Hi Sascha,

I love your patch! Perhaps something to improve:

[auto build test WARNING on rockchip/for-next]
[also build test WARNING on drm/drm-next v5.16-rc2 next-20211125]
[cannot apply to arm64/for-next/core]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Sascha-Hauer/drm-rockchip-RK356x-VOP2-support/20211117-223601
base:   https://git.kernel.org/pub/scm/linux/kernel/git/mmind/linux-rockchip.git for-next
config: mips-allmodconfig (https://download.01.org/0day-ci/archive/20211126/202111261442.VG18rKq6-lkp@intel.com/config)
compiler: mips-linux-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://github.com/0day-ci/linux/commit/f8c11ce8b4d254bb4824a87adbf9ed187a3c1178
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Sascha-Hauer/drm-rockchip-RK356x-VOP2-support/20211117-223601
        git checkout f8c11ce8b4d254bb4824a87adbf9ed187a3c1178
        # save the config file to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=mips 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All warnings (new ones prefixed by >>):

   drivers/gpu/drm/rockchip/rockchip_drm_vop2.c: In function 'vop2_setup_dly_for_window':

quoted

drivers/gpu/drm/rockchip/rockchip_drm_vop2.c:2943:27: warning: variable 'plane' set but not used [-Wunused-but-set-variable]

    2943 |         struct drm_plane *plane;
         |                           ^~~~~


vim +/plane +2943 drivers/gpu/drm/rockchip/rockchip_drm_vop2.c

  2937	
  2938	static void vop2_setup_dly_for_window(struct vop2_video_port *vp, const struct vop2_zpos *vop2_zpos,
  2939					      int nr_layers)
  2940	{
  2941		struct vop2 *vop2 = vp->vop2;
  2942		const struct vop2_zpos *zpos;

2943		struct drm_plane *plane;

  2944		struct vop2_win *win;
  2945		uint32_t dly;
  2946		int i = 0;
  2947	
  2948		for (i = 0; i < nr_layers; i++) {
  2949			zpos = &vop2_zpos[i];
  2950			win = zpos->win;
  2951			plane = &win->base;
  2952			dly = win->data->dly[VOP2_DLY_MODE_DEFAULT];
  2953	
  2954			if (vop2_cluster_window(win))
  2955				dly |= dly << 8;
  2956	
  2957			vop2_write(vop2, &vop2->data->ctrl->win_dly[win->data->phys_id], dly);
  2958		}
  2959	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org