1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2005, 2006 IBM Corporation 4 * Copyright (C) 2014, 2015 Intel Corporation 5 * 6 * Authors: 7 * Leendert van Doorn <leendert@watson.ibm.com> 8 * Kylene Hall <kjhall@us.ibm.com> 9 * 10 * Maintained by: <tpmdd-devel@lists.sourceforge.net> 11 * 12 * Device driver for TCG/TCPA TPM (trusted platform module). 13 * Specifications at www.trustedcomputinggroup.org 14 * 15 * This device driver implements the TPM interface as defined in 16 * the TCG TPM Interface Spec version 1.2, revision 1.0. 17 */ 18 #include <linux/init.h> 19 #include <linux/module.h> 20 #include <linux/moduleparam.h> 21 #include <linux/pnp.h> 22 #include <linux/slab.h> 23 #include <linux/interrupt.h> 24 #include <linux/wait.h> 25 #include <linux/acpi.h> 26 #include <linux/freezer.h> 27 #include <linux/of.h> 28 #include <linux/kernel.h> 29 #include "tpm.h" 30 #include "tpm_tis_core.h" 31 32 struct tpm_info { 33 struct resource res; 34 /* irq > 0 means: use irq $irq; 35 * irq = 0 means: autoprobe for an irq; 36 * irq = -1 means: no irq support 37 */ 38 int irq; 39 }; 40 41 struct tpm_tis_tcg_phy { 42 struct tpm_tis_data priv; 43 void __iomem *iobase; 44 }; 45 46 static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data) 47 { 48 return container_of(data, struct tpm_tis_tcg_phy, priv); 49 } 50 51 #ifdef CONFIG_PREEMPT_RT 52 /* 53 * Flush previous write operations with a dummy read operation to the 54 * TPM MMIO base address. 55 */ 56 static inline void tpm_tis_flush(void __iomem *iobase) 57 { 58 ioread8(iobase + TPM_ACCESS(0)); 59 } 60 #else 61 #define tpm_tis_flush(iobase) do { } while (0) 62 #endif 63 64 /* 65 * Write a byte word to the TPM MMIO address, and flush the write queue. 66 * The flush ensures that the data is sent immediately over the bus and not 67 * aggregated with further requests and transferred later in a batch. The large 68 * write requests can lead to unwanted latency spikes by blocking the CPU until 69 * the complete batch has been transferred. 70 */ 71 static inline void tpm_tis_iowrite8(u8 b, void __iomem *iobase, u32 addr) 72 { 73 iowrite8(b, iobase + addr); 74 tpm_tis_flush(iobase); 75 } 76 77 /* 78 * Write a 32-bit word to the TPM MMIO address, and flush the write queue. 79 * The flush ensures that the data is sent immediately over the bus and not 80 * aggregated with further requests and transferred later in a batch. The large 81 * write requests can lead to unwanted latency spikes by blocking the CPU until 82 * the complete batch has been transferred. 83 */ 84 static inline void tpm_tis_iowrite32(u32 b, void __iomem *iobase, u32 addr) 85 { 86 iowrite32(b, iobase + addr); 87 tpm_tis_flush(iobase); 88 } 89 90 static bool interrupts; 91 module_param(interrupts, bool, 0444); 92 MODULE_PARM_DESC(interrupts, "Enable interrupts"); 93 94 static bool itpm; 95 module_param(itpm, bool, 0444); 96 MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)"); 97 98 static bool force; 99 #ifdef CONFIG_X86 100 module_param(force, bool, 0444); 101 MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry"); 102 #endif 103 104 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI) 105 static int has_hid(struct acpi_device *dev, const char *hid) 106 { 107 struct acpi_hardware_id *id; 108 109 list_for_each_entry(id, &dev->pnp.ids, list) 110 if (!strcmp(hid, id->id)) 111 return 1; 112 113 return 0; 114 } 115 116 static inline int is_itpm(struct acpi_device *dev) 117 { 118 if (!dev) 119 return 0; 120 return has_hid(dev, "INTC0102"); 121 } 122 #else 123 static inline int is_itpm(struct acpi_device *dev) 124 { 125 return 0; 126 } 127 #endif 128 129 #if defined(CONFIG_ACPI) 130 #define DEVICE_IS_TPM2 1 131 132 static const struct acpi_device_id tpm_acpi_tbl[] = { 133 {"MSFT0101", DEVICE_IS_TPM2}, 134 {}, 135 }; 136 MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl); 137 138 static int check_acpi_tpm2(struct device *dev) 139 { 140 const struct acpi_device_id *aid = acpi_match_device(tpm_acpi_tbl, dev); 141 struct acpi_table_tpm2 *tbl; 142 acpi_status st; 143 int ret = 0; 144 145 if (!aid || aid->driver_data != DEVICE_IS_TPM2) 146 return 0; 147 148 /* If the ACPI TPM2 signature is matched then a global ACPI_SIG_TPM2 149 * table is mandatory 150 */ 151 st = acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl); 152 if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) { 153 dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n"); 154 return -EINVAL; 155 } 156 157 /* The tpm2_crb driver handles this device */ 158 if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED) 159 ret = -ENODEV; 160 161 acpi_put_table((struct acpi_table_header *)tbl); 162 return ret; 163 } 164 #else 165 static int check_acpi_tpm2(struct device *dev) 166 { 167 return 0; 168 } 169 #endif 170 171 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len, 172 u8 *result, enum tpm_tis_io_mode io_mode) 173 { 174 struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); 175 __le16 result_le16; 176 __le32 result_le32; 177 178 switch (io_mode) { 179 case TPM_TIS_PHYS_8: 180 while (len--) 181 *result++ = ioread8(phy->iobase + addr); 182 break; 183 case TPM_TIS_PHYS_16: 184 result_le16 = cpu_to_le16(ioread16(phy->iobase + addr)); 185 memcpy(result, &result_le16, sizeof(u16)); 186 break; 187 case TPM_TIS_PHYS_32: 188 result_le32 = cpu_to_le32(ioread32(phy->iobase + addr)); 189 memcpy(result, &result_le32, sizeof(u32)); 190 break; 191 } 192 193 return 0; 194 } 195 196 static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len, 197 const u8 *value, enum tpm_tis_io_mode io_mode) 198 { 199 struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data); 200 201 switch (io_mode) { 202 case TPM_TIS_PHYS_8: 203 while (len--) 204 tpm_tis_iowrite8(*value++, phy->iobase, addr); 205 break; 206 case TPM_TIS_PHYS_16: 207 return -EINVAL; 208 case TPM_TIS_PHYS_32: 209 tpm_tis_iowrite32(le32_to_cpu(*((__le32 *)value)), phy->iobase, addr); 210 break; 211 } 212 213 return 0; 214 } 215 216 static const struct tpm_tis_phy_ops tpm_tcg = { 217 .read_bytes = tpm_tcg_read_bytes, 218 .write_bytes = tpm_tcg_write_bytes, 219 }; 220 221 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info) 222 { 223 struct tpm_tis_tcg_phy *phy; 224 int irq = -1; 225 int rc; 226 227 rc = check_acpi_tpm2(dev); 228 if (rc) 229 return rc; 230 231 phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL); 232 if (phy == NULL) 233 return -ENOMEM; 234 235 phy->iobase = devm_ioremap_resource(dev, &tpm_info->res); 236 if (IS_ERR(phy->iobase)) 237 return PTR_ERR(phy->iobase); 238 239 if (interrupts) 240 irq = tpm_info->irq; 241 242 if (itpm || is_itpm(ACPI_COMPANION(dev))) 243 set_bit(TPM_TIS_ITPM_WORKAROUND, &phy->priv.flags); 244 245 return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg, 246 ACPI_HANDLE(dev)); 247 } 248 249 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume); 250 251 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev, 252 const struct pnp_device_id *pnp_id) 253 { 254 struct tpm_info tpm_info = {}; 255 struct resource *res; 256 257 res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0); 258 if (!res) 259 return -ENODEV; 260 tpm_info.res = *res; 261 262 if (pnp_irq_valid(pnp_dev, 0)) 263 tpm_info.irq = pnp_irq(pnp_dev, 0); 264 else 265 tpm_info.irq = -1; 266 267 return tpm_tis_init(&pnp_dev->dev, &tpm_info); 268 } 269 270 /* 271 * There is a known bug caused by 93e1b7d42e1e ("[PATCH] tpm: add HID module 272 * parameter"). This commit added IFX0102 device ID, which is also used by 273 * tpm_infineon but ignored to add quirks to probe which driver ought to be 274 * used. 275 */ 276 277 static struct pnp_device_id tpm_pnp_tbl[] = { 278 {"PNP0C31", 0}, /* TPM */ 279 {"ATM1200", 0}, /* Atmel */ 280 {"IFX0102", 0}, /* Infineon */ 281 {"BCM0101", 0}, /* Broadcom */ 282 {"BCM0102", 0}, /* Broadcom */ 283 {"NSC1200", 0}, /* National */ 284 {"ICO0102", 0}, /* Intel */ 285 /* Add new here */ 286 {"", 0}, /* User Specified */ 287 {"", 0} /* Terminator */ 288 }; 289 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl); 290 291 static void tpm_tis_pnp_remove(struct pnp_dev *dev) 292 { 293 struct tpm_chip *chip = pnp_get_drvdata(dev); 294 295 tpm_chip_unregister(chip); 296 tpm_tis_remove(chip); 297 } 298 299 static struct pnp_driver tis_pnp_driver = { 300 .name = "tpm_tis", 301 .id_table = tpm_pnp_tbl, 302 .probe = tpm_tis_pnp_init, 303 .remove = tpm_tis_pnp_remove, 304 .driver = { 305 .pm = &tpm_tis_pm, 306 }, 307 }; 308 309 #define TIS_HID_USR_IDX (ARRAY_SIZE(tpm_pnp_tbl) - 2) 310 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id, 311 sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444); 312 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe"); 313 314 static struct platform_device *force_pdev; 315 316 static int tpm_tis_plat_probe(struct platform_device *pdev) 317 { 318 struct tpm_info tpm_info = {}; 319 struct resource *res; 320 321 res = platform_get_resource(pdev, IORESOURCE_MEM, 0); 322 if (res == NULL) { 323 dev_err(&pdev->dev, "no memory resource defined\n"); 324 return -ENODEV; 325 } 326 tpm_info.res = *res; 327 328 tpm_info.irq = platform_get_irq_optional(pdev, 0); 329 if (tpm_info.irq <= 0) { 330 if (pdev != force_pdev) 331 tpm_info.irq = -1; 332 else 333 /* When forcing auto probe the IRQ */ 334 tpm_info.irq = 0; 335 } 336 337 return tpm_tis_init(&pdev->dev, &tpm_info); 338 } 339 340 static void tpm_tis_plat_remove(struct platform_device *pdev) 341 { 342 struct tpm_chip *chip = dev_get_drvdata(&pdev->dev); 343 344 tpm_chip_unregister(chip); 345 tpm_tis_remove(chip); 346 } 347 348 #ifdef CONFIG_OF 349 static const struct of_device_id tis_of_platform_match[] = { 350 {.compatible = "atmel,at97sc3204"}, 351 {.compatible = "tcg,tpm-tis-mmio"}, 352 {}, 353 }; 354 MODULE_DEVICE_TABLE(of, tis_of_platform_match); 355 #endif 356 357 static struct platform_driver tis_drv = { 358 .probe = tpm_tis_plat_probe, 359 .remove_new = tpm_tis_plat_remove, 360 .driver = { 361 .name = "tpm_tis", 362 .pm = &tpm_tis_pm, 363 .of_match_table = of_match_ptr(tis_of_platform_match), 364 .acpi_match_table = ACPI_PTR(tpm_acpi_tbl), 365 }, 366 }; 367 368 static int tpm_tis_force_device(void) 369 { 370 struct platform_device *pdev; 371 static const struct resource x86_resources[] = { 372 DEFINE_RES_MEM(0xFED40000, TIS_MEM_LEN) 373 }; 374 375 if (!force) 376 return 0; 377 378 /* The driver core will match the name tpm_tis of the device to 379 * the tpm_tis platform driver and complete the setup via 380 * tpm_tis_plat_probe 381 */ 382 pdev = platform_device_register_simple("tpm_tis", -1, x86_resources, 383 ARRAY_SIZE(x86_resources)); 384 if (IS_ERR(pdev)) 385 return PTR_ERR(pdev); 386 force_pdev = pdev; 387 388 return 0; 389 } 390 391 static int __init init_tis(void) 392 { 393 int rc; 394 395 rc = tpm_tis_force_device(); 396 if (rc) 397 goto err_force; 398 399 rc = platform_driver_register(&tis_drv); 400 if (rc) 401 goto err_platform; 402 403 404 if (IS_ENABLED(CONFIG_PNP)) { 405 rc = pnp_register_driver(&tis_pnp_driver); 406 if (rc) 407 goto err_pnp; 408 } 409 410 return 0; 411 412 err_pnp: 413 platform_driver_unregister(&tis_drv); 414 err_platform: 415 if (force_pdev) 416 platform_device_unregister(force_pdev); 417 err_force: 418 return rc; 419 } 420 421 static void __exit cleanup_tis(void) 422 { 423 pnp_unregister_driver(&tis_pnp_driver); 424 platform_driver_unregister(&tis_drv); 425 426 if (force_pdev) 427 platform_device_unregister(force_pdev); 428 } 429 430 module_init(init_tis); 431 module_exit(cleanup_tis); 432 MODULE_AUTHOR("Leendert van Doorn <leendert@watson.ibm.com>"); 433 MODULE_DESCRIPTION("TPM Driver"); 434 MODULE_VERSION("2.0"); 435 MODULE_LICENSE("GPL"); 436