[U-Boot] [PATCH v3 1/2] Introduce generic TPM support in u-boot

Vadim Bendebury vbendeb at chromium.org
Sun Oct 16 03:20:11 CEST 2011


On Sat, Oct 15, 2011 at 6:13 PM, Vadim Bendebury <vbendeb at chromium.org> wrote:
> TPM (Trusted Platform Module) is an integrated circuit and
> software platform that provides computer manufacturers with the
> core components of a subsystem used to assure authenticity,
> integrity and confidentiality.
>
> This driver supports version 1.2 of the TCG (Trusted Computing
> Group) specifications.
>
> The TCG specification defines several so called localities in a
> TPM chip, to be controlled by different software layers. When
> used on a typical x86 platform during the firmware phase, only
> locality 0 can be accessed by the CPU, so this driver even while
> supporting the locality concept presumes that only locality zero
> is used.
>
> This implementation is loosely based on the article "Writing a
> TPM Device Driver" published on http://ptgmedia.pearsoncmg.com
>
> Compiling this driver with DEBUG defined will generate trace of
> all accesses to TMP registers.
>
> This driver has been tested and is being used in three different
> functional ChromeOS machines (Pinetrail and Sandy Bridge Intel
> chipsets) all using the same Infineon SLB 9635 TT 1.2 device.
>
> A u-boot cli command allowing access to the TPM was also
> implemented and is being submitted as a second patch.
>
> Change-Id: I22a33c3e5b2e20eec9557a7621bd463b30389d73
> Signed-off-by: Vadim Bendebury <vbendeb at chromium.org>
> CC: Wolfgang Denk <wd at denx.de>
> ---
>  Makefile                      |    3 +
>  README                        |   10 +
>  drivers/tpm/Makefile          |   43 ++++
>  drivers/tpm/generic_lpc_tpm.c |  485 +++++++++++++++++++++++++++++++++++++++++
>  include/tpm.h                 |   71 ++++++
>  5 files changed, 612 insertions(+), 0 deletions(-)
>  create mode 100644 drivers/tpm/Makefile
>  create mode 100644 drivers/tpm/generic_lpc_tpm.c
>  create mode 100644 include/tpm.h
>
> diff --git a/Makefile b/Makefile
> index 5db2e0e..df86088 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -268,6 +268,9 @@ LIBS += arch/powerpc/cpu/mpc8xxx/lib8xxx.o
>  endif
>  LIBS += drivers/rtc/librtc.o
>  LIBS += drivers/serial/libserial.o
> +ifeq ($(CONFIG_GENERIC_LPC_TPM),y)
> +LIBS += drivers/tpm/libtpm.o
> +endif
>  LIBS += drivers/twserial/libtws.o
>  LIBS += drivers/usb/eth/libusb_eth.o
>  LIBS += drivers/usb/gadget/libusb_gadget.o
> diff --git a/README b/README
> index 7e032a9..bcd3695 100644
> --- a/README
> +++ b/README
> @@ -1018,6 +1018,16 @@ The following options need to be configured:
>                        CONFIG_SH_ETHER_CACHE_WRITEBACK
>                        If this option is set, the driver enables cache flush.
>
> +- TPM Support:
> +               CONFIG_GENERIC_LPC_TPM
> +               Support for generic parallel port TPM devices. Only one device
> +               per system is supported at this time.
> +
> +                       CONFIG_TPM_TIS_BASE_ADDRESS
> +                       Base address where the generic TPM device is mapped
> +                       to. Contemporary x86 systems usually map it at
> +                       0xfed40000.
> +
>  - USB Support:
>                At the moment only the UHCI host controller is
>                supported (PIP405, MIP405, MPC5200); define
> diff --git a/drivers/tpm/Makefile b/drivers/tpm/Makefile
> new file mode 100644
> index 0000000..be11c8b
> --- /dev/null
> +++ b/drivers/tpm/Makefile
> @@ -0,0 +1,43 @@
> +# Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
> +#
> +# 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; either version 2 of
> +# the License, or (at your option) any later version.
> +#
> +# 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 $(TOPDIR)/config.mk
> +
> +LIB := $(obj)libtpm.o
> +
> +COBJS-$(CONFIG_GENERIC_LPC_TPM) = generic_lpc_tpm.o
> +
> +COBJS  := $(COBJS-y)
> +SRCS   := $(COBJS:.o=.c)
> +OBJS   := $(addprefix $(obj),$(COBJS))
> +
> +all:   $(LIB)
> +
> +$(LIB): $(obj).depend $(OBJS)
> +       $(call cmd_link_o_target, $(OBJS))
> +
> +#########################################################################
> +
> +include $(SRCTREE)/rules.mk
> +
> +sinclude $(obj).depend
> +
> +#########################################################################
> diff --git a/drivers/tpm/generic_lpc_tpm.c b/drivers/tpm/generic_lpc_tpm.c
> new file mode 100644
> index 0000000..6b58420
> --- /dev/null
> +++ b/drivers/tpm/generic_lpc_tpm.c
> @@ -0,0 +1,485 @@
> +/*
> + * Copyright (c) 2011 The Chromium OS Authors.
> + *
> + * 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; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * 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
> + */
> +
> +/*
> + * The code in this file is based on the article "Writing a TPM Device Driver"
> + * published on http://ptgmedia.pearsoncmg.com.
> + *
> + * One principal difference is that in the simplest config the other than 0
> + * TPM localities do not get mapped by some devices (for instance, by Infineon
> + * slb9635), so this driver provides access to locality 0 only.
> + */
> +
> +#include <common.h>
> +#include <asm/io.h>
> +#include <tpm.h>
> +
> +#define PREFIX "lpc_tpm: "
> +
> +#define TPM_TOTAL_LOCALITIES   5
> +struct tpm_locality {
> +       u32 access;
> +       u8 padding0[4];
> +       u32 int_enable;
> +       u8 vector;
> +       u8 padding1[3];
> +       u32 int_status;
> +       u32 int_capability;
> +       u32 tpm_status;
> +       u8 padding2[8];
> +       u8 data;
> +       u8 padding3[3803];
> +       u32 did_vid;
> +       u8 rid;
> +       u8 padding4[251];
> +};
> +
> +struct lpc_tpm {
> +       struct tpm_locality locality[TPM_TOTAL_LOCALITIES];
> +};
> +
> +static struct lpc_tpm *lpc_tpm_dev =
> +       (struct lpc_tpm *)CONFIG_TPM_TIS_BASE_ADDRESS;
> +
> +/* Some registers' bit field definitions */
> +#define TIS_STS_VALID                  (1 << 7) /* 0x80 */
> +#define TIS_STS_COMMAND_READY          (1 << 6) /* 0x40 */
> +#define TIS_STS_TPM_GO                 (1 << 5) /* 0x20 */
> +#define TIS_STS_DATA_AVAILABLE         (1 << 4) /* 0x10 */
> +#define TIS_STS_EXPECT                 (1 << 3) /* 0x08 */
> +#define TIS_STS_RESPONSE_RETRY         (1 << 1) /* 0x02 */
> +
> +#define TIS_ACCESS_TPM_REG_VALID_STS   (1 << 7) /* 0x80 */
> +#define TIS_ACCESS_ACTIVE_LOCALITY     (1 << 5) /* 0x20 */
> +#define TIS_ACCESS_BEEN_SEIZED         (1 << 4) /* 0x10 */
> +#define TIS_ACCESS_SEIZE               (1 << 3) /* 0x08 */
> +#define TIS_ACCESS_PENDING_REQUEST     (1 << 2) /* 0x04 */
> +#define TIS_ACCESS_REQUEST_USE         (1 << 1) /* 0x02 */
> +#define TIS_ACCESS_TPM_ESTABLISHMENT   (1 << 0) /* 0x01 */
> +
> +#define TIS_STS_BURST_COUNT_MASK       (0xffff)
> +#define TIS_STS_BURST_COUNT_SHIFT      (8)
> +
> +/*
> + * Error value returned if a tpm register does not enter the expected state
> + * after continuous polling. No actual TPM register reading ever returns -1,
> + * so this value is a safe error indication to be mixed with possible status
> + * register values.
> + */
> +#define TPM_TIMEOUT_ERR                        (-1)
> +
> +/* Error value returned on various TPM driver errors. */
> +#define TPM_DRIVER_ERR         (1)
> +
> + /* 1 second is plenty for anything TPM does. */
> +#define MAX_DELAY_US   (1000 * 1000)
> +
> +/* Retrieve burst count value out of the status register contents. */
> +#define BURST_COUNT(status) ((u16)(((status) >> TIS_STS_BURST_COUNT_SHIFT) & \
> +                                  TIS_STS_BURST_COUNT_MASK))
> +
> +/*
> + * Structures defined below allow creating descriptions of TPM vendor/device
> + * ID information for run time discovery. The only device the system knows
> + * about at this time is Infineon slb9635.
> + */
> +struct device_name {
> +       u16 dev_id;
> +       const char * const dev_name;
> +};
> +
> +struct vendor_name {
> +       u16 vendor_id;
> +       const char *vendor_name;
> +       const struct device_name *dev_names;
> +};
> +
> +static const struct device_name infineon_devices[] = {
> +       {0xb, "SLB9635 TT 1.2"},
> +       {0}
> +};
> +
> +static const struct vendor_name vendor_names[] = {
> +       {0x15d1, "Infineon", infineon_devices},
> +};
> +
> +/*
> + * Cached vendor/device ID pair to indicate that the device has been already
> + * discovered.
> + */
> +static u32 vendor_dev_id;
> +
> +/* TPM access going through macros to make tracing easier. */
> +#define tpm_read(ptr) ({ \
> +       u32  __ret; \
> +       __ret = (sizeof(*ptr) == 1) ? readb(ptr) : readl(ptr); \
> +       debug(PREFIX "Read reg 0x%x returns 0x%x\n", \
> +             (u32)ptr - (u32)lpc_tpm_dev, __ret); \
> +       __ret; })
> +
> +#define tpm_write(value, ptr) do { \
> +       u32 __v = value; \
> +       debug(PREFIX "Write reg 0x%x with 0x%x\n", \
> +              (u32)ptr - (u32)lpc_tpm_dev, __v); \
> +       if (sizeof(*ptr) == 1) \
> +               writeb(__v, ptr); \
> +       else \
> +               writel(__v, ptr); } \
> +       while (0)
> +
> +/*
> + * tis_wait_reg()
> + *
> + * Wait for at least a second for a register to change its state to match the
> + * expected state. Normally the transition happens within microseconds.
> + *
> + * @reg - the TPM register offset
> + * @locality - locality
> + * @mask - bitmask for the bitfield(s) to watch
> + * @expected - value the field(s) are supposed to be set to
> + *
> + * Returns the register contents in case the expected value was found in the
> + * appropriate register bits, or TPM_TIMEOUT_ERR on timeout.
> + */
> +static u32 tis_wait_reg(u32 *reg, u8 mask, u8 expected)
> +{
> +       u32 time_us = MAX_DELAY_US;
> +
> +       while (time_us > 0) {
> +               u32 value = tpm_read(reg);
> +               if ((value & mask) == expected)
> +                       return value;
> +               udelay(1); /* 1 us */
> +               time_us--;
> +       }
> +       return TPM_TIMEOUT_ERR;
> +}
> +
> +/*
> + * Probe the TPM device and try determining its manufacturer/device name.
> + *
> + * Returns 0 on success (the device is found or was found during an earlier
> + * invocation) or TPM_DRIVER_ERR if the device is not found.
> + */
> +int tis_init(void)
> +{
> +       u32 didvid = tpm_read(&lpc_tpm_dev->locality[0].did_vid);
> +       int i;
> +       const char *device_name = "unknown";
> +       const char *vendor_name = device_name;
> +       u16 vid, did;
> +
> +       if (vendor_dev_id)
> +               return 0;  /* Already probed. */
> +
> +       if (!didvid || (didvid == 0xffffffff)) {
> +               printf("%s: No TPM device found\n", __func__);
> +               return TPM_DRIVER_ERR;
> +       }
> +
> +       vendor_dev_id = didvid;
> +
> +       vid = didvid & 0xffff;
> +       did = (didvid >> 16) & 0xffff;
> +       for (i = 0; i < ARRAY_SIZE(vendor_names); i++) {
> +               int j = 0;
> +               u16 known_did;
> +
> +               if (vid == vendor_names[i].vendor_id)
> +                       vendor_name = vendor_names[i].vendor_name;
> +
> +               while ((known_did = vendor_names[i].dev_names[j].dev_id) != 0) {
> +                       if (known_did == did) {
> +                               device_name =
> +                                       vendor_names[i].dev_names[j].dev_name;
> +                               break;
> +                       }
> +                       j++;
> +               }
> +               break;
> +       }
> +
> +       printf("Found TPM %s by %s\n", device_name, vendor_name);
> +       return 0;
> +}
> +
> +/*
> + * tis_senddata()
> + *
> + * send the passed in data to the TPM device.
> + *
> + * @data - address of the data to send, byte by byte
> + * @len - length of the data to send
> + *
> + * Returns 0 on success, TPM_DRIVER_ERR on error (in case the device does
> + * not accept the entire command).
> + */
> +static u32 tis_senddata(const u8 * const data, u32 len)
> +{
> +       u32 offset = 0;
> +       u16 burst = 0;
> +       u32 max_cycles = 0;
> +       u8 locality = 0;
> +       u32 value;
> +
> +       value = tis_wait_reg(&lpc_tpm_dev->locality[locality].tpm_status,
> +                            TIS_STS_COMMAND_READY, TIS_STS_COMMAND_READY);
> +       if (value == TPM_TIMEOUT_ERR) {
> +               printf("%s:%d - failed to get 'command_ready' status\n",
> +                      __FILE__, __LINE__);
> +               return TPM_DRIVER_ERR;
> +       }
> +       burst = BURST_COUNT(value);
> +
> +       while (1) {
> +               unsigned count;
> +
> +               /* Wait till the device is ready to accept more data. */
> +               while (!burst) {
> +                       if (max_cycles++ == MAX_DELAY_US) {
> +                               printf("%s:%d failed to feed %d bytes of %d\n",
> +                                      __FILE__, __LINE__, len - offset, len);
> +                               return TPM_DRIVER_ERR;
> +                       }
> +                       udelay(1);
> +                       burst = BURST_COUNT(tpm_read(&lpc_tpm_dev->locality
> +                                                    [locality].tpm_status));
> +               }
> +
> +               max_cycles = 0;
> +
> +               /*
> +                * Calculate number of bytes the TPM is ready to accept in one
> +                * shot.
> +                *
> +                * We want to send the last byte outside of the loop (hence
> +                * the -1 below) to make sure that the 'expected' status bit
> +                * changes to zero exactly after the last byte is fed into the
> +                * FIFO.
> +                */
> +               count = min(burst, len - offset - 1);
> +               while (count--)
> +                       tpm_write(data[offset++],
> +                                 &lpc_tpm_dev->locality[locality].data);
> +
> +               value = tis_wait_reg(&lpc_tpm_dev->locality
> +                                    [locality].tpm_status,
> +                                    TIS_STS_VALID, TIS_STS_VALID);
> +
> +               if ((value == TPM_TIMEOUT_ERR) || !(value & TIS_STS_EXPECT)) {
> +                       printf("%s:%d TPM command feed overflow\n",
> +                              __FILE__, __LINE__);
> +                       return TPM_DRIVER_ERR;
> +               }
> +
> +               burst = BURST_COUNT(value);
> +               if ((offset == (len - 1)) && burst) {
> +                       /*
> +                        * We need to be able to send the last byte to the
> +                        * device, so burst size must be nonzero before we
> +                        * break out.
> +                        */
> +                       break;
> +               }
> +       }
> +
> +       /* Send the last byte. */
> +       tpm_write(data[offset++], &lpc_tpm_dev->locality[locality].data);
> +       /*
> +        * Verify that TPM does not expect any more data as part of this
> +        * command.
> +        */
> +       value = tis_wait_reg(&lpc_tpm_dev->locality[locality].tpm_status,
> +                            TIS_STS_VALID, TIS_STS_VALID);
> +       if ((value == TPM_TIMEOUT_ERR) || (value & TIS_STS_EXPECT)) {
> +               printf("%s:%d unexpected TPM status 0x%x\n",
> +                      __FILE__, __LINE__, value);
> +               return TPM_DRIVER_ERR;
> +       }
> +
> +       /* OK, sitting pretty, let's start the command execution. */
> +       tpm_write(TIS_STS_TPM_GO, &lpc_tpm_dev->locality[locality].tpm_status);
> +       return 0;
> +}
> +
> +/*
> + * tis_readresponse()
> + *
> + * read the TPM device response after a command was issued.
> + *
> + * @buffer - address where to read the response, byte by byte.
> + * @len - pointer to the size of buffer
> + *
> + * On success stores the number of received bytes to len and returns 0. On
> + * errors (misformatted TPM data or synchronization problems) returns
> + * TPM_DRIVER_ERR.
> + */
> +static u32 tis_readresponse(u8 *buffer, u32 *len)
> +{
> +       u16 burst_count;
> +       u32 value;
> +       u32 offset = 0;
> +       u8 locality = 0;
> +       const u32 has_data = TIS_STS_DATA_AVAILABLE | TIS_STS_VALID;
> +       u32 expected_count = *len;
> +       int max_cycles = 0;
> +
> +       /* Wait for the TPM to process the command. */
> +       value = tis_wait_reg(&lpc_tpm_dev->locality[locality].tpm_status,
> +                             has_data, has_data);
> +       if (value == TPM_TIMEOUT_ERR) {
> +               printf("%s:%d failed processing command\n",
> +                      __FILE__, __LINE__);
> +               return TPM_DRIVER_ERR;
> +       }
> +
> +       do {
> +               while ((burst_count = BURST_COUNT(value)) == 0) {
> +                       if (max_cycles++ == MAX_DELAY_US) {
> +                               printf("%s:%d TPM stuck on read\n",
> +                                      __FILE__, __LINE__);
> +                               return TPM_DRIVER_ERR;
> +                       }
> +                       udelay(1);
> +                       value = tpm_read(&lpc_tpm_dev->locality
> +                                         [locality].tpm_status);
> +               }
> +
> +               max_cycles = 0;
> +
> +               while (burst_count-- && (offset < expected_count)) {
> +                       buffer[offset++] = (u8) tpm_read(&lpc_tpm_dev->locality
> +                                                        [locality].data);
> +
> +                       if (offset == 6) {
> +                               /*
> +                                * We got the first six bytes of the reply,
> +                                * let's figure out how many bytes to expect
> +                                * total - it is stored as a 4 byte number in
> +                                * network order, starting with offset 2 into
> +                                * the body of the reply.
> +                                */
> +                               u32 real_length;
> +                               memcpy(&real_length,
> +                                      buffer + 2,
> +                                      sizeof(real_length));
> +                               expected_count = be32_to_cpu(real_length);
> +
> +                               if ((expected_count < offset) ||
> +                                   (expected_count > *len)) {
> +                                       printf("%s:%d bad response size %d\n",
> +                                              __FILE__, __LINE__,
> +                                              expected_count);
> +                                       return TPM_DRIVER_ERR;
> +                               }
> +                       }
> +               }
> +
> +               /* Wait for the next portion. */
> +               value = tis_wait_reg(&lpc_tpm_dev->locality
> +                                     [locality].tpm_status,
> +                                     TIS_STS_VALID, TIS_STS_VALID);
> +               if (value == TPM_TIMEOUT_ERR) {
> +                       printf("%s:%d failed to read response\n",
> +                              __FILE__, __LINE__);
> +                       return TPM_DRIVER_ERR;
> +               }
> +
> +               if (offset == expected_count)
> +                       break;  /* We got all we needed. */
> +
> +       } while ((value & has_data) == has_data);
> +
> +       /*
> +        * Make sure we indeed read all there was. The TIS_STS_VALID bit is
> +        * known to be set.
> +        */
> +       if (value & TIS_STS_DATA_AVAILABLE) {
> +               printf("%s:%d wrong receive status %x\n",
> +                      __FILE__, __LINE__, value);
> +               return TPM_DRIVER_ERR;
> +       }
> +
> +       /* Tell the TPM that we are done. */
> +       tpm_write(TIS_STS_COMMAND_READY, &lpc_tpm_dev->locality
> +                 [locality].tpm_status);
> +       *len = offset;
> +       return 0;
> +}
> +
> +int tis_open(void)
> +{
> +       u8 locality = 0; /* we use locality zero for everything. */
> +
> +       if (tis_close())
> +               return TPM_DRIVER_ERR;
> +
> +       /* now request access to locality. */
> +       tpm_write(TIS_ACCESS_REQUEST_USE,
> +                 &lpc_tpm_dev->locality[locality].access);
> +
> +
> +       /* did we get a lock? */
> +       if (tis_wait_reg(&lpc_tpm_dev->locality[locality].access,
> +                        TIS_ACCESS_ACTIVE_LOCALITY,
> +                        TIS_ACCESS_ACTIVE_LOCALITY) == TPM_TIMEOUT_ERR) {
> +               printf("%s:%d - failed to lock locality %d\n",
> +                      __FILE__, __LINE__, locality);
> +               return TPM_DRIVER_ERR;
> +       }
> +
> +       tpm_write(TIS_STS_COMMAND_READY,
> +                 &lpc_tpm_dev->locality[locality].tpm_status);
> +       return 0;
> +}
> +
> +int tis_close(void)
> +{
> +       u8 locality = 0;
> +
> +       if (tpm_read(&lpc_tpm_dev->locality[locality].access) &
> +           TIS_ACCESS_ACTIVE_LOCALITY) {
> +               tpm_write(TIS_ACCESS_ACTIVE_LOCALITY,
> +                         &lpc_tpm_dev->locality[locality].access);
> +
> +               if (tis_wait_reg(&lpc_tpm_dev->locality[locality].access,
> +                                TIS_ACCESS_ACTIVE_LOCALITY, 0) ==
> +                   TPM_TIMEOUT_ERR) {
> +                       printf("%s:%d - failed to release locality %d\n",
> +                              __FILE__, __LINE__, locality);
> +                       return TPM_DRIVER_ERR;
> +               }
> +       }
> +       return 0;
> +}
> +
> +int tis_sendrecv(const u8 *sendbuf, size_t send_size,
> +                u8 *recvbuf, size_t *recv_len)
> +{
> +       if (tis_senddata(sendbuf, send_size)) {
> +               printf("%s:%d failed sending data to TPM\n",
> +                      __FILE__, __LINE__);
> +               return TPM_DRIVER_ERR;
> +       }
> +
> +       return tis_readresponse(recvbuf, recv_len);
> +}
> diff --git a/include/tpm.h b/include/tpm.h
> new file mode 100644
> index 0000000..6b21e9c
> --- /dev/null
> +++ b/include/tpm.h
> @@ -0,0 +1,71 @@
> +/*
> + * Copyright (c) 2011 The Chromium OS Authors.
> + *
> + * 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; either version 2 of
> + * the License, or (at your option) any later version.
> + *
> + * 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
> + */
> +
> +#ifndef _INCLUDE_TPM_H_
> +#define _INCLUDE_TPM_H_
> +
> +#include <common.h>
> +
> +/*
> + * tis_init()
> + *
> + * Initialize the TPM device. Returns 0 on success or -1 on
> + * failure (in case device probing did not succeed).
> + */
> +int tis_init(void);
> +
> +/*
> + * tis_open()
> + *
> + * Requests access to locality 0 for the caller. After all commands have been
> + * completed the caller is supposed to call tis_close().
> + *
> + * Returns 0 on success, -1 on failure.
> + */
> +int tis_open(void);
> +
> +/*
> + * tis_close()
> + *
> + * terminate the currect session with the TPM by releasing the locked
> + * locality. Returns 0 on success of -1 on failure (in case lock
> + * removal did not succeed).
> + */
> +int tis_close(void);
> +
> +/*
> + * tis_sendrecv()
> + *
> + * Send the requested data to the TPM and then try to get its response
> + *
> + * @sendbuf - buffer of the data to send
> + * @send_size size of the data to send
> + * @recvbuf - memory to save the response to
> + * @recv_len - pointer to the size of the response buffer
> + *
> + * Returns 0 on success (and places the number of response bytes at recv_len)
> + * or -1 on failure.
> + */
> +int tis_sendrecv(const uint8_t *sendbuf, size_t send_size, uint8_t *recvbuf,
> +                       size_t *recv_len);
> +
> +#endif /* _INCLUDE_TPM_H_ */
> --
> 1.7.3.1
>
>

sorry, sent this and the other patchset with a wrong version number,
will resend with the correct number.

BTW, here one can see the differences between v2 and v3
http://review-t.appspot.com/23001 and
http://review-t.appspot.com/24001.

Among other things this app allows adding comments while reviewing the
diffs (just doubleclick on the side by side diffs page).

Has it been ever discussed - setting up a tool like this for u-boot?

cheers,
/vb


More information about the U-Boot mailing list