Hierachical configuration class

[fbochud]

Hi,

I'm trying to implement my VIP by using configuration classes for the agent and the environment. What is the recommended way of doing this, if I want to override both the agent and its configuration with an extended child definition?

Below is an example of how I think i should be written, but unfortunately, the configuration is not set for the extended agent: (Sorry for the bad increment)

package pkg;

import uvm_pkg::*;

`include "uvm_macros.svh"

/***************************************************

/* configuration that will be used in my base agent

/***************************************************/

class BaseConfig extends uvm_object;

`uvm_object_utils(BaseConfig)

rand int baseconfig_item;

function new (string name = "");

super.new(name);

baseconfig_item = 0;

endfunction

// Standard utility method for a config object or transaction

function string convert2string;

return $sformatf("baseconfig_item = %0d\n", baseconfig_item);

endfunction

endclass: BaseConfig

/***************************************************

/* configuration that will be used in my extended agent

/***************************************************/

class ExtendedConfig extends BaseConfig;

`uvm_object_utils(ExtendedConfig)

rand int extconfig_item;

function new (string name = "");

super.new(name);

extconfig_item = 1;

endfunction

// Standard utility method for a config object or transaction

function string convert2string;

return $sformatf("extconfig_item = %0d, baseconfig_item = %0d\n", extconfig_item, baseconfig_item);

endfunction

endclass: ExtendedConfig

/***************************************************

/* configuration that will be used in my environment,

/* instantiates basically one agent_config per agent,

/****************************************************/

class EnvConfig extends uvm_object;

`uvm_object_utils(EnvConfig)

rand int env_item;

BaseConfig cfg;

function new (string name = "");

super.new(name);

cfg = new();

cfg = BaseConfig::type_id::create("cfg");

env_item = 2;

endfunction

// Standard utility method for a config object or transaction

function string convert2string;

return $sformatf("env_item = %0d, cfg: %s\n", env_item, cfg.convert2string);

endfunction

endclass: EnvConfig

/***************************************************

/* Agent and enviromnent definitions

/****************************************************/

class BaseAgent extends uvm_agent;

`uvm_component_utils(BaseAgent)

// new - constructor

function new (string name, uvm_component parent);

super.new(name, parent);

endfunction : new

function void build_phase(uvm_phase phase);

super.build_phase(phase);

endfunction: build_phase

task run_phase(uvm_phase phase);

phase.raise_objection(this);

`uvm_info("Component A", "hello out there!", UVM_MEDIUM)

phase.drop_objection(this);

endtask

endclass: BaseAgent

class ExtendedAgent extends BaseAgent;

`uvm_component_utils(ExtendedAgent)

ExtendedConfig my_ext_cfg;

// new - constructor

function new (string name, uvm_component parent);

super.new(name, parent);

endfunction : new

function void build_phase(uvm_phase phase);

super.build_phase(phase);

// Get config

if (!uvm_config_db #(ExtendedConfig)::get(this, "", "cfg", my_ext_cfg) )

`uvm_fatal("NOCFG",{"config must be set for: ",get_full_name(),".my_ext_cfg"});

endfunction: build_phase

task run_phase(uvm_phase phase);

phase.raise_objection(this);

`uvm_info("Component B", "hello out there!", UVM_MEDIUM)

`uvm_info("Component B", my_ext_cfg.convert2string, UVM_MEDIUM)

phase.drop_objection(this);

endtask

endclass: ExtendedAgent

class BaseEnv extends uvm_env;

`uvm_component_utils(BaseEnv)

EnvConfig env_cfg;

BaseAgent my_base_agent;

// new - constructor

function new(string name, uvm_component parent);

super.new(name, parent);

endfunction : new

// build

function void build_phase(uvm_phase phase);

super.build_phase(phase);

if(!uvm_config_db#(EnvConfig)::get(this, "", "env_config", env_cfg))

`uvm_fatal("NOCFG",{"config must be set for: ",get_full_name(),".env_cfg"});

// update some baseAgent params

env_cfg.cfg.baseconfig_item = 5;

// forward config to lower component

uvm_config_db #(BaseConfig)::set(this, "cfg", "config", env_cfg.cfg);

my_base_agent = new("agent", null);

my_base_agent = BaseAgent::type_id::create("agent", this);

endfunction : build_phase

endclass: BaseEnv

endpackage

/***************************************************

/* Top module with overrides

/****************************************************/

module test;

import uvm_pkg::*;

import pkg::*;

BaseEnv my_base_env;

EnvConfig env_cfg;

initial begin

// Override my base class with extended functionality

factory.set_type_override_by_type(BaseAgent::get_type(), ExtendedAgent::get_type());

factory.set_type_override_by_type(BaseConfig::get_type(), ExtendedConfig::get_type());

env_cfg = new();

uvm_config_db #(EnvConfig)::set(my_base_env, "*", "env_config", env_cfg);

my_base_env = new("env", null);

run_test();

end

endmodule // test

[janick]

The uvm_config_db() does not know about inheritance and puts the configuration in the BaseConfig table, even though it is an instance of ExtendedConfig. You need to get it using uvm_config_db#(BaseConfig)::get() and $cast() it to ExtendedConfig.

[fbochud]

Thank you for the quick answer. I'm not sure I understood correctly, but here are my changes

1. In the class BaseAgent, I instantiate a base_cfg and run a uvm_config_db #(BaseConfig)::get(this, "", "config", my_cfg)

2. in the class ExtendedAgent, I declare an ExtendedConfig and assign it using $cast(my_ext_cfg, my_cfg);

It seems to work . Any comments?

See Code Below:

/***************************************************

/ Agent and environment definitions

****************************************************/

class BaseAgent extends uvm_agent;

`uvm_component_utils(BaseAgent)

BaseConfig my_cfg;

// new - constructor

function new (string name, uvm_component parent);

super.new(name, parent);

endfunction : new

function void build_phase(uvm_phase phase);

super.build_phase(phase);

// Get config

if (!uvm_config_db #(BaseConfig)::get(this, "", "config", my_cfg) )

`uvm_fatal("NOCFG",{"config must be set for: ",get_full_name(),".my_cfg"});

endfunction: build_phase

task run_phase(uvm_phase phase);

phase.raise_objection(this);

`uvm_info("Component A", "hello out there!", UVM_MEDIUM)

// `uvm_info("Component A", my_cfg.convert2string, UVM_MEDIUM)

phase.drop_objection(this);

endtask

endclass: BaseAgent

class ExtendedAgent extends BaseAgent;

`uvm_component_utils(ExtendedAgent)

ExtendedConfig my_ext_cfg;

// new - constructor

function new (string name, uvm_component parent);

super.new(name, parent);

endfunction : new

function void build_phase(uvm_phase phase);

super.build_phase(phase);

$cast(my_ext_cfg, my_cfg);

endfunction: build_phase

task run_phase(uvm_phase phase);

phase.raise_objection(this);

`uvm_info("Component B", "hello out there!", UVM_MEDIUM)

`uvm_info("Component B", my_ext_cfg.convert2string, UVM_MEDIUM)

phase.drop_objection(this);

endtask

endclass: ExtendedAgent

A last issue is when I try to assign the extconfig_item from the top module (see code below). Not really sure, how I should do this...

module test;

import uvm_pkg::*;

import pkg::*;

BaseEnv my_base_env;

EnvConfig env_cfg;

initial begin

// Override my base class with extended functionality

factory.set_type_override_by_type(BaseAgent::get_type(), ExtendedAgent::get_type());

factory.set_type_override_by_type(BaseConfig::get_type(), ExtendedConfig::get_type());

env_cfg = new();

env_cfg.env_item = 0; // Ok

env_cfg.cfg.baseconfig_item = 10; // Ok

env_cfg.cfg.extconfig_item = 11; // Error, Could not find member 'extconfig_item' in class 'BaseConfig'

uvm_config_db #(EnvConfig)::set(my_base_env, "*", "env_config", env_cfg);

my_base_env = new("env", null);

run_test();

end

endmodule // test

[fbochud]

Correction, the last code compiles, but it does not work as desired.

Setting the env_cfg params in "module test" doesn't update the actual parameters in the agents. At the test start baseconfig_item = 5 instead of the expected 10. Any suggestions?

[fbochud]

Re-Correction: baseconfig_item = 5 is correct since it is set in the env BaseEnv constructor. Sorry for last post. Remains the last issue with assign extconfig_item from the top module.

[fbochud]

By creating the env_cfg and the extended agent_cfg in the top, one will be able to assign the extconfig items:

[...]

// Configurations

EnvConfig env_cfg;

ExtendedConfig agent_cfg;

initial begin

// Override my base class with extended functionality

factory.set_type_override_by_type(BaseAgent::get_t ype(), ExtendedAgent::get_type());

agent_cfg = ext_audio_config::type_id::create("agent_cfg");

agent_cfg.baseconfig_item = 20;

agent_cfg.extconfig_item = 10;

env_cfg = EnvConfig::type_id::create("env_cfg");

env_cfg.env_item = 15;

env_cfg.cfg = agent_cfg;

uvm_config_db #(EnvConfig)::set(this, "*", "env_config", env_cfg);

[...]