Changeset 1001 for branches/reconfiguration/modules/vci_local_crossbar/caba/source/src/vci_local_crossbar.cpp

Timestamp:

Jun 16, 2015, 9:24:36 PM (9 years ago)

Author:

cfuguet

Message:

reconf: introducing a hardware barrier in the global-local interface of
the local interconnects.

• This barrier is controlled by a port (barrier enable) in the dspin and vci local interconnects.

• The barrier enable port is connected to a configuration register of the XICU component to allow the software to control this barrier. The barrier is enabled when the barrier enable port value is different of 0xFFFFFFFF. As the configuration register of the XICU component are reset to 0, this barrier is enabled by default.

• This barrier allows to isolate the cluster from the rest of the architecture and only if it self-diagnoses as functional, it release the barrier to communicate with the others.

• The same barrier enable signal is connected to the five local interconnects. Therefore, either all are released or all are disabled.

• If a local initiator or an external initiator sends a packet out or into the cluster respectively, and the barrier is enabled, the packet is dropped.

File:

• branches/reconfiguration/modules/vci_local_crossbar/caba/source/src/vci_local_crossbar.cpp (modified) (12 diffs)

branches/reconfiguration/modules/vci_local_crossbar/caba/source/src/vci_local_crossbar.cpp

@@ -78 +78 @@
     const void*                 m_lt;           // locality table if cmd / id_locality table if rsp
     const bool              m_is_cmd;       // cmd crossbar when true
+    bool                    m_barrier;      // barrier in the global interface is enabled
 
     sc_signal<bool>*            r_allocated;    // for each output port: allocation state 
@@ -97 +98 @@
           m_rt( rt ),
           m_lt( lt ),
-      m_is_cmd( is_cmd )
+      m_is_cmd( is_cmd ),
+      m_barrier( false )
         {
             r_allocated = new sc_signal<bool>[out_size];
@@ -104 +106 @@
             r_bc_count  = new sc_signal<size_t>[in_size];
         } // end constructor 
+
+    //////////////////////////////////
+    void setBarrier(const bool &value)
+    {
+        m_barrier = value;
+    }
 
     ////////////
@@ -147 +155 @@
             }
         }
+        std::cout << " / barrier enable = " << m_barrier;
     } // end print_trace()
 
@@ -190 +199 @@
         for( size_t in = 0 ; in < m_in_size ; in++ )
         {
-            if ( input_port[in]->getVal() )
+            /* drop global-to-local packets when the barrier is enabled */
+            bool write = input_port[in]->getVal();
+            if ( in == (m_in_size - 1) )
+                write = write && !m_barrier;
+
+            if ( write )
             {
                 if ( r_bc_state[in].read() )    // pending broadcast
@@ -237 +251 @@
                 {
                     size_t in = (_in + r_origin[out] + 1) % m_in_size;
-                    if ( input_port[in]->getVal() )
+
+                    /* drop global-to-local packets when the barrier is enabled */
+                    bool write = input_port[in]->getVal();
+                    if ( in == (m_in_size - 1) )
+                        write = write && !m_barrier;
+
+                    if ( write )
                     {
                         pkt_t tmp;
@@ -285 +305 @@
                 pkt_t tmp;
                 tmp.readFrom(*input_port[in]);
+
+                // if the hardware barrier is activated, drop all
+                // local-to-global packets. This is done by consuming every
+                // incoming packet (send the acknowledgement to the input port)
+                // and resetting the cmdval signal to the upper network level.
+                bool read = output_port[out]->getAck();
+                if (out == (m_out_size - 1)) {
+                    read = read || m_barrier;
+                    tmp.set_val(tmp.val() && !m_barrier);
+                }
+
+                ack[in] = read;
                 tmp.writeTo(*output_port[out]);
-                ack[in] = output_port[out]->getAck();
+
                 if ( r_bc_state[in].read() )                    // its a broacast
                 {
@@ -299 +331 @@
             }
         }
+        // Drop all global-to-local packets when the hardware barrier is enabled
+        ack[m_in_size - 1] = ack[m_in_size - 1] || m_barrier;
 
         // Send acknowledges on input ports
@@ -313 +347 @@
     std::cout << "LOCAL_CROSSBAR " << name() << " / ";
     m_cmd_crossbar->print_trace();
-    m_rsp_crossbar->print_trace(); 
+    std::cout << " / ";
+    m_rsp_crossbar->print_trace();
     std::cout << std::endl;
 }
@@ -327 +362 @@
     }
 
+    if (p_barrier_enable != NULL)
+    {
+        const bool enable = (p_barrier_enable->read() != 0xFFFFFFFF);
+        m_cmd_crossbar->setBarrier(enable);
+        m_rsp_crossbar->setBarrier(enable);
+    }
     m_cmd_crossbar->transition( m_ports_to_initiator, m_ports_to_target );
     m_rsp_crossbar->transition( m_ports_to_target, m_ports_to_initiator );
@@ -344 +385 @@
                                   const size_t                       nb_attached_initiators,
                                   const size_t                       nb_attached_targets,
-                              const size_t                       default_target_id )
+                              const size_t                       default_target_id,
+                              const bool                         hardware_barrier )
        : BaseModule(name),
        p_clk("clk"),
@@ -409 +451 @@
         m_ports_to_target[i] = &p_to_target[i];
     m_ports_to_target[nb_attached_targets] = &p_initiator_to_up;
+
+    if (hardware_barrier)
+        p_barrier_enable = new sc_in<uint32_t>("p_barrier_enable");
+    else
+        p_barrier_enable = NULL;
 }