2 * Copyright (C) 2014 Intel Corporation
5 * Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
7 * Maintained by: <tpmdd-devel@lists.sourceforge.net>
9 * This device driver implements the TPM interface as defined in
10 * the TCG CRB 2.0 TPM specification.
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
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>
25 #define ACPI_SIG_TPM2 "TPM2"
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
33 CRB_ACPI_START_REVISION_ID = 1,
34 CRB_ACPI_START_INDEX = 1,
37 enum crb_start_method {
38 CRB_SM_ACPI_START = 2,
40 CRB_SM_CRB_WITH_ACPI_START = 8,
44 struct acpi_table_header hdr;
52 CRB_CA_REQ_GO_IDLE = BIT(0),
53 CRB_CA_REQ_CMD_READY = BIT(1),
57 CRB_CA_STS_ERROR = BIT(0),
58 CRB_CA_STS_TPM_IDLE = BIT(1),
62 CRB_START_INVOKE = BIT(0),
66 CRB_CANCEL_INVOKE = BIT(0),
69 struct crb_control_area {
83 CRB_STS_COMPLETE = BIT(0),
87 CRB_FL_ACPI_START = BIT(0),
88 CRB_FL_CRB_START = BIT(1),
93 struct crb_control_area __iomem *cca;
98 #ifdef CONFIG_PM_SLEEP
99 static int crb_resume(struct device *dev)
102 struct tpm_chip *chip = dev_get_drvdata(dev);
104 rc = tpm2_shutdown(chip, TPM2_SU_STATE);
106 rc = tpm2_do_selftest(chip);
111 static SIMPLE_DEV_PM_OPS(crb_pm, tpm_pm_suspend, crb_resume);
114 static u8 crb_status(struct tpm_chip *chip)
116 struct crb_priv *priv = chip->vendor.priv;
119 if ((le32_to_cpu(ioread32(&priv->cca->start)) & CRB_START_INVOKE) !=
121 sts |= CRB_STS_COMPLETE;
126 static int crb_recv(struct tpm_chip *chip, u8 *buf, size_t count)
128 struct crb_priv *priv = chip->vendor.priv;
129 unsigned int expected;
135 if (le32_to_cpu(ioread32(&priv->cca->sts)) & CRB_CA_STS_ERROR)
138 memcpy_fromio(buf, priv->rsp, 6);
139 expected = be32_to_cpup((__be32 *) &buf[2]);
141 if (expected > count)
144 memcpy_fromio(&buf[6], &priv->rsp[6], expected - 6);
149 static int crb_do_acpi_start(struct tpm_chip *chip)
151 union acpi_object *obj;
154 obj = acpi_evaluate_dsm(chip->acpi_dev_handle,
156 CRB_ACPI_START_REVISION_ID,
157 CRB_ACPI_START_INDEX,
161 rc = obj->integer.value == 0 ? 0 : -ENXIO;
166 static int crb_send(struct tpm_chip *chip, u8 *buf, size_t len)
168 struct crb_priv *priv = chip->vendor.priv;
171 if (len > le32_to_cpu(ioread32(&priv->cca->cmd_size))) {
173 "invalid command count value %x %zx\n",
175 (size_t) le32_to_cpu(ioread32(&priv->cca->cmd_size)));
179 memcpy_toio(priv->cmd, buf, len);
181 /* Make sure that cmd is populated before issuing start. */
184 if (priv->flags & CRB_FL_CRB_START)
185 iowrite32(cpu_to_le32(CRB_START_INVOKE), &priv->cca->start);
187 if (priv->flags & CRB_FL_ACPI_START)
188 rc = crb_do_acpi_start(chip);
193 static void crb_cancel(struct tpm_chip *chip)
195 struct crb_priv *priv = chip->vendor.priv;
197 iowrite32(cpu_to_le32(CRB_CANCEL_INVOKE), &priv->cca->cancel);
199 /* Make sure that cmd is populated before issuing cancel. */
202 if ((priv->flags & CRB_FL_ACPI_START) && crb_do_acpi_start(chip))
203 dev_err(&chip->dev, "ACPI Start failed\n");
205 iowrite32(0, &priv->cca->cancel);
208 static bool crb_req_canceled(struct tpm_chip *chip, u8 status)
210 struct crb_priv *priv = chip->vendor.priv;
211 u32 cancel = le32_to_cpu(ioread32(&priv->cca->cancel));
213 return (cancel & CRB_CANCEL_INVOKE) == CRB_CANCEL_INVOKE;
216 static const struct tpm_class_ops tpm_crb = {
217 .status = crb_status,
220 .cancel = crb_cancel,
221 .req_canceled = crb_req_canceled,
222 .req_complete_mask = CRB_STS_COMPLETE,
223 .req_complete_val = CRB_STS_COMPLETE,
226 static int crb_acpi_add(struct acpi_device *device)
228 struct tpm_chip *chip;
229 struct acpi_tpm2 *buf;
230 struct crb_priv *priv;
231 struct device *dev = &device->dev;
237 chip = tpmm_chip_alloc(dev, &tpm_crb);
239 return PTR_ERR(chip);
241 chip->flags = TPM_CHIP_FLAG_TPM2;
243 status = acpi_get_table(ACPI_SIG_TPM2, 1,
244 (struct acpi_table_header **) &buf);
245 if (ACPI_FAILURE(status)) {
246 dev_err(dev, "failed to get TPM2 ACPI table\n");
250 if (buf->hdr.length < sizeof(struct acpi_tpm2)) {
251 dev_err(dev, "TPM2 ACPI table has wrong size");
255 priv = (struct crb_priv *) devm_kzalloc(dev, sizeof(struct crb_priv),
258 dev_err(dev, "failed to devm_kzalloc for private data\n");
262 sm = le32_to_cpu(buf->start_method);
264 /* The reason for the extra quirk is that the PTT in 4th Gen Core CPUs
265 * report only ACPI start but in practice seems to require both
266 * ACPI start and CRB start.
268 if (sm == CRB_SM_CRB || sm == CRB_SM_CRB_WITH_ACPI_START ||
269 !strcmp(acpi_device_hid(device), "MSFT0101"))
270 priv->flags |= CRB_FL_CRB_START;
272 if (sm == CRB_SM_ACPI_START || sm == CRB_SM_CRB_WITH_ACPI_START)
273 priv->flags |= CRB_FL_ACPI_START;
275 priv->cca = (struct crb_control_area __iomem *)
276 devm_ioremap_nocache(dev, buf->control_area_pa, 0x1000);
278 dev_err(dev, "ioremap of the control area failed\n");
282 memcpy_fromio(&pa, &priv->cca->cmd_pa, 8);
283 pa = le64_to_cpu(pa);
284 priv->cmd = devm_ioremap_nocache(dev, le64_to_cpu(pa),
285 ioread32(&priv->cca->cmd_size));
287 dev_err(dev, "ioremap of the command buffer failed\n");
291 memcpy_fromio(&pa, &priv->cca->rsp_pa, 8);
292 pa = le64_to_cpu(pa);
293 priv->rsp = devm_ioremap_nocache(dev, le64_to_cpu(pa),
294 ioread32(&priv->cca->rsp_size));
296 dev_err(dev, "ioremap of the response buffer failed\n");
300 chip->vendor.priv = priv;
302 /* Default timeouts and durations */
303 chip->vendor.timeout_a = msecs_to_jiffies(TPM2_TIMEOUT_A);
304 chip->vendor.timeout_b = msecs_to_jiffies(TPM2_TIMEOUT_B);
305 chip->vendor.timeout_c = msecs_to_jiffies(TPM2_TIMEOUT_C);
306 chip->vendor.timeout_d = msecs_to_jiffies(TPM2_TIMEOUT_D);
307 chip->vendor.duration[TPM_SHORT] =
308 msecs_to_jiffies(TPM2_DURATION_SHORT);
309 chip->vendor.duration[TPM_MEDIUM] =
310 msecs_to_jiffies(TPM2_DURATION_MEDIUM);
311 chip->vendor.duration[TPM_LONG] =
312 msecs_to_jiffies(TPM2_DURATION_LONG);
314 chip->acpi_dev_handle = device->handle;
316 rc = tpm2_do_selftest(chip);
320 return tpm_chip_register(chip);
323 static int crb_acpi_remove(struct acpi_device *device)
325 struct device *dev = &device->dev;
326 struct tpm_chip *chip = dev_get_drvdata(dev);
328 tpm_chip_unregister(chip);
332 static struct acpi_device_id crb_device_ids[] = {
336 MODULE_DEVICE_TABLE(acpi, crb_device_ids);
338 static struct acpi_driver crb_acpi_driver = {
340 .ids = crb_device_ids,
343 .remove = crb_acpi_remove,
350 module_acpi_driver(crb_acpi_driver);
351 MODULE_AUTHOR("Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>");
352 MODULE_DESCRIPTION("TPM2 Driver");
353 MODULE_VERSION("0.1");
354 MODULE_LICENSE("GPL");