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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * Copyright (C) 2005, 2006 IBM Corporation4 * Copyright (C) 2014, 2015 Intel Corporation5 *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.org14 *15 * This device driver implements the TPM interface as defined in16 * 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 32struct 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 support37 */38 int irq;39};40 41struct tpm_tis_tcg_phy {42 struct tpm_tis_data priv;43 void __iomem *iobase;44};45 46static 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_RT52/*53 * Flush previous write operations with a dummy read operation to the54 * TPM MMIO base address.55 */56static inline void tpm_tis_flush(void __iomem *iobase)57{58 ioread8(iobase + TPM_ACCESS(0));59}60#else61#define tpm_tis_flush(iobase) do { } while (0)62#endif63 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 not67 * aggregated with further requests and transferred later in a batch. The large68 * write requests can lead to unwanted latency spikes by blocking the CPU until69 * the complete batch has been transferred.70 */71static 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 not80 * aggregated with further requests and transferred later in a batch. The large81 * write requests can lead to unwanted latency spikes by blocking the CPU until82 * the complete batch has been transferred.83 */84static 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 90static bool interrupts;91module_param(interrupts, bool, 0444);92MODULE_PARM_DESC(interrupts, "Enable interrupts");93 94static bool itpm;95module_param(itpm, bool, 0444);96MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");97 98static bool force;99#ifdef CONFIG_X86100module_param(force, bool, 0444);101MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");102#endif103 104#if defined(CONFIG_PNP) && defined(CONFIG_ACPI)105static 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 116static inline int is_itpm(struct acpi_device *dev)117{118 if (!dev)119 return 0;120 return has_hid(dev, "INTC0102");121}122#else123static inline int is_itpm(struct acpi_device *dev)124{125 return 0;126}127#endif128 129#if defined(CONFIG_ACPI)130#define DEVICE_IS_TPM2 1131 132static const struct acpi_device_id tpm_acpi_tbl[] = {133 {"MSFT0101", DEVICE_IS_TPM2},134 {},135};136MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);137 138static 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_TPM2149 * table is mandatory150 */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#else165static int check_acpi_tpm2(struct device *dev)166{167 return 0;168}169#endif170 171static 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 196static 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 216static const struct tpm_tis_phy_ops tpm_tcg = {217 .read_bytes = tpm_tcg_read_bytes,218 .write_bytes = tpm_tcg_write_bytes,219};220 221static 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 249static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);250 251static 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 else265 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 module272 * parameter"). This commit added IFX0102 device ID, which is also used by273 * tpm_infineon but ignored to add quirks to probe which driver ought to be274 * used.275 */276 277static 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};289MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);290 291static 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 299static 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)310module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,311 sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);312MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");313 314static struct platform_device *force_pdev;315 316static 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 else333 /* When forcing auto probe the IRQ */334 tpm_info.irq = 0;335 }336 337 return tpm_tis_init(&pdev->dev, &tpm_info);338}339 340static 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_OF349static const struct of_device_id tis_of_platform_match[] = {350 {.compatible = "atmel,at97sc3204"},351 {.compatible = "tcg,tpm-tis-mmio"},352 {},353};354MODULE_DEVICE_TABLE(of, tis_of_platform_match);355#endif356 357static 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 368static 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 to379 * the tpm_tis platform driver and complete the setup via380 * tpm_tis_plat_probe381 */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 391static 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 412err_pnp:413 platform_driver_unregister(&tis_drv);414err_platform:415 if (force_pdev)416 platform_device_unregister(force_pdev);417err_force:418 return rc;419}420 421static 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 430module_init(init_tis);431module_exit(cleanup_tis);432MODULE_AUTHOR("Leendert van Doorn <leendert@watson.ibm.com>");433MODULE_DESCRIPTION("TPM Driver");434MODULE_VERSION("2.0");435MODULE_LICENSE("GPL");436