Register model access from C

UVM
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Hi all!
I have UVM-based testbench with, say, an APB bus.
Both C code and internal verilog sequences are used to initialise DUT via this bus. I use UVM register model for this purpose, as adviced in this video:

https://verificationacademy.com/seminars/uvm-recipe-c-based-stimulus-for-uvm

At first initialzation with C code happens, then verilog code randomly reprograms some of the registers.
It seems to me, that eventually C code will not know, what exactly is the state of the registers, and the only way for C code to find it out now, is to make a full read of all the registers from DUT, which is not efficient.

What i would like to have, is for C code to get access to the whole memory with one request and without any activity happening on DUT inputs. So basically i want to access the register model itself from C code. Could anyone please tell me, what is the best way to do it? Have anyone ever encountered such a problem at all?
Thank you!

2

In reply to boryah:

A register model does not exist as a whole memory; that is an illusion created by the hardware.

You can certainly make things more efficient by doing a register.get() of the mirrored value without involving the DUT. You would have to DPI export some SystemVerilog function that you call from C. This function would lookup a handle to a register based on the address. and get its mirrored value.

Another option is having the bus2reg method in the uvm_reg_adaptor call a DPI function that updates a C memory. This essentially create a C memory mirror. You might want to implement this as a sparse memory (associative array) if the register address space is large.