[U-Boot] Difference between _defconfig and _config make switches

[Ahmad Ijaz]

Hi Sir,

I am trying to understand u-boot source code. As a starting point, I
compiled u-boot for beaglebone black and successfully executed it on
beaglebone hardware.
My question is related to compilation step.

The u-boot can be compiled with the following switches on *make.*

*1. am335x_beaglebone_defconfig*
*2. am335x_beaglebone_config*
*3. am335x_evm_defconfig*
*4. am335x_evm_config*

All compiles fine. but whats the difference b/w " **_defconfig" AND "
*_config". *Interestingly there are no script in the /config directory
ending with *_config *(all ends with _defconfig). I tried to read the
Makefile to find out if these switches may be pointing to a file but
couldn't get it.

Please give me a direction in this regard. Are they switches or name of
configuration files?
waiting for your kind reply.

Kind regards,
Ijaz