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[/] [srdydrdy_lib/] [trunk/] [examples/] [bridge/] [rtl/] [fib_lookup_fsm.v] - Blame information for rev 13

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module fib_lookup_fsm
  (/*AUTOARG*/
  // Outputs
  lpp_drdy, ft_wdata, ft_rd_en, ft_wr_en, ft_addr, lout_data,
  lout_srdy, lout_dst_vld,
  // Inputs
  clk, reset, lpp_data, lpp_srdy, ft_rdata, lout_drdy
  );
 
  input clk, reset;
 
  input [`PAR_DATA_SZ-1:0] lpp_data;
  input                    lpp_srdy;
  output reg               lpp_drdy;
 
  input [`FIB_ENTRY_SZ-1:0]       ft_rdata;
  output reg [`FIB_ENTRY_SZ-1:0]  ft_wdata;
  output reg                      ft_rd_en, ft_wr_en;
  output reg [`FIB_ASZ-1:0]       ft_addr;
 
  output reg [`NUM_PORTS-1:0]     lout_data;
  output reg                      lout_srdy;
  input                           lout_drdy;
  output [`NUM_PORTS-1:0]         lout_dst_vld;
 
  wire [`FIB_ASZ-1:0]             hf_out;
  reg [47:0]                      hf_in;
 
  wire [`NUM_PORTS-1:0]           source_port_mask;
 
  reg [`FIB_ASZ-1:0]              init_ctr, nxt_init_ctr;
  reg [4:0]                       state, nxt_state;
 
  assign source_port_mask = 1 << lpp_data[`PAR_SRCPORT];
 
  basic_hashfunc #(48, `FIB_ENTRIES) hashfunc
    (
     // Outputs
     .hf_out                            (hf_out),
     // Inputs
     .hf_in                             (hf_in));
 
  localparam s_idle = 0, s_da_lookup = 1, s_sa_lookup = 2,
    s_init0 = 3, s_init1 = 4;
  localparam ns_idle = 1, ns_da_lookup = 2, ns_sa_lookup = 4,
    ns_init0 = 8, ns_init1 = 16;
 
  // send all results back to their originating port
  assign lout_dst_vld = source_port_mask;
 
  reg                             amux;
 
  always @*
    begin
      case (amux)
 
        1 : ft_addr = init_ctr;
      endcase // case (amux)
    end
 
  always @*
    begin
      hf_in = 0;
      nxt_state = state;
      ft_rd_en = 0;
      ft_wr_en = 0;
      amux = 0;
      lout_data = 0;
      lout_srdy = 0;
      lpp_drdy = 0;
      nxt_init_ctr = init_ctr;
 
      case (1'b1)
        state[s_idle] :
          begin
            // DA lookup
            if (lpp_data[`PAR_MACDA] & `MULTICAST)
              begin
                // flood the packet, don't bother to do DA lookup
                lout_data = ~source_port_mask;
                lout_srdy = 1;
                if (lout_drdy)
                  nxt_state = ns_sa_lookup;
              end
            else if (lpp_srdy)
              begin
                hf_in = lpp_data[`PAR_MACDA];
                ft_rd_en = 1;
                nxt_state = ns_da_lookup;
              end
          end
 
        // results from DA lookup are available this
        // state.  Make forwarding decision at this
        // point.
        state[s_da_lookup] :
          begin
            // no match, flood packet
            if (ft_rdata[`FIB_AGE] == 0)
              begin
                lout_data = ~source_port_mask;
              end
            else
              begin
                lout_data = (1 << ft_rdata[`FIB_PORT]) & ~source_port_mask;
              end
 
            lout_srdy = 1;
            if (lout_drdy)
              nxt_state = ns_sa_lookup;
          end // case: state[s_da_lookup]
 
        // blind write out MACSA to FIB table
        // will bump out current occupant and update
        state[s_sa_lookup] :
          begin
            ft_wr_en = 1;
            hf_in = lpp_data[`PAR_MACSA];
            ft_wdata[`FIB_MACADDR] = lpp_data[`PAR_MACSA];
            ft_wdata[`FIB_AGE]  = `FIB_MAX_AGE;
            ft_wdata[`FIB_PORT] = lpp_data[`PAR_SRCPORT];
            nxt_state = ns_idle;
            lpp_drdy = 1;
          end
 
        state[s_init0] :
          begin
            nxt_init_ctr = 0;
            nxt_state = ns_init1;
          end
 
        state[s_init1] :
          begin
            nxt_init_ctr = init_ctr + 1;
            ft_wr_en = 1;
            amux = 1;
            ft_wdata = 0;
            if (init_ctr == (`FIB_ENTRIES-1))
              nxt_state = ns_idle;
          end
 
        default :
          nxt_state = ns_idle;
      endcase // case (1'b1)
    end // always @ *
 
  always @(posedge clk)
    begin
      if (reset)
        begin
          init_ctr <= #1 0;
          state    <= #1 ns_init0;
        end
      else
        begin
          init_ctr <= #1 nxt_init_ctr;
          state    <= #1 nxt_state;
        end
    end
 
endmodule // fib_lookup_fsm

Line No.	Rev	Author	Line
1	4	ghutchis	`module fib_lookup_fsm`
2			`(/AUTOARG/`
3			`// Outputs`
4	5	ghutchis	`lpp_drdy, ft_wdata, ft_rd_en, ft_wr_en, ft_addr, lout_data,`
5			`lout_srdy, lout_dst_vld,`
6	4	ghutchis	`// Inputs`
7			`clk, reset, lpp_data, lpp_srdy, ft_rdata, lout_drdy`
8			`);`
9
10			`input clk, reset;`
11
12			input [`PAR_DATA_SZ-1:0] lpp_data;
13			`input lpp_srdy;`
14			`output reg lpp_drdy;`
15
16			input [`FIB_ENTRY_SZ-1:0] ft_rdata;
17			output reg [`FIB_ENTRY_SZ-1:0] ft_wdata;
18	5	ghutchis	`output reg ft_rd_en, ft_wr_en;`
19	4	ghutchis	output reg [`FIB_ASZ-1:0] ft_addr;
20
21			output reg [`NUM_PORTS-1:0] lout_data;
22			`output reg lout_srdy;`
23			`input lout_drdy;`
24	5	ghutchis	output [`NUM_PORTS-1:0] lout_dst_vld;
25	4	ghutchis
26			wire [`FIB_ASZ-1:0] hf_out;
27			`reg [47:0] hf_in;`
28
29			wire [`NUM_PORTS-1:0] source_port_mask;
30
31			reg [`FIB_ASZ-1:0] init_ctr, nxt_init_ctr;
32			`reg [4:0] state, nxt_state;`
33
34			assign source_port_mask = 1 << lpp_data[`PAR_SRCPORT];
35
36			basic_hashfunc #(48, `FIB_ENTRIES) hashfunc
37			`(`
38			`// Outputs`
39			`.hf_out (hf_out),`
40			`// Inputs`
41			`.hf_in (hf_in));`
42
43			`localparam s_idle = 0, s_da_lookup = 1, s_sa_lookup = 2,`
44			`s_init0 = 3, s_init1 = 4;`
45			`localparam ns_idle = 1, ns_da_lookup = 2, ns_sa_lookup = 4,`
46			`ns_init0 = 8, ns_init1 = 16;`
47	5	ghutchis
48			`// send all results back to their originating port`
49			`assign lout_dst_vld = source_port_mask;`
50	9	ghutchis
51			`reg amux;`
52
53			`always @*`
54			`begin`
55			`case (amux)`
56
57			`1 : ft_addr = init_ctr;`
58			`endcase // case (amux)`
59			`end`
60	4	ghutchis
61			`always @*`
62			`begin`
63			`hf_in = 0;`
64			`nxt_state = state;`
65	5	ghutchis	`ft_rd_en = 0;`
66			`ft_wr_en = 0;`
67	9	ghutchis	`amux = 0;`
68	4	ghutchis	`lout_data = 0;`
69			`lout_srdy = 0;`
70			`lpp_drdy = 0;`
71			`nxt_init_ctr = init_ctr;`
72
73			`case (1'b1)`
74			`state[s_idle] :`
75			`begin`
76			`// DA lookup`
77			if (lpp_data[`PAR_MACDA] & `MULTICAST)
78			`begin`
79			`// flood the packet, don't bother to do DA lookup`
80			`lout_data = ~source_port_mask;`
81			`lout_srdy = 1;`
82			`if (lout_drdy)`
83			`nxt_state = ns_sa_lookup;`
84			`end`
85			`else if (lpp_srdy)`
86			`begin`
87			hf_in = lpp_data[`PAR_MACDA];
88	5	ghutchis	`ft_rd_en = 1;`
89	4	ghutchis	`nxt_state = ns_da_lookup;`
90			`end`
91			`end`
92
93			`// results from DA lookup are available this`
94			`// state. Make forwarding decision at this`
95			`// point.`
96			`state[s_da_lookup] :`
97			`begin`
98			`// no match, flood packet`
99			if (ft_rdata[`FIB_AGE] == 0)
100			`begin`
101			`lout_data = ~source_port_mask;`
102			`end`
103			`else`
104			`begin`
105	13	ghutchis	lout_data = (1 << ft_rdata[`FIB_PORT]) & ~source_port_mask;
106	4	ghutchis	`end`
107
108			`lout_srdy = 1;`
109			`if (lout_drdy)`
110			`nxt_state = ns_sa_lookup;`
111			`end // case: state[s_da_lookup]`
112
113			`// blind write out MACSA to FIB table`
114			`// will bump out current occupant and update`
115			`state[s_sa_lookup] :`
116			`begin`
117	5	ghutchis	`ft_wr_en = 1;`
118	4	ghutchis	hf_in = lpp_data[`PAR_MACSA];
119			ft_wdata[`FIB_MACADDR] = lpp_data[`PAR_MACSA];
120			ft_wdata[`FIB_AGE] = `FIB_MAX_AGE;
121			ft_wdata[`FIB_PORT] = lpp_data[`PAR_SRCPORT];
122			`nxt_state = ns_idle;`
123			`lpp_drdy = 1;`
124			`end`
125
126			`state[s_init0] :`
127			`begin`
128			`nxt_init_ctr = 0;`
129			`nxt_state = ns_init1;`
130			`end`
131
132			`state[s_init1] :`
133			`begin`
134			`nxt_init_ctr = init_ctr + 1;`
135	5	ghutchis	`ft_wr_en = 1;`
136	9	ghutchis	`amux = 1;`
137	4	ghutchis	`ft_wdata = 0;`
138	9	ghutchis	if (init_ctr == (`FIB_ENTRIES-1))
139	4	ghutchis	`nxt_state = ns_idle;`
140			`end`
141
142			`default :`
143			`nxt_state = ns_idle;`
144			`endcase // case (1'b1)`
145			`end // always @ *`
146
147			`always @(posedge clk)`
148			`begin`
149			`if (reset)`
150			`begin`
151			`init_ctr <= #1 0;`
152			`state <= #1 ns_init0;`
153			`end`
154			`else`
155			`begin`
156			`init_ctr <= #1 nxt_init_ctr;`
157			`state <= #1 nxt_state;`
158			`end`
159			`end`
160
161			`endmodule // fib_lookup_fsm`

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[/] [srdydrdy_lib/] [trunk/] [examples/] [bridge/] [rtl/] [fib_lookup_fsm.v] - Blame information for rev 13