1 // SPDX-License-Identifier: GPL-2.0
4 * Miquel Raynal <miquel.raynal@bootlin.com>
7 * SPI-level driver for TCG/TIS TPM (trusted platform module).
8 * Specifications at www.trustedcomputinggroup.org
10 * This device driver implements the TPM interface as defined in
11 * the TCG SPI protocol stack version 2.0.
13 * It is based on the U-Boot driver tpm_tis_infineon_i2c.c.
22 #include <linux/errno.h>
23 #include <linux/compiler.h>
24 #include <linux/types.h>
25 #include <linux/unaligned/be_byteshift.h>
26 #include <asm-generic/gpio.h>
29 #include "tpm_internal.h"
31 DECLARE_GLOBAL_DATA_PTR;
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))
40 #define MAX_SPI_FRAMESIZE 64
42 /* Number of wait states to wait for */
43 #define TPM_WAIT_STATES 100
46 * struct tpm_tis_chip_data - Non-discoverable TPM information
48 * @pcr_count: Number of PCR per bank
49 * @pcr_select_min: Size in octets of the pcrSelect array
51 struct tpm_tis_chip_data {
52 unsigned int pcr_count;
53 unsigned int pcr_select_min;
54 unsigned int time_before_first_cmd_ms;
58 * tpm_tis_spi_read() - Read from TPM register
60 * @addr: register address to read from
61 * @buffer: provided by caller
62 * @len: number of bytes to read
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]).
67 * NOTE: TPM is big-endian for multi-byte values. Multi-byte
68 * values have to be swapped.
70 * @return -EIO on error, 0 on success.
72 static int tpm_tis_spi_xfer(struct udevice *dev, u32 addr, const u8 *out,
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];
81 log(LOGC_NONE, LOGL_ERR, "%s: can't do full duplex\n",
86 ret = spi_claim_bus(slave);
88 log(LOGC_NONE, LOGL_ERR, "%s: could not claim bus\n", __func__);
94 transfer_len = min_t(u16, len, MAX_SPI_FRAMESIZE);
95 tx_buf[0] = (in ? BIT(7) : 0) | (transfer_len - 1);
97 tx_buf[2] = addr >> 8;
100 ret = spi_xfer(slave, 4 * 8, tx_buf, rx_buf, SPI_XFER_BEGIN);
102 log(LOGC_NONE, LOGL_ERR,
103 "%s: spi request transfer failed (err: %d)\n",
109 if (!(rx_buf[3] & 0x1)) {
112 for (i = 0; i < TPM_WAIT_STATES; i++) {
113 ret = spi_xfer(slave, 1 * 8, NULL, rx_buf, 0);
115 log(LOGC_NONE, LOGL_ERR,
116 "%s: wait state failed: %d\n",
125 if (i == TPM_WAIT_STATES) {
126 log(LOGC_NONE, LOGL_ERR,
127 "%s: timeout on wait state\n", __func__);
135 memcpy(tx_buf, out, transfer_len);
139 ret = spi_xfer(slave, transfer_len * 8,
144 log(LOGC_NONE, LOGL_ERR,
145 "%s: spi read transfer failed (err: %d)\n",
151 memcpy(in, rx_buf, transfer_len);
159 /* If an error occurred, release the chip by deasserting the CS */
161 spi_xfer(slave, 0, NULL, NULL, SPI_XFER_END);
163 spi_release_bus(slave);
168 static int tpm_tis_spi_read(struct udevice *dev, u16 addr, u8 *in, u16 len)
170 return tpm_tis_spi_xfer(dev, addr, NULL, in, len);
173 static int tpm_tis_spi_read32(struct udevice *dev, u32 addr, u32 *result)
178 ret = tpm_tis_spi_read(dev, addr, (u8 *)&result_le, sizeof(u32));
180 *result = le32_to_cpu(result_le);
185 static int tpm_tis_spi_write(struct udevice *dev, u16 addr, const u8 *out,
188 return tpm_tis_spi_xfer(dev, addr, out, NULL, len);
191 static int tpm_tis_spi_check_locality(struct udevice *dev, int loc)
193 const u8 mask = TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID;
194 struct tpm_chip *chip = dev_get_priv(dev);
198 ret = tpm_tis_spi_read(dev, TPM_ACCESS(loc), &buf, 1);
202 if ((buf & mask) == mask) {
203 chip->locality = loc;
210 static void tpm_tis_spi_release_locality(struct udevice *dev, int loc,
213 const u8 mask = TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID;
216 if (tpm_tis_spi_read(dev, TPM_ACCESS(loc), &buf, 1) < 0)
219 if (force || (buf & mask) == mask) {
220 buf = TPM_ACCESS_ACTIVE_LOCALITY;
221 tpm_tis_spi_write(dev, TPM_ACCESS(loc), &buf, 1);
225 static int tpm_tis_spi_request_locality(struct udevice *dev, int loc)
227 struct tpm_chip *chip = dev_get_priv(dev);
228 unsigned long start, stop;
229 u8 buf = TPM_ACCESS_REQUEST_USE;
232 ret = tpm_tis_spi_check_locality(dev, loc);
236 if (ret != -ENOENT) {
237 log(LOGC_NONE, LOGL_ERR, "%s: Failed to get locality: %d\n",
242 ret = tpm_tis_spi_write(dev, TPM_ACCESS(loc), &buf, 1);
244 log(LOGC_NONE, LOGL_ERR, "%s: Failed to write to TPM: %d\n",
249 start = get_timer(0);
250 stop = chip->timeout_a;
252 ret = tpm_tis_spi_check_locality(dev, loc);
256 if (ret != -ENOENT) {
257 log(LOGC_NONE, LOGL_ERR,
258 "%s: Failed to get locality: %d\n", __func__, ret);
262 mdelay(TPM_TIMEOUT_MS);
263 } while (get_timer(start) < stop);
265 log(LOGC_NONE, LOGL_ERR, "%s: Timeout getting locality: %d\n", __func__,
271 static u8 tpm_tis_spi_status(struct udevice *dev, u8 *status)
273 struct tpm_chip *chip = dev_get_priv(dev);
275 return tpm_tis_spi_read(dev, TPM_STS(chip->locality), status, 1);
278 static int tpm_tis_spi_wait_for_stat(struct udevice *dev, u8 mask,
279 unsigned long timeout, u8 *status)
281 unsigned long start = get_timer(0);
282 unsigned long stop = timeout;
286 mdelay(TPM_TIMEOUT_MS);
287 ret = tpm_tis_spi_status(dev, status);
291 if ((*status & mask) == mask)
293 } while (get_timer(start) < stop);
298 static u8 tpm_tis_spi_valid_status(struct udevice *dev, u8 *status)
300 struct tpm_chip *chip = dev_get_priv(dev);
302 return tpm_tis_spi_wait_for_stat(dev, TPM_STS_VALID,
303 chip->timeout_c, status);
306 static int tpm_tis_spi_get_burstcount(struct udevice *dev)
308 struct tpm_chip *chip = dev_get_priv(dev);
309 unsigned long start, stop;
312 /* wait for burstcount */
313 start = get_timer(0);
314 stop = chip->timeout_d;
316 ret = tpm_tis_spi_read32(dev, TPM_STS(chip->locality),
321 burstcount = (burstcount >> 8) & 0xFFFF;
325 mdelay(TPM_TIMEOUT_MS);
326 } while (get_timer(start) < stop);
331 static int tpm_tis_spi_cancel(struct udevice *dev)
333 struct tpm_chip *chip = dev_get_priv(dev);
334 u8 data = TPM_STS_COMMAND_READY;
336 return tpm_tis_spi_write(dev, TPM_STS(chip->locality), &data, 1);
339 static int tpm_tis_spi_recv_data(struct udevice *dev, u8 *buf, size_t count)
341 struct tpm_chip *chip = dev_get_priv(dev);
342 int size = 0, burstcnt, len, ret;
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);
353 len = min_t(int, burstcnt, count - size);
354 ret = tpm_tis_spi_read(dev, TPM_DATA_FIFO(chip->locality),
365 static int tpm_tis_spi_recv(struct udevice *dev, u8 *buf, size_t count)
367 struct tpm_chip *chip = dev_get_priv(dev);
373 if (count < TPM_HEADER_SIZE) {
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");
384 expected = get_unaligned_be32(buf + 2);
385 if (expected > count) {
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");
400 tpm_tis_spi_cancel(dev);
401 tpm_tis_spi_release_locality(dev, chip->locality, false);
406 static int tpm_tis_spi_send(struct udevice *dev, const u8 *buf, size_t len)
408 struct tpm_chip *chip = dev_get_priv(dev);
417 if (len > TPM_DEV_BUFSIZE)
418 return -E2BIG; /* Command is too long for our tpm, sorry */
420 ret = tpm_tis_spi_request_locality(dev, 0);
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.
428 ret = tpm_tis_spi_status(dev, &status);
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);
436 log(LOGC_NONE, LOGL_ERR,
437 "%s: Could not cancel previous operation\n",
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",
452 for (i = 0; i < len - 1;) {
453 burstcnt = tpm_tis_spi_get_burstcount(dev);
457 size = min_t(int, len - i - 1, burstcnt);
458 ret = tpm_tis_spi_write(dev, TPM_DATA_FIFO(chip->locality),
466 ret = tpm_tis_spi_valid_status(dev, &status);
470 if ((status & TPM_STS_DATA_EXPECT) == 0) {
475 ret = tpm_tis_spi_write(dev, TPM_DATA_FIFO(chip->locality),
480 ret = tpm_tis_spi_valid_status(dev, &status);
484 if ((status & TPM_STS_DATA_EXPECT) != 0) {
490 ret = tpm_tis_spi_write(dev, TPM_STS(chip->locality), &data, 1);
497 tpm_tis_spi_cancel(dev);
498 tpm_tis_spi_release_locality(dev, chip->locality, false);
503 static int tpm_tis_spi_cleanup(struct udevice *dev)
505 struct tpm_chip *chip = dev_get_priv(dev);
507 tpm_tis_spi_cancel(dev);
509 * The TPM needs some time to clean up here,
510 * so we sleep rather than keeping the bus busy
513 tpm_tis_spi_release_locality(dev, chip->locality, false);
518 static int tpm_tis_spi_open(struct udevice *dev)
520 struct tpm_chip *chip = dev_get_priv(dev);
521 struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
531 static int tpm_tis_spi_close(struct udevice *dev)
533 struct tpm_chip *chip = dev_get_priv(dev);
536 tpm_tis_spi_release_locality(dev, chip->locality, true);
543 static int tpm_tis_get_desc(struct udevice *dev, char *buf, int size)
545 struct tpm_chip *chip = dev_get_priv(dev);
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"));
557 static int tpm_tis_wait_init(struct udevice *dev, int loc)
559 struct tpm_chip *chip = dev_get_priv(dev);
560 unsigned long start, stop;
564 start = get_timer(0);
565 stop = chip->timeout_b;
567 mdelay(TPM_TIMEOUT_MS);
569 ret = tpm_tis_spi_read(dev, TPM_ACCESS(loc), &status, 1);
573 if (status & TPM_ACCESS_VALID)
575 } while (get_timer(start) < stop);
580 static int tpm_tis_spi_probe(struct udevice *dev)
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);
587 /* Use the TPM v2 stack */
588 priv->version = TPM_V2;
590 if (IS_ENABLED(CONFIG_DM_GPIO)) {
591 struct gpio_desc reset_gpio;
593 ret = gpio_request_by_name(dev, "gpio-reset", 0,
594 &reset_gpio, GPIOD_IS_OUT);
596 log(LOGC_NONE, LOGL_NOTICE, "%s: missing reset GPIO\n",
599 dm_gpio_set_value(&reset_gpio, 1);
601 dm_gpio_set_value(&reset_gpio, 0);
605 /* Ensure a minimum amount of time elapsed since reset of the TPM */
606 mdelay(drv_data->time_before_first_cmd_ms);
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;
616 ret = tpm_tis_wait_init(dev, chip->locality);
618 log(LOGC_DM, LOGL_ERR, "%s: no device found\n", __func__);
622 ret = tpm_tis_spi_request_locality(dev, chip->locality);
624 log(LOGC_NONE, LOGL_ERR, "%s: could not request locality %d\n",
625 __func__, chip->locality);
629 ret = tpm_tis_spi_read32(dev, TPM_DID_VID(chip->locality),
632 log(LOGC_NONE, LOGL_ERR,
633 "%s: could not retrieve VendorID/DeviceID\n", __func__);
637 ret = tpm_tis_spi_read(dev, TPM_RID(chip->locality), &chip->rid, 1);
639 log(LOGC_NONE, LOGL_ERR, "%s: could not retrieve RevisionID\n",
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);
651 static int tpm_tis_spi_remove(struct udevice *dev)
653 struct tpm_chip *chip = dev_get_priv(dev);
655 tpm_tis_spi_release_locality(dev, chip->locality, true);
660 static 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,
669 static const struct tpm_tis_chip_data tpm_tis_std_chip_data = {
672 .time_before_first_cmd_ms = 30,
675 static const struct udevice_id tpm_tis_spi_ids[] = {
677 .compatible = "tis,tpm2-spi",
678 .data = (ulong)&tpm_tis_std_chip_data,
683 U_BOOT_DRIVER(tpm_tis_spi) = {
684 .name = "tpm_tis_spi",
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),