Question about backdoor map

[walkeranderson]

 

I'm trying to set up user-defined backdoor access to a memory.  I created a derived uvm_reg_backdoor object and configured the memory with it.  When I do a backdoor write to this memory, I get this warning:

 

UVM_WARNING @ 0 ns: reporter [RegModel] Memory 'mem.Memory' is not contained within map 'Backdoor' (called from get_access())

 

Digging into the UVM source code, I can see some code using the map returned by the static uvm_reg_map::backdoor() which returns its local m_backdoor (after creating a map first if it happens to be null).

 

I tried using uvm_reg_map::backdoor() to get a reference to this map and then using it to add my memory to the map but this error:

 

        UVM_ERROR @ 0 ns: reporter [RegModel] Memory 'mem.Memory' may not be added to address map 'Backdoor' : they are not in the same block

 

I didn't see anything in any documentation about creating or setting up this backdoor map and I don't really see any way for users to even do that if they wanted to.

 

My user-defined write() function still seems to be called despite the warning.

 

Can someone please enlighten me about the proper way to set up this backdoor map or point me in the direction of an example or some documentation?  I'm missing something.

 

Thanks.