diff options
| -rw-r--r-- | drivers/tpm/Kconfig | 10 | ||||
| -rw-r--r-- | drivers/tpm/Makefile | 2 | ||||
| -rw-r--r-- | drivers/tpm/tpm2_tis_spi.c | 663 |
3 files changed, 675 insertions, 0 deletions
diff --git a/drivers/tpm/Kconfig b/drivers/tpm/Kconfig index bc11f61e91..2de9862371 100644 --- a/drivers/tpm/Kconfig +++ b/drivers/tpm/Kconfig @@ -129,6 +129,16 @@ config TPM_V2 if TPM_V2 && !TPM_V1 +config TPM2_TIS_SPI + bool "Enable support for TPMv2.x SPI chips" + depends on TPM_V2 && DM_SPI + select TPM_DRIVER_SELECTED + help + This driver supports TPMv2.x devices connected on the SPI bus. + The usual TPM operations and the 'tpm' command can be used to talk + to the device using the standard TPM Interface Specification (TIS) + protocol. + endif # TPM_V2 endmenu diff --git a/drivers/tpm/Makefile b/drivers/tpm/Makefile index e5fc86ff95..e4b57615be 100644 --- a/drivers/tpm/Makefile +++ b/drivers/tpm/Makefile @@ -9,3 +9,5 @@ obj-$(CONFIG_TPM_TIS_LPC) += tpm_tis_lpc.o obj-$(CONFIG_TPM_TIS_SANDBOX) += tpm_tis_sandbox.o obj-$(CONFIG_TPM_ST33ZP24_I2C) += tpm_tis_st33zp24_i2c.o obj-$(CONFIG_TPM_ST33ZP24_SPI) += tpm_tis_st33zp24_spi.o + +obj-$(CONFIG_TPM2_TIS_SPI) += tpm2_tis_spi.o diff --git a/drivers/tpm/tpm2_tis_spi.c b/drivers/tpm/tpm2_tis_spi.c new file mode 100644 index 0000000000..518a08b48d --- /dev/null +++ b/drivers/tpm/tpm2_tis_spi.c @@ -0,0 +1,663 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Author: + * Miquel Raynal <miquel.raynal@bootlin.com> + * + * Description: + * SPI-level driver for TCG/TIS TPM (trusted platform module). + * Specifications at www.trustedcomputinggroup.org + * + * This device driver implements the TPM interface as defined in + * the TCG SPI protocol stack version 2.0. + * + * It is based on the U-Boot driver tpm_tis_infineon_i2c.c. + */ + +#include <common.h> +#include <dm.h> +#include <fdtdec.h> +#include <log.h> +#include <spi.h> +#include <tpm-v2.h> +#include <linux/errno.h> +#include <linux/compiler.h> +#include <linux/types.h> +#include <linux/unaligned/be_byteshift.h> + +#include "tpm_tis.h" +#include "tpm_internal.h" + +DECLARE_GLOBAL_DATA_PTR; + +#define TPM_ACCESS(l) (0x0000 | ((l) << 12)) +#define TPM_INT_ENABLE(l) (0x0008 | ((l) << 12)) +#define TPM_STS(l) (0x0018 | ((l) << 12)) +#define TPM_DATA_FIFO(l) (0x0024 | ((l) << 12)) +#define TPM_DID_VID(l) (0x0F00 | ((l) << 12)) +#define TPM_RID(l) (0x0F04 | ((l) << 12)) + +#define MAX_SPI_FRAMESIZE 64 + +/* Number of wait states to wait for */ +#define TPM_WAIT_STATES 100 + +/** + * struct tpm_tis_chip_data - Non-discoverable TPM information + * + * @pcr_count: Number of PCR per bank + * @pcr_select_min: Size in octets of the pcrSelect array + */ +struct tpm_tis_chip_data { + unsigned int pcr_count; + unsigned int pcr_select_min; + unsigned int time_before_first_cmd_ms; +}; + +/** + * tpm_tis_spi_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_spi_xfer(struct udevice *dev, u32 addr, const u8 *out, + u8 *in, u16 len) +{ + struct spi_slave *slave = dev_get_parent_priv(dev); + int transfer_len, ret; + u8 tx_buf[MAX_SPI_FRAMESIZE]; + u8 rx_buf[MAX_SPI_FRAMESIZE]; + + if (in && out) { + log(LOGC_NONE, LOGL_ERR, "%s: can't do full duplex\n", + __func__); + return -EINVAL; + } + + ret = spi_claim_bus(slave); + if (ret < 0) { + log(LOGC_NONE, LOGL_ERR, "%s: could not claim bus\n", __func__); + return ret; + } + + while (len) { + /* Request */ + transfer_len = min_t(u16, len, MAX_SPI_FRAMESIZE); + tx_buf[0] = (in ? BIT(7) : 0) | (transfer_len - 1); + tx_buf[1] = 0xD4; + tx_buf[2] = addr >> 8; + tx_buf[3] = addr; + + ret = spi_xfer(slave, 4 * 8, tx_buf, rx_buf, SPI_XFER_BEGIN); + if (ret < 0) { + log(LOGC_NONE, LOGL_ERR, + "%s: spi request transfer failed (err: %d)\n", + __func__, ret); + goto release_bus; + } + + /* Wait state */ + if (!(rx_buf[3] & 0x1)) { + int i; + + for (i = 0; i < TPM_WAIT_STATES; i++) { + ret = spi_xfer(slave, 1 * 8, NULL, rx_buf, 0); + if (ret) { + log(LOGC_NONE, LOGL_ERR, + "%s: wait state failed: %d\n", + __func__, ret); + goto release_bus; + } + + if (rx_buf[0] & 0x1) + break; + } + + if (i == TPM_WAIT_STATES) { + log(LOGC_NONE, LOGL_ERR, + "%s: timeout on wait state\n", __func__); + ret = -ETIMEDOUT; + goto release_bus; + } + } + + /* Read/Write */ + if (out) { + memcpy(tx_buf, out, transfer_len); + out += transfer_len; + } + + ret = spi_xfer(slave, transfer_len * 8, + out ? tx_buf : NULL, + in ? rx_buf : NULL, + SPI_XFER_END); + if (ret) { + log(LOGC_NONE, LOGL_ERR, + "%s: spi read transfer failed (err: %d)\n", + __func__, ret); + goto release_bus; + } + + if (in) { + memcpy(in, rx_buf, transfer_len); + in += transfer_len; + } + + len -= transfer_len; + } + +release_bus: + /* If an error occurred, release the chip by deasserting the CS */ + if (ret < 0) + spi_xfer(slave, 0, NULL, NULL, SPI_XFER_END); + + spi_release_bus(slave); + + return ret; +} + +static int tpm_tis_spi_read(struct udevice *dev, u16 addr, u8 *in, u16 len) +{ + return tpm_tis_spi_xfer(dev, addr, NULL, in, len); +} + +static int tpm_tis_spi_read32(struct udevice *dev, u32 addr, u32 *result) +{ + __le32 result_le; + int ret; + + ret = tpm_tis_spi_read(dev, addr, (u8 *)&result_le, sizeof(u32)); + if (!ret) + *result = le32_to_cpu(result_le); + + return ret; +} + +static int tpm_tis_spi_write(struct udevice *dev, u16 addr, const u8 *out, + u16 len) +{ + return tpm_tis_spi_xfer(dev, addr, out, NULL, len); +} + +static int tpm_tis_spi_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 ret; + + ret = tpm_tis_spi_read(dev, TPM_ACCESS(loc), &buf, 1); + if (ret) + return ret; + + if ((buf & mask) == mask) { + chip->locality = loc; + return 0; + } + + return -ENOENT; +} + +static void tpm_tis_spi_release_locality(struct udevice *dev, int loc, + bool force) +{ + const u8 mask = TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID; + u8 buf; + + if (tpm_tis_spi_read(dev, TPM_ACCESS(loc), &buf, 1) < 0) + return; + + if (force || (buf & mask) == mask) { + buf = TPM_ACCESS_ACTIVE_LOCALITY; + tpm_tis_spi_write(dev, TPM_ACCESS(loc), &buf, 1); + } +} + +static int tpm_tis_spi_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 ret; + + ret = tpm_tis_spi_check_locality(dev, loc); + if (!ret) + return 0; + + if (ret != -ENOENT) { + log(LOGC_NONE, LOGL_ERR, "%s: Failed to get locality: %d\n", + __func__, ret); + return ret; + } + + ret = tpm_tis_spi_write(dev, TPM_ACCESS(loc), &buf, 1); + if (ret) { + log(LOGC_NONE, LOGL_ERR, "%s: Failed to write to TPM: %d\n", + __func__, ret); + return ret; + } + + start = get_timer(0); + stop = chip->timeout_a; + do { + ret = tpm_tis_spi_check_locality(dev, loc); + if (!ret) + return 0; + + if (ret != -ENOENT) { + log(LOGC_NONE, LOGL_ERR, + "%s: Failed to get locality: %d\n", __func__, ret); + return ret; + } + + mdelay(TPM_TIMEOUT_MS); + } while (get_timer(start) < stop); + + log(LOGC_NONE, LOGL_ERR, "%s: Timeout getting locality: %d\n", __func__, + ret); + + return ret; +} + +static u8 tpm_tis_spi_status(struct udevice *dev, u8 *status) +{ + struct tpm_chip *chip = dev_get_priv(dev); + + return tpm_tis_spi_read(dev, TPM_STS(chip->locality), status, 1); +} + +static int tpm_tis_spi_wait_for_stat(struct udevice *dev, u8 mask, + unsigned long timeout, u8 *status) +{ + unsigned long start = get_timer(0); + unsigned long stop = timeout; + int ret; + + do { + mdelay(TPM_TIMEOUT_MS); + ret = tpm_tis_spi_status(dev, status); + if (ret) + return ret; + + if ((*status & mask) == mask) + return 0; + } while (get_timer(start) < stop); + + return -ETIMEDOUT; +} + +static int tpm_tis_spi_get_burstcount(struct udevice *dev) +{ + struct tpm_chip *chip = dev_get_priv(dev); + unsigned long start, stop; + u32 burstcount, ret; + + /* wait for burstcount */ + start = get_timer(0); + stop = chip->timeout_d; + do { + ret = tpm_tis_spi_read32(dev, TPM_STS(chip->locality), + &burstcount); + if (ret) + return -EBUSY; + + burstcount = (burstcount >> 8) & 0xFFFF; + if (burstcount) + return burstcount; + + mdelay(TPM_TIMEOUT_MS); + } while (get_timer(start) < stop); + + return -EBUSY; +} + +static int tpm_tis_spi_cancel(struct udevice *dev) +{ + struct tpm_chip *chip = dev_get_priv(dev); + u8 data = TPM_STS_COMMAND_READY; + + return tpm_tis_spi_write(dev, TPM_STS(chip->locality), &data, 1); +} + +static int tpm_tis_spi_recv_data(struct udevice *dev, u8 *buf, size_t count) +{ + struct tpm_chip *chip = dev_get_priv(dev); + int size = 0, burstcnt, len, ret; + u8 status; + + while (size < count && + tpm_tis_spi_wait_for_stat(dev, + TPM_STS_DATA_AVAIL | TPM_STS_VALID, + chip->timeout_c, &status) == 0) { + burstcnt = tpm_tis_spi_get_burstcount(dev); + if (burstcnt < 0) + return burstcnt; + + len = min_t(int, burstcnt, count - size); + ret = tpm_tis_spi_read(dev, TPM_DATA_FIFO(chip->locality), + buf + size, len); + if (ret < 0) + return ret; + + size += len; + } + + return size; +} + +static int tpm_tis_spi_recv(struct udevice *dev, u8 *buf, size_t count) +{ + struct tpm_chip *chip = dev_get_priv(dev); + int size, expected; + + if (!chip) + return -ENODEV; + + if (count < TPM_HEADER_SIZE) { + size = -EIO; + goto out; + } + + size = tpm_tis_spi_recv_data(dev, buf, TPM_HEADER_SIZE); + if (size < TPM_HEADER_SIZE) { + log(LOGC_NONE, LOGL_ERR, "TPM error, unable to read header\n"); + goto out; + } + + expected = get_unaligned_be32(buf + 2); + if (expected > count) { + size = -EIO; + goto out; + } + + size += tpm_tis_spi_recv_data(dev, &buf[TPM_HEADER_SIZE], + expected - TPM_HEADER_SIZE); + if (size < expected) { + log(LOGC_NONE, LOGL_ERR, + "TPM error, unable to read remaining bytes of result\n"); + size = -EIO; + goto out; + } + +out: + tpm_tis_spi_cancel(dev); + tpm_tis_spi_release_locality(dev, chip->locality, false); + + return size; +} + +static int tpm_tis_spi_send(struct udevice *dev, const u8 *buf, size_t len) +{ + struct tpm_chip *chip = dev_get_priv(dev); + u32 i, size; + u8 status; + int burstcnt, ret; + u8 data; + + if (!chip) + return -ENODEV; + + if (len > TPM_DEV_BUFSIZE) + return -E2BIG; /* Command is too long for our tpm, sorry */ + + ret = tpm_tis_spi_request_locality(dev, 0); + if (ret < 0) + return -EBUSY; + + /* + * Check if the TPM is ready. If not, if not, cancel the pending command + * and poll on the status to be finally ready. + */ + ret = tpm_tis_spi_status(dev, &status); + if (ret) + return ret; + + if (!(status & TPM_STS_COMMAND_READY)) { + /* Force the transition, usually this will be done at startup */ + ret = tpm_tis_spi_cancel(dev); + if (ret) { + log(LOGC_NONE, LOGL_ERR, + "%s: Could not cancel previous operation\n", + __func__); + goto out_err; + } + + ret = tpm_tis_spi_wait_for_stat(dev, TPM_STS_COMMAND_READY, + chip->timeout_b, &status); + if (ret < 0 || !(status & TPM_STS_COMMAND_READY)) { + log(LOGC_NONE, LOGL_ERR, + "status %d after wait for stat returned %d\n", + status, ret); + goto out_err; + } + } + + for (i = 0; i < len - 1;) { + burstcnt = tpm_tis_spi_get_burstcount(dev); + if (burstcnt < 0) + return burstcnt; + + size = min_t(int, len - i - 1, burstcnt); + ret = tpm_tis_spi_write(dev, TPM_DATA_FIFO(chip->locality), + buf + i, size); + if (ret < 0) + goto out_err; + + i += size; + } + + ret = tpm_tis_spi_status(dev, &status); + if (ret) + goto out_err; + + if ((status & TPM_STS_DATA_EXPECT) == 0) { + ret = -EIO; + goto out_err; + } + + ret = tpm_tis_spi_write(dev, TPM_DATA_FIFO(chip->locality), + buf + len - 1, 1); + if (ret) + goto out_err; + + ret = tpm_tis_spi_status(dev, &status); + if (ret) + goto out_err; + + if ((status & TPM_STS_DATA_EXPECT) != 0) { + ret = -EIO; + goto out_err; + } + + data = TPM_STS_GO; + ret = tpm_tis_spi_write(dev, TPM_STS(chip->locality), &data, 1); + if (ret) + goto out_err; + + return len; + +out_err: + tpm_tis_spi_cancel(dev); + tpm_tis_spi_release_locality(dev, chip->locality, false); + + return ret; +} + +static int tpm_tis_spi_cleanup(struct udevice *dev) +{ + struct tpm_chip *chip = dev_get_priv(dev); + + tpm_tis_spi_cancel(dev); + /* + * The TPM needs some time to clean up here, + * so we sleep rather than keeping the bus busy + */ + mdelay(2); + tpm_tis_spi_release_locality(dev, chip->locality, false); + + return 0; +} + +static int tpm_tis_spi_open(struct udevice *dev) +{ + struct tpm_chip *chip = dev_get_priv(dev); + + if (chip->is_open) + return -EBUSY; + + chip->is_open = 1; + + return 0; +} + +static int tpm_tis_spi_close(struct udevice *dev) +{ + struct tpm_chip *chip = dev_get_priv(dev); + + if (chip->is_open) { + tpm_tis_spi_release_locality(dev, chip->locality, true); + chip->is_open = 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 < 80) + return -ENOSPC; + + return snprintf(buf, size, + "%s v2.0: VendorID 0x%04x, DeviceID 0x%04x, RevisionID 0x%02x [%s]", + dev->name, chip->vend_dev & 0xFFFF, + chip->vend_dev >> 16, chip->rid, + (chip->is_open ? "open" : "closed")); +} + +static int tpm_tis_wait_init(struct udevice *dev, int loc) +{ + struct tpm_chip *chip = dev_get_priv(dev); + unsigned long start, stop; + u8 status; + int ret; + + start = get_timer(0); + stop = chip->timeout_b; + do { + mdelay(TPM_TIMEOUT_MS); + + ret = tpm_tis_spi_read(dev, TPM_ACCESS(loc), &status, 1); + if (ret) + break; + + if (status & TPM_ACCESS_VALID) + return 0; + } while (get_timer(start) < stop); + + return -EIO; +} + +static int tpm_tis_spi_probe(struct udevice *dev) +{ + struct tpm_tis_chip_data *drv_data = (void *)dev_get_driver_data(dev); + struct tpm_chip_priv *priv = dev_get_uclass_priv(dev); + struct tpm_chip *chip = dev_get_priv(dev); + int ret; + + /* Ensure a minimum amount of time elapsed since reset of the TPM */ + mdelay(drv_data->time_before_first_cmd_ms); + + chip->locality = 0; + 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; + priv->pcr_count = drv_data->pcr_count; + priv->pcr_select_min = drv_data->pcr_select_min; + + ret = tpm_tis_wait_init(dev, chip->locality); + if (ret) { + log(LOGC_DM, LOGL_ERR, "%s: no device found\n", __func__); + return ret; + } + + ret = tpm_tis_spi_request_locality(dev, chip->locality); + if (ret) { + log(LOGC_NONE, LOGL_ERR, "%s: could not request locality %d\n", + __func__, chip->locality); + return ret; + } + + ret = tpm_tis_spi_read32(dev, TPM_DID_VID(chip->locality), + &chip->vend_dev); + if (ret) { + log(LOGC_NONE, LOGL_ERR, + "%s: could not retrieve VendorID/DeviceID\n", __func__); + return ret; + } + + ret = tpm_tis_spi_read(dev, TPM_RID(chip->locality), &chip->rid, 1); + if (ret) { + log(LOGC_NONE, LOGL_ERR, "%s: could not retrieve RevisionID\n", + __func__); + return ret; + } + + log(LOGC_NONE, LOGL_ERR, + "SPI TPMv2.0 found (vid:%04x, did:%04x, rid:%02x)\n", + chip->vend_dev & 0xFFFF, chip->vend_dev >> 16, chip->rid); + + return 0; +} + +static int tpm_tis_spi_remove(struct udevice *dev) +{ + struct tpm_chip *chip = dev_get_priv(dev); + + tpm_tis_spi_release_locality(dev, chip->locality, true); + + return 0; +} + +static const struct tpm_ops tpm_tis_spi_ops = { + .open = tpm_tis_spi_open, + .close = tpm_tis_spi_close, + .get_desc = tpm_tis_get_desc, + .send = tpm_tis_spi_send, + .recv = tpm_tis_spi_recv, + .cleanup = tpm_tis_spi_cleanup, +}; + +static const struct tpm_tis_chip_data tpm_tis_std_chip_data = { + .pcr_count = 24, + .pcr_select_min = 3, + .time_before_first_cmd_ms = 30, +}; + +static const struct udevice_id tpm_tis_spi_ids[] = { + { + .compatible = "tis,tpm2-spi", + .data = (ulong)&tpm_tis_std_chip_data, + }, + { } +}; + +U_BOOT_DRIVER(tpm_tis_spi) = { + .name = "tpm_tis_spi", + .id = UCLASS_TPM, + .of_match = tpm_tis_spi_ids, + .ops = &tpm_tis_spi_ops, + .probe = tpm_tis_spi_probe, + .remove = tpm_tis_spi_remove, + .priv_auto_alloc_size = sizeof(struct tpm_chip), +}; |