };
 345 MODULE_DEVICE_TABLE(of, tis_of_platform_match);
 346 #endif
 347
 348 static struct platform_driver tis_drv = {
 349         .probe = tpm_tis_plat_probe,
 350         .remove = tpm_tis_plat_remove,
 351         .driver = {
 352                 .name           = "tpm_tis",
 353                 .pm             = &tpm_tis_pm,
 354                 .of_match_table = of_match_ptr(tis_of_platform_match),
 355                 .acpi_match_table = ACPI_PTR(tpm_acpi_tbl),
 356         },
 357 };
 358
 359 static int tpm_tis_force_device(void)
 360 {
 361         struct platform_device *pdev;
 362         static const struct resource x86_resources[] = {
 363                 {
 364                         .start = 0xFED40000,
 365                         .end = 0xFED40000 + TIS_MEM_LEN - 1,
 366                         .flags = IORESOURCE_MEM,
 367                 },
 368         };
 369
 370         if (!force)
 371                 return 0;
 372
 373         /* The driver core will match the name tpm_tis of the device to
 374          * the tpm_tis platform driver and complete the setup via
 375          * tpm_tis_plat_probe
 376          */
 377         pdev = platform_device_register_simple("tpm_tis", -1, x86_resources,
 378                                                ARRAY_SIZE(x86_resources));
 379         if (IS_ERR(pdev))
 380                 return PTR_ERR(pdev);
 381         force_pdev = pdev;
 382
 383         return 0;
 384 }
 385
 386 static int __init init_tis(void)
 387 {
 388         int rc;
 389
 390         rc = tpm_tis_force_device();
 391         if (rc)
 392                 goto err_force;
 393
 394         rc = platform_driver_register(&tis_drv);
 395         if (rc)
 396                 goto err_platform;
 397
 398
 399         if (IS_ENABLED(CONFIG_PNP)) {
 400                 rc = pnp_register_driver(&tis_pnp_driver);
 401                 if (rc)
 402                         goto err_pnp;
 403         }
 404
 405         return 0;
 406
 407 err_pnp:
 408         platform_driver_unregister(&tis_drv);
 409 err_platform:
 410         if (force_pdev)
 411                 platform_device_unregister(force_pdev);
 412 err_force:
 413         return rc;
 414 }
 415
 416 static void __exit cleanup_tis(void)
 417 {
 418         pnp_unregister_driver(&tis_pnp_driver);
 419         platform_driver_unregister(&tis_drv);
 420
 421         if (force_pdev)
 422                 platform_device_unregister(force_pdev);
 423 }
 424
 425 module_init(init_tis);
 426 module_exit(cleanup_tis);
 427 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
 428 MODULE_DESCRIPTION("TPM Driver");
 429 MODULE_VERSION("2.0");
 430 MODULE_LICENSE("GPL");