查看Buildroot trouble shootings的源代码 Buildroot trouble shootings 0

1. toolchain-external-custom  Configuring
   Incorrect selection of kernel headers: expected 4.10.x, got 4.20.x
=> toolchain 配置错误, modify configd/defconfig
<source lang="java">
BR2_TOOLCHAIN_EXTERNAL=y
BR2_TOOLCHAIN_EXTERNAL_CUSTOM=y
BR2_TOOLCHAIN_EXTERNAL_PATH="/opt/gcc-linaro-7.5.0-2019.12-x86_64_aarch64-linux-gnu"
BR2_TOOLCHAIN_EXTERNAL_CUSTOM_PREFIX="aarch64-linux-gnu"
BR2_TOOLCHAIN_EXTERNAL_GCC_7=y
BR2_TOOLCHAIN_EXTERNAL_HEADERS_4_10=y
BR2_TOOLCHAIN_EXTERNAL_CUSTOM_GLIBC=y
BR2_TOOLCHAIN_EXTERNAL_CXX=y
</source>
To check kernel headers version of the toolchain:
cat /opt/gcc-linaro-7.5.0-2019.12-x86_64_aarch64-linux-gnu/aarch64-linux-gnu/libc/usr/include/linux/version.h
<source lang="java">
#define LINUX_VERSION_CODE 264707 (=0x040a03)
</source>
Match the required version 4.10

2. Download package too slow
Use download_cache, add
<source lang="java">
BR2_DL_DIR="/data/download_cache/buildroot"
</source>

3. add OpenCV4 into rootfs
vi package/opencv4/opencv4.mk
<source lang="java">
#with Qt5
ifeq ($(BR2_PACKAGE_OPENCV4_WITH_QT5),y)
OPENCV4_CONF_OPTS += -DWITH_QT=5
OPENCV4_DEPENDENCIES += qt5base
else
OPENCV4_CONF_OPTS += -DWITH_QT=OFF
endif

#add gapi
OPENCV4_CONF_OPTS += -DBUILD_opencv_gapi=ON 

#with OPENCL
OPENCV4_CONF_OPTS += \
    -DWITH_OPENCL=ON \
    -DWITH_OPENCL_SVM=OFF \
    -DWITH_OPENCLAMDBLAS=ON \
    -DWITH_OPENCLAMDFFT=ON

</source>
in .config [[文件:opencv4.jpg]]
<source lang="shell">
BR2_PACKAGE_OPENCV4=y
#
# OpenCV modules
#
BR2_PACKAGE_OPENCV4_LIB_CALIB3D=y
BR2_PACKAGE_OPENCV4_LIB_DNN=y
BR2_PACKAGE_OPENCV4_LIB_FEATURES2D=y
BR2_PACKAGE_OPENCV4_LIB_FLANN=y
BR2_PACKAGE_OPENCV4_LIB_HIGHGUI=y
BR2_PACKAGE_OPENCV4_WITH_QT5=y

#
# opengl support needs an OpenGL provider
#
BR2_PACKAGE_OPENCV4_LIB_IMGCODECS=y
BR2_PACKAGE_OPENCV4_LIB_IMGPROC=y
BR2_PACKAGE_OPENCV4_LIB_ML=y
BR2_PACKAGE_OPENCV4_LIB_OBJDETECT=y
BR2_PACKAGE_OPENCV4_LIB_PHOTO=y
BR2_PACKAGE_OPENCV4_LIB_SHAPE=y
BR2_PACKAGE_OPENCV4_LIB_STITCHING=y
# BR2_PACKAGE_OPENCV4_LIB_SUPERRES is not set
# BR2_PACKAGE_OPENCV4_LIB_TS is not set
BR2_PACKAGE_OPENCV4_LIB_VIDEOIO=y
BR2_PACKAGE_OPENCV4_LIB_VIDEO=y
BR2_PACKAGE_OPENCV4_LIB_VIDEOSTAB=y
#
# 3rd party support
#
BR2_PACKAGE_OPENCV4_WITH_FFMPEG=y
BR2_PACKAGE_OPENCV4_WITH_GSTREAMER1=y
BR2_PACKAGE_OPENCV4_JPEG2000_NONE=y
# BR2_PACKAGE_OPENCV4_JPEG2000_WITH_JASPER is not set
# BR2_PACKAGE_OPENCV4_JPEG2000_WITH_OPENJPEG is not set
# BR2_PACKAGE_OPENCV4_WITH_JPEG is not set
# BR2_PACKAGE_OPENCV4_WITH_PNG is not set
BR2_PACKAGE_OPENCV4_WITH_PROTOBUF=y
# BR2_PACKAGE_OPENCV4_WITH_TBB is not set
# BR2_PACKAGE_OPENCV4_WITH_TIFF is not set
BR2_PACKAGE_OPENCV4_WITH_V4L=y
# BR2_PACKAGE_OPENCV4_WITH_WEBP is not set

</source>