Hi Sui, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on drm-misc/drm-misc-next] [also build test WARNING on linus/master v6.3-rc4 next-20230328] [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#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Sui-Jingfeng/MAINTAINERS-add-maintainers-for-DRM-LOONGSON-driver/20230320-180408 base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next patch link: https://lore.kernel.org/r/20230320100131.1277034-3-15330273260%40189.cn patch subject: [PATCH v8 2/2] drm: add kms driver for loongson display controller config: i386-allyesconfig (https://download.01.org/0day-ci/archive/20230328/202303281754.jWI20j2C-lkp@xxxxxxxxx/config) compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1) 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-lab-lkp/linux/commit/80b4115f44993f4ebf47b1cb9e8f02953575b977 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Sui-Jingfeng/MAINTAINERS-add-maintainers-for-DRM-LOONGSON-driver/20230320-180408 git checkout 80b4115f44993f4ebf47b1cb9e8f02953575b977 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/accel/ drivers/gpu/drm/loongson/ drivers/iio/light/ drivers/media/pci/intel/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Link: https://lore.kernel.org/oe-kbuild-all/202303281754.jWI20j2C-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): >> drivers/gpu/drm/loongson/lsdc_drv.c:232:11: warning: variable 'gpu' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] else if (descp->chip == CHIP_LS7A2000) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/loongson/lsdc_drv.c:235:7: note: uninitialized use occurs here if (!gpu) { ^~~ drivers/gpu/drm/loongson/lsdc_drv.c:232:7: note: remove the 'if' if its condition is always true else if (descp->chip == CHIP_LS7A2000) ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/loongson/lsdc_drv.c:217:21: note: initialize the variable 'gpu' to silence this warning struct pci_dev *gpu; ^ = NULL 1 warning generated. -- >> drivers/gpu/drm/loongson/lsdc_pll.c:188:14: warning: variable 'diff' is used uninitialized whenever 'if' condition is false [-Wsometimes-uninitialized] else if (clock_khz < computed) ^~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/loongson/lsdc_pll.c:191:9: note: uninitialized use occurs here if (diff < min) { ^~~~ drivers/gpu/drm/loongson/lsdc_pll.c:188:10: note: remove the 'if' if its condition is always true else if (clock_khz < computed) ^~~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/loongson/lsdc_pll.c:177:22: note: initialize the variable 'diff' to silence this warning unsigned int diff; ^ = 0 1 warning generated. vim +232 drivers/gpu/drm/loongson/lsdc_drv.c 212 213 static int lsdc_get_dedicated_vram(struct lsdc_device *ldev, 214 const struct lsdc_desc *descp) 215 { 216 struct drm_device *ddev = &ldev->base; 217 struct pci_dev *gpu; 218 resource_size_t base, size; 219 220 /* 221 * The GPU and display controller in LS7A1000/LS7A2000 are separated 222 * PCIE devices, they are two devices not one. The DC does not has a 223 * dedicate VRAM bar, because the BIOS engineer choose to assign the 224 * VRAM to the GPU device. Sadly, after years application, this form 225 * as a convention for loongson integrated graphics. Bar 2 of the GPU 226 * device contain the base address and size of the VRAM, both the GPU 227 * and the DC can access the on-board VRAM as long as the DMA address 228 * emitted fall in [base, base + size). 229 */ 230 if (descp->chip == CHIP_LS7A1000) 231 gpu = pci_get_device(PCI_VENDOR_ID_LOONGSON, 0x7A15, NULL); > 232 else if (descp->chip == CHIP_LS7A2000) 233 gpu = pci_get_device(PCI_VENDOR_ID_LOONGSON, 0x7A25, NULL); 234 235 if (!gpu) { 236 drm_warn(ddev, "No GPU device found\n"); 237 return -ENODEV; 238 } 239 240 base = pci_resource_start(gpu, 2); 241 size = pci_resource_len(gpu, 2); 242 243 ldev->vram_base = base; 244 ldev->vram_size = size; 245 246 drm_info(ddev, "dedicated vram start: 0x%llx, size: %uMB\n", 247 (u64)base, (u32)(size >> 20)); 248 249 return 0; 250 } 251 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
