Commit eb46910b authored by Miquel Raynal's avatar Miquel Raynal Committed by Tom Rini

tpm: add support for TPMv2.x SPI modules

Add the tpm2_tis_spi driver that should support any TPMv2 compliant
(SPI) module.
Signed-off-by: default avatarMiquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Tom Rini's avatarTom Rini <trini@konsulko.com>
Reviewed-by: Simon Glass's avatarSimon Glass <sjg@chromium.org>
parent b9dd4fab
......@@ -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
......@@ -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
// 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)
{