How to export kernel functions which written in assembly?

I am working with a PowerPC processor and have to use dcache functions in my kernel module, like: "clean_dcache_range()", implemented in $KERNEL_SOURCE/arch/powerpc/kernel/misc_32.S. this assembly file is compiled during kernel compilation (version 4.1.8) and misc_32.o object file exists in kernel build directory.
However, i can't use this functions in my kernel module and the error "implicit declaration of function" appears when i compile the module using gcc.
Also, the Module.symvers file does not contain these functions. Note that, the mentioned functions are declared as _GLOBAL.
So, what is the problem and how can i solve it?