problem about uvm_config_db

[mrforever]

Hi all,

 

Usually we use uvm_config_db::set from the higher hierarchy module and uvm_config_db::get in the lower hierarchy module, Can we use uvm_config_db::set and uvm_config_db::get from the opposite direction?

 

Regards

mrforever

[dave_59]

Sure, Instead of using this for the context of the uvm_config_db#()::set(this,...), you can use null, uvm_root::get(), or use find() to get a higher level context. As long as the get() call is in a later phase than the set() call, this should work.

[mrforever]

Sure, Instead of using this for the context of the uvm_config_db#()::set(this,...), you can use null, uvm_root::get(), or use find() to get a higher level context. As long as the get() call is in a later phase than the set() call, this should work.

 

Hi dave,

Thanks for your reply. I have other two questions:

1. If it is workable as you saying, then how can i use find() to get a higher level context?

2. I think uvm_config_db#()::set() and uvm_config_db#()::get() are static functions. If i want to use them to pass uvm_event type, can it work when the context where the uvm_config_db#()::get() is receives one triggered uvm_event object in the run time?

[uwes]

uvm_config_db is just a typed key-value store. the key is made from (context,path,field). context is a reference to a uvm_component (any method will do (this,null, find_component(),get_parent(),get_parent_sequencer() but also just a path like my_parent.some_subcomponent.somesubsubcomponent).

 

you can share the handle to a uvm_event via the config db. everyone would see the same uvm_event object and therefore any event raised in there would be visible in all other places.

 

/uwe 

[mrforever]

uvm_config_db is just a typed key-value store. the key is made from (context,path,field). context is a reference to a uvm_component (any method will do (this,null, find_component(),get_parent(),get_parent_sequencer() but also just a path like my_parent.some_subcomponent.somesubsubcomponent).

 

you can share the handle to a uvm_event via the config db. everyone would see the same uvm_event object and therefore any event raised in there would be visible in all other places.

 

/uwe 

 

Hi uwe,

Thanks for your reply, I will have a try. I have two questions to ask you.

1. Can it use uvm_config_db#()::set() or uvm_config_db#()::get() in uvm_object?

2. How can i check or debug the uvm_config_db mechanism if it doesn't work correctly?

Thanks in advance!

[uwes]

Hi uwe,

Thanks for your reply, I will have a try. I have two questions to ask you.

1. Can it use uvm_config_db#()::set() or uvm_config_db#()::get() in uvm_object?

2. How can i check or debug the uvm_config_db mechanism if it doesn't work correctly?

Thanks in advance!

 

#1 you can use a static call anywhere (in contrast non-static calls have to be invoked on an object)

#2 you can enable read/write trace and audit, you can dump the whole database, you can trace via +UVM_CONFIG_DB_TRACE, you can find written-but-not-read data in the config-db. all of this should help to figure out where the issue is (mismatching key issues, mismatching type issues, ordering/prio/precedence issue)

[mrforever]

#1 you can use a static call anywhere (in contrast non-static calls have to be invoked on an object)

#2 you can enable read/write trace and audit, you can dump the whole database, you can trace via +UVM_CONFIG_DB_TRACE, you can find written-but-not-read data in the config-db. all of this should help to figure out where the issue is (mismatching key issues, mismatching type issues, ordering/prio/precedence issue)

 

Hi uwes,

Thanks very much. I will have a try.