📄 221.htm
字号:
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>CTerm非常精华下载</title>
</head>
<body bgcolor="#FFFFFF">
<table border="0" width="100%" cellspacing="0" cellpadding="0" height="577">
<tr><td width="32%" rowspan="3" height="123"><img src="DDl_back.jpg" width="300" height="129" alt="DDl_back.jpg"></td><td width="30%" background="DDl_back2.jpg" height="35"><p align="center"><a href="http://202.112.58.200"><font face="黑体"><big><big>Tsinghua</big></big></font></a></td></tr>
<tr>
<td width="68%" background="DDl_back2.jpg" height="44"><big><big><font face="黑体"><p align="center"> 嵌入式系统 (BM: turbolinux jacobw) </font></big></big></td></tr>
<tr>
<td width="68%" height="44" bgcolor="#000000"><font face="黑体"><big><big><p align="center"></big></big><a href="http://cterm.163.net"><img src="banner.gif" width="400" height="60" alt="banner.gif"border="0"></a></font></td>
</tr>
<tr><td width="100%" colspan="2" height="100" align="center" valign="top"><br><p align="center">[<a href="嵌入式系统.htm">回到开始</a>][<a href="198.htm">上一层</a>][<a href="222.htm">下一篇</a>]
<hr><p align="left"><small>发信人: plato (纯真年代), 信区: Embedded <br>
标 题: linux for ppc chapter 20 <br>
发信站: BBS 水木清华站 (Wed May 30 23:24:22 2001) <br>
<br>
Next Previous Contents <br>
---------------------------------------------------------------------------- <br>
---- <br>
20. Common Mistakes and Problems <br>
Many new developers are likely to encounter at least half of the following c <br>
ommon problems, which are raised often on the mailing list. Keep this sectio <br>
n in mind to refer to when you spot the symptom. <br>
20.1 Changing KERNELBASE/KERNELLOAD <br>
You don't ever want to change KERNELLOAD or KERNELBASE, otherwise the virtua <br>
l memory and MMU code will all break. Search for KERNELBASE. <br>
20.2 Leaving the Watchdog enabled <br>
The watchdog is enabled by default, and needs to be disabled at reset for an <br>
ything including BDM to work. <br>
20.3 Mixing code compiled for software and hardware floating point <br>
The usual non-obvious cause of this is combining executables compiled with - <br>
fsoft-float and shared libraries compiled with -fhard-float, or vice-versa. <br>
See floating point. <br>
20.4 Using an unmodified glibc <br>
In particular, remember to remove (or correct the cache line assumptions in) <br>
sysdeps/powerpc/memset.S before building glibc-2.1.3. <br>
20.5 "Kernel Mode Software FPU Emulation" panic <br>
This has little to do with floating point. Nearly all instructions the proce <br>
ssor can't decode are vectored to this function. It assumes the primary reas <br>
on you are here is to emulate floating point instructions. If the function c <br>
an't decode the instruction as a floating point operation, it is really some <br>
thing the processor can't execute, so the panic message spews forth. <br>
This can be either a software or hardware bug. If it is a software bug, just <br>
unravel the stack backtrace and debug it. It could be a trashed stack frame <br>
, resulting in a bad function return address, or some indirect function call <br>
that was not properly computed. <br>
It could also happen because of a hardware bug while fetching instructions f <br>
rom memory. Verify the NIP instruction that it tried to decode is what is re <br>
ally supposed to be at that location in memory. This is a typical failure wh <br>
en the UPM is not programmed correctly. On a custom board in particular, ver <br>
ify all memory cycles an a logic analyser. Disable the cache and try again, <br>
you will probably get a different result. <br>
20.6 NFS gives "neighbour table overflow" <br>
This message is the result of some changes to the IP stack software in Linux <br>
version 2.2.x +. This simply means that you are unable to connect to your N <br>
FS server. It may be related to the driver, but it may also be related to ot <br>
her issues, such as NFS server not running or incorrectly installed, no phys <br>
ical connectivity to NFS server, etc. Check the configuration of your NFS se <br>
rver and IP network before diving into the driver. <br>
20.7 "Kernel panic: No init found..." on startup <br>
Either you don't have an init program of some type (even /bin/sh) in your ro <br>
ot filesystem, or you don't have enough shared libraries and the program can <br>
't be loaded properly, although you often get messages about not able to loa <br>
d some .so. Usually the problem is missing or misplaced shared libraries. <br>
To start up /bin/sh, which is a good thing to try initially, you need the en <br>
tire set of glibc shared libraries and libtermcap.so. If you're using the Mo <br>
ntaVista CDK, you get these from the glibc and termcap RPMs, and remember yo <br>
u also need that funky sym link: /opt/hardhat/devkit/ppc/8xx/powerpc-hardhat <br>
-linux -> / in the target filesystem. <br>
You can find out which shared libraries any binary requires using ldd(1), bu <br>
t it only runs on the target and isn't much use if you're cross developing a <br>
nd can't even start a shell yet. A shell script which runs on the host and d <br>
oes much the same thing is available at: http://lists.linuxppc.org/listarcs/ <br>
linuxppc-embedded/200102/msg00011.html. <br>
---------------------------------------------------------------------------- <br>
---- <br>
Next Previous Contents <br>
<br>
-- <br>
<br>
※ 来源:·BBS 水木清华站 smth.org·[FROM: 166.111.161.8] <br>
</small><hr>
<p align="center">[<a href="嵌入式系统.htm">回到开始</a>][<a href="198.htm">上一层</a>][<a href="222.htm">下一篇</a>]
<p align="center"><a href="http://cterm.163.net">欢迎访问Cterm主页</a></p>
</table>
</body>
</html>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -