u-boot/drivers/tpm/tpm_tis_st33zp24_i2c.c
Simon Glass 41575d8e4c dm: treewide: Rename auto_alloc_size members to be shorter
This construct is quite long-winded. In earlier days it made some sense
since auto-allocation was a strange concept. But with driver model now
used pretty universally, we can shorten this to 'auto'. This reduces
verbosity and makes it easier to read.

Coincidentally it also ensures that every declaration is on one line,
thus making dtoc's job easier.

Signed-off-by: Simon Glass <sjg@chromium.org>
2020-12-13 08:00:25 -07:00

546 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* STMicroelectronics TPM ST33ZP24 I2C UBOOT driver
*
* Copyright (C) 2016, STMicroelectronics - All Rights Reserved
* Author(s): Christophe Ricard <christophe-h.ricard@st.com> for STMicroelectronics.
*
* Description: Device driver for ST33ZP24 I2C TPM TCG.
*
* This device driver implements the TPM interface as defined in
* the TCG TPM Interface Spec version 1.21, revision 1.0 and the
* STMicroelectronics Protocol Stack Specification version 1.2.0.
*/
#include <common.h>
#include <dm.h>
#include <fdtdec.h>
#include <i2c.h>
#include <log.h>
#include <tpm-v1.h>
#include <errno.h>
#include <linux/delay.h>
#include <linux/types.h>
#include <asm/unaligned.h>
#include "tpm_tis.h"
#include "tpm_internal.h"
#define TPM_ACCESS 0x0
#define TPM_STS 0x18
#define TPM_DATA_FIFO 0x24
#define LOCALITY0 0
#define TPM_DUMMY_BYTE 0xAA
#define TPM_ST33ZP24_I2C_SLAVE_ADDR 0x13
#define TPM_WRITE_DIRECTION 0x80
/*
* st33zp24_i2c_write8_reg
* Send byte to the TIS register according to the ST33ZP24 I2C protocol.
* @param: tpm_register, the tpm tis register where the data should be written
* @param: tpm_data, the tpm_data to write inside the tpm_register
* @param: tpm_size, The length of the data
* @return: Number of byte written successfully else an error code.
*/
static int st33zp24_i2c_write8_reg(struct udevice *dev, u8 tpm_register,
const u8 *tpm_data, size_t tpm_size)
{
struct tpm_chip_priv *chip_priv = dev_get_uclass_priv(dev);
chip_priv->buf[0] = tpm_register;
memcpy(chip_priv->buf + 1, tpm_data, tpm_size);
return dm_i2c_write(dev, 0, chip_priv->buf, tpm_size + 1);
}
/*
* st33zp24_i2c_read8_reg
* Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
* @param: tpm_register, the tpm tis register where the data should be read
* @param: tpm_data, the TPM response
* @param: tpm_size, tpm TPM response size to read.
* @return: Number of byte read successfully else an error code.
*/
static int st33zp24_i2c_read8_reg(struct udevice *dev, u8 tpm_register,
u8 *tpm_data, size_t tpm_size)
{
int status;
u8 data;
data = TPM_DUMMY_BYTE;
status = st33zp24_i2c_write8_reg(dev, tpm_register, &data, 1);
if (status < 0)
return status;
return dm_i2c_read(dev, 0, tpm_data, tpm_size);
}
/*
* st33zp24_i2c_write
* Send byte to the TIS register according to the ST33ZP24 I2C protocol.
* @param: phy_id, the phy description
* @param: tpm_register, the tpm tis register where the data should be written
* @param: tpm_data, the tpm_data to write inside the tpm_register
* @param: tpm_size, the length of the data
* @return: number of byte written successfully: should be one if success.
*/
static int st33zp24_i2c_write(struct udevice *dev, u8 tpm_register,
const u8 *tpm_data, size_t tpm_size)
{
return st33zp24_i2c_write8_reg(dev, tpm_register | TPM_WRITE_DIRECTION,
tpm_data, tpm_size);
}
/*
* st33zp24_i2c_read
* Recv byte from the TIS register according to the ST33ZP24 I2C protocol.
* @param: phy_id, the phy description
* @param: tpm_register, the tpm tis register where the data should be read
* @param: tpm_data, the TPM response
* @param: tpm_size, tpm TPM response size to read.
* @return: number of byte read successfully: should be one if success.
*/
static int st33zp24_i2c_read(struct udevice *dev, u8 tpm_register,
u8 *tpm_data, size_t tpm_size)
{
return st33zp24_i2c_read8_reg(dev, tpm_register, tpm_data, tpm_size);
}
/*
* st33zp24_i2c_release_locality release the active locality
* @param: chip, the tpm chip description.
*/
static void st33zp24_i2c_release_locality(struct udevice *dev)
{
u8 data = TPM_ACCESS_ACTIVE_LOCALITY;
st33zp24_i2c_write(dev, TPM_ACCESS, &data, 1);
}
/*
* st33zp24_i2c_check_locality if the locality is active
* @param: chip, the tpm chip description
* @return: the active locality or -EACCES.
*/
static int st33zp24_i2c_check_locality(struct udevice *dev)
{
struct tpm_chip *chip = dev_get_priv(dev);
u8 data;
u8 status;
status = st33zp24_i2c_read(dev, TPM_ACCESS, &data, 1);
if (!status && (data &
(TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) ==
(TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID))
return chip->locality;
return -EACCES;
}
/*
* st33zp24_i2c_request_locality request the TPM locality
* @param: chip, the chip description
* @return: the active locality or negative value.
*/
static int st33zp24_i2c_request_locality(struct udevice *dev)
{
struct tpm_chip *chip = dev_get_priv(dev);
unsigned long start, stop;
long ret;
u8 data;
if (st33zp24_i2c_check_locality(dev) == chip->locality)
return chip->locality;
data = TPM_ACCESS_REQUEST_USE;
ret = st33zp24_i2c_write(dev, TPM_ACCESS, &data, 1);
if (ret < 0)
return ret;
/* wait for locality activated */
start = get_timer(0);
stop = chip->timeout_a;
do {
if (st33zp24_i2c_check_locality(dev) >= 0)
return chip->locality;
udelay(TPM_TIMEOUT_MS * 1000);
} while (get_timer(start) < stop);
return -EACCES;
}
/*
* st33zp24_i2c_status return the TPM_STS register
* @param: chip, the tpm chip description
* @return: the TPM_STS register value.
*/
static u8 st33zp24_i2c_status(struct udevice *dev)
{
u8 data;
st33zp24_i2c_read(dev, TPM_STS, &data, 1);
return data;
}
/*
* st33zp24_i2c_get_burstcount return the burstcount address 0x19 0x1A
* @param: chip, the chip description
* return: the burstcount or -TPM_DRIVER_ERR in case of error.
*/
static int st33zp24_i2c_get_burstcount(struct udevice *dev)
{
struct tpm_chip *chip = dev_get_priv(dev);
unsigned long start, stop;
int burstcnt, status;
u8 tpm_reg, temp;
/* wait for burstcount */
start = get_timer(0);
stop = chip->timeout_d;
do {
tpm_reg = TPM_STS + 1;
status = st33zp24_i2c_read(dev, tpm_reg, &temp, 1);
if (status < 0)
return -EBUSY;
tpm_reg = TPM_STS + 2;
burstcnt = temp;
status = st33zp24_i2c_read(dev, tpm_reg, &temp, 1);
if (status < 0)
return -EBUSY;
burstcnt |= temp << 8;
if (burstcnt)
return burstcnt;
udelay(TIS_SHORT_TIMEOUT_MS * 1000);
} while (get_timer(start) < stop);
return -EBUSY;
}
/*
* st33zp24_i2c_cancel, cancel the current command execution or
* set STS to COMMAND READY.
* @param: chip, tpm_chip description.
*/
static void st33zp24_i2c_cancel(struct udevice *dev)
{
u8 data;
data = TPM_STS_COMMAND_READY;
st33zp24_i2c_write(dev, TPM_STS, &data, 1);
}
/*
* st33zp24_i2c_wait_for_stat wait for a TPM_STS value
* @param: chip, the tpm chip description
* @param: mask, the value mask to wait
* @param: timeout, the timeout
* @param: status,
* @return: the tpm status, 0 if success, -ETIME if timeout is reached.
*/
static int st33zp24_i2c_wait_for_stat(struct udevice *dev, u8 mask,
unsigned long timeout, int *status)
{
unsigned long start, stop;
/* Check current status */
*status = st33zp24_i2c_status(dev);
if ((*status & mask) == mask)
return 0;
start = get_timer(0);
stop = timeout;
do {
udelay(TPM_TIMEOUT_MS * 1000);
*status = st33zp24_i2c_status(dev);
if ((*status & mask) == mask)
return 0;
} while (get_timer(start) < stop);
return -ETIME;
}
/*
* st33zp24_i2c_recv_data receive data
* @param: chip, the tpm chip description
* @param: buf, the buffer where the data are received
* @param: count, the number of data to receive
* @return: the number of bytes read from TPM FIFO.
*/
static int st33zp24_i2c_recv_data(struct udevice *dev, u8 *buf, size_t count)
{
struct tpm_chip *chip = dev_get_priv(dev);
int size = 0, burstcnt, len, ret, status;
while (size < count &&
st33zp24_i2c_wait_for_stat(dev, TPM_STS_DATA_AVAIL | TPM_STS_VALID,
chip->timeout_c, &status) == 0) {
burstcnt = st33zp24_i2c_get_burstcount(dev);
if (burstcnt < 0)
return burstcnt;
len = min_t(int, burstcnt, count - size);
ret = st33zp24_i2c_read(dev, TPM_DATA_FIFO, buf + size, len);
if (ret < 0)
return ret;
size += len;
}
return size;
}
/*
* st33zp24_i2c_recv received TPM response through TPM phy.
* @param: chip, tpm_chip description.
* @param: buf, the buffer to store data.
* @param: count, the number of bytes that can received (sizeof buf).
* @return: Returns zero in case of success else -EIO.
*/
static int st33zp24_i2c_recv(struct udevice *dev, u8 *buf, size_t count)
{
struct tpm_chip *chip = dev_get_priv(dev);
int size;
unsigned int expected;
if (!chip)
return -ENODEV;
if (count < TPM_HEADER_SIZE) {
size = -EIO;
goto out;
}
size = st33zp24_i2c_recv_data(dev, buf, TPM_HEADER_SIZE);
if (size < TPM_HEADER_SIZE) {
debug("TPM error, unable to read header\n");
goto out;
}
expected = get_unaligned_be32(buf + 2);
if (expected > count || expected < TPM_HEADER_SIZE) {
size = -EIO;
goto out;
}
size += st33zp24_i2c_recv_data(dev, &buf[TPM_HEADER_SIZE],
expected - TPM_HEADER_SIZE);
if (size < expected) {
debug("TPM error, unable to read remaining bytes of result\n");
size = -EIO;
goto out;
}
out:
st33zp24_i2c_cancel(dev);
st33zp24_i2c_release_locality(dev);
return size;
}
/*
* st33zp24_i2c_send send TPM commands through TPM phy.
* @param: chip, tpm_chip description.
* @param: buf, the buffer to send.
* @param: len, the number of bytes to send.
* @return: Returns zero in case of success else the negative error code.
*/
static int st33zp24_i2c_send(struct udevice *dev, const u8 *buf, size_t len)
{
struct tpm_chip *chip = dev_get_priv(dev);
u32 i, size;
int burstcnt, ret, status;
u8 data, tpm_stat;
if (!chip)
return -ENODEV;
if (len < TPM_HEADER_SIZE)
return -EIO;
ret = st33zp24_i2c_request_locality(dev);
if (ret < 0)
return ret;
tpm_stat = st33zp24_i2c_status(dev);
if ((tpm_stat & TPM_STS_COMMAND_READY) == 0) {
st33zp24_i2c_cancel(dev);
if (st33zp24_i2c_wait_for_stat(dev, TPM_STS_COMMAND_READY,
chip->timeout_b, &status) < 0) {
ret = -ETIME;
goto out_err;
}
}
for (i = 0; i < len - 1;) {
burstcnt = st33zp24_i2c_get_burstcount(dev);
if (burstcnt < 0)
return burstcnt;
size = min_t(int, len - i - 1, burstcnt);
ret = st33zp24_i2c_write(dev, TPM_DATA_FIFO, buf + i, size);
if (ret < 0)
goto out_err;
i += size;
}
tpm_stat = st33zp24_i2c_status(dev);
if ((tpm_stat & TPM_STS_DATA_EXPECT) == 0) {
ret = -EIO;
goto out_err;
}
ret = st33zp24_i2c_write(dev, TPM_DATA_FIFO, buf + len - 1, 1);
if (ret < 0)
goto out_err;
tpm_stat = st33zp24_i2c_status(dev);
if ((tpm_stat & TPM_STS_DATA_EXPECT) != 0) {
ret = -EIO;
goto out_err;
}
data = TPM_STS_GO;
ret = st33zp24_i2c_write(dev, TPM_STS, &data, 1);
if (ret < 0)
goto out_err;
return len;
out_err:
st33zp24_i2c_cancel(dev);
st33zp24_i2c_release_locality(dev);
return ret;
}
static int st33zp24_i2c_cleanup(struct udevice *dev)
{
st33zp24_i2c_cancel(dev);
/*
* The TPM needs some time to clean up here,
* so we sleep rather than keeping the bus busy
*/
mdelay(2);
st33zp24_i2c_release_locality(dev);
return 0;
}
static int st33zp24_i2c_init(struct udevice *dev)
{
struct tpm_chip *chip = dev_get_priv(dev);
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;
chip->locality = LOCALITY0;
/*
* A timeout query to TPM can be placed here.
* Standard timeout values are used so far
*/
return 0;
}
static int st33zp24_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 = st33zp24_i2c_init(dev);
if (rc < 0)
chip->is_open = 0;
return rc;
}
static int st33zp24_i2c_close(struct udevice *dev)
{
struct tpm_chip *chip = dev_get_priv(dev);
if (chip->is_open) {
st33zp24_i2c_release_locality(dev);
chip->is_open = 0;
chip->vend_dev = 0;
}
return 0;
}
static int st33zp24_i2c_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",
dev->name,
chip->vend_dev >> 16);
}
static const struct tpm_ops st33zp24_i2c_tpm_ops = {
.open = st33zp24_i2c_open,
.close = st33zp24_i2c_close,
.recv = st33zp24_i2c_recv,
.send = st33zp24_i2c_send,
.cleanup = st33zp24_i2c_cleanup,
.get_desc = st33zp24_i2c_get_desc,
};
static int st33zp24_i2c_probe(struct udevice *dev)
{
struct tpm_chip *chip = dev_get_priv(dev);
/* Default timeouts */
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;
chip->locality = LOCALITY0;
i2c_set_chip_offset_len(dev, 0);
debug("ST33ZP24 I2C TPM from STMicroelectronics found\n");
return 0;
}
static int st33zp24_i2c_remove(struct udevice *dev)
{
st33zp24_i2c_release_locality(dev);
return 0;
}
static const struct udevice_id st33zp24_i2c_ids[] = {
{ .compatible = "st,st33zp24-i2c" },
{ }
};
U_BOOT_DRIVER(st33zp24_i2c) = {
.name = "st33zp24-i2c",
.id = UCLASS_TPM,
.of_match = of_match_ptr(st33zp24_i2c_ids),
.probe = st33zp24_i2c_probe,
.remove = st33zp24_i2c_remove,
.ops = &st33zp24_i2c_tpm_ops,
.priv_auto = sizeof(struct tpm_chip),
};