Hi Wenjing, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: d4a0ae62a277377de396850ed4b709b6bd9b7326 commit: d9eb8fea6862e63421f7b9c93e32bef348488c41 [1455/7915] drm/amd/display: Drop DCN for DP2.x logic config: arc-allyesconfig (https://download.01.org/0day-ci/archive/20220224/202202241919.bkJrrodR-lkp@xxxxxxxxx/config) compiler: arceb-elf-gcc (GCC) 11.2.0 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=d9eb8fea6862e63421f7b9c93e32bef348488c41 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 d9eb8fea6862e63421f7b9c93e32bef348488c41 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=arc SHELL=/bin/bash drivers/gpu/drm/amd/amdgpu/ drivers/gpu/drm/amd/display/amdgpu_dm/ drivers/gpu/drm/amd/display/dc/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_helpers.c:805:6: warning: no previous prototype for 'dm_helpers_enable_periodic_detection' [-Wmissing-prototypes] 805 | void dm_helpers_enable_periodic_detection(struct dc_context *ctx, bool enable) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ vim +/dm_helpers_enable_periodic_detection +805 drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_helpers.c ac02dc34258569 Eric Yang 2021-08-25 804 ac02dc34258569 Eric Yang 2021-08-25 @805 void dm_helpers_enable_periodic_detection(struct dc_context *ctx, bool enable) :::::: The code at line 805 was first introduced by commit :::::: ac02dc34258569b793b78483154ca336f103946f drm/amd/display: Add periodic detection when zstate is enabled :::::: TO: Eric Yang <Eric.Yang2@xxxxxxx> :::::: CC: Alex Deucher <alexander.deucher@xxxxxxx> --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
