commit a2087649ca68f259e980594f536ea3ff19c4bbe3
author Jerome Forissier <jerome@forissier.org> Wed Sep 18 18:03:43 2019 +0200
committer Jérôme Forissier <jerome@forissier.org> Mon Sep 30 09:44:47 2019 +0200
tree fb48c9551efa982906e5961bfb5b1d910bbf183f
parent dfb96021b49bf16f050fead3a9cea46f071b1bc4

core: add support for dumping build configuration info on boot

During development, we occasionally experience crashes within the TEE
core. When the tests are run locally, the developer has all the needed
information to troubleshoot the issue. But when the crash occurs on a
remote host (CI for instance), it is sometimes inconvenient or even
impossible to retrieve files other than the console logs. As a result,
it is equally inconvenient or impossible to obtain a symbolized crash
dump (scripts/symbolize.py needs the dump message but also tee.elf).
If the exact build configuration is known, then it is possible to
reproduce the build locally (assuming the same toolchain is also used
which is not a problem in practice) and proceed with debugging.
Unfortunately the values of the CFG_ flags are not always shown in the
logs and omitting only one flag can significantly change the TEE
binary.

This commit introduces CFG_SHOW_CONF_ON_BOOT (default n). When enabled,
the contents of the build configuration file $O/conf.mk is printed
to the secure console during initialization with TRACE_INFO severity.
The file is compressed to reduce memory usage and space used in the
logs, and it is encoded into printable text.

To obtain the conf.mk file, one needs to copy and paste the encoded
text into 'base64 -d | xz -d'. These two commands are also required at
build time when CFG_SHOW_CONF_ON_BOOT is y.

Signed-off-by: Jerome Forissier <jerome@forissier.org>
Reviewed-by: Joakim Bech <joakim.bech@linaro.org>
Reviewed-by: Jens Wiklander <jens.wiklander@linaro.org>