快乐虾
http://blog.csdn.net/lights_joy/
lights@hb165.com
本文适用于
ADI bf561 DSP
优视BF561EVB开发板
uclinux-2008r1-rc8 (移植到vdsp5)
Visual DSP++ 5.0
默认情况下,2008r1版本的内核使用了initramfs做为rootfs,而为了将rootfs与内核放在一起,在链接文件ldf中做了一下处理:
INPUT_SECTION_ALIGN(4)
___initramfs_start = (. + 3) / 4 * 4;
INPUT_SECTIONS($LIBRARIES_UCLINUX(.init.ramfs))
___initramfs_end = .;
再看一下.init.ramfs这个段的数据来源:
在usr目录下有一个叫initramfs_data.S的文件,就两句话:
.section .init.ramfs,"a"
.incbin "/usr/initramfs_data.cpio.gz"
其意思无非就是说将initramfs_data.cpio.gz这个文件的内容读出来放在.init.ramfs这个段中。
但是在VDSP下使用时出现一个可恶的问题,老是提示无法找到规则编译
initramfs_data.cpio.gz。况且在VDSP下也不支持.incbin,而是支持.inc/binary,因此直接将这两行代码复制到arch/blackfin/fixed_code.s中,并修改为:
.section .init.ramfs,"a"
.inc/binary "../../usr/initramfs_data.cpio.gz"
这样,就可以将initramfs_data.cpio.gz文件中的内容放到.init.ramfs段中了。
参考VDSP文档:
INC/BINARY, Include Contents of a File
The
.INC/BINARY directive includes the content of file at the current location. You can control the search paths used via the -i command-line switch (click here).
Syntax:
.INC/BINARY [ symbol = ] "filename" [,skip [,count]] ;
.INC/BINARY [ symbol[] = ] "filename" [,skip [,count]] ;
where
symbol – the name of a symbol to associate with the data being included from the file
filename – the name of the file to include. The argument is enclosed in double quotes.
The
skip argument skips a number of bytes from the start of the file.
The
count argument indicates the maximum number of bytes to read.
Example:
.SECTION data1;
.VAR jim;
.INC/BINARY sym[] = "bert",10,6;
.VAR fred;
.INC/BINARY Image1[] = "photos/Picture1.jpg";