First look for firmware files in the source directory and then, if not
found, look for them in locations where Debian installs them. Prefer to
use the unified firmware file and, if not found, use the pflash firmware
files split in to code and variables. By looking for files in the source
directory first, system firmware files can be overridden and it can be
ensured that the tests can be run regardless of the distro or where the
system firmware files are stored. If no firmware files are found, print
an error message and exit with error.
If a firmware VARS file is found, use it with snapshot mode enabled, which
makes the VARS writable to the virtual machine, but does not write back
the changes to the file. This allows using the readonly system VARS file
without copying it or using it in readonly mode, which causes the ARM
machine to fail. This also gives tests effectively their own ephemeral VARS
file that can be written to without causing side-effects for other tests.
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>