tree: https://git.kernel.org/pub/scm/linux/kernel/git/kbingham/rcar.git vsp1/v3u head: 15890c07a0b56cea8221557f4c28a2052c1b3d14 commit: 7708982fa60fe0d474f68d42d0354e1973df954d [17/69] drm: rcar-du: Add R-Car DSI driver config: openrisc-randconfig-r001-20210519 (attached as .config) compiler: or1k-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://git.kernel.org/pub/scm/linux/kernel/git/kbingham/rcar.git/commit/... git remote add rcar https://git.kernel.org/pub/scm/linux/kernel/git/kbingham/rcar.git git fetch --no-tags rcar vsp1/v3u git checkout 7708982fa60fe0d474f68d42d0354e1973df954d # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=openrisc 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/rcar-du/rcar_mipi_dsi.c:95:2: warning: this decimal constant is unsigned only in ISO C90 95 | {2100000000, 0x41}, {2150000000, 0x42}, {2200000000, 0x43}, | ^ drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c:95:2: warning: this decimal constant is unsigned only in ISO C90 drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c:96:2: warning: this decimal constant is unsigned only in ISO C90 96 | {2250000000, 0x44}, {2300000000, 0x45}, {2350000000, 0x46}, | ^ drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c:96:2: warning: this decimal constant is unsigned only in ISO C90 drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c:96:2: warning: this decimal constant is unsigned only in ISO C90 drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c:97:2: warning: this decimal constant is unsigned only in ISO C90 97 | {2400000000, 0x47}, {2450000000, 0x48}, {2500000000, 0x49}, | ^ drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c:97:2: warning: this decimal constant is unsigned only in ISO C90 drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c:97:2: warning: this decimal constant is unsigned only in ISO C90 613 | int rcar_mipi_dsi_clk_enable(struct drm_bridge *bridge) | ^~~~~~~~~~~~~~~~~~~~~~~~ 636 | void rcar_mipi_dsi_clk_disable(struct drm_bridge *bridge) | ^~~~~~~~~~~~~~~~~~~~~~~~~ vim +/rcar_mipi_dsi_clk_enable +613 drivers/gpu/drm/rcar-du/rcar_mipi_dsi.c 608 609 /* ----------------------------------------------------------------------------- 610 * Clock Setting 611 */ 612 614 { 615 struct rcar_mipi_dsi *mipi_dsi = bridge_to_rcar_mipi_dsi(bridge); 616 int ret; 617 618 reset_control_deassert(mipi_dsi->rstc); 619 620 ret = clk_prepare_enable(mipi_dsi->clocks.mod); 621 if (ret < 0) 622 return ret; 623 624 ret = clk_prepare_enable(mipi_dsi->clocks.dsi); 625 if (ret < 0) 626 return ret; 627 628 ret = rcar_mipi_dsi_startup(mipi_dsi); 629 if (ret < 0) 630 return ret; 631 632 return 0; 633 } 634 EXPORT_SYMBOL_GPL(rcar_mipi_dsi_clk_enable); 635 637 { 638 struct rcar_mipi_dsi *mipi_dsi = bridge_to_rcar_mipi_dsi(bridge); 639 640 rcar_mipi_dsi_shutdown(mipi_dsi); 641 642 /* Disable DSI clock and reset HW */ 643 clk_disable_unprepare(mipi_dsi->clocks.dsi); 644 645 clk_disable_unprepare(mipi_dsi->clocks.mod); 646 647 reset_control_assert(mipi_dsi->rstc); 648 } 649 EXPORT_SYMBOL_GPL(rcar_mipi_dsi_clk_disable); 650 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org