tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: be978f8feb1d4678b941a3ccf181eea1039110e2 commit: a28c9475256ffcbc9fb715b316fcb5e95e4df9be [7820/7824] sh: clkfwk: remove r8/r16/r32 config: sh-se7721_defconfig (attached as .config) compiler: sh4-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 git checkout a28c9475256ffcbc9fb715b316fcb5e95e4df9be # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sh If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): drivers/sh/clk/cpg.c: In function 'sh_clk_mstp_enable': 49 | read = ioread8; | ^ drivers/sh/clk/cpg.c:51:9: error: assignment to 'unsigned int (*)(void *)' from incompatible pointer type 'unsigned int (*)(const void *)' [-Werror=incompatible-pointer-types] 51 | read = ioread16; | ^ drivers/sh/clk/cpg.c:53:9: error: assignment to 'unsigned int (*)(void *)' from incompatible pointer type 'unsigned int (*)(const void *)' [-Werror=incompatible-pointer-types] 53 | read = ioread32; | ^ cc1: some warnings being treated as errors vim +49 drivers/sh/clk/cpg.c 38 39 static int sh_clk_mstp_enable(struct clk *clk) 40 { 41 sh_clk_write(sh_clk_read(clk) & ~(1 << clk->enable_bit), clk); 42 if (clk->status_reg) { 43 unsigned int (*read)(void __iomem *addr); 44 int i; 45 void __iomem *mapped_status = (phys_addr_t)clk->status_reg - 46 (phys_addr_t)clk->enable_reg + clk->mapped_reg; 47 48 if (clk->flags & CLK_ENABLE_REG_8BIT) 50 else if (clk->flags & CLK_ENABLE_REG_16BIT) 51 read = ioread16; 52 else 53 read = ioread32; 54 55 for (i = 1000; 56 (read(mapped_status) & (1 << clk->enable_bit)) && i; 57 i--) 58 cpu_relax(); 59 if (!i) { 60 pr_err("cpg: failed to enable %p[%d]\n", 61 clk->enable_reg, clk->enable_bit); 62 return -ETIMEDOUT; 63 } 64 } 65 return 0; 66 } 67 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org