下载SDK
登录NXP网站，选择MIMX8QX板子：
点击右边右边下载按钮：
点击下载SDK，下载压缩文件：SDK_2_9_0_MEK-MIMX8QX.zip
文档位置：SDK_2_9_0_MEK-MIMX8QX/Getting Started with MCUXpresso SDK for MEK-MIMX8QX.pdf，MCUXpresso SDK Release Notes for MEK-MIMX8QX.pdf
下载编译链
Arm GNU Toolchain | GNU Arm Embedded Toolchain Downloads – Arm Developer
选择最新版本工具链下载：
下载x86_64平台的工具链压缩包：
设置编译链
export PATH="/home/wangyb/sda3/SDK_2_9_0_MEK-MIMX8QX/toolchain/gcc-arm-none-eabi-10.3-2021.10/bin:$PATH"
export ARMGCC_DIR="/home/wangyb/sda3/SDK_2_9_0_MEK-MIMX8QX/toolchain/gcc-arm-none-eabi-10.3-2021.10"[wangyb@wangyb-VirtualBox:SDK_2_9_0_MEK-MIMX8QX]$ arm-none-eabi-gcc -v
Using built-in specs.
COLLECT_GCC=arm-none-eabi-gcc
COLLECT_LTO_WRAPPER=/home/wangyb/sda3/SDK_2_9_0_MEK-MIMX8QX/toolchain/gcc-arm-none-eabi-10.3-2021.10/bin/../lib/gcc/arm-none-eabi/10.3.1/lto-wrapper
Target: arm-none-eabi
Configured with: /mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/src/gcc/configure --target=arm-none-eabi --prefix=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/install-native --libexecdir=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/install-native/lib --infodir=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/install-native/share/doc/gcc-arm-none-eabi/info --mandir=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/install-native/share/doc/gcc-arm-none-eabi/man --htmldir=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/install-native/share/doc/gcc-arm-none-eabi/html --pdfdir=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/install-native/share/doc/gcc-arm-none-eabi/pdf --enable-languages=c,c++ --enable-plugins --disable-decimal-float --disable-libffi --disable-libgomp --disable-libmudflap --disable-libquadmath --disable-libssp --disable-libstdcxx-pch --disable-nls --disable-shared --disable-threads --disable-tls --with-gnu-as --with-gnu-ld --with-newlib --with-headers=yes --with-python-dir=share/gcc-arm-none-eabi --with-sysroot=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/install-native/arm-none-eabi --build=x86_64-linux-gnu --host=x86_64-linux-gnu --with-gmp=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/build-native/host-libs/usr --with-mpfr=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/build-native/host-libs/usr --with-mpc=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/build-native/host-libs/usr --with-isl=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/build-native/host-libs/usr --with-libelf=/mnt/workspace/workspace/GCC-10-pipeline/jenkins-GCC-10-pipeline-338_20211018_1634516203/build-native/host-libs/usr --with-host-libstdcxx='-static-libgcc -Wl,-Bstatic,-lstdc++,-Bdynamic -lm' --with-pkgversion='GNU Arm Embedded Toolchain 10.3-2021.10' --with-multilib-list=rmprofile,aprofile
Thread model: single
Supported LTO compression algorithms: zlib
gcc version 10.3.1 20210824 (release) (GNU Arm Embedded Toolchain 10.3-2021.10)
M4串口
=> tftp ${loadaddr} freertos_hello.bin;
Using ethernet@5b040000 device
TFTP from server 192.169.5.48; our IP address is 192.169.5.207
Filename 'freertos_hello.bin'.
Load address: 0x80280000
Loading: ##
677.7 KiB/s
done
Bytes transferred = 19432 (4be8 hex)
=> bootaux ${loadaddr};
## Starting auxiliary core at 0x80280000 ...
Power on aux core 0
Copy image from 0x80280000 to 0x34fe0000
Start M4
bootaux complete
为何使用malloc申请内存一次最大896/640字节，每次32字节最多800字节？这时为何？