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Aaron Durbin eeb77379e0 vboot/tpm2: enable nvmem commits on cr50 when writing firmware secdata
cr50 by default delays nvmem commits internally from the point of
reset to accumulate change state. However, the factory process can
put a board into dev mode through the recovery screen. This state
is stored in the TPM's nvmem space. When the factory process is
complete a disable_dev_request and battery_cutoff_request is performed.
This leads to disabling the dev mode in TPM, but the battery is
subsequently cut off so the nvmem contents never stick. Therefore,
whenever antirollback_write_space_firmware() is called we know there
was a change in secdata so request cr50 to immediately enable nvmem
commits going forward. This allows state changes to happen immediately.

The fallout from this is that when secdata is changed that current
boot will take longer because every transaction that writes to TPM
nvmem space will perform a write synchronously. All subsequent boots
do not have that effect.

It should also be noted that this approach to the implementation is
a pretty severe layering violation. However, the current TPM APIs
don't lend themselves well to extending commands or re-using code
outside of the current routines which inherently assume all knowledge
of every command (in conflict with vendor commands since those are
vendor-specific by definition).

BUG=b:35775104
BRANCH=reef
TEST=Confirmed disablement of dev mode sticks in the presence of:
crossystem disable_dev_request=1; crossystem
battery_cutoff_request=1; reboot;

Change-Id: I3395db9cbdfea45da1f5cb994c6570978593b944
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/18681
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Tested-by: build bot (Jenkins)
2017-03-09 19:15:03 +01:00
3rdparty 3rdparty: update arm-trusted-firmware submodule 2017-01-12 18:38:26 +01:00
Documentation arch/x86/acpigen: Provide helper functions for enabling/disabling GPIO 2017-02-22 22:19:29 +01:00
configs configs/builder: Remove pre-defined VGA bios file 2017-01-20 17:37:19 +01:00
payloads libpayload-x86: Enable SSE and FPU when present 2017-03-08 04:44:12 +01:00
src vboot/tpm2: enable nvmem commits on cr50 when writing firmware secdata 2017-03-09 19:15:03 +01:00
util toolchain: fix compilation of GMP on FreeBSD 2017-03-09 12:15:56 +01:00
.checkpatch.conf checkpatch.conf: Update rules 2017-03-09 04:37:28 +01:00
.clang-format
.gitignore .gitignore: Add autoport binary 2017-03-02 22:03:28 +01:00
.gitmodules Set up 3rdparty/libgfxinit 2016-10-29 01:35:03 +02:00
.gitreview
COPYING
MAINTAINERS MAINTAINERS: Update list 2017-03-08 04:33:30 +01:00
Makefile build system: mark sub-make invocations as parallelizable 2017-01-31 18:51:55 +01:00
Makefile.inc build system: mark sub-make invocations as parallelizable 2017-01-31 18:51:55 +01:00
README Remove extra newlines from the end of all coreboot files. 2016-07-31 18:19:33 +02:00
gnat.adc gnat.adc: Do not generate assertion code for Refined_Post 2016-10-29 01:33:31 +02:00
toolchain.inc Add minimal GNAT run time system (RTS) 2016-09-19 11:14:49 +02:00

README

-------------------------------------------------------------------------------
coreboot README
-------------------------------------------------------------------------------

coreboot is a Free Software project aimed at replacing the proprietary BIOS
(firmware) found in most computers.  coreboot performs a little bit of
hardware initialization and then executes additional boot logic, called a
payload.

With the separation of hardware initialization and later boot logic,
coreboot can scale from specialized applications that run directly
firmware, run operating systems in flash, load custom
bootloaders, or implement firmware standards, like PC BIOS services or
UEFI. This allows for systems to only include the features necessary
in the target application, reducing the amount of code and flash space
required.

coreboot was formerly known as LinuxBIOS.


Payloads
--------

After the basic initialization of the hardware has been performed, any
desired "payload" can be started by coreboot.

See http://www.coreboot.org/Payloads for a list of supported payloads.


Supported Hardware
------------------

coreboot supports a wide range of chipsets, devices, and mainboards.

For details please consult:

 * http://www.coreboot.org/Supported_Motherboards
 * http://www.coreboot.org/Supported_Chipsets_and_Devices


Build Requirements
------------------

 * make
 * gcc / g++
   Because Linux distribution compilers tend to use lots of patches. coreboot
   does lots of "unusual" things in its build system, some of which break due
   to those patches, sometimes by gcc aborting, sometimes - and that's worse -
   by generating broken object code.
   Two options: use our toolchain (eg. make crosstools-i386) or enable the
   ANY_TOOLCHAIN Kconfig option if you're feeling lucky (no support in this
   case).
 * iasl (for targets with ACPI support)

Optional:

 * doxygen (for generating/viewing documentation)
 * gdb (for better debugging facilities on some targets)
 * ncurses (for 'make menuconfig' and 'make nconfig')
 * flex and bison (for regenerating parsers)


Building coreboot
-----------------

Please consult http://www.coreboot.org/Build_HOWTO for details.


Testing coreboot Without Modifying Your Hardware
------------------------------------------------

If you want to test coreboot without any risks before you really decide
to use it on your hardware, you can use the QEMU system emulator to run
coreboot virtually in QEMU.

Please see http://www.coreboot.org/QEMU for details.


Website and Mailing List
------------------------

Further details on the project, a FAQ, many HOWTOs, news, development
guidelines and more can be found on the coreboot website:

  http://www.coreboot.org

You can contact us directly on the coreboot mailing list:

  http://www.coreboot.org/Mailinglist


Copyright and License
---------------------

The copyright on coreboot is owned by quite a large number of individual
developers and companies. Please check the individual source files for details.

coreboot is licensed under the terms of the GNU General Public License (GPL).
Some files are licensed under the "GPL (version 2, or any later version)",
and some files are licensed under the "GPL, version 2". For some parts, which
were derived from other projects, other (GPL-compatible) licenses may apply.
Please check the individual source files for details.

This makes the resulting coreboot images licensed under the GPL, version 2.