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[/] [srdydrdy_lib/] [trunk/] [examples/] [bridge/] [rtl/] [fib_lookup_fsm.v] - Blame information for rev 4

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

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[/] [srdydrdy_lib/] [trunk/] [examples/] [bridge/] [rtl/] [fib_lookup_fsm.v] - Blame information for rev 4