ASoC: Use card field to indicate whether a component is bound
[linux-2.6-block.git] / drivers / char / tpm / tpm_crb.c
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
27 static 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
32 enum crb_defaults {
33         CRB_ACPI_START_REVISION_ID = 1,
34         CRB_ACPI_START_INDEX = 1,
35 };
36
37 enum crb_start_method {
38         CRB_SM_ACPI_START = 2,
39         CRB_SM_CRB = 7,
40         CRB_SM_CRB_WITH_ACPI_START = 8,
41 };
42
43 struct acpi_tpm2 {
44         struct acpi_table_header hdr;
45         u16 platform_class;
46         u16 reserved;
47         u64 control_area_pa;
48         u32 start_method;
49 } __packed;
50
51 enum crb_ca_request {
52         CRB_CA_REQ_GO_IDLE      = BIT(0),
53         CRB_CA_REQ_CMD_READY    = BIT(1),
54 };
55
56 enum crb_ca_status {
57         CRB_CA_STS_ERROR        = BIT(0),
58         CRB_CA_STS_TPM_IDLE     = BIT(1),
59 };
60
61 enum crb_start {
62         CRB_START_INVOKE        = BIT(0),
63 };
64
65 enum crb_cancel {
66         CRB_CANCEL_INVOKE       = BIT(0),
67 };
68
69 struct crb_control_area {
70         u32 req;
71         u32 sts;
72         u32 cancel;
73         u32 start;
74         u32 int_enable;
75         u32 int_sts;
76         u32 cmd_size;
77         u64 cmd_pa;
78         u32 rsp_size;
79         u64 rsp_pa;
80 } __packed;
81
82 enum crb_status {
83         CRB_STS_COMPLETE        = BIT(0),
84 };
85
86 enum crb_flags {
87         CRB_FL_ACPI_START       = BIT(0),
88         CRB_FL_CRB_START        = BIT(1),
89 };
90
91 struct crb_priv {
92         unsigned int flags;
93         struct crb_control_area __iomem *cca;
94         u8 __iomem *cmd;
95         u8 __iomem *rsp;
96 };
97
98 static SIMPLE_DEV_PM_OPS(crb_pm, tpm_pm_suspend, tpm_pm_resume);
99
100 static u8 crb_status(struct tpm_chip *chip)
101 {
102         struct crb_priv *priv = chip->vendor.priv;
103         u8 sts = 0;
104
105         if ((le32_to_cpu(ioread32(&priv->cca->start)) & CRB_START_INVOKE) !=
106             CRB_START_INVOKE)
107                 sts |= CRB_STS_COMPLETE;
108
109         return sts;
110 }
111
112 static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count)
113 {
114         struct crb_priv *priv = chip->vendor.priv;
115         unsigned int expected;
116
117         /* sanity check */
118         if (count < 6)
119                 return -EIO;
120
121         if (le32_to_cpu(ioread32(&priv->cca->sts)) & CRB_CA_STS_ERROR)
122                 return -EIO;
123
124         memcpy_fromio(buf, priv->rsp, 6);
125         expected = be32_to_cpup((__be32 *) &buf[2]);
126
127         if (expected > count)
128                 return -EIO;
129
130         memcpy_fromio(&buf[6], &priv->rsp[6], expected - 6);
131
132         return expected;
133 }
134
135 static int crb_do_acpi_start(struct tpm_chip *chip)
136 {
137         union acpi_object *obj;
138         int rc;
139
140         obj = acpi_evaluate_dsm(chip->acpi_dev_handle,
141                                 CRB_ACPI_START_UUID,
142                                 CRB_ACPI_START_REVISION_ID,
143                                 CRB_ACPI_START_INDEX,
144                                 NULL);
145         if (!obj)
146                 return -ENXIO;
147         rc = obj->integer.value == 0 ? 0 : -ENXIO;
148         ACPI_FREE(obj);
149         return rc;
150 }
151
152 static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
153 {
154         struct crb_priv *priv = chip->vendor.priv;
155         int rc = 0;
156
157         if (len > le32_to_cpu(ioread32(&priv->cca->cmd_size))) {
158                 dev_err(&chip->dev,
159                         "invalid command count value %x %zx\n",
160                         (unsigned int) len,
161                         (size_t) le32_to_cpu(ioread32(&priv->cca->cmd_size)));
162                 return -E2BIG;
163         }
164
165         memcpy_toio(priv->cmd, buf, len);
166
167         /* Make sure that cmd is populated before issuing start. */
168         wmb();
169
170         if (priv->flags & CRB_FL_CRB_START)
171                 iowrite32(cpu_to_le32(CRB_START_INVOKE), &priv->cca->start);
172
173         if (priv->flags & CRB_FL_ACPI_START)
174                 rc = crb_do_acpi_start(chip);
175
176         return rc;
177 }
178
179 static void crb_cancel(struct tpm_chip *chip)
180 {
181         struct crb_priv *priv = chip->vendor.priv;
182
183         iowrite32(cpu_to_le32(CRB_CANCEL_INVOKE), &priv->cca->cancel);
184
185         /* Make sure that cmd is populated before issuing cancel. */
186         wmb();
187
188         if ((priv->flags & CRB_FL_ACPI_START) && crb_do_acpi_start(chip))
189                 dev_err(&chip->dev, "ACPI Start failed\n");
190
191         iowrite32(0, &priv->cca->cancel);
192 }
193
194 static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
195 {
196         struct crb_priv *priv = chip->vendor.priv;
197         u32 cancel = le32_to_cpu(ioread32(&priv->cca->cancel));
198
199         return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE;
200 }
201
202 static const struct tpm_class_ops tpm_crb = {
203         .status = crb_status,
204         .recv = crb_recv,
205         .send = crb_send,
206         .cancel = crb_cancel,
207         .req_canceled = crb_req_canceled,
208         .req_complete_mask = CRB_STS_COMPLETE,
209         .req_complete_val = CRB_STS_COMPLETE,
210 };
211
212 static int crb_acpi_add(struct acpi_device *device)
213 {
214         struct tpm_chip *chip;
215         struct acpi_tpm2 *buf;
216         struct crb_priv *priv;
217         struct device *dev = &device->dev;
218         acpi_status status;
219         u32 sm;
220         u64 pa;
221         int rc;
222
223         chip = tpmm_chip_alloc(dev, &tpm_crb);
224         if (IS_ERR(chip))
225                 return PTR_ERR(chip);
226
227         chip->flags = TPM_CHIP_FLAG_TPM2;
228
229         status = acpi_get_table(ACPI_SIG_TPM2, 1,
230                                 (struct acpi_table_header **) &buf);
231         if (ACPI_FAILURE(status)) {
232                 dev_err(dev, "failed to get TPM2 ACPI table\n");
233                 return -ENODEV;
234         }
235
236         if (buf->hdr.length < sizeof(struct acpi_tpm2)) {
237                 dev_err(dev, "TPM2 ACPI table has wrong size");
238                 return -EINVAL;
239         }
240
241         priv = (struct crb_priv *) devm_kzalloc(dev, sizeof(struct crb_priv),
242                                                 GFP_KERNEL);
243         if (!priv) {
244                 dev_err(dev, "failed to devm_kzalloc for private data\n");
245                 return -ENOMEM;
246         }
247
248         sm = le32_to_cpu(buf->start_method);
249
250         /* The reason for the extra quirk is that the PTT in 4th Gen Core CPUs
251          * report only ACPI start but in practice seems to require both
252          * ACPI start and CRB start.
253          */
254         if (sm == CRB_SM_CRB || sm == CRB_SM_CRB_WITH_ACPI_START ||
255             !strcmp(acpi_device_hid(device), "MSFT0101"))
256                 priv->flags |= CRB_FL_CRB_START;
257
258         if (sm == CRB_SM_ACPI_START || sm == CRB_SM_CRB_WITH_ACPI_START)
259                 priv->flags |= CRB_FL_ACPI_START;
260
261         priv->cca = (struct crb_control_area __iomem *)
262                 devm_ioremap_nocache(dev, buf->control_area_pa, 0x1000);
263         if (!priv->cca) {
264                 dev_err(dev, "ioremap of the control area failed\n");
265                 return -ENOMEM;
266         }
267
268         memcpy_fromio(&pa, &priv->cca->cmd_pa, 8);
269         pa = le64_to_cpu(pa);
270         priv->cmd = devm_ioremap_nocache(dev, pa,
271                                          ioread32(&priv->cca->cmd_size));
272         if (!priv->cmd) {
273                 dev_err(dev, "ioremap of the command buffer failed\n");
274                 return -ENOMEM;
275         }
276
277         memcpy_fromio(&pa, &priv->cca->rsp_pa, 8);
278         pa = le64_to_cpu(pa);
279         priv->rsp = devm_ioremap_nocache(dev, pa,
280                                          ioread32(&priv->cca->rsp_size));
281         if (!priv->rsp) {
282                 dev_err(dev, "ioremap of the response buffer failed\n");
283                 return -ENOMEM;
284         }
285
286         chip->vendor.priv = priv;
287
288         /* Default timeouts and durations */
289         chip->vendor.timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
290         chip->vendor.timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
291         chip->vendor.timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
292         chip->vendor.timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
293         chip->vendor.duration[TPM_SHORT] =
294                 msecs_to_jiffies(TPM2_DURATION_SHORT);
295         chip->vendor.duration[TPM_MEDIUM] =
296                 msecs_to_jiffies(TPM2_DURATION_MEDIUM);
297         chip->vendor.duration[TPM_LONG] =
298                 msecs_to_jiffies(TPM2_DURATION_LONG);
299
300         chip->acpi_dev_handle = device->handle;
301
302         rc = tpm2_do_selftest(chip);
303         if (rc)
304                 return rc;
305
306         return tpm_chip_register(chip);
307 }
308
309 static int crb_acpi_remove(struct acpi_device *device)
310 {
311         struct device *dev = &device->dev;
312         struct tpm_chip *chip = dev_get_drvdata(dev);
313
314         tpm_chip_unregister(chip);
315
316         if (chip->flags & TPM_CHIP_FLAG_TPM2)
317                 tpm2_shutdown(chip, TPM2_SU_CLEAR);
318
319         return 0;
320 }
321
322 static struct acpi_device_id crb_device_ids[] = {
323         {"MSFT0101", 0},
324         {"", 0},
325 };
326 MODULE_DEVICE_TABLE(acpi, crb_device_ids);
327
328 static struct acpi_driver crb_acpi_driver = {
329         .name = "tpm_crb",
330         .ids = crb_device_ids,
331         .ops = {
332                 .add = crb_acpi_add,
333                 .remove = crb_acpi_remove,
334         },
335         .drv = {
336                 .pm = &crb_pm,
337         },
338 };
339
340 module_acpi_driver(crb_acpi_driver);
341 MODULE_AUTHOR("Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>");
342 MODULE_DESCRIPTION("TPM2 Driver");
343 MODULE_VERSION("0.1");
344 MODULE_LICENSE("GPL");