xref: /openbmc/linux/drivers/char/tpm/tpm_tis.c (revision 2dd6532e)
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 static int interrupts = -1;
54 module_param(interrupts, int, 0444);
55 MODULE_PARM_DESC(interrupts, "Enable interrupts");
56 
57 static bool itpm;
58 module_param(itpm, bool, 0444);
59 MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
60 
61 static bool force;
62 #ifdef CONFIG_X86
63 module_param(force, bool, 0444);
64 MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
65 #endif
66 
67 static int tpm_tis_disable_irq(const struct dmi_system_id *d)
68 {
69 	if (interrupts == -1) {
70 		pr_notice("tpm_tis: %s detected: disabling interrupts.\n", d->ident);
71 		interrupts = 0;
72 	}
73 
74 	return 0;
75 }
76 
77 static const struct dmi_system_id tpm_tis_dmi_table[] = {
78 	{
79 		.callback = tpm_tis_disable_irq,
80 		.ident = "ThinkPad T490s",
81 		.matches = {
82 			DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"),
83 			DMI_MATCH(DMI_PRODUCT_VERSION, "ThinkPad T490s"),
84 		},
85 	},
86 	{}
87 };
88 
89 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
90 static int has_hid(struct acpi_device *dev, const char *hid)
91 {
92 	struct acpi_hardware_id *id;
93 
94 	list_for_each_entry(id, &dev->pnp.ids, list)
95 		if (!strcmp(hid, id->id))
96 			return 1;
97 
98 	return 0;
99 }
100 
101 static inline int is_itpm(struct acpi_device *dev)
102 {
103 	if (!dev)
104 		return 0;
105 	return has_hid(dev, "INTC0102");
106 }
107 #else
108 static inline int is_itpm(struct acpi_device *dev)
109 {
110 	return 0;
111 }
112 #endif
113 
114 #if defined(CONFIG_ACPI)
115 #define DEVICE_IS_TPM2 1
116 
117 static const struct acpi_device_id tpm_acpi_tbl[] = {
118 	{"MSFT0101", DEVICE_IS_TPM2},
119 	{},
120 };
121 MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);
122 
123 static int check_acpi_tpm2(struct device *dev)
124 {
125 	const struct acpi_device_id *aid = acpi_match_device(tpm_acpi_tbl, dev);
126 	struct acpi_table_tpm2 *tbl;
127 	acpi_status st;
128 
129 	if (!aid || aid->driver_data != DEVICE_IS_TPM2)
130 		return 0;
131 
132 	/* If the ACPI TPM2 signature is matched then a global ACPI_SIG_TPM2
133 	 * table is mandatory
134 	 */
135 	st =
136 	    acpi_get_table(ACPI_SIG_TPM2, 1, (struct acpi_table_header **)&tbl);
137 	if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) {
138 		dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n");
139 		return -EINVAL;
140 	}
141 
142 	/* The tpm2_crb driver handles this device */
143 	if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
144 		return -ENODEV;
145 
146 	return 0;
147 }
148 #else
149 static int check_acpi_tpm2(struct device *dev)
150 {
151 	return 0;
152 }
153 #endif
154 
155 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
156 			      u8 *result, enum tpm_tis_io_mode io_mode)
157 {
158 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
159 	__le16 result_le16;
160 	__le32 result_le32;
161 
162 	switch (io_mode) {
163 	case TPM_TIS_PHYS_8:
164 		while (len--)
165 			*result++ = ioread8(phy->iobase + addr);
166 		break;
167 	case TPM_TIS_PHYS_16:
168 		result_le16 = cpu_to_le16(ioread16(phy->iobase + addr));
169 		memcpy(result, &result_le16, sizeof(u16));
170 		break;
171 	case TPM_TIS_PHYS_32:
172 		result_le32 = cpu_to_le32(ioread32(phy->iobase + addr));
173 		memcpy(result, &result_le32, sizeof(u32));
174 		break;
175 	}
176 
177 	return 0;
178 }
179 
180 static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
181 			       const u8 *value, enum tpm_tis_io_mode io_mode)
182 {
183 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
184 
185 	switch (io_mode) {
186 	case TPM_TIS_PHYS_8:
187 		while (len--)
188 			iowrite8(*value++, phy->iobase + addr);
189 		break;
190 	case TPM_TIS_PHYS_16:
191 		return -EINVAL;
192 	case TPM_TIS_PHYS_32:
193 		iowrite32(le32_to_cpu(*((__le32 *)value)), phy->iobase + addr);
194 		break;
195 	}
196 
197 	return 0;
198 }
199 
200 static const struct tpm_tis_phy_ops tpm_tcg = {
201 	.read_bytes = tpm_tcg_read_bytes,
202 	.write_bytes = tpm_tcg_write_bytes,
203 };
204 
205 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info)
206 {
207 	struct tpm_tis_tcg_phy *phy;
208 	int irq = -1;
209 	int rc;
210 
211 	dmi_check_system(tpm_tis_dmi_table);
212 
213 	rc = check_acpi_tpm2(dev);
214 	if (rc)
215 		return rc;
216 
217 	phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
218 	if (phy == NULL)
219 		return -ENOMEM;
220 
221 	phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
222 	if (IS_ERR(phy->iobase))
223 		return PTR_ERR(phy->iobase);
224 
225 	if (interrupts)
226 		irq = tpm_info->irq;
227 
228 	if (itpm || is_itpm(ACPI_COMPANION(dev)))
229 		phy->priv.flags |= TPM_TIS_ITPM_WORKAROUND;
230 
231 	return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
232 				 ACPI_HANDLE(dev));
233 }
234 
235 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
236 
237 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
238 			    const struct pnp_device_id *pnp_id)
239 {
240 	struct tpm_info tpm_info = {};
241 	struct resource *res;
242 
243 	res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0);
244 	if (!res)
245 		return -ENODEV;
246 	tpm_info.res = *res;
247 
248 	if (pnp_irq_valid(pnp_dev, 0))
249 		tpm_info.irq = pnp_irq(pnp_dev, 0);
250 	else
251 		tpm_info.irq = -1;
252 
253 	return tpm_tis_init(&pnp_dev->dev, &tpm_info);
254 }
255 
256 /*
257  * There is a known bug caused by 93e1b7d42e1e ("[PATCH] tpm: add HID module
258  * parameter"). This commit added IFX0102 device ID, which is also used by
259  * tpm_infineon but ignored to add quirks to probe which driver ought to be
260  * used.
261  */
262 
263 static struct pnp_device_id tpm_pnp_tbl[] = {
264 	{"PNP0C31", 0},		/* TPM */
265 	{"ATM1200", 0},		/* Atmel */
266 	{"IFX0102", 0},		/* Infineon */
267 	{"BCM0101", 0},		/* Broadcom */
268 	{"BCM0102", 0},		/* Broadcom */
269 	{"NSC1200", 0},		/* National */
270 	{"ICO0102", 0},		/* Intel */
271 	/* Add new here */
272 	{"", 0},		/* User Specified */
273 	{"", 0}			/* Terminator */
274 };
275 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
276 
277 static void tpm_tis_pnp_remove(struct pnp_dev *dev)
278 {
279 	struct tpm_chip *chip = pnp_get_drvdata(dev);
280 
281 	tpm_chip_unregister(chip);
282 	tpm_tis_remove(chip);
283 }
284 
285 static struct pnp_driver tis_pnp_driver = {
286 	.name = "tpm_tis",
287 	.id_table = tpm_pnp_tbl,
288 	.probe = tpm_tis_pnp_init,
289 	.remove = tpm_tis_pnp_remove,
290 	.driver	= {
291 		.pm = &tpm_tis_pm,
292 	},
293 };
294 
295 #define TIS_HID_USR_IDX (ARRAY_SIZE(tpm_pnp_tbl) - 2)
296 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
297 		    sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
298 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
299 
300 static struct platform_device *force_pdev;
301 
302 static int tpm_tis_plat_probe(struct platform_device *pdev)
303 {
304 	struct tpm_info tpm_info = {};
305 	struct resource *res;
306 
307 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
308 	if (res == NULL) {
309 		dev_err(&pdev->dev, "no memory resource defined\n");
310 		return -ENODEV;
311 	}
312 	tpm_info.res = *res;
313 
314 	tpm_info.irq = platform_get_irq_optional(pdev, 0);
315 	if (tpm_info.irq <= 0) {
316 		if (pdev != force_pdev)
317 			tpm_info.irq = -1;
318 		else
319 			/* When forcing auto probe the IRQ */
320 			tpm_info.irq = 0;
321 	}
322 
323 	return tpm_tis_init(&pdev->dev, &tpm_info);
324 }
325 
326 static int tpm_tis_plat_remove(struct platform_device *pdev)
327 {
328 	struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
329 
330 	tpm_chip_unregister(chip);
331 	tpm_tis_remove(chip);
332 
333 	return 0;
334 }
335 
336 #ifdef CONFIG_OF
337 static const struct of_device_id tis_of_platform_match[] = {
338 	{.compatible = "tcg,tpm-tis-mmio"},
339 	{},
340 };
341 MODULE_DEVICE_TABLE(of, tis_of_platform_match);
342 #endif
343 
344 static struct platform_driver tis_drv = {
345 	.probe = tpm_tis_plat_probe,
346 	.remove = tpm_tis_plat_remove,
347 	.driver = {
348 		.name		= "tpm_tis",
349 		.pm		= &tpm_tis_pm,
350 		.of_match_table = of_match_ptr(tis_of_platform_match),
351 		.acpi_match_table = ACPI_PTR(tpm_acpi_tbl),
352 	},
353 };
354 
355 static int tpm_tis_force_device(void)
356 {
357 	struct platform_device *pdev;
358 	static const struct resource x86_resources[] = {
359 		DEFINE_RES_MEM(0xFED40000, TIS_MEM_LEN)
360 	};
361 
362 	if (!force)
363 		return 0;
364 
365 	/* The driver core will match the name tpm_tis of the device to
366 	 * the tpm_tis platform driver and complete the setup via
367 	 * tpm_tis_plat_probe
368 	 */
369 	pdev = platform_device_register_simple("tpm_tis", -1, x86_resources,
370 					       ARRAY_SIZE(x86_resources));
371 	if (IS_ERR(pdev))
372 		return PTR_ERR(pdev);
373 	force_pdev = pdev;
374 
375 	return 0;
376 }
377 
378 static int __init init_tis(void)
379 {
380 	int rc;
381 
382 	rc = tpm_tis_force_device();
383 	if (rc)
384 		goto err_force;
385 
386 	rc = platform_driver_register(&tis_drv);
387 	if (rc)
388 		goto err_platform;
389 
390 
391 	if (IS_ENABLED(CONFIG_PNP)) {
392 		rc = pnp_register_driver(&tis_pnp_driver);
393 		if (rc)
394 			goto err_pnp;
395 	}
396 
397 	return 0;
398 
399 err_pnp:
400 	platform_driver_unregister(&tis_drv);
401 err_platform:
402 	if (force_pdev)
403 		platform_device_unregister(force_pdev);
404 err_force:
405 	return rc;
406 }
407 
408 static void __exit cleanup_tis(void)
409 {
410 	pnp_unregister_driver(&tis_pnp_driver);
411 	platform_driver_unregister(&tis_drv);
412 
413 	if (force_pdev)
414 		platform_device_unregister(force_pdev);
415 }
416 
417 module_init(init_tis);
418 module_exit(cleanup_tis);
419 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
420 MODULE_DESCRIPTION("TPM Driver");
421 MODULE_VERSION("2.0");
422 MODULE_LICENSE("GPL");
423