tree: https://github.com/intel/linux-intel-lts.git 5.4/yocto head: eeb611e5394c56d45c5cc8f7dc484c9f19e93143 commit: 00dead639798facd88b7e8c26614a49ec2e15cd9 [82/1142] drm/kmb: Changes for LCD to Mipi config: arm64-allyesconfig (attached as .config) compiler: aarch64-linux-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://github.com/intel/linux-intel-lts/commit/00dead639798facd88b7e8c26... git remote add intel-linux-intel-lts https://github.com/intel/linux-intel-lts.git git fetch --no-tags intel-linux-intel-lts 5.4/yocto git checkout 00dead639798facd88b7e8c26614a49ec2e15cd9 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm64 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/kmb/kmb_dsi.c:427:5: warning: no previous prototype for 'mipi_get_datatype_params' [-Wmissing-prototypes] 427 | u32 mipi_get_datatype_params(u32 data_type, u32 data_mode, | ^~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/kmb/kmb_dsi.c:930:5: warning: no previous prototype for 'dphy_read_testcode' [-Wmissing-prototypes] 930 | int dphy_read_testcode(struct kmb_drm_private *dev_p, int dphy_sel, | ^~~~~~~~~~~~~~~~~~ drivers/gpu/drm/kmb/kmb_dsi.c: In function 'wait_init_done': drivers/gpu/drm/kmb/kmb_dsi.c:1563:13: warning: variable 'val' set but not used [-Wunused-but-set-variable] 1563 | int i = 0, val; | ^~~ drivers/gpu/drm/kmb/kmb_dsi.c: At top level: 1698 | void connect_lcd_to_mipi(struct kmb_drm_private *dev_p) | ^~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/kmb/kmb_dsi.c:1721:5: warning: no previous prototype for 'kmb_kernel_read' [-Wmissing-prototypes] 1721 | int kmb_kernel_read(struct file *file, loff_t offset, | ^~~~~~~~~~~~~~~ drivers/gpu/drm/kmb/kmb_dsi.c: In function 'kmb_dsi_init': drivers/gpu/drm/kmb/kmb_dsi.c:1771:6: warning: variable 'ret' set but not used [-Wunused-but-set-variable] 1771 | int ret = 0; | ^~~ vim +/connect_lcd_to_mipi +1698 drivers/gpu/drm/kmb/kmb_dsi.c 1697 1699 { 1700 #ifdef LCD_TEST 1701 /*connect lcd to mipi */ 1702 /*DISABLE MIPI->CIF CONNECTION*/ 1703 kmb_write_msscam(dev_p, MSS_MIPI_CIF_CFG, 0); 1704 /*ENABLE LCD->MIPI CONNECTION */ 1705 kmb_write_msscam(dev_p, MSS_LCD_MIPI_CFG, 1); 1706 /*DISABLE LCD->CIF LOOPBACK */ 1707 kmb_write_msscam(dev_p, MSS_LOOPBACK_CFG, 0); 1708 #endif 1709 } 1710 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org