Embedded linux frequancy question

Embedded linux frequancy question:

1. 【linux脚本】在linux在执行脚本出现 bad interpreter: No such file or directory

一般来说，在windows用建立的sh文件在linux中运行时，因为window在每行后加入隐藏字符^M
所以当linux编译时 由于无法编译^M而导致bad interpreter错误

使用 vi -b 找出^M 然后删除。

 

2. 【Embeded linux】在target板上挂主机的NFS文件系统出现"error -13"
IP-Config: Got DHCP answer from 0.0.0.0, my address is 192.168.86.16
IP-Config: Complete:
      device=eth0, addr=192.168.86.16, mask=255.255.255.0, gw=192.168.86.1,
     host=192.168.86.16, domain=, nis-domain=(none),
     bootserver=0.0.0.0, rootserver=192.168.86.252, rootpath=
Looking up port of RPC 100003/2 on 192.168.86.252
Looking up port of RPC 100005/1 on 192.168.86.252
Root-NFS: Server returned error -13 while mounting /project/dengjj/gxv3140/rootfs/
VFS: Unable to mount root fs via NFS, trying floppy.

 

原因：在主机端没有开启NFS服务或已export the NFS server folder, 但没有用exportfs激活。

 

3, 【compile u-boot/linux】target CPU does not support interworking

 

start.S:0: warning: target CPU does not support interworking

 

【Reason】

which come from some ARM cross compilers and are caused by hard-coded
(with "--with-cpu=arm9" configuration option) ARM targets (which
support ARM Thumb instructions), while the ARM target selected from the command line (with "-march=armv4") doesn't support Thumb instructions.

 

This warning is issued by the compiler regardless of the real use of the Thumb instructions in code.

 

To fix this problem, we use options according to compiler version being used.