MPSOC之6——开发流程linux编译

0.顶层Makefile增加交叉编译器

顶层makefile:
ARCH ?= $(SUBARCH)
CROSS_COMPILE ?= $(CONFIG_CROSS_COMPILE:"%"=%)

改为:
ARCH ?= arm64
CROSS_COMPILE ?= aarch64-linux-gnu-

1.生成.config

***_defconfig文件一般的芯片都有,找到以后,用如下命令,其实就是拷贝到顶层目录,并命名为.config,里面包含一堆配置,make时读取。
***_defconfig文件在 arch/arm64/configs/目录下
[liuwanpeng@localhost linux]$ make xilinx_zynqmp_defconfig O=./output/
#
# configuration written to .config
#

单独输出到其他文件件有助于源码进行git管理,否则乱的文件。

2.make

[liuwanpeng@localhost linux]$ make LOADADDR=0x8000

默认生成Image,若想生成uImage,需要加上uImage后缀
[liuwanpeng@localhost linux]$ make LOADADDR=0x8000 uImage
make: *** 没有规则可以创建目标“uImage”。 停止。

2.1 uImage无法生成问题

mpsoc不像ZYNQ,把make uImage集成到makefile里了,可以单独执行mkimage指令。
mkimage是uboot编译后,生成的工具,拷贝到/usr/bin里

[liuwanpeng@localhost tools]$ mkimage
Error: Missing output filename
Usage: mkimage -l image
-l ==> list image header information
mkimage [-x] -A arch -O os -T type -C comp -a addr -e ep -n name -d data_file[:data_file...] image
-A ==> set architecture to 'arch'
-O ==> set operating system to 'os'
-T ==> set image type to 'type'
-C ==> set compression type 'comp'
-a ==> set load address to 'addr' (hex)
-e ==> set entry point to 'ep' (hex)
-n ==> set image name to 'name'
-d ==> use image data from 'datafile'
-x ==> set XIP (execute in place)
mkimage [-D dtc_options] [-f fit-image.its|-f auto|-F] [-b
[-b
]] [-i ] fit-image

file is used with -f auto, it may occur multiple times.
-D => set all options for device tree compiler
-f => input filename for FIT source
-i => input filename for ramdisk file
Signing / verified boot not supported (CONFIG_FIT_SIGNATURE undefined)
mkimage -V ==> print version information and exit
Use -T to see a list of available image types

在Image所在目录执行如下命令即可:
mkimage -n 'xlnx-linux' -A arm64 -O linux -T kernel -C none -a 0x00080000 -e 0x00080000 -d Image uImage

2.2 几种linux镜像格式

  • vmlinux 未压缩内核镜像文件,
  • zImage zImage是一般情况下默认的压缩内核映像文件,压缩vmlinux,加上一段解压启动代码得到,只能从0X0地址运行
  • uImage uImage是u-boot使用bootm命令引导的Linux压缩内核映像文件格式, 使用工具mkimage(uboot提供此工具)对普通的压缩内核映像文件(zImage)加工而得。可以由bootm命令从任意地址解压启动内核。由于bootloader一般要占用0x0地址,所以,uImage相比zImage的好处就是可以和bootloader共存。
  • 3. dts文件

    dts文件在arch/arm64/boot/dts中

    make dtbs

    可以生成dtb文件,整个目录都编译了
    make xxx.dtb

    不好用了,具体原因还未定位,估计是makefile体系的问题

    可以用dtc命令编译或反编译特定的dtb文件

    liuwanpeng@liuwanpeng-virtual-machine:~/work/linux/output/arch/arm64/boot/dts/xilinx$ dtc --help
    Usage: dtc [options]

    Options: -[qI:O:o:V:d:R:S:p:fb:i:H:sW:E:hv]
    -q, --quiet
    Quiet: -q suppress warnings, -qq errors, -qqq all
    -I, --in-format
    Input formats are:
    dts - device tree source text
    dtb - device tree blob
    fs - /proc/device-tree style directory
    -o, --out
    Output file
    -O, --out-format
    Output formats are:
    dts - device tree source text
    dtb - device tree blob
    asm - assembler source
    -V, --out-version
    Blob version to produce, defaults to 17 (for dtb and asm output)
    -d, --out-dependency
    Output dependency file
    -R, --reserve
    Make space for reserve map entries (for dtb and asm output)
    -S, --space
    Make the blob at least long (extra space)
    -p, --pad
    Add padding to the blob of long (extra space)
    -b, --boot-cpu
    Set the physical boot cpu
    -f, --force
    Try to produce output even if the input tree has errors
    -i, --include
    Add a path to search for include files
    -s, --sort
    Sort nodes and properties before outputting (useful for comparing trees)
    -H, --phandle
    Valid phandle formats are:
    legacy - "linux,phandle" properties only
    epapr - "phandle" properties only
    both - Both "linux,phandle" and "phandle" properties
    -W, --warning
    Enable/disable warnings (prefix with "no-")
    -E, --error
    Enable/disable errors (prefix with "no-")
    -h, --help
    Print this help and exit
    -v, --version
    Print version and exit

    例如:
    反汇编,由dtb生成dts,反之亦然
    dtc -I dtb -O dts -o zynqmp-zcu102.dts zynqmp-zcu102.dtb

    文章转载自: https://www.cnblogs.com/liuwanpeng/p/8074277.html

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