xref: /openbmc/linux/drivers/char/tpm/tpm_tis.c (revision 88a6f899)
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/of_device.h>
29 #include <linux/kernel.h>
30 #include <linux/dmi.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 #ifdef CONFIG_PREEMPT_RT
54 /*
55  * Flush previous write operations with a dummy read operation to the
56  * TPM MMIO base address.
57  */
58 static inline void tpm_tis_flush(void __iomem *iobase)
59 {
60 	ioread8(iobase + TPM_ACCESS(0));
61 }
62 #else
63 #define tpm_tis_flush(iobase) do { } while (0)
64 #endif
65 
66 /*
67  * Write a byte word to the TPM MMIO address, and flush the write queue.
68  * The flush ensures that the data is sent immediately over the bus and not
69  * aggregated with further requests and transferred later in a batch. The large
70  * write requests can lead to unwanted latency spikes by blocking the CPU until
71  * the complete batch has been transferred.
72  */
73 static inline void tpm_tis_iowrite8(u8 b, void __iomem *iobase, u32 addr)
74 {
75 	iowrite8(b, iobase + addr);
76 	tpm_tis_flush(iobase);
77 }
78 
79 /*
80  * Write a 32-bit word to the TPM MMIO address, and flush the write queue.
81  * The flush ensures that the data is sent immediately over the bus and not
82  * aggregated with further requests and transferred later in a batch. The large
83  * write requests can lead to unwanted latency spikes by blocking the CPU until
84  * the complete batch has been transferred.
85  */
86 static inline void tpm_tis_iowrite32(u32 b, void __iomem *iobase, u32 addr)
87 {
88 	iowrite32(b, iobase + addr);
89 	tpm_tis_flush(iobase);
90 }
91 
92 static int interrupts = -1;
93 module_param(interrupts, int, 0444);
94 MODULE_PARM_DESC(interrupts, "Enable interrupts");
95 
96 static bool itpm;
97 module_param(itpm, bool, 0444);
98 MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
99 
100 static bool force;
101 #ifdef CONFIG_X86
102 module_param(force, bool, 0444);
103 MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
104 #endif
105 
106 static int tpm_tis_disable_irq(const struct dmi_system_id *d)
107 {
108 	if (interrupts == -1) {
109 		pr_notice("tpm_tis: %s detected: disabling interrupts.\n", d->ident);
110 		interrupts = 0;
111 	}
112 
113 	return 0;
114 }
115 
116 static const struct dmi_system_id tpm_tis_dmi_table[] = {
117 	{
118 		.callback = tpm_tis_disable_irq,
119 		.ident = "Framework Laptop (12th Gen Intel Core)",
120 		.matches = {
121 			DMI_MATCH(DMI_SYS_VENDOR, "Framework"),
122 			DMI_MATCH(DMI_PRODUCT_NAME, "Laptop (12th Gen Intel Core)"),
123 		},
124 	},
125 	{
126 		.callback = tpm_tis_disable_irq,
127 		.ident = "Framework Laptop (13th Gen Intel Core)",
128 		.matches = {
129 			DMI_MATCH(DMI_SYS_VENDOR, "Framework"),
130 			DMI_MATCH(DMI_PRODUCT_NAME, "Laptop (13th Gen Intel Core)"),
131 		},
132 	},
133 	{
134 		.callback = tpm_tis_disable_irq,
135 		.ident = "ThinkPad T490s",
136 		.matches = {
137 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
138 			DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T490s"),
139 		},
140 	},
141 	{
142 		.callback = tpm_tis_disable_irq,
143 		.ident = "ThinkStation P360 Tiny",
144 		.matches = {
145 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
146 			DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkStation P360 Tiny"),
147 		},
148 	},
149 	{
150 		.callback = tpm_tis_disable_irq,
151 		.ident = "ThinkPad L490",
152 		.matches = {
153 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
154 			DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad L490"),
155 		},
156 	},
157 	{
158 		.callback = tpm_tis_disable_irq,
159 		.ident = "ThinkPad L590",
160 		.matches = {
161 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
162 			DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad L590"),
163 		},
164 	},
165 	{
166 		.callback = tpm_tis_disable_irq,
167 		.ident = "UPX-TGL",
168 		.matches = {
169 			DMI_MATCH(DMI_SYS_VENDOR, "AAEON"),
170 			DMI_MATCH(DMI_PRODUCT_VERSION, "UPX-TGL"),
171 		},
172 	},
173 	{}
174 };
175 
176 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
177 static int has_hid(struct acpi_device *dev, const char *hid)
178 {
179 	struct acpi_hardware_id *id;
180 
181 	list_for_each_entry(id, &dev->pnp.ids, list)
182 		if (!strcmp(hid, id->id))
183 			return 1;
184 
185 	return 0;
186 }
187 
188 static inline int is_itpm(struct acpi_device *dev)
189 {
190 	if (!dev)
191 		return 0;
192 	return has_hid(dev, "INTC0102");
193 }
194 #else
195 static inline int is_itpm(struct acpi_device *dev)
196 {
197 	return 0;
198 }
199 #endif
200 
201 #if defined(CONFIG_ACPI)
202 #define DEVICE_IS_TPM2 1
203 
204 static const struct acpi_device_id tpm_acpi_tbl[] = {
205 	{"MSFT0101", DEVICE_IS_TPM2},
206 	{},
207 };
208 MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);
209 
210 static int check_acpi_tpm2(struct device *dev)
211 {
212 	const struct acpi_device_id *aid = acpi_match_device(tpm_acpi_tbl, dev);
213 	struct acpi_table_tpm2 *tbl;
214 	acpi_status st;
215 	int ret = 0;
216 
217 	if (!aid || aid->driver_data != DEVICE_IS_TPM2)
218 		return 0;
219 
220 	/* If the ACPI TPM2 signature is matched then a global ACPI_SIG_TPM2
221 	 * table is mandatory
222 	 */
223 	st = acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl);
224 	if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) {
225 		dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n");
226 		return -EINVAL;
227 	}
228 
229 	/* The tpm2_crb driver handles this device */
230 	if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
231 		ret = -ENODEV;
232 
233 	acpi_put_table((struct acpi_table_header *)tbl);
234 	return ret;
235 }
236 #else
237 static int check_acpi_tpm2(struct device *dev)
238 {
239 	return 0;
240 }
241 #endif
242 
243 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
244 			      u8 *result, enum tpm_tis_io_mode io_mode)
245 {
246 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
247 	__le16 result_le16;
248 	__le32 result_le32;
249 
250 	switch (io_mode) {
251 	case TPM_TIS_PHYS_8:
252 		while (len--)
253 			*result++ = ioread8(phy->iobase + addr);
254 		break;
255 	case TPM_TIS_PHYS_16:
256 		result_le16 = cpu_to_le16(ioread16(phy->iobase + addr));
257 		memcpy(result, &result_le16, sizeof(u16));
258 		break;
259 	case TPM_TIS_PHYS_32:
260 		result_le32 = cpu_to_le32(ioread32(phy->iobase + addr));
261 		memcpy(result, &result_le32, sizeof(u32));
262 		break;
263 	}
264 
265 	return 0;
266 }
267 
268 static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
269 			       const u8 *value, enum tpm_tis_io_mode io_mode)
270 {
271 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
272 
273 	switch (io_mode) {
274 	case TPM_TIS_PHYS_8:
275 		while (len--)
276 			tpm_tis_iowrite8(*value++, phy->iobase, addr);
277 		break;
278 	case TPM_TIS_PHYS_16:
279 		return -EINVAL;
280 	case TPM_TIS_PHYS_32:
281 		tpm_tis_iowrite32(le32_to_cpu(*((__le32 *)value)), phy->iobase, addr);
282 		break;
283 	}
284 
285 	return 0;
286 }
287 
288 static const struct tpm_tis_phy_ops tpm_tcg = {
289 	.read_bytes = tpm_tcg_read_bytes,
290 	.write_bytes = tpm_tcg_write_bytes,
291 };
292 
293 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info)
294 {
295 	struct tpm_tis_tcg_phy *phy;
296 	int irq = -1;
297 	int rc;
298 
299 	dmi_check_system(tpm_tis_dmi_table);
300 
301 	rc = check_acpi_tpm2(dev);
302 	if (rc)
303 		return rc;
304 
305 	phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
306 	if (phy == NULL)
307 		return -ENOMEM;
308 
309 	phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
310 	if (IS_ERR(phy->iobase))
311 		return PTR_ERR(phy->iobase);
312 
313 	if (interrupts)
314 		irq = tpm_info->irq;
315 
316 	if (itpm || is_itpm(ACPI_COMPANION(dev)))
317 		set_bit(TPM_TIS_ITPM_WORKAROUND, &phy->priv.flags);
318 
319 	return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
320 				 ACPI_HANDLE(dev));
321 }
322 
323 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
324 
325 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
326 			    const struct pnp_device_id *pnp_id)
327 {
328 	struct tpm_info tpm_info = {};
329 	struct resource *res;
330 
331 	res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0);
332 	if (!res)
333 		return -ENODEV;
334 	tpm_info.res = *res;
335 
336 	if (pnp_irq_valid(pnp_dev, 0))
337 		tpm_info.irq = pnp_irq(pnp_dev, 0);
338 	else
339 		tpm_info.irq = -1;
340 
341 	return tpm_tis_init(&pnp_dev->dev, &tpm_info);
342 }
343 
344 /*
345  * There is a known bug caused by 93e1b7d42e1e ("[PATCH] tpm: add HID module
346  * parameter"). This commit added IFX0102 device ID, which is also used by
347  * tpm_infineon but ignored to add quirks to probe which driver ought to be
348  * used.
349  */
350 
351 static struct pnp_device_id tpm_pnp_tbl[] = {
352 	{"PNP0C31", 0},		/* TPM */
353 	{"ATM1200", 0},		/* Atmel */
354 	{"IFX0102", 0},		/* Infineon */
355 	{"BCM0101", 0},		/* Broadcom */
356 	{"BCM0102", 0},		/* Broadcom */
357 	{"NSC1200", 0},		/* National */
358 	{"ICO0102", 0},		/* Intel */
359 	/* Add new here */
360 	{"", 0},		/* User Specified */
361 	{"", 0}			/* Terminator */
362 };
363 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
364 
365 static void tpm_tis_pnp_remove(struct pnp_dev *dev)
366 {
367 	struct tpm_chip *chip = pnp_get_drvdata(dev);
368 
369 	tpm_chip_unregister(chip);
370 	tpm_tis_remove(chip);
371 }
372 
373 static struct pnp_driver tis_pnp_driver = {
374 	.name = "tpm_tis",
375 	.id_table = tpm_pnp_tbl,
376 	.probe = tpm_tis_pnp_init,
377 	.remove = tpm_tis_pnp_remove,
378 	.driver	= {
379 		.pm = &tpm_tis_pm,
380 	},
381 };
382 
383 #define TIS_HID_USR_IDX (ARRAY_SIZE(tpm_pnp_tbl) - 2)
384 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
385 		    sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
386 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
387 
388 static struct platform_device *force_pdev;
389 
390 static int tpm_tis_plat_probe(struct platform_device *pdev)
391 {
392 	struct tpm_info tpm_info = {};
393 	struct resource *res;
394 
395 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
396 	if (res == NULL) {
397 		dev_err(&pdev->dev, "no memory resource defined\n");
398 		return -ENODEV;
399 	}
400 	tpm_info.res = *res;
401 
402 	tpm_info.irq = platform_get_irq_optional(pdev, 0);
403 	if (tpm_info.irq <= 0) {
404 		if (pdev != force_pdev)
405 			tpm_info.irq = -1;
406 		else
407 			/* When forcing auto probe the IRQ */
408 			tpm_info.irq = 0;
409 	}
410 
411 	return tpm_tis_init(&pdev->dev, &tpm_info);
412 }
413 
414 static void tpm_tis_plat_remove(struct platform_device *pdev)
415 {
416 	struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
417 
418 	tpm_chip_unregister(chip);
419 	tpm_tis_remove(chip);
420 }
421 
422 #ifdef CONFIG_OF
423 static const struct of_device_id tis_of_platform_match[] = {
424 	{.compatible = "tcg,tpm-tis-mmio"},
425 	{},
426 };
427 MODULE_DEVICE_TABLE(of, tis_of_platform_match);
428 #endif
429 
430 static struct platform_driver tis_drv = {
431 	.probe = tpm_tis_plat_probe,
432 	.remove_new = tpm_tis_plat_remove,
433 	.driver = {
434 		.name		= "tpm_tis",
435 		.pm		= &tpm_tis_pm,
436 		.of_match_table = of_match_ptr(tis_of_platform_match),
437 		.acpi_match_table = ACPI_PTR(tpm_acpi_tbl),
438 	},
439 };
440 
441 static int tpm_tis_force_device(void)
442 {
443 	struct platform_device *pdev;
444 	static const struct resource x86_resources[] = {
445 		DEFINE_RES_MEM(0xFED40000, TIS_MEM_LEN)
446 	};
447 
448 	if (!force)
449 		return 0;
450 
451 	/* The driver core will match the name tpm_tis of the device to
452 	 * the tpm_tis platform driver and complete the setup via
453 	 * tpm_tis_plat_probe
454 	 */
455 	pdev = platform_device_register_simple("tpm_tis", -1, x86_resources,
456 					       ARRAY_SIZE(x86_resources));
457 	if (IS_ERR(pdev))
458 		return PTR_ERR(pdev);
459 	force_pdev = pdev;
460 
461 	return 0;
462 }
463 
464 static int __init init_tis(void)
465 {
466 	int rc;
467 
468 	rc = tpm_tis_force_device();
469 	if (rc)
470 		goto err_force;
471 
472 	rc = platform_driver_register(&tis_drv);
473 	if (rc)
474 		goto err_platform;
475 
476 
477 	if (IS_ENABLED(CONFIG_PNP)) {
478 		rc = pnp_register_driver(&tis_pnp_driver);
479 		if (rc)
480 			goto err_pnp;
481 	}
482 
483 	return 0;
484 
485 err_pnp:
486 	platform_driver_unregister(&tis_drv);
487 err_platform:
488 	if (force_pdev)
489 		platform_device_unregister(force_pdev);
490 err_force:
491 	return rc;
492 }
493 
494 static void __exit cleanup_tis(void)
495 {
496 	pnp_unregister_driver(&tis_pnp_driver);
497 	platform_driver_unregister(&tis_drv);
498 
499 	if (force_pdev)
500 		platform_device_unregister(force_pdev);
501 }
502 
503 module_init(init_tis);
504 module_exit(cleanup_tis);
505 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
506 MODULE_DESCRIPTION("TPM Driver");
507 MODULE_VERSION("2.0");
508 MODULE_LICENSE("GPL");
509