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-rw-r--r--drivers/tpm/tpm_tis_infineon.c623
1 files changed, 623 insertions, 0 deletions
diff --git a/drivers/tpm/tpm_tis_infineon.c b/drivers/tpm/tpm_tis_infineon.c
new file mode 100644
index 00000000000..88eb7869bcd
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+++ b/drivers/tpm/tpm_tis_infineon.c
@@ -0,0 +1,623 @@
+/*
+ * Copyright (C) 2011 Infineon Technologies
+ *
+ * Authors:
+ * Peter Huewe <huewe.external@infineon.com>
+ *
+ * Description:
+ * Device driver for TCG/TCPA TPM (trusted platform module).
+ * Specifications at www.trustedcomputinggroup.org
+ *
+ * This device driver implements the TPM interface as defined in
+ * the TCG TPM Interface Spec version 1.2, revision 1.0 and the
+ * Infineon I2C Protocol Stack Specification v0.20.
+ *
+ * It is based on the Linux kernel driver tpm.c from Leendert van
+ * Dorn, Dave Safford, Reiner Sailer, and Kyleen Hall.
+ *
+ * Version: 2.1.1
+ *
+ * SPDX-License-Identifier: GPL-2.0
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <fdtdec.h>
+#include <i2c.h>
+#include <tis.h>
+#include <tpm.h>
+#include <asm-generic/errno.h>
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <linux/unaligned/be_byteshift.h>
+
+#include "tpm_tis_infineon.h"
+#include "tpm_internal.h"
+
+DECLARE_GLOBAL_DATA_PTR;
+
+static const char * const chip_name[] = {
+ [SLB9635] = "slb9635tt",
+ [SLB9645] = "slb9645tt",
+ [UNKNOWN] = "unknown/fallback to slb9635",
+};
+
+/*
+ * tpm_tis_i2c_read() - read from TPM register
+ * @addr: register address to read from
+ * @buffer: provided by caller
+ * @len: number of bytes to read
+ *
+ * Read len bytes from TPM register and put them into
+ * buffer (little-endian format, i.e. first byte is put into buffer[0]).
+ *
+ * NOTE: TPM is big-endian for multi-byte values. Multi-byte
+ * values have to be swapped.
+ *
+ * Return -EIO on error, 0 on success.
+ */
+static int tpm_tis_i2c_read(struct udevice *dev, u8 addr, u8 *buffer,
+ size_t len)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ int rc;
+ int count;
+ uint32_t addrbuf = addr;
+
+ if ((chip->chip_type == SLB9635) || (chip->chip_type == UNKNOWN)) {
+ /* slb9635 protocol should work in both cases */
+ for (count = 0; count < MAX_COUNT; count++) {
+ rc = dm_i2c_write(dev, 0, (uchar *)&addrbuf, 1);
+ if (rc == 0)
+ break; /* Success, break to skip sleep */
+ udelay(SLEEP_DURATION_US);
+ }
+ if (rc)
+ return rc;
+
+ /* After the TPM has successfully received the register address
+ * it needs some time, thus we're sleeping here again, before
+ * retrieving the data
+ */
+ for (count = 0; count < MAX_COUNT; count++) {
+ udelay(SLEEP_DURATION_US);
+ rc = dm_i2c_read(dev, 0, buffer, len);
+ if (rc == 0)
+ break; /* success, break to skip sleep */
+ }
+ } else {
+ /*
+ * Use a combined read for newer chips.
+ * Unfortunately the smbus functions are not suitable due to
+ * the 32 byte limit of the smbus.
+ * Retries should usually not be needed, but are kept just to
+ * be safe on the safe side.
+ */
+ for (count = 0; count < MAX_COUNT; count++) {
+ rc = dm_i2c_read(dev, addr, buffer, len);
+ if (rc == 0)
+ break; /* break here to skip sleep */
+ udelay(SLEEP_DURATION_US);
+ }
+ }
+
+ /* Take care of 'guard time' */
+ udelay(SLEEP_DURATION_US);
+ if (rc)
+ return rc;
+
+ return 0;
+}
+
+static int tpm_tis_i2c_write_generic(struct udevice *dev, u8 addr,
+ const u8 *buffer, size_t len,
+ unsigned int sleep_time_us, u8 max_count)
+{
+ struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
+ struct tpm_chip *chip = dev_get_priv(dev);
+ int rc = 0;
+ int count;
+
+ if (chip->chip_type == SLB9635) {
+ /* Prepare send buffer to include the address */
+ priv->buf[0] = addr;
+ memcpy(&(priv->buf[1]), buffer, len);
+ buffer = priv->buf;
+ len++;
+ addr = 0;
+ }
+
+ for (count = 0; count < max_count; count++) {
+ rc = dm_i2c_write(dev, addr, buffer, len);
+ if (rc == 0)
+ break; /* Success, break to skip sleep */
+ udelay(sleep_time_us);
+ }
+
+ /* take care of 'guard time' */
+ udelay(sleep_time_us);
+ if (rc)
+ return rc;
+
+ return 0;
+}
+
+/*
+ * tpm_tis_i2c_write() - write to TPM register
+ * @addr: register address to write to
+ * @buffer: containing data to be written
+ * @len: number of bytes to write
+ *
+ * Write len bytes from provided buffer to TPM register (little
+ * endian format, i.e. buffer[0] is written as first byte).
+ *
+ * NOTE: TPM is big-endian for multi-byte values. Multi-byte
+ * values have to be swapped.
+ *
+ * NOTE: use this function instead of the tpm_tis_i2c_write_generic function.
+ *
+ * Return -EIO on error, 0 on success
+ */
+static int tpm_tis_i2c_write(struct udevice *dev, u8 addr, const u8 *buffer,
+ size_t len)
+{
+ return tpm_tis_i2c_write_generic(dev, addr, buffer, len,
+ SLEEP_DURATION_US, MAX_COUNT);
+}
+
+/*
+ * This function is needed especially for the cleanup situation after
+ * sending TPM_READY
+ */
+static int tpm_tis_i2c_write_long(struct udevice *dev, u8 addr, u8 *buffer,
+ size_t len)
+{
+ return tpm_tis_i2c_write_generic(dev, addr, buffer, len,
+ SLEEP_DURATION_LONG_US,
+ MAX_COUNT_LONG);
+}
+
+static int tpm_tis_i2c_check_locality(struct udevice *dev, int loc)
+{
+ const u8 mask = TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID;
+ struct tpm_chip *chip = dev_get_priv(dev);
+ u8 buf;
+ int rc;
+
+ rc = tpm_tis_i2c_read(dev, TPM_ACCESS(loc), &buf, 1);
+ if (rc < 0)
+ return rc;
+
+ if ((buf & mask) == mask) {
+ chip->locality = loc;
+ return loc;
+ }
+
+ return -ENOENT;
+}
+
+static void tpm_tis_i2c_release_locality(struct udevice *dev, int loc,
+ int force)
+{
+ const u8 mask = TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID;
+ u8 buf;
+
+ if (tpm_tis_i2c_read(dev, TPM_ACCESS(loc), &buf, 1) < 0)
+ return;
+
+ if (force || (buf & mask) == mask) {
+ buf = TPM_ACCESS_ACTIVE_LOCALITY;
+ tpm_tis_i2c_write(dev, TPM_ACCESS(loc), &buf, 1);
+ }
+}
+
+static int tpm_tis_i2c_request_locality(struct udevice *dev, int loc)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ unsigned long start, stop;
+ u8 buf = TPM_ACCESS_REQUEST_USE;
+ int rc;
+
+ rc = tpm_tis_i2c_check_locality(dev, loc);
+ if (rc >= 0) {
+ debug("%s: Already have locality\n", __func__);
+ return loc; /* We already have the locality */
+ } else if (rc != -ENOENT) {
+ debug("%s: Failed to get locality: %d\n", __func__, rc);
+ return rc;
+ }
+
+ rc = tpm_tis_i2c_write(dev, TPM_ACCESS(loc), &buf, 1);
+ if (rc) {
+ debug("%s: Failed to write to TPM: %d\n", __func__, rc);
+ return rc;
+ }
+
+ /* Wait for burstcount */
+ start = get_timer(0);
+ stop = chip->timeout_a;
+ do {
+ rc = tpm_tis_i2c_check_locality(dev, loc);
+ if (rc >= 0) {
+ debug("%s: Have locality\n", __func__);
+ return loc;
+ } else if (rc != -ENOENT) {
+ debug("%s: Failed to get locality: %d\n", __func__, rc);
+ return rc;
+ }
+ mdelay(TPM_TIMEOUT_MS);
+ } while (get_timer(start) < stop);
+ debug("%s: Timeout getting locality: %d\n", __func__, rc);
+
+ return rc;
+}
+
+static u8 tpm_tis_i2c_status(struct udevice *dev)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ /* NOTE: Since i2c read may fail, return 0 in this case --> time-out */
+ u8 buf;
+
+ if (tpm_tis_i2c_read(dev, TPM_STS(chip->locality), &buf, 1) < 0)
+ return 0;
+ else
+ return buf;
+}
+
+static int tpm_tis_i2c_ready(struct udevice *dev)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ int rc;
+
+ /* This causes the current command to be aborted */
+ u8 buf = TPM_STS_COMMAND_READY;
+
+ debug("%s\n", __func__);
+ rc = tpm_tis_i2c_write_long(dev, TPM_STS(chip->locality), &buf, 1);
+ if (rc)
+ debug("%s: rc=%d\n", __func__, rc);
+
+ return rc;
+}
+
+static ssize_t tpm_tis_i2c_get_burstcount(struct udevice *dev)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ unsigned long start, stop;
+ ssize_t burstcnt;
+ u8 addr, buf[3];
+
+ /* Wait for burstcount */
+ /* XXX: Which timeout value? Spec has 2 answers (c & d) */
+ start = get_timer(0);
+ stop = chip->timeout_d;
+ do {
+ /* Note: STS is little endian */
+ addr = TPM_STS(chip->locality) + 1;
+ if (tpm_tis_i2c_read(dev, addr, buf, 3) < 0)
+ burstcnt = 0;
+ else
+ burstcnt = (buf[2] << 16) + (buf[1] << 8) + buf[0];
+
+ if (burstcnt)
+ return burstcnt;
+ mdelay(TPM_TIMEOUT_MS);
+ } while (get_timer(start) < stop);
+
+ return -EBUSY;
+}
+
+static int tpm_tis_i2c_wait_for_stat(struct udevice *dev, u8 mask,
+ unsigned long timeout, int *status)
+{
+ unsigned long start, stop;
+
+ /* Check current status */
+ *status = tpm_tis_i2c_status(dev);
+ if ((*status & mask) == mask)
+ return 0;
+
+ start = get_timer(0);
+ stop = timeout;
+ do {
+ mdelay(TPM_TIMEOUT_MS);
+ *status = tpm_tis_i2c_status(dev);
+ if ((*status & mask) == mask)
+ return 0;
+ } while (get_timer(start) < stop);
+
+ return -ETIMEDOUT;
+}
+
+static int tpm_tis_i2c_recv_data(struct udevice *dev, u8 *buf, size_t count)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ size_t size = 0;
+ ssize_t burstcnt;
+ int rc;
+
+ while (size < count) {
+ burstcnt = tpm_tis_i2c_get_burstcount(dev);
+
+ /* burstcount < 0 -> tpm is busy */
+ if (burstcnt < 0)
+ return burstcnt;
+
+ /* Limit received data to max left */
+ if (burstcnt > (count - size))
+ burstcnt = count - size;
+
+ rc = tpm_tis_i2c_read(dev, TPM_DATA_FIFO(chip->locality),
+ &(buf[size]), burstcnt);
+ if (rc == 0)
+ size += burstcnt;
+ }
+
+ return size;
+}
+
+static int tpm_tis_i2c_recv(struct udevice *dev, u8 *buf, size_t count)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ int size = 0;
+ int expected, status;
+ int rc;
+
+ status = tpm_tis_i2c_status(dev);
+ if (status == TPM_STS_COMMAND_READY)
+ return -EINTR;
+ if ((status & (TPM_STS_DATA_AVAIL | TPM_STS_VALID)) !=
+ (TPM_STS_DATA_AVAIL | TPM_STS_VALID))
+ return -EAGAIN;
+
+ debug("...got it;\n");
+
+ /* Read first 10 bytes, including tag, paramsize, and result */
+ size = tpm_tis_i2c_recv_data(dev, buf, TPM_HEADER_SIZE);
+ if (size < TPM_HEADER_SIZE) {
+ debug("Unable to read header\n");
+ return size < 0 ? size : -EIO;
+ }
+
+ expected = get_unaligned_be32(buf + TPM_RSP_SIZE_BYTE);
+ if ((size_t)expected > count) {
+ debug("Error size=%x, expected=%x, count=%x\n", size, expected,
+ count);
+ return -ENOSPC;
+ }
+
+ size += tpm_tis_i2c_recv_data(dev, &buf[TPM_HEADER_SIZE],
+ expected - TPM_HEADER_SIZE);
+ if (size < expected) {
+ debug("Unable to read remainder of result\n");
+ return -ETIMEDOUT;
+ }
+
+ rc = tpm_tis_i2c_wait_for_stat(dev, TPM_STS_VALID, chip->timeout_c,
+ &status);
+ if (rc)
+ return rc;
+ if (status & TPM_STS_DATA_AVAIL) { /* Retry? */
+ debug("Error left over data\n");
+ return -EIO;
+ }
+
+ return size;
+}
+
+static int tpm_tis_i2c_send(struct udevice *dev, const u8 *buf, size_t len)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ int rc, status;
+ size_t burstcnt;
+ size_t count = 0;
+ int retry = 0;
+ u8 sts = TPM_STS_GO;
+
+ debug("%s: len=%d\n", __func__, len);
+ if (len > TPM_DEV_BUFSIZE)
+ return -E2BIG; /* Command is too long for our tpm, sorry */
+
+ if (tpm_tis_i2c_request_locality(dev, 0) < 0)
+ return -EBUSY;
+
+ status = tpm_tis_i2c_status(dev);
+ if ((status & TPM_STS_COMMAND_READY) == 0) {
+ rc = tpm_tis_i2c_ready(dev);
+ if (rc)
+ return rc;
+ rc = tpm_tis_i2c_wait_for_stat(dev, TPM_STS_COMMAND_READY,
+ chip->timeout_b, &status);
+ if (rc)
+ return rc;
+ }
+
+ burstcnt = tpm_tis_i2c_get_burstcount(dev);
+
+ /* burstcount < 0 -> tpm is busy */
+ if (burstcnt < 0)
+ return burstcnt;
+
+ while (count < len) {
+ udelay(300);
+ if (burstcnt > len - count)
+ burstcnt = len - count;
+
+#ifdef CONFIG_TPM_TIS_I2C_BURST_LIMITATION
+ if (retry && burstcnt > CONFIG_TPM_TIS_I2C_BURST_LIMITATION_LEN)
+ burstcnt = CONFIG_TPM_TIS_I2C_BURST_LIMITATION_LEN;
+#endif /* CONFIG_TPM_TIS_I2C_BURST_LIMITATION */
+
+ rc = tpm_tis_i2c_write(dev, TPM_DATA_FIFO(chip->locality),
+ &(buf[count]), burstcnt);
+ if (rc == 0)
+ count += burstcnt;
+ else {
+ debug("%s: error\n", __func__);
+ if (retry++ > 10)
+ return -EIO;
+ rc = tpm_tis_i2c_wait_for_stat(dev, TPM_STS_VALID,
+ chip->timeout_c,
+ &status);
+ if (rc)
+ return rc;
+
+ if ((status & TPM_STS_DATA_EXPECT) == 0)
+ return -EIO;
+ }
+ }
+
+ /* Go and do it */
+ rc = tpm_tis_i2c_write(dev, TPM_STS(chip->locality), &sts, 1);
+ if (rc < 0)
+ return rc;
+ debug("%s: done, rc=%d\n", __func__, rc);
+
+ return len;
+}
+
+static int tpm_tis_i2c_cleanup(struct udevice *dev)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+
+ tpm_tis_i2c_ready(dev);
+ /*
+ * The TPM needs some time to clean up here,
+ * so we sleep rather than keeping the bus busy
+ */
+ mdelay(2);
+ tpm_tis_i2c_release_locality(dev, chip->locality, 0);
+
+ return 0;
+}
+
+static int tpm_tis_i2c_init(struct udevice *dev)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ u32 vendor;
+ u32 expected_did_vid;
+ int rc;
+
+ chip->is_open = 1;
+
+ /* Default timeouts - these could move to the device tree */
+ chip->timeout_a = TIS_SHORT_TIMEOUT_MS;
+ chip->timeout_b = TIS_LONG_TIMEOUT_MS;
+ chip->timeout_c = TIS_SHORT_TIMEOUT_MS;
+ chip->timeout_d = TIS_SHORT_TIMEOUT_MS;
+
+ rc = tpm_tis_i2c_request_locality(dev, 0);
+ if (rc < 0)
+ return rc;
+
+ /* Read four bytes from DID_VID register */
+ if (tpm_tis_i2c_read(dev, TPM_DID_VID(0), (uchar *)&vendor, 4) < 0) {
+ tpm_tis_i2c_release_locality(dev, 0, 1);
+ return -EIO;
+ }
+
+ if (chip->chip_type == SLB9635) {
+ vendor = be32_to_cpu(vendor);
+ expected_did_vid = TPM_TIS_I2C_DID_VID_9635;
+ } else {
+ /* device id and byte order has changed for newer i2c tpms */
+ expected_did_vid = TPM_TIS_I2C_DID_VID_9645;
+ }
+
+ if (chip->chip_type != UNKNOWN && vendor != expected_did_vid) {
+ error("Vendor id did not match! ID was %08x\n", vendor);
+ return -ENODEV;
+ }
+
+ chip->vend_dev = vendor;
+ debug("1.2 TPM (chip type %s device-id 0x%X)\n",
+ chip_name[chip->chip_type], vendor >> 16);
+
+ /*
+ * A timeout query to TPM can be placed here.
+ * Standard timeout values are used so far
+ */
+
+ return 0;
+}
+
+static int tpm_tis_i2c_open(struct udevice *dev)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+ int rc;
+
+ debug("%s: start\n", __func__);
+ if (chip->is_open)
+ return -EBUSY;
+ rc = tpm_tis_i2c_init(dev);
+ if (rc < 0)
+ chip->is_open = 0;
+
+ return rc;
+}
+
+static int tpm_tis_i2c_close(struct udevice *dev)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+
+ if (chip->is_open) {
+ tpm_tis_i2c_release_locality(dev, chip->locality, 1);
+ chip->is_open = 0;
+ chip->vend_dev = 0;
+ }
+
+ return 0;
+}
+
+static int tpm_tis_get_desc(struct udevice *dev, char *buf, int size)
+{
+ struct tpm_chip *chip = dev_get_priv(dev);
+
+ if (size < 50)
+ return -ENOSPC;
+
+ return snprintf(buf, size, "1.2 TPM (%s, chip type %s device-id 0x%x)",
+ chip->is_open ? "open" : "closed",
+ chip_name[chip->chip_type],
+ chip->vend_dev >> 16);
+}
+
+static int tpm_tis_i2c_probe(struct udevice *dev)
+{
+ struct tpm_chip_priv *uc_priv = dev_get_uclass_priv(dev);
+ struct tpm_chip *chip = dev_get_priv(dev);
+
+ chip->chip_type = dev_get_driver_data(dev);
+
+ /* TODO: These need to be checked and tuned */
+ uc_priv->duration_ms[TPM_SHORT] = TIS_SHORT_TIMEOUT_MS;
+ uc_priv->duration_ms[TPM_MEDIUM] = TIS_LONG_TIMEOUT_MS;
+ uc_priv->duration_ms[TPM_LONG] = TIS_LONG_TIMEOUT_MS;
+ uc_priv->retry_time_ms = TPM_TIMEOUT_MS;
+
+ return 0;
+}
+
+static const struct tpm_ops tpm_tis_i2c_ops = {
+ .open = tpm_tis_i2c_open,
+ .close = tpm_tis_i2c_close,
+ .get_desc = tpm_tis_get_desc,
+ .send = tpm_tis_i2c_send,
+ .recv = tpm_tis_i2c_recv,
+ .cleanup = tpm_tis_i2c_cleanup,
+};
+
+static const struct udevice_id tpm_tis_i2c_ids[] = {
+ { .compatible = "infineon,slb9635tt", .data = SLB9635 },
+ { .compatible = "infineon,slb9645tt", .data = SLB9645 },
+ { }
+};
+
+U_BOOT_DRIVER(tpm_tis_i2c) = {
+ .name = "tpm_tis_infineon",
+ .id = UCLASS_TPM,
+ .of_match = tpm_tis_i2c_ids,
+ .ops = &tpm_tis_i2c_ops,
+ .probe = tpm_tis_i2c_probe,
+ .priv_auto_alloc_size = sizeof(struct tpm_chip),
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-16 03:40:59 +0000