xref: /openbmc/linux/drivers/char/tpm/tpm_tis.c (revision 4f6cce39)
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 "tpm.h"
34 #include "tpm_tis_core.h"
35 
36 struct tpm_info {
37 	struct resource res;
38 	/* irq > 0 means: use irq $irq;
39 	 * irq = 0 means: autoprobe for an irq;
40 	 * irq = -1 means: no irq support
41 	 */
42 	int irq;
43 };
44 
45 struct tpm_tis_tcg_phy {
46 	struct tpm_tis_data priv;
47 	void __iomem *iobase;
48 };
49 
50 static inline struct tpm_tis_tcg_phy *to_tpm_tis_tcg_phy(struct tpm_tis_data *data)
51 {
52 	return container_of(data, struct tpm_tis_tcg_phy, priv);
53 }
54 
55 static bool interrupts = true;
56 module_param(interrupts, bool, 0444);
57 MODULE_PARM_DESC(interrupts, "Enable interrupts");
58 
59 static bool itpm;
60 module_param(itpm, bool, 0444);
61 MODULE_PARM_DESC(itpm, "Force iTPM workarounds (found on some Lenovo laptops)");
62 
63 static bool force;
64 #ifdef CONFIG_X86
65 module_param(force, bool, 0444);
66 MODULE_PARM_DESC(force, "Force device probe rather than using ACPI entry");
67 #endif
68 
69 #if defined(CONFIG_PNP) && defined(CONFIG_ACPI)
70 static int has_hid(struct acpi_device *dev, const char *hid)
71 {
72 	struct acpi_hardware_id *id;
73 
74 	list_for_each_entry(id, &dev->pnp.ids, list)
75 		if (!strcmp(hid, id->id))
76 			return 1;
77 
78 	return 0;
79 }
80 
81 static inline int is_itpm(struct acpi_device *dev)
82 {
83 	return has_hid(dev, "INTC0102");
84 }
85 #else
86 static inline int is_itpm(struct acpi_device *dev)
87 {
88 	return 0;
89 }
90 #endif
91 
92 static int tpm_tcg_read_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
93 			      u8 *result)
94 {
95 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
96 
97 	while (len--)
98 		*result++ = ioread8(phy->iobase + addr);
99 	return 0;
100 }
101 
102 static int tpm_tcg_write_bytes(struct tpm_tis_data *data, u32 addr, u16 len,
103 			       u8 *value)
104 {
105 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
106 
107 	while (len--)
108 		iowrite8(*value++, phy->iobase + addr);
109 	return 0;
110 }
111 
112 static int tpm_tcg_read16(struct tpm_tis_data *data, u32 addr, u16 *result)
113 {
114 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
115 
116 	*result = ioread16(phy->iobase + addr);
117 	return 0;
118 }
119 
120 static int tpm_tcg_read32(struct tpm_tis_data *data, u32 addr, u32 *result)
121 {
122 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
123 
124 	*result = ioread32(phy->iobase + addr);
125 	return 0;
126 }
127 
128 static int tpm_tcg_write32(struct tpm_tis_data *data, u32 addr, u32 value)
129 {
130 	struct tpm_tis_tcg_phy *phy = to_tpm_tis_tcg_phy(data);
131 
132 	iowrite32(value, phy->iobase + addr);
133 	return 0;
134 }
135 
136 static const struct tpm_tis_phy_ops tpm_tcg = {
137 	.read_bytes = tpm_tcg_read_bytes,
138 	.write_bytes = tpm_tcg_write_bytes,
139 	.read16 = tpm_tcg_read16,
140 	.read32 = tpm_tcg_read32,
141 	.write32 = tpm_tcg_write32,
142 };
143 
144 static int tpm_tis_init(struct device *dev, struct tpm_info *tpm_info,
145 			acpi_handle acpi_dev_handle)
146 {
147 	struct tpm_tis_tcg_phy *phy;
148 	int irq = -1;
149 
150 	phy = devm_kzalloc(dev, sizeof(struct tpm_tis_tcg_phy), GFP_KERNEL);
151 	if (phy == NULL)
152 		return -ENOMEM;
153 
154 	phy->iobase = devm_ioremap_resource(dev, &tpm_info->res);
155 	if (IS_ERR(phy->iobase))
156 		return PTR_ERR(phy->iobase);
157 
158 	if (interrupts)
159 		irq = tpm_info->irq;
160 
161 	if (itpm)
162 		phy->priv.flags |= TPM_TIS_ITPM_WORKAROUND;
163 
164 	return tpm_tis_core_init(dev, &phy->priv, irq, &tpm_tcg,
165 				 acpi_dev_handle);
166 }
167 
168 static SIMPLE_DEV_PM_OPS(tpm_tis_pm, tpm_pm_suspend, tpm_tis_resume);
169 
170 static int tpm_tis_pnp_init(struct pnp_dev *pnp_dev,
171 			    const struct pnp_device_id *pnp_id)
172 {
173 	struct tpm_info tpm_info = {};
174 	acpi_handle acpi_dev_handle = NULL;
175 	struct resource *res;
176 
177 	res = pnp_get_resource(pnp_dev, IORESOURCE_MEM, 0);
178 	if (!res)
179 		return -ENODEV;
180 	tpm_info.res = *res;
181 
182 	if (pnp_irq_valid(pnp_dev, 0))
183 		tpm_info.irq = pnp_irq(pnp_dev, 0);
184 	else
185 		tpm_info.irq = -1;
186 
187 	if (pnp_acpi_device(pnp_dev)) {
188 		if (is_itpm(pnp_acpi_device(pnp_dev)))
189 			itpm = true;
190 
191 		acpi_dev_handle = ACPI_HANDLE(&pnp_dev->dev);
192 	}
193 
194 	return tpm_tis_init(&pnp_dev->dev, &tpm_info, acpi_dev_handle);
195 }
196 
197 static struct pnp_device_id tpm_pnp_tbl[] = {
198 	{"PNP0C31", 0},		/* TPM */
199 	{"ATM1200", 0},		/* Atmel */
200 	{"IFX0102", 0},		/* Infineon */
201 	{"BCM0101", 0},		/* Broadcom */
202 	{"BCM0102", 0},		/* Broadcom */
203 	{"NSC1200", 0},		/* National */
204 	{"ICO0102", 0},		/* Intel */
205 	/* Add new here */
206 	{"", 0},		/* User Specified */
207 	{"", 0}			/* Terminator */
208 };
209 MODULE_DEVICE_TABLE(pnp, tpm_pnp_tbl);
210 
211 static void tpm_tis_pnp_remove(struct pnp_dev *dev)
212 {
213 	struct tpm_chip *chip = pnp_get_drvdata(dev);
214 
215 	tpm_chip_unregister(chip);
216 	tpm_tis_remove(chip);
217 }
218 
219 static struct pnp_driver tis_pnp_driver = {
220 	.name = "tpm_tis",
221 	.id_table = tpm_pnp_tbl,
222 	.probe = tpm_tis_pnp_init,
223 	.remove = tpm_tis_pnp_remove,
224 	.driver	= {
225 		.pm = &tpm_tis_pm,
226 	},
227 };
228 
229 #define TIS_HID_USR_IDX sizeof(tpm_pnp_tbl)/sizeof(struct pnp_device_id) -2
230 module_param_string(hid, tpm_pnp_tbl[TIS_HID_USR_IDX].id,
231 		    sizeof(tpm_pnp_tbl[TIS_HID_USR_IDX].id), 0444);
232 MODULE_PARM_DESC(hid, "Set additional specific HID for this driver to probe");
233 
234 #ifdef CONFIG_ACPI
235 static int tpm_check_resource(struct acpi_resource *ares, void *data)
236 {
237 	struct tpm_info *tpm_info = (struct tpm_info *) data;
238 	struct resource res;
239 
240 	if (acpi_dev_resource_interrupt(ares, 0, &res))
241 		tpm_info->irq = res.start;
242 	else if (acpi_dev_resource_memory(ares, &res)) {
243 		tpm_info->res = res;
244 		tpm_info->res.name = NULL;
245 	}
246 
247 	return 1;
248 }
249 
250 static int tpm_tis_acpi_init(struct acpi_device *acpi_dev)
251 {
252 	struct acpi_table_tpm2 *tbl;
253 	acpi_status st;
254 	struct list_head resources;
255 	struct tpm_info tpm_info = {};
256 	int ret;
257 
258 	st = acpi_get_table(ACPI_SIG_TPM2, 1,
259 			    (struct acpi_table_header **) &tbl);
260 	if (ACPI_FAILURE(st) || tbl->header.length < sizeof(*tbl)) {
261 		dev_err(&acpi_dev->dev,
262 			FW_BUG "failed to get TPM2 ACPI table\n");
263 		return -EINVAL;
264 	}
265 
266 	if (tbl->start_method != ACPI_TPM2_MEMORY_MAPPED)
267 		return -ENODEV;
268 
269 	INIT_LIST_HEAD(&resources);
270 	tpm_info.irq = -1;
271 	ret = acpi_dev_get_resources(acpi_dev, &resources, tpm_check_resource,
272 				     &tpm_info);
273 	if (ret < 0)
274 		return ret;
275 
276 	acpi_dev_free_resource_list(&resources);
277 
278 	if (resource_type(&tpm_info.res) != IORESOURCE_MEM) {
279 		dev_err(&acpi_dev->dev,
280 			FW_BUG "TPM2 ACPI table does not define a memory resource\n");
281 		return -EINVAL;
282 	}
283 
284 	if (is_itpm(acpi_dev))
285 		itpm = true;
286 
287 	return tpm_tis_init(&acpi_dev->dev, &tpm_info, acpi_dev->handle);
288 }
289 
290 static int tpm_tis_acpi_remove(struct acpi_device *dev)
291 {
292 	struct tpm_chip *chip = dev_get_drvdata(&dev->dev);
293 
294 	tpm_chip_unregister(chip);
295 	tpm_tis_remove(chip);
296 
297 	return 0;
298 }
299 
300 static struct acpi_device_id tpm_acpi_tbl[] = {
301 	{"MSFT0101", 0},	/* TPM 2.0 */
302 	/* Add new here */
303 	{"", 0},		/* User Specified */
304 	{"", 0}			/* Terminator */
305 };
306 MODULE_DEVICE_TABLE(acpi, tpm_acpi_tbl);
307 
308 static struct acpi_driver tis_acpi_driver = {
309 	.name = "tpm_tis",
310 	.ids = tpm_acpi_tbl,
311 	.ops = {
312 		.add = tpm_tis_acpi_init,
313 		.remove = tpm_tis_acpi_remove,
314 	},
315 	.drv = {
316 		.pm = &tpm_tis_pm,
317 	},
318 };
319 #endif
320 
321 static struct platform_device *force_pdev;
322 
323 static int tpm_tis_plat_probe(struct platform_device *pdev)
324 {
325 	struct tpm_info tpm_info = {};
326 	struct resource *res;
327 
328 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
329 	if (res == NULL) {
330 		dev_err(&pdev->dev, "no memory resource defined\n");
331 		return -ENODEV;
332 	}
333 	tpm_info.res = *res;
334 
335 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
336 	if (res) {
337 		tpm_info.irq = res->start;
338 	} else {
339 		if (pdev == force_pdev)
340 			tpm_info.irq = -1;
341 		else
342 			/* When forcing auto probe the IRQ */
343 			tpm_info.irq = 0;
344 	}
345 
346 	return tpm_tis_init(&pdev->dev, &tpm_info, NULL);
347 }
348 
349 static int tpm_tis_plat_remove(struct platform_device *pdev)
350 {
351 	struct tpm_chip *chip = dev_get_drvdata(&pdev->dev);
352 
353 	tpm_chip_unregister(chip);
354 	tpm_tis_remove(chip);
355 
356 	return 0;
357 }
358 
359 #ifdef CONFIG_OF
360 static const struct of_device_id tis_of_platform_match[] = {
361 	{.compatible = "tcg,tpm-tis-mmio"},
362 	{},
363 };
364 MODULE_DEVICE_TABLE(of, tis_of_platform_match);
365 #endif
366 
367 static struct platform_driver tis_drv = {
368 	.probe = tpm_tis_plat_probe,
369 	.remove = tpm_tis_plat_remove,
370 	.driver = {
371 		.name		= "tpm_tis",
372 		.pm		= &tpm_tis_pm,
373 		.of_match_table = of_match_ptr(tis_of_platform_match),
374 	},
375 };
376 
377 static int tpm_tis_force_device(void)
378 {
379 	struct platform_device *pdev;
380 	static const struct resource x86_resources[] = {
381 		{
382 			.start = 0xFED40000,
383 			.end = 0xFED40000 + TIS_MEM_LEN - 1,
384 			.flags = IORESOURCE_MEM,
385 		},
386 	};
387 
388 	if (!force)
389 		return 0;
390 
391 	/* The driver core will match the name tpm_tis of the device to
392 	 * the tpm_tis platform driver and complete the setup via
393 	 * tpm_tis_plat_probe
394 	 */
395 	pdev = platform_device_register_simple("tpm_tis", -1, x86_resources,
396 					       ARRAY_SIZE(x86_resources));
397 	if (IS_ERR(pdev))
398 		return PTR_ERR(pdev);
399 	force_pdev = pdev;
400 
401 	return 0;
402 }
403 
404 static int __init init_tis(void)
405 {
406 	int rc;
407 
408 	rc = tpm_tis_force_device();
409 	if (rc)
410 		goto err_force;
411 
412 	rc = platform_driver_register(&tis_drv);
413 	if (rc)
414 		goto err_platform;
415 
416 #ifdef CONFIG_ACPI
417 	rc = acpi_bus_register_driver(&tis_acpi_driver);
418 	if (rc)
419 		goto err_acpi;
420 #endif
421 
422 	if (IS_ENABLED(CONFIG_PNP)) {
423 		rc = pnp_register_driver(&tis_pnp_driver);
424 		if (rc)
425 			goto err_pnp;
426 	}
427 
428 	return 0;
429 
430 err_pnp:
431 #ifdef CONFIG_ACPI
432 	acpi_bus_unregister_driver(&tis_acpi_driver);
433 err_acpi:
434 #endif
435 	platform_driver_unregister(&tis_drv);
436 err_platform:
437 	if (force_pdev)
438 		platform_device_unregister(force_pdev);
439 err_force:
440 	return rc;
441 }
442 
443 static void __exit cleanup_tis(void)
444 {
445 	pnp_unregister_driver(&tis_pnp_driver);
446 #ifdef CONFIG_ACPI
447 	acpi_bus_unregister_driver(&tis_acpi_driver);
448 #endif
449 	platform_driver_unregister(&tis_drv);
450 
451 	if (force_pdev)
452 		platform_device_unregister(force_pdev);
453 }
454 
455 module_init(init_tis);
456 module_exit(cleanup_tis);
457 MODULE_AUTHOR("Leendert van Doorn (leendert@watson.ibm.com)");
458 MODULE_DESCRIPTION("TPM Driver");
459 MODULE_VERSION("2.0");
460 MODULE_LICENSE("GPL");
461