Randomizing sequence items in UVM-SC

[Akhila]

Hi All,

Just wanted to check if the UVM sequence macros (UVM_DO_ON_WITH and UVM_DO_WITH) which support randomizing the sequence object are yet supported by UVM-SC or not? If not, what is the best way to add some randomization in the framework? I saw a post where there are some snippets (link given below) using scvx_rand_object class but I am not sure where to find this(didn't find it in latest SCV and UVM-SC libraries). 

http://nascug.org/events/20th/1-NASCUG20-UVMforSystemC-Karsten.pdf

Also, I get errors while using plain UVM_DO_ON macros. Is it expected? The same works fine with ahb_wr_seq->start(top_env->agent->ahb_sequencer_inst);

I have registered the sequence class with factory already.

UVM_DO_ON(ahb_wr_seq,top_env->agent->ahb_sequencer_inst);

Error message says:

/nfs/iind/disks/ba_bdl_xplore_disk001/am5/UVM_SC/uvm-systemc-1.0-alpha1/src/uvmsc/macros/uvm_sequence_defines.h:150:31: error: expected type-specifier before ‘typeof’
   SEQ_OR_ITEM = dynamic_cast< typeof(SEQ_OR_ITEM) >(create_item(objw__, SEQR, "SEQ_OR_ITEM"));
                               ^
/nfs/iind/disks/ba_bdl_xplore_disk001/am5/UVM_SC/uvm-systemc-1.0-alpha1/src/uvmsc/macros/uvm_sequence_defines.h:115:3: note: in expansion of macro ‘UVM_CREATE_ON’
   UVM_CREATE_ON(SEQ_OR_ITEM, SEQR) \
   ^
/nfs/iind/disks/ba_bdl_xplore_disk001/am5/UVM_SC/uvm-systemc-1.0-alpha1/src/uvmsc/macros/uvm_sequence_defines.h:80:3: note: in expansion of macro ‘UVM_DO_ON_PRI_WITH’
   UVM_DO_ON_PRI_WITH(SEQ_OR_ITEM, SEQR, -1, "")
   ^
ahb_basic_test.h:59:11: note: in expansion of macro ‘UVM_DO_ON’
           UVM_DO_ON(ahb_wr_seq,top_env->agent->ahb_sequencer_inst);
 

Appreciate any help here.

Thanks

Akhila

[Akhila]

Hi All,

I integrated SCV library in my environment and I am able to randomize my sequence item using SCV_EXTENSIONS and scv_smart_ptr. I still couldn't figure out the issue with UVM_DO* macros. But have found a way to randomize the transactions.

 

Thanks

Akhila

[Loki5000]

I'm faced with the same question. But my sequence item is parameterized via template as follow:

template<unsigned DA_WIDTH>
class item_c: public uvm::uvm_sequence_item {
public:
    sc_uint<DA_WIDTH> addr;
...

I'm trying to use SCV_EXTENSIONS and scv_smart_ptr like Akhila do, but my scv_extensions class becomes not fully specialized in my case:

template<unsigned DA_WIDTH>
class scv_extensions<item_c<DA_WIDTH> > : public scv_extensions_base<item_c<DA_WIDTH> > {
public:
    scv_extensions<sc_uint<DA_WIDTH> > addr;
  ...

If understand it right, that will not work.

When I'm trying to create scv_smart_ptr like this:

scv_smart_ptr<item_c<DA_WIDTH> > req("req_item");

I'm receiving the following error:

_scv_smart_ptr.h:88:16: error: invalid new-expression of abstract class type ‘scv_extensions<item_c<16u> >’
     tmp_(&*ext_) {
                ^

Could somebody, please, explain me how to resolve this?

Probably, there are some more appropriate way to create a parameterized sequence item. 

[Philipp A Hartmann]

On 21/04/2017 at 6:01 PM, Loki5000 said:

I'm trying to use SCV_EXTENSIONS and scv_smart_ptr like Akhila do, but my scv_extensions class becomes not fully specialized in my case:

Did you include the required "extensions ctor" in your extension?

template<unsigned DA_WIDTH>
class scv_extensions<item_c<DA_WIDTH> > : public scv_extensions_base<item_c<DA_WIDTH> > {
public:
  scv_extensions<sc_uint<DA_WIDTH> > addr;
  // ...

  SCV_EXTENSIONS_CTOR(item_c<DA_WIDTH>) {
    SCV_FIELD(addr);
    // ...
  }
};

That said, (depending on your compiler) the current implementation of SCV_EXTENSIONS_CTOR is missing some "this->" qualifications in its body to cope with the different lookup rules for templated base classes.

Hope that helps,
  Philipp

[Loki5000]

Yes, I did. Following the compiler (g++) errors descriptions I came to this:

template<>
template<unsigned DA_WIDTH>
class scv_extensions<item_c<DA_WIDTH> > : public scv_extensions_base<item_c<DA_WIDTH> > {
public:
    scv_extensions<op_t> op;
    scv_extensions<sc_uint<DA_WIDTH> > addr;
    scv_extensions<unsigned> delay;

    item_c<DA_WIDTH>* _instance;
    void _set_instance(item_c<DA_WIDTH>* p) { _instance = p; _set_instance_core_wrap(p); }
    item_c<DA_WIDTH>* _get_instance() const { return _instance; }

    SCV_EXTENSIONS_CTOR(item_c<DA_WIDTH>)
{
        SCV_FIELD(op);
        SCV_FIELD(addr);
        SCV_FIELD(delay);
    }
};

I defined another _instance, _set_instance and _get_instance functions. I'm not fully understand how, but it works.

The next problem is that I need one more data field in item_c class.

And it's of std::vector type. I didn't found a way to use std::vector type with SCV. Am I right? It's not possible with SCV?

The only way is to use CRAVE?

[jiqiang]

how to combine crave  rand_obj  class with uvm-sc uvm_sequence_item. when i want to randomize the item?