sim[sink/slave]: added permanent stall

Signed-off-by: Tomasz Włostowski <tomasz.wlostowski@cern.ch>

sim/eth_packet.svh

@@ -388,6 +388,8 @@ virtual class EthPacketSink;
    static int _null  = 0;
    
    pure virtual function int poll();
+   pure virtual function int permanent_stall_enable();
+   pure virtual function int permanent_stall_disable();
    pure virtual task recv(ref EthPacket pkt, ref int result = _null);      
    
 endclass // EthPacketSink

sim/if_wb_slave.svh

@@ -63,8 +63,11 @@ interface IWishboneSlave
       real stall_prob;
    } settings;
 
+   int permanent_stall = 0;
 
    function automatic int _poll(); return poll(); endfunction
+   function automatic int _permanent_stall_enable();  return permanent_stall_enable(); endfunction
+   function automatic int _permanent_stall_disable(); return permanent_stall_disable(); endfunction
    task automatic _get(ref wb_cycle_t xfer); get(xfer); endtask
 
    class CIWBSlaveAccessor extends CWishboneAccessor;
@@ -72,7 +75,15 @@ interface IWishboneSlave
       function automatic int poll();
          return _poll();
       endfunction
-      
+
+      function automatic int permanent_stall_enable();
+         return _permanent_stall_enable();
+      endfunction
+
+      function automatic int permanent_stall_disable();
+         return _permanent_stall_disable();
+      endfunction     
+  
       task get(ref wb_cycle_t xfer);
          _get(xfer);
       endtask
@@ -88,7 +99,18 @@ interface IWishboneSlave
       tmp  = new;
       return tmp;
    endfunction // get_accessor
-      
+     
+   function automatic int permanent_stall_enable();
+      permanent_stall = 1;
+      $display("permanent stall ON");
+      return permanent_stall;
+   endfunction
+
+   function automatic int permanent_stall_disable();
+      permanent_stall = 0;
+      $display("permanent stall OFF");
+      return permanent_stall;
+   endfunction 
    
    function automatic int poll();
       return c_queue.size() != 0;
@@ -152,7 +174,10 @@ interface IWishboneSlave
    
    task pipelined_fsm();
 
-      if(settings.gen_random_stalls)
+      // ML
+      if(permanent_stall)
+	stall               <= 1;
+      else if(settings.gen_random_stalls)
 	gen_random_stalls();
       else
         stall               <= 0;

sim/if_wishbone_accessor.svh

@@ -21,6 +21,16 @@ virtual class CWishboneAccessor extends CBusAccessor;
    virtual function automatic int poll();
       return 0;
    endfunction // poll
+   
+   // ML stuff [slave only]
+   virtual function automatic int  permanent_stall_enable();
+     $display("CWisboneAccessor: permanent_stall: ON");
+   endfunction;
+
+   // ML stuff [slave only]
+   virtual function automatic int  permanent_stall_disable();
+     $display("CWisboneAccessor: permanent_stall: OFF");
+   endfunction;
 
    // [slave only] adds a simulation event (e.g. a forced STALL, RETRY, ERROR)
    // evt = event type (STALL, ERROR, RETRY)

sim/wb_packet_sink.svh

@@ -21,6 +21,13 @@ class WBPacketSink extends EthPacketSink;
       return m_acc.poll();
       endfunction // poll
 
+   function int permanent_stall_enable();
+     return m_acc.permanent_stall_enable();
+   endfunction  
+   function int permanent_stall_disable();
+     return m_acc.permanent_stall_disable();
+   endfunction  
+
    protected task decode_status(uint64_t stat, ref EthPacket pkt);
       if(stat & 'h2)
        pkt.error      = 1'b1;