设备树
dts:device tree source
dtc
dtc:device tree compiler
# dtc -help
Usage:
dtc [options] <input file>
Options:
-h
This help text
-q
Quiet: -q suppress warnings, -qq errors, -qqq all
-I <input format>
Input formats are:
dts - device tree source text
dtb - device tree blob
fs - /proc/device-tree style directory
-o <output file>
-O <output format>
Output formats are:
dts - device tree source text
dtb - device tree blob
asm - assembler source
-V <output version>
Blob version to produce, defaults to 17 (relevant for dtb
and asm output only)
-d <output dependency file>
-R <number>
Make space for <number> reserve map entries (relevant for
dtb and asm output only)
-S <bytes>
Make the blob at least <bytes> long (extra space)
-p <bytes>
Add padding to the blob of <bytes> long (extra space)
-b <number>
Set the physical boot cpu
-f
Force - try to produce output even if the input tree has errors
-s
Sort nodes and properties before outputting (only useful for
comparing trees)
-v
Print DTC version and exit
-H <phandle format>
phandle formats are:
legacy - "linux,phandle" properties only
epapr - "phandle" properties only
both - Both "linux,phandle" and "phandle" properties
举例
dtb:device tree blob
# dtc -I dts -O dtb -o dest.dtb src.dts
dtc将dts编译成二进制格式dtb
bootloader在引导kernel的过程中,会先读取该dtb到内存
dtb地址设置
# fdt addr xxx //内存地址