uvm_component

Creates a new component with the given leaf instance name and handle to to its parent.  If the component is a top-level component (i.e. it is created in a static module or interface), parent should be null.

The component will be inserted as a child of the parent object, if any.  If parent already has a child by the given name, an error is produced.

If parent is null, then the component will become a child of the implicit top-level component, uvm_top.

All classes derived from uvm_component must call super.new(name,parent).

Returns a handle to this component’s parent, or null if it has no parent.

Returns the full hierarchical name of this object.  The default implementation concatenates the hierarchical name of the parent, if any, with the leaf name of this object, as given by uvm_object::get_name.

This function populates the end of the children array with the list of this component’s children.

uvm_component array[$];
my_comp.get_children(array);
foreach(array[i])
  do_something(array[i]);

These methods are used to iterate through this component’s children, if any.  For example, given a component with an object handle, comp, the following code calls uvm_object::print for each child:

string name;
uvm_component child;
if (comp.get_first_child(name))
  do begin
    child = comp.get_child(name);
    child.print();
  end while (comp.get_next_child(name));

Returns the number of this component’s children.

Returns 1 if this component has a child with the given name, 0 otherwise.

Looks for a component with the given hierarchical name relative to this component.  If the given name is preceded with a ‘.’  (dot), then the search begins relative to the top level (absolute lookup).  The handle of the matching component is returned, else null.  The name must not contain wildcards.

Returns the component’s depth from the root level. uvm_top has a depth of 0.  The test and any other top level components have a depth of 1, and so on.

The uvm_build_phase phase implementation method.

Any override should call super.build_phase(phase) to execute the automatic configuration of fields registed in the component by calling apply_config_settings.  To turn off automatic configuration for a component, do not call super.build_phase(phase).

This method should never be called directly.

The uvm_connect_phase phase implementation method.

This method should never be called directly.

The uvm_end_of_elaboration_phase phase implementation method.

This method should never be called directly.

The uvm_start_of_simulation_phase phase implementation method.

This method should never be called directly.

The uvm_run_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  Thn the phase will automatically ends once all objections are dropped using phase.drop_objection().

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

The run_phase task should never be called directly.

The uvm_pre_reset_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_reset_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_post_reset_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_pre_configure_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_configure_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_post_configure_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_pre_main_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_main_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_post_main_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_pre_shutdown_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_shutdown_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_post_shutdown_phase phase implementation method.

This task returning or not does not indicate the end or persistence of this phase.  It is necessary to raise an objection using phase.raise_objection() to cause the phase to persist.  Once all components have dropped their respective objection using phase.drop_objection(), or if no components raises an objection, the phase is ended.

Any processes forked by this task continue to run after the task returns, but they will be killed once the phase ends.

This method should not be called directly.

The uvm_extract_phase phase implementation method.

This method should never be called directly.

The uvm_check_phase phase implementation method.

This method should never be called directly.

The uvm_report_phase phase implementation method.

This method should never be called directly.

The uvm_final_phase phase implementation method.

This method should never be called directly.

Invoked at the start of each phase.  The phase argument specifies the phase being started.  Any threads spawned in this callback are not affected when the phase ends.

Invoked when all objections to ending the given phase have been dropped, thus indicating that phase is ready to end.  All this component’s processes forked for the given phase will be killed upon return from this method.  Components needing to consume delta cycles or advance time to perform a clean exit from the phase may raise the phase’s objection.

phase.raise_objection(this,"Reason");

This effectively resets the wait-for-all-objections-dropped loop for phase.  It is the responsibility of this component to drop the objection once it is ready for this phase to end (and processes killed).

Invoked at the end of each phase.  The phase argument specifies the phase that is ending.  Any threads spawned in this callback are not affected when the phase ends.

Apply a phase domain to this component and, if hier is set, recursively to all its children.

Calls the virtual define_domain method, which derived components can override to augment or replace the domain definition of ita base class.

Return handle to the phase domain set on this component

Builds custom phase schedules into the provided domain handle.

This method is called by set_domain, which integrators use to specify this component belongs in a domain apart from the default ‘uvm’ domain.

Custom component base classes requiring a custom phasing schedule can augment or replace the domain definition they inherit by overriding <defined_domain>.  To augment, overrides would call super.define_domain().  To replace, overrides would not call super.define_domain().

The default implementation adds a copy of the uvm phasing schedule to the given domain, if one doesn’t already exist, and only if the domain is currently empty.

Calling set_domain with the default uvm domain (see <uvm_domain::get_uvm_domain>) on a component with no define_domain override effectively reverts the that component to using the default uvm domain.  This may be useful if a branch of the testbench hierarchy defines a custom domain, but some child sub-branch should remain in the default uvm domain, call set_domain with a new domain instance handle with hier set.  Then, in the sub-branch, call set_domain with the default uvm domain handle, obtained via uvm_domain::get_uvm_domain().

Alternatively, the integrator may define the graph in a new domain externally, then call set_domain to apply it to a component.

Override the default implementation for a phase on this component (tree) with a custom one, which must be created as a singleton object extending the default one and implementing required behavior in exec and traverse methods

The hier specifies whether to apply the custom functor to the whole tree or just this component.

Suspend this component.

This method must be implemented by the user to suspend the component according to the protocol and functionality it implements.  A suspended component can be subsequently resumed using resume().

Resume this component.

This method must be implemented by the user to resume a component that was previously suspended using suspend().  Some component may start in the suspended state and may need to be explicitly resumed.

Processes all port, export, and imp connections.  Checks whether each port’s min and max connection requirements are met.

It is called just before the end_of_elaboration phase.

Users should not call directly.

Calling set_config_* causes configuration settings to be created and placed in a table internal to this component.  There are similar global methods that store settings in a global table.  Each setting stores the supplied inst_name, field_name, and value for later use by descendent components during their construction.  (The global table applies to all components and takes precedence over the component tables.)

When a descendant component calls a get_config_* method, the inst_name and field_name provided in the get call are matched against all the configuration settings stored in the global table and then in each component in the parent hierarchy, top-down.  Upon the first match, the value stored in the configuration setting is returned.  Thus, precedence is global, following by the top-level component, and so on down to the descendent component’s parent.

These methods work in conjunction with the get_config_* methods to provide a configuration setting mechanism for integral, string, and uvm_object-based types.  Settings of other types, such as virtual interfaces and arrays, can be indirectly supported by defining a class that contains them.

Both inst_name and field_name may contain wildcards.

• For set_config_int, value is an integral value that can be anything from 1 bit to 4096 bits.
• For set_config_string, value is a string.
• For set_config_object, value must be an uvm_object-based object or null.  Its clone argument specifies whether the object should be cloned.  If set, the object is cloned both going into the table (during the set) and coming out of the table (during the get), so that multiple components matched to the same setting (by way of wildcards) do not end up sharing the same object.

See get_config_int, get_config_string, and get_config_object for information on getting the configurations set by these methods.

These methods retrieve configuration settings made by previous calls to their set_config_* counterparts.  As the methods’ names suggest, there is direct support for integral types, strings, and objects.  Settings of other types can be indirectly supported by defining an object to contain them.

Configuration settings are stored in a global table and in each component instance.  With each call to a get_config_* method, a top-down search is made for a setting that matches this component’s full name and the given field_name.  For example, say this component’s full instance name is top.u1.u2.  First, the global configuration table is searched.  If that fails, then it searches the configuration table in component ‘top’, followed by top.u1.

The first instance/field that matches causes value to be written with the value of the configuration setting and 1 is returned.  If no match is found, then value is unchanged and the 0 returned.

Calling the get_config_object method requires special handling.  Because value is an output of type uvm_object, you must provide an uvm_object handle to assign to (not a derived class handle).  After the call, you can then $cast to the actual type.

For example, the following code illustrates how a component designer might call upon the configuration mechanism to assign its data object property, whose type myobj_t derives from uvm_object.

class mycomponent extends uvm_component;

  local myobj_t data;

  function void build_phase(uvm_phase phase);
    uvm_object tmp;
    super.build_phase(phase);
    if(get_config_object("data", tmp))
      if (!$cast(data, tmp))
        $display("error! config setting for 'data' not of type myobj_t");
      endfunction
    ...

The above example overrides the build_phase method.  If you want to retain any base functionality, you must call super.build_phase(uvm_phase phase).

The clone bit clones the data inbound.  The get_config_object method can also clone the data outbound.

See Members for information on setting the global configuration table.

Check all configuration settings in a components configuration table to determine if the setting has been used, overridden or not used.  When recurse is 1 (default), configuration for this and all child components are recursively checked.  This function is automatically called in the check phase, but can be manually called at any time.

To get all configuration information prior to the run phase, do something like this in your top object:

function void start_of_simulation_phase(uvm_phase phase);
  check_config_usage();
endfunction

Searches for all config settings matching this component’s instance path.  For each match, the appropriate set_*_local method is called using the matching config setting’s field_name and value.  Provided the set_*_local method is implemented, the component property associated with the field_name is assigned the given value.

This function is called by uvm_component::build_phase.

The apply_config_settings method determines all the configuration settings targeting this component and calls the appropriate set_*_local method to set each one.  To work, you must override one or more set_*_local methods to accommodate setting of your component’s specific properties.  Any properties registered with the optional `uvm_*_field macros do not require special handling by the set_*_local methods; the macros provide the set_*_local functionality for you.

If you do not want apply_config_settings to be called for a component, then the build_phase() method should be overloaded and you should not call super.build_phase(phase).  Likewise, apply_config_settings can be overloaded to customize automated configuration.

When the verbose bit is set, all overrides are printed as they are applied.  If the component’s print_config_matches property is set, then apply_config_settings is automatically called with verbose = 1.

Called without arguments, print_config_settings prints all configuration information for this component, as set by previous calls to set_config_*.  The settings are printing in the order of their precedence.

If field is specified and non-empty, then only configuration settings matching that field, if any, are printed.  The field may not contain wildcards.

If comp is specified and non-null, then the configuration for that component is printed.

If recurse is set, then configuration information for all comp’s children and below are printed as well.

This function has been deprecated.  Use print_config instead.

Print_config_settings prints all configuration information for this component, as set by previous calls to set_config_* and exports to the resources pool.  The settings are printing in the order of their precedence.

If recurse is set, then configuration information for all children and below are printed as well.

if audit is set then the audit trail for each resource is printed along with the resource name and value

Operates the same as print_config except that the audit bit is forced to 1.  This interface makes user code a bit more readable as it avoids multiple arbitrary bit settings in the argument list.

If recurse is set, then configuration information for all children and below are printed as well.

The raised callback is called when this or a descendant of this component instance raises the specfied objection.  The source_obj is the object that originally raised the objection.  The description is optionally provided by the source_obj to give a reason for raising the objection.  The count indicates the number of objections raised by the source_obj.

The dropped callback is called when this or a descendant of this component instance drops the specfied objection.  The source_obj is the object that originally dropped the objection.  The description is optionally provided by the source_obj to give a reason for dropping the objection.  The count indicates the number of objections dropped by the the source_obj.

The all_droppped callback is called when all objections have been dropped by this component and all its descendants.  The source_obj is the object that dropped the last objection.  The description is optionally provided by the source_obj to give a reason for raising the objection.  The count indicates the number of objections dropped by the the source_obj.

A convenience function for uvm_factory::create_component_by_name, this method calls upon the factory to create a new child component whose type corresponds to the preregistered type name, requested_type_name, and instance name, name.  This method is equivalent to:

factory.create_component_by_name(requested_type_name,
                                 get_full_name(), name, this);

If the factory determines that a type or instance override exists, the type of the component created may be different than the requested type.  See set_type_override and set_inst_override.  See also uvm_factory for details on factory operation.

A convenience function for uvm_factory::create_object_by_name, this method calls upon the factory to create a new object whose type corresponds to the preregistered type name, requested_type_name, and instance name, name.  This method is equivalent to:

factory.create_object_by_name(requested_type_name,
                              get_full_name(), name);

If the factory determines that a type or instance override exists, the type of the object created may be different than the requested type.  See uvm_factory for details on factory operation.

A convenience function for uvm_factory::set_type_override_by_type, this method registers a factory override for components and objects created at this level of hierarchy or below.  This method is equivalent to:

factory.set_type_override_by_type(original_type, override_type,replace);

The relative_inst_path is relative to this component and may include wildcards.  The original_type represents the type that is being overridden.  In subsequent calls to uvm_factory::create_object_by_type or uvm_factory::create_component_by_type, if the requested_type matches the original_type and the instance paths match, the factory will produce the override_type.

The original and override type arguments are lightweight proxies to the types they represent.  See set_inst_override_by_type for information on usage.

A convenience function for uvm_factory::set_inst_override_by_type, this method registers a factory override for components and objects created at this level of hierarchy or below.  In typical usage, this method is equivalent to:

factory.set_inst_override_by_type({get_full_name(),".",
                                   relative_inst_path},
                                   original_type,
                                   override_type);

The relative_inst_path is relative to this component and may include wildcards.  The original_type represents the type that is being overridden.  In subsequent calls to uvm_factory::create_object_by_type or uvm_factory::create_component_by_type, if the requested_type matches the original_type and the instance paths match, the factory will produce the override_type.

The original and override types are lightweight proxies to the types they represent.  They can be obtained by calling type::get_type(), if implemented by type, or by directly calling type::type_id::get(), where type is the user type and type_id is the name of the typedef to uvm_object_registry #(T,Tname) or uvm_component_registry #(T,Tname).

If you are employing the `uvm_*_utils macros, the typedef and the get_type method will be implemented for you.  For details on the utils macros refer to Utility and Field Macros for Components and Objects.

The following example shows `uvm_*_utils usage

class comp extends uvm_component;
  `uvm_component_utils(comp)
  ...
endclass

class mycomp extends uvm_component;
  `uvm_component_utils(mycomp)
  ...
endclass

class block extends uvm_component;
  `uvm_component_utils(block)
  comp c_inst;
  virtual function void build_phase(uvm_phase phase);
    set_inst_override_by_type("c_inst",comp::get_type(),
                                       mycomp::get_type());
  endfunction
  ...
endclass

A convenience function for uvm_factory::set_type_override_by_name, this method configures the factory to create an object of type override_type_name whenever the factory is asked to produce a type represented by original_type_name.  This method is equivalent to:

factory.set_type_override_by_name(original_type_name,
                                  override_type_name, replace);

The original_type_name typically refers to a preregistered type in the factory.  It may, however, be any arbitrary string.  Subsequent calls to create_component or create_object with the same string and matching instance path will produce the type represented by override_type_name.  The override_type_name must refer to a preregistered type in the factory.

A convenience function for uvm_factory::set_inst_override_by_type, this method registers a factory override for components created at this level of hierarchy or below.  In typical usage, this method is equivalent to:

factory.set_inst_override_by_name({get_full_name(),".",
                                   relative_inst_path},
                                    original_type_name,
                                   override_type_name);

The relative_inst_path is relative to this component and may include wildcards.  The original_type_name typically refers to a preregistered type in the factory.  It may, however, be any arbitrary string.  Subsequent calls to create_component or create_object with the same string and matching instance path will produce the type represented by override_type_name.  The override_type_name must refer to a preregistered type in the factory.

This factory debug method performs the same lookup process as create_object and create_component, but instead of creating an object, it prints information about what type of object would be created given the provided arguments.

These methods recursively associate the specified verbosity with reports of the given severity, id, or severity-id pair.  An verbosity associated with a particular severity-id pair takes precedence over an verbosity associated with id, which takes precedence over an an verbosity associated with a severity.

For a list of severities and their default verbosities, refer to uvm_report_handler.

These methods recursively associate the specified action with reports of the given severity, id, or severity-id pair.  An action associated with a particular severity-id pair takes precedence over an action associated with id, which takes precedence over an an action associated with a severity.

For a list of severities and their default actions, refer to uvm_report_handler.

These methods recursively associate the specified FILE descriptor with reports of the given severity, id, or severity-id pair.  A FILE associated with a particular severity-id pair takes precedence over a FILE associated with id, which take precedence over an a FILE associated with a severity, which takes precedence over the default FILE descriptor.

For a list of severities and other information related to the report mechanism, refer to uvm_report_handler.

This method recursively sets the maximum verbosity level for reports for this component and all those below it.  Any report from this component subtree whose verbosity exceeds this maximum will be ignored.

See uvm_report_handler for a list of predefined message verbosity levels and their meaning.

This callback is executed when the message system is executing a UVM_EXIT action.  The exit action causes an immediate termination of the simulation, but the pre_abort callback hook gives components an opportunity to provide additional information to the user before the termination happens.  For example, a test may want to executed the report function of a particular component even when an error condition has happened to force a premature termination you would write a function like:

function void mycomponent::pre_abort();
  report();
endfunction

The pre_abort() callback hooks are called in a bottom-up fashion.

This function marks the acceptance of a transaction, tr, by this component.  Specifically, it performs the following actions:

• Calls the tr’s uvm_transaction::accept_tr method, passing to it the accept_time argument.
• Calls this component’s do_accept_tr method to allow for any post-begin action in derived classes.
• Triggers the component’s internal accept_tr event.  Any processes waiting on this event will resume in the next delta cycle.

The accept_tr method calls this function to accommodate any user-defined post-accept action.  Implementations should call super.do_accept_tr to ensure correct operation.

This function marks the start of a transaction, tr, by this component.  Specifically, it performs the following actions:

• Calls tr’s uvm_transaction::begin_tr method, passing to it the begin_time argument.  The begin_time should be greater than or equal to the accept time.  By default, when begin_time = 0, the current simulation time is used.

If recording is enabled (recording_detail != UVM_OFF), then a new database-transaction is started on the component’s transaction stream given by the stream argument.  No transaction properties are recorded at this time.

• Calls the component’s do_begin_tr method to allow for any post-begin action in derived classes.
• Triggers the component’s internal begin_tr event.  Any processes waiting on this event will resume in the next delta cycle.

A handle to the transaction is returned.  The meaning of this handle, as well as the interpretation of the arguments stream_name, label, and desc are vendor specific.

This function marks the start of a child transaction, tr, by this component.  Its operation is identical to that of begin_tr, except that an association is made between this transaction and the provided parent transaction.  This association is vendor-specific.

The begin_tr and begin_child_tr methods call this function to accommodate any user-defined post-begin action.  Implementations should call super.do_begin_tr to ensure correct operation.

This function marks the end of a transaction, tr, by this component.  Specifically, it performs the following actions:

• Calls tr’s uvm_transaction::end_tr method, passing to it the end_time argument.  The end_time must at least be greater than the begin time.  By default, when end_time = 0, the current simulation time is used.

The transaction’s properties are recorded to the database-transaction on which it was started, and then the transaction is ended.  Only those properties handled by the transaction’s do_record method (and optional `uvm_*_field macros) are recorded.

• Calls the component’s do_end_tr method to accommodate any post-end action in derived classes.
• Triggers the component’s internal end_tr event.  Any processes waiting on this event will resume in the next delta cycle.

The free_handle bit indicates that this transaction is no longer needed.  The implementation of free_handle is vendor-specific.

The end_tr method calls this function to accommodate any user-defined post-end action.  Implementations should call super.do_end_tr to ensure correct operation.

This function marks an error transaction by a component.  Properties of the given uvm_object, info, as implemented in its uvm_object::do_record method, are recorded to the transaction database.

An error_time of 0 indicates to use the current simulation time.  The keep_active bit determines if the handle should remain active.  If 0, then a zero-length error transaction is recorded.  A handle to the database-transaction is returned.

Interpretation of this handle, as well as the strings stream_name, label, and desc, are vendor-specific.

This function marks an event transaction by a component.

An event_time of 0 indicates to use the current simulation time.

A handle to the transaction is returned.  The keep_active bit determines if the handle may be used for other vendor-specific purposes.

The strings for stream_name, label, and desc are vendor-specific identifiers for the transaction.