Hi Zhenneng, 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 v5.19 next-20220811] [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/Zhenneng-Li/drm-amdgpu-use-native-mode-for-dp-aux-transfer/20220811-193443 base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next config: i386-allyesconfig (https://download.01.org/0day-ci/archive/20220812/202208120737.JG7NkugC-lkp@xxxxxxxxx/config) compiler: gcc-11 (Debian 11.3.0-3) 11.3.0 reproduce (this is a W=1 build): # https://github.com/intel-lab-lkp/linux/commit/1098c6fecb4292d634dbdccff9e720400dc7138d git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Zhenneng-Li/drm-amdgpu-use-native-mode-for-dp-aux-transfer/20220811-193443 git checkout 1098c6fecb4292d634dbdccff9e720400dc7138d # save the config file mkdir build_dir && cp config build_dir/.config make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/gpu/drm/amd/amdgpu/ If you fix the issue, kindly add following tag where applicable Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> drivers/gpu/drm/amd/amdgpu/amdgpu_dp_auxch.c:73:10: warning: no previous prototype for 'venus_mm_rreg_slow' [-Wmissing-prototypes] 73 | uint32_t venus_mm_rreg_slow(struct amdgpu_device *adev, uint32_t reg) | ^~~~~~~~~~~~~~~~~~ >> drivers/gpu/drm/amd/amdgpu/amdgpu_dp_auxch.c:84:6: warning: no previous prototype for 'venus_mm_wreg_slow' [-Wmissing-prototypes] 84 | void venus_mm_wreg_slow(struct amdgpu_device *adev, uint32_t reg, uint32_t v) | ^~~~~~~~~~~~~~~~~~ vim +/venus_mm_rreg_slow +73 drivers/gpu/drm/amd/amdgpu/amdgpu_dp_auxch.c 69 70 #define R100_MM_INDEX 0x0000 71 #define R100_MM_DATA 0x0004 72 #define AMDGPU_MIN_MMIO_SIZE 0x10000 > 73 uint32_t venus_mm_rreg_slow(struct amdgpu_device *adev, uint32_t reg) 74 { 75 unsigned long flags; 76 uint32_t ret; 77 78 spin_lock_irqsave(&adev->mmio_idx_lock, flags); 79 writel(reg, ((void __iomem *)adev->rmmio) + R100_MM_INDEX); 80 ret = readl(((void __iomem *)adev->rmmio) + R100_MM_DATA); 81 spin_unlock_irqrestore(&adev->mmio_idx_lock, flags); 82 return ret; 83 } > 84 void venus_mm_wreg_slow(struct amdgpu_device *adev, uint32_t reg, uint32_t v) 85 { 86 unsigned long flags; 87 88 spin_lock_irqsave(&adev->mmio_idx_lock, flags); 89 writel(reg, ((void __iomem *)adev->rmmio) + R100_MM_INDEX); 90 writel(v, ((void __iomem *)adev->rmmio) + R100_MM_DATA); 91 spin_unlock_irqrestore(&adev->mmio_idx_lock, flags); 92 } 93 static inline uint32_t venus_mm_rreg(struct amdgpu_device *adev, uint32_t reg, 94 bool always_indirect) 95 { 96 /* The mmio size is 64kb at minimum. Allows the if to be optimized out. */ 97 if ((reg < adev->rmmio_size || reg < AMDGPU_MIN_MMIO_SIZE) && !always_indirect) 98 return readl(((void __iomem *)adev->rmmio) + reg); 99 else 100 return venus_mm_rreg_slow(adev, reg); 101 } 102 static inline void venus_mm_wreg(struct amdgpu_device *adev, uint32_t reg, uint32_t v, 103 bool always_indirect) 104 { 105 if ((reg < adev->rmmio_size || reg < AMDGPU_MIN_MMIO_SIZE) && !always_indirect) 106 writel(v, ((void __iomem *)adev->rmmio) + reg); 107 else 108 venus_mm_wreg_slow(adev, reg, v); 109 } 110 -- 0-DAY CI Kernel Test Service https://01.org/lkp