diff options
Diffstat (limited to 'drivers/tpm/slb9635_i2c/tpm_tis_i2c.c')
| -rw-r--r-- | drivers/tpm/slb9635_i2c/tpm_tis_i2c.c | 624 |
1 files changed, 0 insertions, 624 deletions
diff --git a/drivers/tpm/slb9635_i2c/tpm_tis_i2c.c b/drivers/tpm/slb9635_i2c/tpm_tis_i2c.c deleted file mode 100644 index c2e104189a..0000000000 --- a/drivers/tpm/slb9635_i2c/tpm_tis_i2c.c +++ /dev/null @@ -1,624 +0,0 @@ -/* - * 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 - * - * See file CREDITS for list of people who contributed to this - * project. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation, version 2 of the - * License. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, - * MA 02111-1307 USA - */ - -#include <common.h> -#include <fdtdec.h> -#include <i2c.h> -#include <linux/types.h> - -#include "compatibility.h" -#include "tpm.h" - -DECLARE_GLOBAL_DATA_PTR; - -/* max. buffer size supported by our tpm */ -#ifdef TPM_BUFSIZE -#undef TPM_BUFSIZE -#endif -#define TPM_BUFSIZE 1260 -/* Address of the TPM on the I2C bus */ -#define TPM_I2C_ADDR 0x20 -/* max. number of iterations after i2c NAK */ -#define MAX_COUNT 3 - -#define SLEEP_DURATION 60 /*in usec*/ - -/* max. number of iterations after i2c NAK for 'long' commands - * we need this especially for sending TPM_READY, since the cleanup after the - * transtion to the ready state may take some time, but it is unpredictable - * how long it will take. - */ -#define MAX_COUNT_LONG 50 - -#define SLEEP_DURATION_LONG 210 /* in usec */ - -/* expected value for DIDVID register */ -#define TPM_TIS_I2C_DID_VID_9635 0x000b15d1L -#define TPM_TIS_I2C_DID_VID_9645 0x001a15d1L - -enum i2c_chip_type { - SLB9635, - SLB9645, - UNKNOWN, -}; - -static const char * const chip_name[] = { - [SLB9635] = "slb9635tt", - [SLB9645] = "slb9645tt", - [UNKNOWN] = "unknown/fallback to slb9635", -}; - -/* Structure to store I2C TPM specific stuff */ -struct tpm_inf_dev { - uint addr; - u8 buf[TPM_BUFSIZE + sizeof(u8)]; /* max. buffer size + addr */ - enum i2c_chip_type chip_type; -}; - -static struct tpm_inf_dev tpm_dev = { - .addr = TPM_I2C_ADDR -}; - -/* - * iic_tpm_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. - */ -int iic_tpm_read(u8 addr, u8 *buffer, size_t len) -{ - int rc; - int count; - uint myaddr = addr; - /* we have to use uint here, uchar hangs the board */ - - if ((tpm_dev.chip_type == SLB9635) || (tpm_dev.chip_type == UNKNOWN)) { - /* slb9635 protocol should work in both cases */ - for (count = 0; count < MAX_COUNT; count++) { - rc = i2c_write(tpm_dev.addr, 0, 0, - (uchar *)&myaddr, 1); - if (rc == 0) - break; /* success, break to skip sleep */ - - udelay(SLEEP_DURATION); - } - - 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); - rc = i2c_read(tpm_dev.addr, 0, 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 = i2c_read(tpm_dev.addr, addr, 1, buffer, len); - if (rc == 0) - break; /* break here to skip sleep */ - udelay(SLEEP_DURATION); - } - } - - /* take care of 'guard time' */ - udelay(SLEEP_DURATION); - if (rc) - return -rc; - - return 0; -} - -static int iic_tpm_write_generic(u8 addr, u8 *buffer, size_t len, - unsigned int sleep_time, - u8 max_count) -{ - int rc = 0; - int count; - - /* prepare send buffer */ - tpm_dev.buf[0] = addr; - memcpy(&(tpm_dev.buf[1]), buffer, len); - - for (count = 0; count < max_count; count++) { - rc = i2c_write(tpm_dev.addr, 0, 0, tpm_dev.buf, len + 1); - if (rc == 0) - break; /* success, break to skip sleep */ - - udelay(sleep_time); - } - - /* take care of 'guard time' */ - udelay(SLEEP_DURATION); - if (rc) - return -rc; - - return 0; -} - -/* - * iic_tpm_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 iic_tpm_write_generic function. - * - * Return -EIO on error, 0 on success - */ -static int iic_tpm_write(u8 addr, u8 *buffer, size_t len) -{ - return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION, - MAX_COUNT); -} - -/* - * This function is needed especially for the cleanup situation after - * sending TPM_READY - * */ -static int iic_tpm_write_long(u8 addr, u8 *buffer, size_t len) -{ - return iic_tpm_write_generic(addr, buffer, len, SLEEP_DURATION_LONG, - MAX_COUNT_LONG); -} - -#define TPM_HEADER_SIZE 10 - -enum tis_access { - TPM_ACCESS_VALID = 0x80, - TPM_ACCESS_ACTIVE_LOCALITY = 0x20, - TPM_ACCESS_REQUEST_PENDING = 0x04, - TPM_ACCESS_REQUEST_USE = 0x02, -}; - -enum tis_status { - TPM_STS_VALID = 0x80, - TPM_STS_COMMAND_READY = 0x40, - TPM_STS_GO = 0x20, - TPM_STS_DATA_AVAIL = 0x10, - TPM_STS_DATA_EXPECT = 0x08, -}; - -enum tis_defaults { - TIS_SHORT_TIMEOUT = 750, /* ms */ - TIS_LONG_TIMEOUT = 2000, /* 2 sec */ -}; - -#define TPM_ACCESS(l) (0x0000 | ((l) << 4)) -#define TPM_STS(l) (0x0001 | ((l) << 4)) -#define TPM_DATA_FIFO(l) (0x0005 | ((l) << 4)) -#define TPM_DID_VID(l) (0x0006 | ((l) << 4)) - -static int check_locality(struct tpm_chip *chip, int loc) -{ - u8 buf; - int rc; - - rc = iic_tpm_read(TPM_ACCESS(loc), &buf, 1); - if (rc < 0) - return rc; - - if ((buf & (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) == - (TPM_ACCESS_ACTIVE_LOCALITY | TPM_ACCESS_VALID)) { - chip->vendor.locality = loc; - return loc; - } - - return -1; -} - -static void release_locality(struct tpm_chip *chip, int loc, int force) -{ - u8 buf; - if (iic_tpm_read(TPM_ACCESS(loc), &buf, 1) < 0) - return; - - if (force || (buf & (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) == - (TPM_ACCESS_REQUEST_PENDING | TPM_ACCESS_VALID)) { - buf = TPM_ACCESS_ACTIVE_LOCALITY; - iic_tpm_write(TPM_ACCESS(loc), &buf, 1); - } -} - -static int request_locality(struct tpm_chip *chip, int loc) -{ - unsigned long start, stop; - u8 buf = TPM_ACCESS_REQUEST_USE; - - if (check_locality(chip, loc) >= 0) - return loc; /* we already have the locality */ - - iic_tpm_write(TPM_ACCESS(loc), &buf, 1); - - /* wait for burstcount */ - start = get_timer(0); - stop = chip->vendor.timeout_a; - do { - if (check_locality(chip, loc) >= 0) - return loc; - msleep(TPM_TIMEOUT); - } while (get_timer(start) < stop); - - return -1; -} - -static u8 tpm_tis_i2c_status(struct tpm_chip *chip) -{ - /* NOTE: since i2c read may fail, return 0 in this case --> time-out */ - u8 buf; - if (iic_tpm_read(TPM_STS(chip->vendor.locality), &buf, 1) < 0) - return 0; - else - return buf; -} - -static void tpm_tis_i2c_ready(struct tpm_chip *chip) -{ - /* this causes the current command to be aborted */ - u8 buf = TPM_STS_COMMAND_READY; - iic_tpm_write_long(TPM_STS(chip->vendor.locality), &buf, 1); -} - -static ssize_t get_burstcount(struct tpm_chip *chip) -{ - unsigned long start, stop; - ssize_t burstcnt; - u8 buf[3]; - - /* wait for burstcount */ - /* which timeout value, spec has 2 answers (c & d) */ - start = get_timer(0); - stop = chip->vendor.timeout_d; - do { - /* Note: STS is little endian */ - if (iic_tpm_read(TPM_STS(chip->vendor.locality) + 1, buf, 3) - < 0) - burstcnt = 0; - else - burstcnt = (buf[2] << 16) + (buf[1] << 8) + buf[0]; - - if (burstcnt) - return burstcnt; - msleep(TPM_TIMEOUT); - } while (get_timer(start) < stop); - - return -EBUSY; -} - -static int wait_for_stat(struct tpm_chip *chip, u8 mask, unsigned long timeout, - int *status) -{ - unsigned long start, stop; - - /* check current status */ - *status = tpm_tis_i2c_status(chip); - if ((*status & mask) == mask) - return 0; - - start = get_timer(0); - stop = timeout; - do { - msleep(TPM_TIMEOUT); - *status = tpm_tis_i2c_status(chip); - if ((*status & mask) == mask) - return 0; - - } while (get_timer(start) < stop); - - return -ETIME; -} - -static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count) -{ - size_t size = 0; - ssize_t burstcnt; - int rc; - - while (size < count) { - burstcnt = get_burstcount(chip); - - /* burstcount < 0 = tpm is busy */ - if (burstcnt < 0) - return burstcnt; - - /* limit received data to max. left */ - if (burstcnt > (count - size)) - burstcnt = count - size; - - rc = iic_tpm_read(TPM_DATA_FIFO(chip->vendor.locality), - &(buf[size]), - burstcnt); - if (rc == 0) - size += burstcnt; - } - - return size; -} - -static int tpm_tis_i2c_recv(struct tpm_chip *chip, u8 *buf, size_t count) -{ - int size = 0; - int expected, status; - - if (count < TPM_HEADER_SIZE) { - size = -EIO; - goto out; - } - - /* read first 10 bytes, including tag, paramsize, and result */ - size = recv_data(chip, buf, TPM_HEADER_SIZE); - if (size < TPM_HEADER_SIZE) { - dev_err(chip->dev, "Unable to read header\n"); - goto out; - } - - expected = get_unaligned_be32(buf + TPM_RSP_SIZE_BYTE); - if ((size_t)expected > count) { - size = -EIO; - goto out; - } - - size += recv_data(chip, &buf[TPM_HEADER_SIZE], - expected - TPM_HEADER_SIZE); - if (size < expected) { - dev_err(chip->dev, "Unable to read remainder of result\n"); - size = -ETIME; - goto out; - } - - wait_for_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c, &status); - if (status & TPM_STS_DATA_AVAIL) { /* retry? */ - dev_err(chip->dev, "Error left over data\n"); - size = -EIO; - goto out; - } - -out: - tpm_tis_i2c_ready(chip); - /* The TPM needs some time to clean up here, - * so we sleep rather than keeping the bus busy - */ - udelay(2000); - release_locality(chip, chip->vendor.locality, 0); - - return size; -} - -static int tpm_tis_i2c_send(struct tpm_chip *chip, u8 *buf, size_t len) -{ - int rc, status; - ssize_t burstcnt; - size_t count = 0; - u8 sts = TPM_STS_GO; - - if (len > TPM_BUFSIZE) - return -E2BIG; /* command is too long for our tpm, sorry */ - - if (request_locality(chip, 0) < 0) - return -EBUSY; - - status = tpm_tis_i2c_status(chip); - if ((status & TPM_STS_COMMAND_READY) == 0) { - tpm_tis_i2c_ready(chip); - if (wait_for_stat - (chip, TPM_STS_COMMAND_READY, - chip->vendor.timeout_b, &status) < 0) { - rc = -ETIME; - goto out_err; - } - } - - while (count < len - 1) { - burstcnt = get_burstcount(chip); - - /* burstcount < 0 = tpm is busy */ - if (burstcnt < 0) - return burstcnt; - - if (burstcnt > (len-1-count)) - burstcnt = len-1-count; - -#ifdef CONFIG_TPM_I2C_BURST_LIMITATION - if (burstcnt > CONFIG_TPM_I2C_BURST_LIMITATION) - burstcnt = CONFIG_TPM_I2C_BURST_LIMITATION; -#endif /* CONFIG_TPM_I2C_BURST_LIMITATION */ - - rc = iic_tpm_write(TPM_DATA_FIFO(chip->vendor.locality), - &(buf[count]), burstcnt); - if (rc == 0) - count += burstcnt; - - wait_for_stat(chip, TPM_STS_VALID, - chip->vendor.timeout_c, &status); - - if ((status & TPM_STS_DATA_EXPECT) == 0) { - rc = -EIO; - goto out_err; - } - } - - /* write last byte */ - iic_tpm_write(TPM_DATA_FIFO(chip->vendor.locality), &(buf[count]), 1); - wait_for_stat(chip, TPM_STS_VALID, chip->vendor.timeout_c, &status); - if ((status & TPM_STS_DATA_EXPECT) != 0) { - rc = -EIO; - goto out_err; - } - - /* go and do it */ - iic_tpm_write(TPM_STS(chip->vendor.locality), &sts, 1); - - return len; -out_err: - tpm_tis_i2c_ready(chip); - /* The TPM needs some time to clean up here, - * so we sleep rather than keeping the bus busy - */ - udelay(2000); - release_locality(chip, chip->vendor.locality, 0); - - return rc; -} - -static struct tpm_vendor_specific tpm_tis_i2c = { - .status = tpm_tis_i2c_status, - .recv = tpm_tis_i2c_recv, - .send = tpm_tis_i2c_send, - .cancel = tpm_tis_i2c_ready, - .req_complete_mask = TPM_STS_DATA_AVAIL | TPM_STS_VALID, - .req_complete_val = TPM_STS_DATA_AVAIL | TPM_STS_VALID, - .req_canceled = TPM_STS_COMMAND_READY, -}; - -static enum i2c_chip_type tpm_vendor_chip_type(void) -{ -#ifdef CONFIG_OF_CONTROL - const void *blob = gd->fdt_blob; - - if (fdtdec_next_compatible(blob, 0, COMPAT_INFINEON_SLB9645_TPM) >= 0) - return SLB9645; - - if (fdtdec_next_compatible(blob, 0, COMPAT_INFINEON_SLB9635_TPM) >= 0) - return SLB9635; -#endif - return UNKNOWN; -} - -/* initialisation of i2c tpm */ - - -int tpm_vendor_init(uint32_t dev_addr) -{ - u32 vendor; - u32 expected_did_vid; - uint old_addr; - int rc = 0; - struct tpm_chip *chip; - - old_addr = tpm_dev.addr; - if (dev_addr != 0) - tpm_dev.addr = dev_addr; - - tpm_dev.chip_type = tpm_vendor_chip_type(); - - chip = tpm_register_hardware(&tpm_tis_i2c); - if (chip < 0) { - rc = -ENODEV; - goto out_err; - } - - /* Disable interrupts (not supported) */ - chip->vendor.irq = 0; - - /* Default timeouts */ - chip->vendor.timeout_a = TIS_SHORT_TIMEOUT; - chip->vendor.timeout_b = TIS_LONG_TIMEOUT; - chip->vendor.timeout_c = TIS_SHORT_TIMEOUT; - chip->vendor.timeout_d = TIS_SHORT_TIMEOUT; - - if (request_locality(chip, 0) != 0) { - rc = -ENODEV; - goto out_err; - } - - /* read four bytes from DID_VID register */ - if (iic_tpm_read(TPM_DID_VID(0), (uchar *)&vendor, 4) < 0) { - rc = -EIO; - goto out_release; - } - - if (tpm_dev.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 (tpm_dev.chip_type != UNKNOWN && vendor != expected_did_vid) { - dev_err(dev, "vendor id did not match! ID was %08x\n", vendor); - rc = -ENODEV; - goto out_release; - } - - dev_info(dev, "1.2 TPM (chip type %s device-id 0x%X)\n", - chip_name[tpm_dev.chip_type], vendor >> 16); - - /* - * A timeout query to TPM can be placed here. - * Standard timeout values are used so far - */ - - return 0; - -out_release: - release_locality(chip, 0, 1); - -out_err: - tpm_dev.addr = old_addr; - return rc; -} - -void tpm_vendor_cleanup(struct tpm_chip *chip) -{ - release_locality(chip, chip->vendor.locality, 1); -} |