ruby: change router pipeline stages to 2

This patch changes the router pipeline stages from 4 to 2. The
canonical 4-stage router is conservative while a lower-latency router
with look ahead routing and speculative allocation is well acknowledged.

1 files changed, 4 insertions, 3 deletions

diff --git a/src/mem/ruby/network/garnet/fixed-pipeline/SWallocator_d.cc b/src/mem/ruby/network/garnet/fixed-pipeline/SWallocator_d.cc
index 21fbfe6e5..1e636b589 100644
--- a/src/mem/ruby/network/garnet/fixed-pipeline/SWallocator_d.cc
+++ b/src/mem/ruby/network/garnet/fixed-pipeline/SWallocator_d.cc
@@ -82,6 +82,7 @@ SWallocator_d::wakeup()
 
     clear_request_vector();
     check_for_wakeup();
+    m_router->call_switch();
 
 }
 
@@ -178,10 +179,10 @@ SWallocator_d::arbitrate_outports()
 
                 // remove flit from Input Unit
                 flit_d *t_flit = m_input_unit[inport]->getTopFlit(invc);
-                t_flit->advance_stage(ST_, m_router->curCycle() + Cycles(1));
+                t_flit->advance_stage(ST_, m_router->curCycle());
                 t_flit->set_vc(outvc);
                 t_flit->set_outport(outport);
-                t_flit->set_time(m_router->curCycle() + Cycles(1));
+                t_flit->set_time(m_router->curCycle());
 
                 m_output_unit[outport]->decrement_credit(outvc);
                 m_router->update_sw_winner(inport, t_flit);
@@ -223,7 +224,7 @@ SWallocator_d::check_for_wakeup()
     for (int i = 0; i < m_num_inports; i++) {
         for (int j = 0; j < m_num_vcs; j++) {
             if (m_input_unit[i]->need_stage(j, ACTIVE_, SA_, nextCycle)) {
-                scheduleEvent(Cycles(1));
+                m_router->vcarb_req();
                 return;
             }
         }