blob: 7186c179d1162f5bc797a8f6fbe4fe1b0e920dec [file] [log] [blame]
Miquel Raynaleb469102018-05-15 11:57:21 +02001// SPDX-License-Identifier: GPL-2.0
2/*
3 * Author:
4 * Miquel Raynal <miquel.raynal@bootlin.com>
5 *
6 * Description:
7 * SPI-level driver for TCG/TIS TPM (trusted platform module).
8 * Specifications at www.trustedcomputinggroup.org
9 *
10 * This device driver implements the TPM interface as defined in
11 * the TCG SPI protocol stack version 2.0.
12 *
13 * It is based on the U-Boot driver tpm_tis_infineon_i2c.c.
14 */
15
16#include <common.h>
17#include <dm.h>
18#include <fdtdec.h>
19#include <log.h>
20#include <spi.h>
21#include <tpm-v2.h>
22#include <linux/errno.h>
23#include <linux/compiler.h>
24#include <linux/types.h>
25#include <linux/unaligned/be_byteshift.h>
Miquel Raynala174f002018-05-16 08:59:16 +020026#include <asm-generic/gpio.h>
Miquel Raynaleb469102018-05-15 11:57:21 +020027
28#include "tpm_tis.h"
29#include "tpm_internal.h"
30
31DECLARE_GLOBAL_DATA_PTR;
32
33#define TPM_ACCESS(l) (0x0000 | ((l) << 12))
34#define TPM_INT_ENABLE(l) (0x0008 | ((l) << 12))
35#define TPM_STS(l) (0x0018 | ((l) << 12))
36#define TPM_DATA_FIFO(l) (0x0024 | ((l) << 12))
37#define TPM_DID_VID(l) (0x0F00 | ((l) << 12))
38#define TPM_RID(l) (0x0F04 | ((l) << 12))
39
40#define MAX_SPI_FRAMESIZE 64
41
42/* Number of wait states to wait for */
43#define TPM_WAIT_STATES 100
44
45/**
46 * struct tpm_tis_chip_data - Non-discoverable TPM information
47 *
48 * @pcr_count: Number of PCR per bank
49 * @pcr_select_min: Size in octets of the pcrSelect array
50 */
51struct tpm_tis_chip_data {
52 unsigned int pcr_count;
53 unsigned int pcr_select_min;
54 unsigned int time_before_first_cmd_ms;
55};
56
57/**
58 * tpm_tis_spi_read() - Read from TPM register
59 *
60 * @addr: register address to read from
61 * @buffer: provided by caller
62 * @len: number of bytes to read
63 *
64 * Read len bytes from TPM register and put them into
65 * buffer (little-endian format, i.e. first byte is put into buffer[0]).
66 *
67 * NOTE: TPM is big-endian for multi-byte values. Multi-byte
68 * values have to be swapped.
69 *
70 * @return -EIO on error, 0 on success.
71 */
72static int tpm_tis_spi_xfer(struct udevice *dev, u32 addr, const u8 *out,
73 u8 *in, u16 len)
74{
75 struct spi_slave *slave = dev_get_parent_priv(dev);
76 int transfer_len, ret;
77 u8 tx_buf[MAX_SPI_FRAMESIZE];
78 u8 rx_buf[MAX_SPI_FRAMESIZE];
79
80 if (in && out) {
81 log(LOGC_NONE, LOGL_ERR, "%s: can't do full duplex\n",
82 __func__);
83 return -EINVAL;
84 }
85
86 ret = spi_claim_bus(slave);
87 if (ret < 0) {
88 log(LOGC_NONE, LOGL_ERR, "%s: could not claim bus\n", __func__);
89 return ret;
90 }
91
92 while (len) {
93 /* Request */
94 transfer_len = min_t(u16, len, MAX_SPI_FRAMESIZE);
95 tx_buf[0] = (in ? BIT(7) : 0) | (transfer_len - 1);
96 tx_buf[1] = 0xD4;
97 tx_buf[2] = addr >> 8;
98 tx_buf[3] = addr;
99
100 ret = spi_xfer(slave, 4 * 8, tx_buf, rx_buf, SPI_XFER_BEGIN);
101 if (ret < 0) {
102 log(LOGC_NONE, LOGL_ERR,
103 "%s: spi request transfer failed (err: %d)\n",
104 __func__, ret);
105 goto release_bus;
106 }
107
108 /* Wait state */
109 if (!(rx_buf[3] & 0x1)) {
110 int i;
111
112 for (i = 0; i < TPM_WAIT_STATES; i++) {
113 ret = spi_xfer(slave, 1 * 8, NULL, rx_buf, 0);
114 if (ret) {
115 log(LOGC_NONE, LOGL_ERR,
116 "%s: wait state failed: %d\n",
117 __func__, ret);
118 goto release_bus;
119 }
120
121 if (rx_buf[0] & 0x1)
122 break;
123 }
124
125 if (i == TPM_WAIT_STATES) {
126 log(LOGC_NONE, LOGL_ERR,
127 "%s: timeout on wait state\n", __func__);
128 ret = -ETIMEDOUT;
129 goto release_bus;
130 }
131 }
132
133 /* Read/Write */
134 if (out) {
135 memcpy(tx_buf, out, transfer_len);
136 out += transfer_len;
137 }
138
139 ret = spi_xfer(slave, transfer_len * 8,
140 out ? tx_buf : NULL,
141 in ? rx_buf : NULL,
142 SPI_XFER_END);
143 if (ret) {
144 log(LOGC_NONE, LOGL_ERR,
145 "%s: spi read transfer failed (err: %d)\n",
146 __func__, ret);
147 goto release_bus;
148 }
149
150 if (in) {
151 memcpy(in, rx_buf, transfer_len);
152 in += transfer_len;
153 }
154
155 len -= transfer_len;
156 }
157
158release_bus:
159 /* If an error occurred, release the chip by deasserting the CS */
160 if (ret < 0)
161 spi_xfer(slave, 0, NULL, NULL, SPI_XFER_END);
162
163 spi_release_bus(slave);
164
165 return ret;
166}
167
168static int tpm_tis_spi_read(struct udevice *dev, u16 addr, u8 *in, u16 len)
169{
170 return tpm_tis_spi_xfer(dev, addr, NULL, in, len);
171}
172
173static int tpm_tis_spi_read32(struct udevice *dev, u32 addr, u32 *result)
174{
175 __le32 result_le;
176 int ret;
177
178 ret = tpm_tis_spi_read(dev, addr, (u8 *)&result_le, sizeof(u32));
179 if (!ret)
180 *result = le32_to_cpu(result_le);
181
182 return ret;
183}
184
185static int tpm_tis_spi_write(struct udevice *dev, u16 addr, const u8 *out,
186 u16 len)
187{
188 return tpm_tis_spi_xfer(dev, addr, out, NULL, len);
189}
190
191static int tpm_tis_spi_check_locality(struct udevice *dev, int loc)
192{
193 const u8 mask = TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID;
194 struct tpm_chip *chip = dev_get_priv(dev);
195 u8 buf;
196 int ret;
197
198 ret = tpm_tis_spi_read(dev, TPM_ACCESS(loc), &buf, 1);
199 if (ret)
200 return ret;
201
202 if ((buf & mask) == mask) {
203 chip->locality = loc;
204 return 0;
205 }
206
207 return -ENOENT;
208}
209
210static void tpm_tis_spi_release_locality(struct udevice *dev, int loc,
211 bool force)
212{
213 const u8 mask = TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID;
214 u8 buf;
215
216 if (tpm_tis_spi_read(dev, TPM_ACCESS(loc), &buf, 1) < 0)
217 return;
218
219 if (force || (buf & mask) == mask) {
220 buf = TPM_ACCESS_ACTIVE_LOCALITY;
221 tpm_tis_spi_write(dev, TPM_ACCESS(loc), &buf, 1);
222 }
223}
224
225static int tpm_tis_spi_request_locality(struct udevice *dev, int loc)
226{
227 struct tpm_chip *chip = dev_get_priv(dev);
228 unsigned long start, stop;
229 u8 buf = TPM_ACCESS_REQUEST_USE;
230 int ret;
231
232 ret = tpm_tis_spi_check_locality(dev, loc);
233 if (!ret)
234 return 0;
235
236 if (ret != -ENOENT) {
237 log(LOGC_NONE, LOGL_ERR, "%s: Failed to get locality: %d\n",
238 __func__, ret);
239 return ret;
240 }
241
242 ret = tpm_tis_spi_write(dev, TPM_ACCESS(loc), &buf, 1);
243 if (ret) {
244 log(LOGC_NONE, LOGL_ERR, "%s: Failed to write to TPM: %d\n",
245 __func__, ret);
246 return ret;
247 }
248
249 start = get_timer(0);
250 stop = chip->timeout_a;
251 do {
252 ret = tpm_tis_spi_check_locality(dev, loc);
253 if (!ret)
254 return 0;
255
256 if (ret != -ENOENT) {
257 log(LOGC_NONE, LOGL_ERR,
258 "%s: Failed to get locality: %d\n", __func__, ret);
259 return ret;
260 }
261
262 mdelay(TPM_TIMEOUT_MS);
263 } while (get_timer(start) < stop);
264
265 log(LOGC_NONE, LOGL_ERR, "%s: Timeout getting locality: %d\n", __func__,
266 ret);
267
268 return ret;
269}
270
271static u8 tpm_tis_spi_status(struct udevice *dev, u8 *status)
272{
273 struct tpm_chip *chip = dev_get_priv(dev);
274
275 return tpm_tis_spi_read(dev, TPM_STS(chip->locality), status, 1);
276}
277
278static int tpm_tis_spi_wait_for_stat(struct udevice *dev, u8 mask,
279 unsigned long timeout, u8 *status)
280{
281 unsigned long start = get_timer(0);
282 unsigned long stop = timeout;
283 int ret;
284
285 do {
286 mdelay(TPM_TIMEOUT_MS);
287 ret = tpm_tis_spi_status(dev, status);
288 if (ret)
289 return ret;
290
291 if ((*status & mask) == mask)
292 return 0;
293 } while (get_timer(start) < stop);
294
295 return -ETIMEDOUT;
296}
297
Roman Kapl27eb1772019-05-16 18:32:48 +0200298static u8 tpm_tis_spi_valid_status(struct udevice *dev, u8 *status)
299{
300 struct tpm_chip *chip = dev_get_priv(dev);
301
302 return tpm_tis_spi_wait_for_stat(dev, TPM_STS_VALID,
303 chip->timeout_c, status);
304}
305
Miquel Raynaleb469102018-05-15 11:57:21 +0200306static int tpm_tis_spi_get_burstcount(struct udevice *dev)
307{
308 struct tpm_chip *chip = dev_get_priv(dev);
309 unsigned long start, stop;
310 u32 burstcount, ret;
311
312 /* wait for burstcount */
313 start = get_timer(0);
314 stop = chip->timeout_d;
315 do {
316 ret = tpm_tis_spi_read32(dev, TPM_STS(chip->locality),
317 &burstcount);
318 if (ret)
319 return -EBUSY;
320
321 burstcount = (burstcount >> 8) & 0xFFFF;
322 if (burstcount)
323 return burstcount;
324
325 mdelay(TPM_TIMEOUT_MS);
326 } while (get_timer(start) < stop);
327
328 return -EBUSY;
329}
330
331static int tpm_tis_spi_cancel(struct udevice *dev)
332{
333 struct tpm_chip *chip = dev_get_priv(dev);
334 u8 data = TPM_STS_COMMAND_READY;
335
336 return tpm_tis_spi_write(dev, TPM_STS(chip->locality), &data, 1);
337}
338
339static int tpm_tis_spi_recv_data(struct udevice *dev, u8 *buf, size_t count)
340{
341 struct tpm_chip *chip = dev_get_priv(dev);
342 int size = 0, burstcnt, len, ret;
343 u8 status;
344
345 while (size < count &&
346 tpm_tis_spi_wait_for_stat(dev,
347 TPM_STS_DATA_AVAIL | TPM_STS_VALID,
348 chip->timeout_c, &status) == 0) {
349 burstcnt = tpm_tis_spi_get_burstcount(dev);
350 if (burstcnt < 0)
351 return burstcnt;
352
353 len = min_t(int, burstcnt, count - size);
354 ret = tpm_tis_spi_read(dev, TPM_DATA_FIFO(chip->locality),
355 buf + size, len);
356 if (ret < 0)
357 return ret;
358
359 size += len;
360 }
361
362 return size;
363}
364
365static int tpm_tis_spi_recv(struct udevice *dev, u8 *buf, size_t count)
366{
367 struct tpm_chip *chip = dev_get_priv(dev);
368 int size, expected;
369
370 if (!chip)
371 return -ENODEV;
372
373 if (count < TPM_HEADER_SIZE) {
374 size = -EIO;
375 goto out;
376 }
377
378 size = tpm_tis_spi_recv_data(dev, buf, TPM_HEADER_SIZE);
379 if (size < TPM_HEADER_SIZE) {
380 log(LOGC_NONE, LOGL_ERR, "TPM error, unable to read header\n");
381 goto out;
382 }
383
384 expected = get_unaligned_be32(buf + 2);
385 if (expected > count) {
386 size = -EIO;
387 goto out;
388 }
389
390 size += tpm_tis_spi_recv_data(dev, &buf[TPM_HEADER_SIZE],
391 expected - TPM_HEADER_SIZE);
392 if (size < expected) {
393 log(LOGC_NONE, LOGL_ERR,
394 "TPM error, unable to read remaining bytes of result\n");
395 size = -EIO;
396 goto out;
397 }
398
399out:
400 tpm_tis_spi_cancel(dev);
401 tpm_tis_spi_release_locality(dev, chip->locality, false);
402
403 return size;
404}
405
406static int tpm_tis_spi_send(struct udevice *dev, const u8 *buf, size_t len)
407{
408 struct tpm_chip *chip = dev_get_priv(dev);
409 u32 i, size;
410 u8 status;
411 int burstcnt, ret;
412 u8 data;
413
414 if (!chip)
415 return -ENODEV;
416
417 if (len > TPM_DEV_BUFSIZE)
418 return -E2BIG; /* Command is too long for our tpm, sorry */
419
420 ret = tpm_tis_spi_request_locality(dev, 0);
421 if (ret < 0)
422 return -EBUSY;
423
424 /*
425 * Check if the TPM is ready. If not, if not, cancel the pending command
426 * and poll on the status to be finally ready.
427 */
428 ret = tpm_tis_spi_status(dev, &status);
429 if (ret)
430 return ret;
431
432 if (!(status & TPM_STS_COMMAND_READY)) {
433 /* Force the transition, usually this will be done at startup */
434 ret = tpm_tis_spi_cancel(dev);
435 if (ret) {
436 log(LOGC_NONE, LOGL_ERR,
437 "%s: Could not cancel previous operation\n",
438 __func__);
439 goto out_err;
440 }
441
442 ret = tpm_tis_spi_wait_for_stat(dev, TPM_STS_COMMAND_READY,
443 chip->timeout_b, &status);
444 if (ret < 0 || !(status & TPM_STS_COMMAND_READY)) {
445 log(LOGC_NONE, LOGL_ERR,
446 "status %d after wait for stat returned %d\n",
447 status, ret);
448 goto out_err;
449 }
450 }
451
452 for (i = 0; i < len - 1;) {
453 burstcnt = tpm_tis_spi_get_burstcount(dev);
454 if (burstcnt < 0)
455 return burstcnt;
456
457 size = min_t(int, len - i - 1, burstcnt);
458 ret = tpm_tis_spi_write(dev, TPM_DATA_FIFO(chip->locality),
459 buf + i, size);
460 if (ret < 0)
461 goto out_err;
462
463 i += size;
464 }
465
Roman Kapl27eb1772019-05-16 18:32:48 +0200466 ret = tpm_tis_spi_valid_status(dev, &status);
Miquel Raynaleb469102018-05-15 11:57:21 +0200467 if (ret)
468 goto out_err;
469
470 if ((status & TPM_STS_DATA_EXPECT) == 0) {
471 ret = -EIO;
472 goto out_err;
473 }
474
475 ret = tpm_tis_spi_write(dev, TPM_DATA_FIFO(chip->locality),
476 buf + len - 1, 1);
477 if (ret)
478 goto out_err;
479
Roman Kapl27eb1772019-05-16 18:32:48 +0200480 ret = tpm_tis_spi_valid_status(dev, &status);
Miquel Raynaleb469102018-05-15 11:57:21 +0200481 if (ret)
482 goto out_err;
483
484 if ((status & TPM_STS_DATA_EXPECT) != 0) {
485 ret = -EIO;
486 goto out_err;
487 }
488
489 data = TPM_STS_GO;
490 ret = tpm_tis_spi_write(dev, TPM_STS(chip->locality), &data, 1);
491 if (ret)
492 goto out_err;
493
494 return len;
495
496out_err:
497 tpm_tis_spi_cancel(dev);
498 tpm_tis_spi_release_locality(dev, chip->locality, false);
499
500 return ret;
501}
502
503static int tpm_tis_spi_cleanup(struct udevice *dev)
504{
505 struct tpm_chip *chip = dev_get_priv(dev);
506
507 tpm_tis_spi_cancel(dev);
508 /*
509 * The TPM needs some time to clean up here,
510 * so we sleep rather than keeping the bus busy
511 */
512 mdelay(2);
513 tpm_tis_spi_release_locality(dev, chip->locality, false);
514
515 return 0;
516}
517
518static int tpm_tis_spi_open(struct udevice *dev)
519{
520 struct tpm_chip *chip = dev_get_priv(dev);
Miquel Raynal2a2096e2018-07-19 22:35:09 +0200521 struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
Miquel Raynaleb469102018-05-15 11:57:21 +0200522
523 if (chip->is_open)
524 return -EBUSY;
525
526 chip->is_open = 1;
527
528 return 0;
529}
530
531static int tpm_tis_spi_close(struct udevice *dev)
532{
533 struct tpm_chip *chip = dev_get_priv(dev);
534
535 if (chip->is_open) {
536 tpm_tis_spi_release_locality(dev, chip->locality, true);
537 chip->is_open = 0;
538 }
539
540 return 0;
541}
542
543static int tpm_tis_get_desc(struct udevice *dev, char *buf, int size)
544{
545 struct tpm_chip *chip = dev_get_priv(dev);
546
547 if (size < 80)
548 return -ENOSPC;
549
550 return snprintf(buf, size,
551 "%s v2.0: VendorID 0x%04x, DeviceID 0x%04x, RevisionID 0x%02x [%s]",
552 dev->name, chip->vend_dev & 0xFFFF,
553 chip->vend_dev >> 16, chip->rid,
554 (chip->is_open ? "open" : "closed"));
555}
556
557static int tpm_tis_wait_init(struct udevice *dev, int loc)
558{
559 struct tpm_chip *chip = dev_get_priv(dev);
560 unsigned long start, stop;
561 u8 status;
562 int ret;
563
564 start = get_timer(0);
565 stop = chip->timeout_b;
566 do {
567 mdelay(TPM_TIMEOUT_MS);
568
569 ret = tpm_tis_spi_read(dev, TPM_ACCESS(loc), &status, 1);
570 if (ret)
571 break;
572
573 if (status & TPM_ACCESS_VALID)
574 return 0;
575 } while (get_timer(start) < stop);
576
577 return -EIO;
578}
579
580static int tpm_tis_spi_probe(struct udevice *dev)
581{
582 struct tpm_tis_chip_data *drv_data = (void *)dev_get_driver_data(dev);
583 struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
584 struct tpm_chip *chip = dev_get_priv(dev);
585 int ret;
586
Miquel Raynal2a2096e2018-07-19 22:35:09 +0200587 /* Use the TPM v2 stack */
588 priv->version = TPM_V2;
589
Miquel Raynala174f002018-05-16 08:59:16 +0200590 if (IS_ENABLED(CONFIG_DM_GPIO)) {
591 struct gpio_desc reset_gpio;
592
593 ret = gpio_request_by_name(dev, "gpio-reset", 0,
594 &reset_gpio, GPIOD_IS_OUT);
595 if (ret) {
596 log(LOGC_NONE, LOGL_NOTICE, "%s: missing reset GPIO\n",
597 __func__);
598 } else {
599 dm_gpio_set_value(&reset_gpio, 0);
600 mdelay(1);
601 dm_gpio_set_value(&reset_gpio, 1);
602 }
603 }
604
Miquel Raynaleb469102018-05-15 11:57:21 +0200605 /* Ensure a minimum amount of time elapsed since reset of the TPM */
606 mdelay(drv_data->time_before_first_cmd_ms);
607
608 chip->locality = 0;
609 chip->timeout_a = TIS_SHORT_TIMEOUT_MS;
610 chip->timeout_b = TIS_LONG_TIMEOUT_MS;
611 chip->timeout_c = TIS_SHORT_TIMEOUT_MS;
612 chip->timeout_d = TIS_SHORT_TIMEOUT_MS;
613 priv->pcr_count = drv_data->pcr_count;
614 priv->pcr_select_min = drv_data->pcr_select_min;
615
616 ret = tpm_tis_wait_init(dev, chip->locality);
617 if (ret) {
618 log(LOGC_DM, LOGL_ERR, "%s: no device found\n", __func__);
619 return ret;
620 }
621
622 ret = tpm_tis_spi_request_locality(dev, chip->locality);
623 if (ret) {
624 log(LOGC_NONE, LOGL_ERR, "%s: could not request locality %d\n",
625 __func__, chip->locality);
626 return ret;
627 }
628
629 ret = tpm_tis_spi_read32(dev, TPM_DID_VID(chip->locality),
630 &chip->vend_dev);
631 if (ret) {
632 log(LOGC_NONE, LOGL_ERR,
633 "%s: could not retrieve VendorID/DeviceID\n", __func__);
634 return ret;
635 }
636
637 ret = tpm_tis_spi_read(dev, TPM_RID(chip->locality), &chip->rid, 1);
638 if (ret) {
639 log(LOGC_NONE, LOGL_ERR, "%s: could not retrieve RevisionID\n",
640 __func__);
641 return ret;
642 }
643
644 log(LOGC_NONE, LOGL_ERR,
645 "SPI TPMv2.0 found (vid:%04x, did:%04x, rid:%02x)\n",
646 chip->vend_dev & 0xFFFF, chip->vend_dev >> 16, chip->rid);
647
648 return 0;
649}
650
651static int tpm_tis_spi_remove(struct udevice *dev)
652{
653 struct tpm_chip *chip = dev_get_priv(dev);
654
655 tpm_tis_spi_release_locality(dev, chip->locality, true);
656
657 return 0;
658}
659
660static const struct tpm_ops tpm_tis_spi_ops = {
661 .open = tpm_tis_spi_open,
662 .close = tpm_tis_spi_close,
663 .get_desc = tpm_tis_get_desc,
664 .send = tpm_tis_spi_send,
665 .recv = tpm_tis_spi_recv,
666 .cleanup = tpm_tis_spi_cleanup,
667};
668
669static const struct tpm_tis_chip_data tpm_tis_std_chip_data = {
670 .pcr_count = 24,
671 .pcr_select_min = 3,
672 .time_before_first_cmd_ms = 30,
673};
674
675static const struct udevice_id tpm_tis_spi_ids[] = {
676 {
677 .compatible = "tis,tpm2-spi",
678 .data = (ulong)&tpm_tis_std_chip_data,
679 },
680 { }
681};
682
683U_BOOT_DRIVER(tpm_tis_spi) = {
684 .name = "tpm_tis_spi",
685 .id = UCLASS_TPM,
686 .of_match = tpm_tis_spi_ids,
687 .ops = &tpm_tis_spi_ops,
688 .probe = tpm_tis_spi_probe,
689 .remove = tpm_tis_spi_remove,
690 .priv_auto_alloc_size = sizeof(struct tpm_chip),
691};