Hi Fangzhi, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: fb3b0673b7d5b477ed104949450cd511337ba3c6 commit: c022375ae0955b6d97ec438d658ab43a857a010f drm/amd/display: Add DP-HDMI FRL PCON Support in DC date: 6 weeks ago config: i386-allyesconfig (https://download.01.org/0day-ci/archive/20220114/202201141715.OhMqGKge-lk...) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout c022375ae0955b6d97ec438d658ab43a857a010f # save the config file to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc_link_dp.c:4343: warning: Function parameter or member 'max_supported_frl_bw_in_kbps' not described in 'intersect_frl_link_bw_support' drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc_link_dp.c:4343: warning: Function parameter or member 'hdmi_encoded_link_bw' not described in 'intersect_frl_link_bw_support' vim +4343 drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc_link_dp.c 4336 4337 /** 4338 * Return PCON's post FRL link training supported BW if its non-zero, otherwise return max_supported_frl_bw. 4339 */ 4340 static uint32_t intersect_frl_link_bw_support( 4341 const uint32_t max_supported_frl_bw_in_kbps, 4342 const union hdmi_encoded_link_bw hdmi_encoded_link_bw) 4344 uint32_t supported_bw_in_kbps = max_supported_frl_bw_in_kbps; 4345 4346 // HDMI_ENCODED_LINK_BW bits are only valid if HDMI Link Configuration bit is 1 (FRL mode) 4347 if (hdmi_encoded_link_bw.bits.FRL_MODE) { 4348 if (hdmi_encoded_link_bw.bits.BW_48Gbps) 4349 supported_bw_in_kbps = 48000000; 4350 else if (hdmi_encoded_link_bw.bits.BW_40Gbps) 4351 supported_bw_in_kbps = 40000000; 4352 else if (hdmi_encoded_link_bw.bits.BW_32Gbps) 4353 supported_bw_in_kbps = 32000000; 4354 else if (hdmi_encoded_link_bw.bits.BW_24Gbps) 4355 supported_bw_in_kbps = 24000000; 4356 else if (hdmi_encoded_link_bw.bits.BW_18Gbps) 4357 supported_bw_in_kbps = 18000000; 4358 else if (hdmi_encoded_link_bw.bits.BW_9Gbps) 4359 supported_bw_in_kbps = 9000000; 4360 } 4361 4362 return supported_bw_in_kbps; 4363 } 4364 #endif 4365 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org