tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   59fa6a163ffabc1bf25c5e0e33899e268a96d3cc
commit: a579fcfa8e49cc77ad59211bb18bc5004133e6a0 [4548/6048] c6x: remove architecture
config: c6x-randconfig-r004-20210202 (attached as .config)
compiler: c6x-elf-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=a579fcfa8e49cc77ad59211bb18bc5004133e6a0
        git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
        git fetch --no-tags linux-next master
        git checkout a579fcfa8e49cc77ad59211bb18bc5004133e6a0
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=c6x 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All errors (new ones prefixed by >>):

   Makefile:681: arch/c6x/Makefile: No such file or directory
   make[1]: *** No rule to make target 'arch/c6x/Makefile'.
   Makefile:595: arch/c6x/Makefile: No such file or directory
   make[2]: *** No rule to make target 'arch/c6x/Makefile'.
   make[2]: Failed to remake makefile 'arch/c6x/Makefile'.
   arch/Kconfig:10: can't open file "arch/c6x/Kconfig"
   make[3]: *** [scripts/kconfig/Makefile:71: syncconfig] Error 1
   make[2]: *** [Makefile:602: syncconfig] Error 2
   make[1]: *** [Makefile:710: include/config/auto.conf.cmd] Error 2
   make[1]: Failed to remake makefile 'include/config/auto.conf.cmd'.
   make[1]: Failed to remake makefile 'arch/c6x/Makefile'.
   make[1]: Failed to remake makefile 'include/config/auto.conf'.

quoted

make[1]: *** No rule to make target 'modules_prepare'.

   make: *** [Makefile:185: __sub-make] Error 2
   make: Target 'modules_prepare' not remade because of errors.

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org