[coreboot-gerrit] Patch merged into coreboot/master: vboot/tpm2: enable nvmem commits on cr50 when writing firmware secdata

[gerrit at coreboot.org]

the following patch was just integrated into master:
commit eeb77379e03d868a52d42cd4f0dfba8d11c3d337
Author: Aaron Durbin <adurbin at chromium.org>
Date:   Wed Mar 8 11:23:11 2017 -0600

    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 at chromium.org>
    Reviewed-on: https://review.coreboot.org/18681
    Reviewed-by: Duncan Laurie <dlaurie at chromium.org>
    Tested-by: build bot (Jenkins)


See https://review.coreboot.org/18681 for details.

-gerrit