Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid
[linux-2.6-block.git] / drivers / char / tpm / tpm_crb.c
CommitLineData
30fc8d13
JS
1/*
2 * Copyright (C) 2014 Intel Corporation
3 *
4 * Authors:
5 * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
6 *
7 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
8 *
9 * This device driver implements the TPM interface as defined in
10 * the TCG CRB 2.0 TPM specification.
11 *
12 * This program is free software; you can redistribute it and/or
13 * modify it under the terms of the GNU General Public License
14 * as published by the Free Software Foundation; version 2
15 * of the License.
16 */
17
18#include <linux/acpi.h>
19#include <linux/highmem.h>
20#include <linux/rculist.h>
21#include <linux/module.h>
22#include <linux/platform_device.h>
23#include "tpm.h"
24
25#define ACPI_SIG_TPM2 "TPM2"
26
27static const u8 CRB_ACPI_START_UUID[] = {
28 /* 0000 */ 0xAB, 0x6C, 0xBF, 0x6B, 0x63, 0x54, 0x14, 0x47,
29 /* 0008 */ 0xB7, 0xCD, 0xF0, 0x20, 0x3C, 0x03, 0x68, 0xD4
30};
31
32enum crb_defaults {
33 CRB_ACPI_START_REVISION_ID = 1,
34 CRB_ACPI_START_INDEX = 1,
35};
36
30fc8d13
JS
37enum crb_ca_request {
38 CRB_CA_REQ_GO_IDLE = BIT(0),
39 CRB_CA_REQ_CMD_READY = BIT(1),
40};
41
42enum crb_ca_status {
43 CRB_CA_STS_ERROR = BIT(0),
44 CRB_CA_STS_TPM_IDLE = BIT(1),
45};
46
47enum crb_start {
48 CRB_START_INVOKE = BIT(0),
49};
50
51enum crb_cancel {
52 CRB_CANCEL_INVOKE = BIT(0),
53};
54
55struct crb_control_area {
56 u32 req;
57 u32 sts;
58 u32 cancel;
59 u32 start;
60 u32 int_enable;
61 u32 int_sts;
62 u32 cmd_size;
149789ce
JS
63 u32 cmd_pa_low;
64 u32 cmd_pa_high;
30fc8d13
JS
65 u32 rsp_size;
66 u64 rsp_pa;
67} __packed;
68
69enum crb_status {
70 CRB_STS_COMPLETE = BIT(0),
71};
72
73enum crb_flags {
74 CRB_FL_ACPI_START = BIT(0),
75 CRB_FL_CRB_START = BIT(1),
76};
77
78struct crb_priv {
79 unsigned int flags;
1bd047be
JG
80 struct resource res;
81 void __iomem *iobase;
30fc8d13
JS
82 struct crb_control_area __iomem *cca;
83 u8 __iomem *cmd;
84 u8 __iomem *rsp;
85};
86
74d6b3ce 87static SIMPLE_DEV_PM_OPS(crb_pm, tpm_pm_suspend, tpm_pm_resume);
30fc8d13
JS
88
89static u8 crb_status(struct tpm_chip *chip)
90{
91 struct crb_priv *priv = chip->vendor.priv;
92 u8 sts = 0;
93
1e3ed59d 94 if ((ioread32(&priv->cca->start) & CRB_START_INVOKE) !=
30fc8d13
JS
95 CRB_START_INVOKE)
96 sts |= CRB_STS_COMPLETE;
97
98 return sts;
99}
100
101static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count)
102{
103 struct crb_priv *priv = chip->vendor.priv;
104 unsigned int expected;
105
106 /* sanity check */
107 if (count < 6)
108 return -EIO;
109
1e3ed59d 110 if (ioread32(&priv->cca->sts) & CRB_CA_STS_ERROR)
30fc8d13
JS
111 return -EIO;
112
113 memcpy_fromio(buf, priv->rsp, 6);
114 expected = be32_to_cpup((__be32 *) &buf[2]);
115
116 if (expected > count)
117 return -EIO;
118
119 memcpy_fromio(&buf[6], &priv->rsp[6], expected - 6);
120
121 return expected;
122}
123
124static int crb_do_acpi_start(struct tpm_chip *chip)
125{
126 union acpi_object *obj;
127 int rc;
128
129 obj = acpi_evaluate_dsm(chip->acpi_dev_handle,
130 CRB_ACPI_START_UUID,
131 CRB_ACPI_START_REVISION_ID,
132 CRB_ACPI_START_INDEX,
133 NULL);
134 if (!obj)
135 return -ENXIO;
136 rc = obj->integer.value == 0 ? 0 : -ENXIO;
137 ACPI_FREE(obj);
138 return rc;
139}
140
141static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
142{
143 struct crb_priv *priv = chip->vendor.priv;
144 int rc = 0;
145
1e3ed59d 146 if (len > ioread32(&priv->cca->cmd_size)) {
30fc8d13
JS
147 dev_err(&chip->dev,
148 "invalid command count value %x %zx\n",
149 (unsigned int) len,
1e3ed59d 150 (size_t) ioread32(&priv->cca->cmd_size));
30fc8d13
JS
151 return -E2BIG;
152 }
153
154 memcpy_toio(priv->cmd, buf, len);
155
156 /* Make sure that cmd is populated before issuing start. */
157 wmb();
158
159 if (priv->flags & CRB_FL_CRB_START)
160 iowrite32(cpu_to_le32(CRB_START_INVOKE), &priv->cca->start);
161
162 if (priv->flags & CRB_FL_ACPI_START)
163 rc = crb_do_acpi_start(chip);
164
165 return rc;
166}
167
168static void crb_cancel(struct tpm_chip *chip)
169{
170 struct crb_priv *priv = chip->vendor.priv;
171
172 iowrite32(cpu_to_le32(CRB_CANCEL_INVOKE), &priv->cca->cancel);
173
174 /* Make sure that cmd is populated before issuing cancel. */
175 wmb();
176
177 if ((priv->flags & CRB_FL_ACPI_START) && crb_do_acpi_start(chip))
178 dev_err(&chip->dev, "ACPI Start failed\n");
179
180 iowrite32(0, &priv->cca->cancel);
181}
182
183static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
184{
185 struct crb_priv *priv = chip->vendor.priv;
1e3ed59d 186 u32 cancel = ioread32(&priv->cca->cancel);
30fc8d13
JS
187
188 return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE;
189}
190
191static const struct tpm_class_ops tpm_crb = {
192 .status = crb_status,
193 .recv = crb_recv,
194 .send = crb_send,
195 .cancel = crb_cancel,
196 .req_canceled = crb_req_canceled,
197 .req_complete_mask = CRB_STS_COMPLETE,
198 .req_complete_val = CRB_STS_COMPLETE,
199};
200
1bd047be 201static int crb_init(struct acpi_device *device, struct crb_priv *priv)
30fc8d13
JS
202{
203 struct tpm_chip *chip;
1bd047be
JG
204 int rc;
205
206 chip = tpmm_chip_alloc(&device->dev, &tpm_crb);
207 if (IS_ERR(chip))
208 return PTR_ERR(chip);
209
210 chip->vendor.priv = priv;
211 chip->acpi_dev_handle = device->handle;
212 chip->flags = TPM_CHIP_FLAG_TPM2;
213
214 rc = tpm_get_timeouts(chip);
215 if (rc)
216 return rc;
217
218 rc = tpm2_do_selftest(chip);
219 if (rc)
220 return rc;
221
222 return tpm_chip_register(chip);
223}
224
225static int crb_check_resource(struct acpi_resource *ares, void *data)
226{
227 struct crb_priv *priv = data;
228 struct resource res;
229
30f9c8c9 230 if (acpi_dev_resource_memory(ares, &res)) {
1bd047be 231 priv->res = res;
30f9c8c9
JS
232 priv->res.name = NULL;
233 }
1bd047be
JG
234
235 return 1;
236}
237
238static void __iomem *crb_map_res(struct device *dev, struct crb_priv *priv,
239 u64 start, u32 size)
240{
241 struct resource new_res = {
242 .start = start,
243 .end = start + size - 1,
244 .flags = IORESOURCE_MEM,
245 };
246
247 /* Detect a 64 bit address on a 32 bit system */
248 if (start != new_res.start)
249 return ERR_PTR(-EINVAL);
250
251 if (!resource_contains(&priv->res, &new_res))
252 return devm_ioremap_resource(dev, &new_res);
253
254 return priv->iobase + (new_res.start - priv->res.start);
255}
256
257static int crb_map_io(struct acpi_device *device, struct crb_priv *priv,
258 struct acpi_table_tpm2 *buf)
259{
260 struct list_head resources;
261 struct device *dev = &device->dev;
262 u64 pa;
263 int ret;
264
265 INIT_LIST_HEAD(&resources);
266 ret = acpi_dev_get_resources(device, &resources, crb_check_resource,
267 priv);
268 if (ret < 0)
269 return ret;
270 acpi_dev_free_resource_list(&resources);
271
272 if (resource_type(&priv->res) != IORESOURCE_MEM) {
273 dev_err(dev,
274 FW_BUG "TPM2 ACPI table does not define a memory resource\n");
275 return -EINVAL;
276 }
277
278 priv->iobase = devm_ioremap_resource(dev, &priv->res);
279 if (IS_ERR(priv->iobase))
280 return PTR_ERR(priv->iobase);
281
282 priv->cca = crb_map_res(dev, priv, buf->control_address, 0x1000);
283 if (IS_ERR(priv->cca))
284 return PTR_ERR(priv->cca);
285
286 pa = ((u64) ioread32(&priv->cca->cmd_pa_high) << 32) |
287 (u64) ioread32(&priv->cca->cmd_pa_low);
288 priv->cmd = crb_map_res(dev, priv, pa, ioread32(&priv->cca->cmd_size));
289 if (IS_ERR(priv->cmd))
290 return PTR_ERR(priv->cmd);
291
292 memcpy_fromio(&pa, &priv->cca->rsp_pa, 8);
293 pa = le64_to_cpu(pa);
294 priv->rsp = crb_map_res(dev, priv, pa, ioread32(&priv->cca->rsp_size));
295 return PTR_ERR_OR_ZERO(priv->rsp);
296}
297
298static int crb_acpi_add(struct acpi_device *device)
299{
55a889c2 300 struct acpi_table_tpm2 *buf;
30fc8d13
JS
301 struct crb_priv *priv;
302 struct device *dev = &device->dev;
303 acpi_status status;
304 u32 sm;
30fc8d13
JS
305 int rc;
306
30fc8d13
JS
307 status = acpi_get_table(ACPI_SIG_TPM2, 1,
308 (struct acpi_table_header **) &buf);
55a889c2
JG
309 if (ACPI_FAILURE(status) || buf->header.length < sizeof(*buf)) {
310 dev_err(dev, FW_BUG "failed to get TPM2 ACPI table\n");
1bd047be 311 return -EINVAL;
30fc8d13
JS
312 }
313
399235dc 314 /* Should the FIFO driver handle this? */
55a889c2
JG
315 sm = buf->start_method;
316 if (sm == ACPI_TPM2_MEMORY_MAPPED)
399235dc
JS
317 return -ENODEV;
318
1bd047be
JG
319 priv = devm_kzalloc(dev, sizeof(struct crb_priv), GFP_KERNEL);
320 if (!priv)
30fc8d13 321 return -ENOMEM;
30fc8d13 322
30fc8d13
JS
323 /* The reason for the extra quirk is that the PTT in 4th Gen Core CPUs
324 * report only ACPI start but in practice seems to require both
325 * ACPI start and CRB start.
326 */
55a889c2 327 if (sm == ACPI_TPM2_COMMAND_BUFFER || sm == ACPI_TPM2_MEMORY_MAPPED ||
30fc8d13
JS
328 !strcmp(acpi_device_hid(device), "MSFT0101"))
329 priv->flags |= CRB_FL_CRB_START;
330
55a889c2
JG
331 if (sm == ACPI_TPM2_START_METHOD ||
332 sm == ACPI_TPM2_COMMAND_BUFFER_WITH_START_METHOD)
30fc8d13
JS
333 priv->flags |= CRB_FL_ACPI_START;
334
1bd047be 335 rc = crb_map_io(device, priv, buf);
25112048
JG
336 if (rc)
337 return rc;
30fc8d13 338
1bd047be 339 return crb_init(device, priv);
30fc8d13
JS
340}
341
342static int crb_acpi_remove(struct acpi_device *device)
343{
344 struct device *dev = &device->dev;
345 struct tpm_chip *chip = dev_get_drvdata(dev);
346
74d6b3ce
JS
347 if (chip->flags & TPM_CHIP_FLAG_TPM2)
348 tpm2_shutdown(chip, TPM2_SU_CLEAR);
349
99cda8cb
JS
350 tpm_chip_unregister(chip);
351
30fc8d13
JS
352 return 0;
353}
354
355static struct acpi_device_id crb_device_ids[] = {
356 {"MSFT0101", 0},
357 {"", 0},
358};
359MODULE_DEVICE_TABLE(acpi, crb_device_ids);
360
361static struct acpi_driver crb_acpi_driver = {
362 .name = "tpm_crb",
363 .ids = crb_device_ids,
364 .ops = {
365 .add = crb_acpi_add,
366 .remove = crb_acpi_remove,
367 },
368 .drv = {
369 .pm = &crb_pm,
370 },
371};
372
373module_acpi_driver(crb_acpi_driver);
374MODULE_AUTHOR("Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>");
375MODULE_DESCRIPTION("TPM2 Driver");
376MODULE_VERSION("0.1");
377MODULE_LICENSE("GPL");