packet_filter: Initial commit

- Added a reusable packet filtering tree
- Added the filter to the monitoring module as an option
- Created the packet_filter project for demonstration purposes of the packet filtering tree

Signed-off-by: Istvan-Zsolt Szekely <[email protected]>

library/drivers/common/filter.sv

@@ -0,0 +1,116 @@
+`include "utils.svh"
+
+package filter_pkg;
+
+  import logger_pkg::*;
+
+  class filter_class;
+
+    protected bit [31:0] position;
+    protected logic [7:0] value;
+    protected bit equals;
+
+    bit result;
+
+    function new(
+      input bit [31:0] position,
+      input logic [7:0] value,
+      input bit equals = 1);
+
+      this.position = position;
+      this.value = value;
+      this.equals = equals;
+      this.result = 0;
+    endfunction: new
+
+    function void apply_filter(input logic [7:0] packet[]);
+      logic [7:0] value;
+
+      value = packet[this.position];
+      for (int i=0; i< $size(value); i++)
+        if (this.value[i] == 1'bx || this.value[i] == 1'bz) continue;
+        else if (this.value[i] != value[i]) begin
+          this.result = !equals;
+          return;
+        end
+
+      this.result = equals;
+      return;
+    endfunction: apply_filter
+
+  endclass: filter_class
+
+
+  class filter_tree_class;
+
+    protected bit filter_type; // 0 - all leaf nodes/cells are evaluated with logical or
+                     // 1 - all leaf nodes/cells are evaluated with logical and
+
+    bit result;
+
+    protected filter_class filter[];
+    filter_tree_class ft[];
+
+    function new(
+      input bit filter_type,
+      input bit [31:0] nr_of_filters,
+      input bit [31:0] nr_of_filter_trees);
+
+      this.filter_type = filter_type;
+      this.result = filter_type;
+      this.filter = new[nr_of_filters];
+      this.ft = new[nr_of_filter_trees];
+    endfunction: new
+
+    function void add_filter(
+      input bit [31:0] filter_nr,
+      input bit [31:0] position,
+      input logic [7:0] value,
+      input bit equals = 1);
+
+      this.filter[filter_nr] = new (position, value, equals);
+    endfunction: add_filter
+
+    function void add_filter_tree(
+      input bit [31:0] filter_tree_nr,
+      input bit filter_type,
+      input bit [31:0] nr_of_filters,
+      input bit [31:0] nr_of_filter_trees);
+
+      this.ft[filter_tree_nr] = new (filter_type, nr_of_filters, nr_of_filter_trees);
+    endfunction: add_filter_tree
+
+    function void remove_filters();
+      this.filter = new[0];
+      this.ft = new[0];
+    endfunction: remove_filters
+
+    task apply_filter(input logic [7:0] packet[]);
+      if (this.filter != null) begin
+        for (int i=0; i<this.filter.size(); i++) begin
+          this.filter[i].apply_filter(packet);
+        end
+        for (int i=0; i<this.filter.size(); i++) begin
+          if (filter_type)
+            this.result = this.result & this.filter[i].result;
+          else
+            this.result = this.result | this.filter[i].result;
+        end
+      end
+
+      if (this.ft != null) begin
+        for (int i=0; i<this.ft.size(); i++) begin
+          this.ft[i].apply_filter(packet);
+        end
+        for (int i=0; i<this.ft.size(); i++) begin
+          if (filter_type)
+            this.result = this.result & this.ft[i].result;
+          else
+            this.result = this.result | this.ft[i].result;
+        end
+      end
+    endtask: apply_filter
+
+  endclass: filter_tree_class
+
+endpackage: filter_pkg

library/drivers/common/scoreboard.sv

@@ -8,11 +8,15 @@ package scoreboard_pkg;
   import logger_pkg::*;
   import x_monitor_pkg::*;
   import mailbox_pkg::*;
+  import filter_pkg::*;
 
   class scoreboard extends xil_component;
 
-    typedef enum bit { CYCLIC=0, ONESHOT } sink_type_t;
-    protected sink_type_t sink_type;
+    typedef enum bit {
+      CYCLIC=0,   // the source data will remain in the buffer after a check
+      ONESHOT     // the source data will be consumed with the sink data
+    } transfer_type_t;
+    protected transfer_type_t transfer_type;
 
     // List of analysis ports from the monitors
     protected x_monitor source_monitor;
@@ -26,6 +30,7 @@ package scoreboard_pkg;
 
     // counters and synchronizers
     protected bit enabled;
+    protected bit filter_enabled;
     protected bit byte_streams_empty_sig;
 
     // protected event end_of_first_cycle;
@@ -34,37 +39,86 @@ package scoreboard_pkg;
     protected event source_transaction_event;
     protected event sink_transaction_event;
 
+    // filter trees
+    protected filter_tree_class filter_tree_source;
+    protected filter_tree_class filter_tree_sink;
+
     // constructor
     function new(input string name);
 
       super.new(name);
 
       this.enabled = 0;
-      this.sink_type = ONESHOT;
+      this.transfer_type = ONESHOT;
       this.source_byte_stream_size = 0;
       this.sink_byte_stream_size = 0;
       this.byte_streams_empty_sig = 1;
+      this.filter_enabled = 0;
 
     endfunction: new
 
     // connect the analysis ports of the monitor to the scoreboard
     function void set_source_stream(
       x_monitor source_monitor);
 
-      this.source_monitor = source_monitor;
+      if (!this.enabled)
+        this.source_monitor = source_monitor;
+      else
+        `ERROR(("Cannot set source monitor while scoreboard is running"));
 
     endfunction: set_source_stream
 
     function void set_sink_stream(
       x_monitor sink_monitor);
 
-      this.sink_monitor = sink_monitor;
-
-    endfunction: set_sink_stream 
+      if (!this.enabled)
+        this.sink_monitor = sink_monitor;
+      else
+        `ERROR(("Cannot set sink monitor while scoreboard is running"));
+
+    endfunction: set_sink_stream
+
+    // enable data filtering
+    function void enable_filtering();
+      if (!this.enabled)
+        this.filter_enabled = 1;
+      else
+        `ERROR(("Cannot enable data filtering while scoreboard is running"));
+    endfunction: enable_filtering
+
+    // disable data filtering
+    function void disable_filtering();
+      if (!this.enabled)
+        this.filter_enabled = 0;
+      else
+        `ERROR(("Cannot disable data filtering while scoreboard is running"));
+    endfunction: disable_filtering
+
+    // set filter tree
+    function void set_filter_tree_source(
+      filter_tree_class filter_tree);
+
+      if (!this.enabled)
+        this.filter_tree_source = filter_tree;
+      else
+        `ERROR(("Cannot change filter tree while scoreboard is running"));
+    endfunction: set_filter_tree_source
+
+    function void set_filter_tree_sink(
+      filter_tree_class filter_tree);
+
+      if (!this.enabled)
+        this.filter_tree_sink = filter_tree;
+      else
+        `ERROR(("Cannot change filter tree while scoreboard is running"));
+    endfunction: set_filter_tree_sink
 
     // run task
     task run();
 
+      if (this.filter_tree_source == null && this.filter_tree_sink == null && this.filter_enabled)
+        `ERROR(("No filter tree is set"));
+
       fork
         this.enabled = 1;
         this.get_source_transaction();
@@ -83,15 +137,15 @@ package scoreboard_pkg;
     endtask: stop
 
     // set sink type
-    function void set_sink_type(input bit sink_type);
+    function void set_transfer_type(input bit transfer_type);
 
       if (!this.enabled) begin
-        this.sink_type = sink_type_t'(sink_type);
+        this.transfer_type = transfer_type_t'(transfer_type);
       end else begin
-        `ERROR(("ERROR Scoreboard: Can not configure sink_type while scoreboard is running."));
+        `ERROR(("ERROR Scoreboard: Can not configure transfer_type while scoreboard is running."));
       end
 
-    endfunction: set_sink_type
+    endfunction: set_transfer_type
 
     // clear source and sink byte streams
     function void clear_streams();
@@ -103,8 +157,8 @@ package scoreboard_pkg;
     endfunction: clear_streams
 
     // get sink type
-    function bit get_sink_type();
-      return this.sink_type;
+    function bit get_transfer_type();
+      return this.transfer_type;
     endfunction
 
     // wait until source and sink byte streams are empty, full check
@@ -118,6 +172,7 @@ package scoreboard_pkg;
     task get_source_transaction();
 
       logic [7:0] source_byte;
+      logic [7:0] packet [];
 
       forever begin
         fork begin
@@ -127,19 +182,31 @@ package scoreboard_pkg;
           join_any
           disable fork;
         end join
+
         if (this.enabled == 0)
           break;
 
         this.source_monitor.get_key();
-        for (int i=0; i<this.source_monitor.mailbox.num(); ++i) begin
+        packet = new [this.source_monitor.mailbox.num()];
+        `INFOV(("Source packet length: %d", packet.size()), 200);
+        for (int i=0; i<packet.size(); ++i) begin
           this.source_monitor.mailbox.get(source_byte);
           this.source_monitor.mailbox.put(source_byte);
-          this.source_byte_stream.push_front(source_byte);
+          packet[i] = source_byte;
         end
-        this.source_byte_stream_size += this.source_monitor.mailbox.num();
-        `INFOV(("Source transaction received, size: %d - %d", this.source_monitor.mailbox.num(), this.source_byte_stream_size), 200);
-        ->>source_transaction_event;
         this.source_monitor.put_key();
+
+        if (this.filter_enabled)
+          this.filter_tree_source.apply_filter(packet);
+
+        if (!this.filter_enabled || this.filter_tree_source.result) begin
+          for (int i=0; i<packet.size(); ++i) begin
+            this.source_byte_stream.push_front(packet[i]);
+          end
+          this.source_byte_stream_size += packet.size();
+          `INFOV(("Source transaction received, size: %d - %d", packet.size(), this.source_byte_stream_size), 200);
+          ->>source_transaction_event;
+        end
       end
 
     endtask: get_source_transaction
@@ -148,6 +215,7 @@ package scoreboard_pkg;
     task get_sink_transaction();
 
       logic [7:0] sink_byte;
+      logic [7:0] packet [];
 
       forever begin
         fork begin
@@ -162,15 +230,26 @@ package scoreboard_pkg;
           break;
 
         this.sink_monitor.get_key();
-        for (int i=0; i<this.sink_monitor.mailbox.num(); ++i) begin
+        packet = new [this.sink_monitor.mailbox.num()];
+        `INFOV(("Sink packet length: %d", packet.size()), 200);
+        for (int i=0; i<packet.size(); ++i) begin
           this.sink_monitor.mailbox.get(sink_byte);
           this.sink_monitor.mailbox.put(sink_byte);
-          this.sink_byte_stream.push_front(sink_byte);
+          packet[i] = sink_byte;
         end
-        this.sink_byte_stream_size += this.sink_monitor.mailbox.num();
-        `INFOV(("Sink transaction received, size: %d - %d", this.sink_monitor.mailbox.num(), this.sink_byte_stream_size), 200);
-        ->>sink_transaction_event;
         this.sink_monitor.put_key();
+
+        if (this.filter_enabled)
+          this.filter_tree_sink.apply_filter(packet);
+
+        if (!this.filter_enabled || this.filter_tree_sink.result) begin
+          for (int i=0; i<packet.size(); ++i) begin
+            this.sink_byte_stream.push_front(packet[i]);
+          end
+          this.sink_byte_stream_size += packet.size();
+          `INFOV(("Sink transaction received, size: %d - %d", packet.size(), this.sink_byte_stream_size), 200);
+          ->>sink_transaction_event;
+        end
       end
 
     endtask: get_sink_transaction
@@ -190,7 +269,7 @@ package scoreboard_pkg;
               (this.sink_byte_stream_size > 0)) begin
           byte_streams_empty_sig = 0;
           source_byte = this.source_byte_stream.pop_back();
-          if (this.sink_type == CYCLIC)
+          if (this.transfer_type == CYCLIC)
             this.source_byte_stream.push_front(source_byte);
           else
             this.source_byte_stream_size--;
@@ -201,10 +280,16 @@ package scoreboard_pkg;
             `ERROR(("Scoreboard failed at: exp %h - rcv %h", source_byte, sink_byte));
           end
         end else begin
-          if ((this.source_byte_stream_size == 0) &&
-              (this.sink_byte_stream_size == 0)) begin
-            byte_streams_empty_sig = 1;
-            ->>byte_streams_empty;
+          if (this.sink_byte_stream_size == 0) begin
+            if (this.transfer_type == CYCLIC) begin
+              byte_streams_empty_sig = 1;
+              ->>byte_streams_empty;
+            end else begin
+              if ((this.source_byte_stream_size == 0)) begin
+                byte_streams_empty_sig = 1;
+                ->>byte_streams_empty;
+              end
+            end
           end
           fork begin
             fork