CROSS_COMPILE := aarch64-linux-gnu-
output_dir := $(PWD)/../bin
-makejobs := $(shell grep '^processor' /proc/cpuinfo | sort -u | wc -l)
+makejobs := $(nproc)
makethreads := $(shell dc -e "$(makejobs) 1 + p")
make_options := GCC49_AARCH64_PREFIX=$CROSS_COMPILE \
-j$(makethreads) -l$(makejobs)