Zynq exception handler

[Chris Johns]

On 29/09/2016 13:38, xuelin.tian at qkmtech.com wrote:
> I check the arm4-exception-default.S to see that, there are a few
> default handlers for ARM exceptions. But the default handlers are just
> to store the CPSR and return address. I may want to add some more to
> these. Because when I define some functions, error (multiple definition)
> comes up. Any hints about this? Thank you.

Have a look in my debug server code which I am developing. You can find 
it here 
https://ftp.rtems.org/pub/rtems/people/chrisj/dbserver/dbserver-1.0-20160915.tar.bz2

There are a couple of levels you can use to manage the error. The first 
is via the RTEMS interfaces. Look in init.c at the line:

#define CONFIGURE_INITIAL_EXTENSIONS { .fatal = fatal_extension }

Any of the error traps will end up here for you with a suitable frame to 
decode the issue. This is preferred.

If you need to get down to the hardware have a look in 
rtems-dbserver-arm.c and the rtems_dbserver_target_enable call. It 
updates the CP15 directly to have control pass directly to local 
exception handlers. This code also shows how to use naked handlers. You 
need to know how to handle the exception when at this level.

Chris