Specifications

When I try to compile my LInux kernel after applying the RTAI patch, I get a strange "asm-specifier
for variable `__sc_3' conflicts with asm clobber list" error message. What does that mean?
Answer:
You are using an old version of the Linux kernel / RTAI patch in combination with a more recent
version of the cross compiler. Please use a recent kernel tree (and the corresponding RTAI patch), or
apply the attached patch to fix this problem.
See: http://www.denx.de/wiki/pub/DULG/ConflictsWithAsmClobberList/patch
14.6. BDI2000
14.6.1. Where can I find BDI2000 Configuration
Files?
The configuration files provided by Abatron can be found here: ftp://94.230.212.16/bdigdb/config/
A collection of configuration files for the BDI2000 BDM/JTAG debugger by Abatron can be found at
ftp://ftp.denx.de/pub/BDI2000/
A list of FAQ (with answers) can be found at http://www.ultsol.com/faqs.htm
A list of supported flash chips (and the needed matching entries for the config file) can be found at
http://www.abatron.ch/fileadmin/user_upload/products/pdf/flashsupp.pdf
14.6.2. How to Debug Linux Exceptions
Question:
I am trying to single step into a Linux exception handler. This does not seem to work. Setting a
breakpoint does not work either.
Answer:
The problem is bit complex on a MPC8xx target. Debug mode entry is like an exception and therefore
only safe at locations in the code where an exception does not lead to an unrecoverable state. Another
exception can only be accepted if SRR0 and SRR1 are saved. The MSR[RI] should indicate if
currently an exception is safe. MSR[RI] is cleared automatically at exception entry.
The MPC8xx hardware breakpoints do only trigger if MSR[RI] is set in order to prevent
non-recoverable state.
The problem is that the Linux exception handler does not take all this into account. First priority has
speed, therefore neither SRR0 nor SRR1 are saved immediately. Only after EXCEPTION_PROLOG
this registers are saved. Also Linux does not handle the MSR[RI] bit.
Hint: Use STEPMODE HWBP when debugging Linux. This allows the TLB Miss Exception
handler to update the TLB while you are single stepping.
14.6.2. How to Debug Linux Exceptions 201