packet_router: connected and created CPU read from interface (slow path in place)

1 files changed, 153 insertions, 47 deletions

diff --git a/usrp2/fifo/packet_router.v b/usrp2/fifo/packet_router.v
index 53cf1bcce..6a7826387 100644
--- a/usrp2/fifo/packet_router.v
+++ b/usrp2/fifo/packet_router.v
@@ -31,90 +31,196 @@ module packet_router
         output [35:0] eth_out_data, output eth_out_valid, input eth_out_ready
     );
 
+    assign wb_err_o = 1'b0;  // Unused for now
+    assign wb_rty_o = 1'b0;  // Unused for now
+    always @(posedge wb_clk_i)
+        wb_ack_o <= wb_stb_i & ~wb_ack_o;
+
+    ////////////////////////////////////////////////////////////////////
+    // CPU interface to this packet router
+    ////////////////////////////////////////////////////////////////////
+    wire [35:0] cpu_inp_data;
+    wire        cpu_inp_valid;
+    wire        cpu_inp_ready;
+    wire [35:0] cpu_out_data;
+    wire        cpu_out_valid;
+    wire        cpu_out_ready;
+
     //which buffer: 0 = CPU read buffer, 1 = CPU write buffer
     wire which_buf = wb_adr_i[BUF_SIZE+2];
 
     ////////////////////////////////////////////////////////////////////
-    // status and controls
+    // status and control handshakes
     ////////////////////////////////////////////////////////////////////
-    wire eth_to_cpu_flag_ack = control[0];
+    wire cpu_inp_hs_ctrl = control[0];
+    wire cpu_out_hs_ctrl = control[1];
+    wire [BUF_SIZE-1:0] cpu_out_line_count = control[BUF_SIZE-1+16:0+16];
+
+    wire cpu_inp_hs_stat;
+    assign status[0] = cpu_inp_hs_stat;
+
+    wire [BUF_SIZE-1:0] cpu_inp_line_count;
+    assign status[BUF_SIZE-1+16:0+16] = cpu_inp_line_count;
 
-    wire eth_to_cpu_flag_rdy;
-    assign status[0] = eth_to_cpu_flag_rdy;
+    wire cpu_out_hs_stat;
+    assign status[1] = cpu_out_hs_stat;
 
     ////////////////////////////////////////////////////////////////////
     // Ethernet input control
     ////////////////////////////////////////////////////////////////////
+    //TODO: just connect eth input to cpu input for now
+    assign cpu_inp_data = eth_inp_data;
+    assign cpu_inp_valid = eth_inp_valid;
+    assign eth_inp_ready = cpu_inp_ready;
 
-    localparam ETH_TO_CPU_STATE_WAIT_SOF = 0;
-    localparam ETH_TO_CPU_STATE_WAIT_EOF = 1;
-    localparam ETH_TO_CPU_STATE_WAIT_ACK_HI = 2;
-    localparam ETH_TO_CPU_STATE_WAIT_ACK_LO = 3;
+    ////////////////////////////////////////////////////////////////////
+    // Ethernet output control
+    ////////////////////////////////////////////////////////////////////
+    //TODO: just connect eth output to cpu output for now
+    assign eth_out_data = cpu_out_data;
+    assign eth_out_valid = cpu_out_valid;
+    assign cpu_out_ready = eth_out_ready;
 
-    reg [1:0] eth_to_cpu_state;
-    reg [BUF_SIZE-1:0] eth_to_cpu_addr;
-    wire [BUF_SIZE-1:0] eth_to_cpu_addr_next = eth_to_cpu_addr + 1'b1;
+    ////////////////////////////////////////////////////////////////////
+    // Interface CPU input interface to memory mapped wishbone
+    ////////////////////////////////////////////////////////////////////
+    localparam CPU_INP_STATE_WAIT_SOF = 0;
+    localparam CPU_INP_STATE_WAIT_EOF = 1;
+    localparam CPU_INP_STATE_WAIT_CTRL_HI = 2;
+    localparam CPU_INP_STATE_WAIT_CTRL_LO = 3;
+
+    reg [1:0] cpu_inp_state;
+    reg [BUF_SIZE-1:0] cpu_inp_addr;
+    assign cpu_inp_line_count = cpu_inp_addr;
+    wire [BUF_SIZE-1:0] cpu_inp_addr_next = cpu_inp_addr + 1'b1;
     
-    wire eth_to_cpu_reading_input = (
-        eth_to_cpu_state == ETH_TO_CPU_STATE_WAIT_SOF ||
-        eth_to_cpu_state == ETH_TO_CPU_STATE_WAIT_EOF
+    wire cpu_inp_reading = (
+        cpu_inp_state == CPU_INP_STATE_WAIT_SOF ||
+        cpu_inp_state == CPU_INP_STATE_WAIT_EOF
     )? 1'b1 : 1'b0;
 
-    wire eth_to_cpu_we = eth_to_cpu_reading_input;
-    assign eth_inp_ready = eth_to_cpu_reading_input;
-    assign eth_to_cpu_flag_rdy = (eth_to_cpu_state == ETH_TO_CPU_STATE_WAIT_ACK_HI)? 1'b1 : 1'b0;
-
-    assign wb_err_o = 1'b0;  // Unused for now
-    assign wb_rty_o = 1'b0;  // Unused for now
-    always @(posedge wb_clk_i)
-        wb_ack_o <= wb_stb_i & ~wb_ack_o;
+    wire cpu_inp_we = cpu_inp_reading;
+    assign cpu_inp_ready = cpu_inp_reading;
+    assign cpu_inp_hs_stat = (cpu_inp_state == CPU_INP_STATE_WAIT_CTRL_HI)? 1'b1 : 1'b0;
 
-    RAMB16_S36_S36 eth_to_cpu_buff(
-        //port A = wishbone memory mapped address space
-        .DOA(wb_dat_o),.ADDRA(wb_adr_i[BUF_SIZE+1:2]),.CLKA(wb_clk_i),.DIA(wb_dat_i),.DIPA(4'h0),
+    RAMB16_S36_S36 cpu_inp_buff(
+        //port A = wishbone memory mapped address space (output only)
+        .DOA(wb_dat_o),.ADDRA(wb_adr_i[BUF_SIZE+1:2]),.CLKA(wb_clk_i),.DIA(36'b0),.DIPA(4'h0),
         .ENA(wb_stb_i & (which_buf == 1'b0)),.SSRA(0),.WEA(wb_we_i),
-        //port B = input from ethernet packets
-        .DOB(),.ADDRB(eth_to_cpu_addr),.CLKB(stream_clk),.DIB(eth_inp_data),.DIPB(4'h0),
-        .ENB(eth_to_cpu_we),.SSRB(0),.WEB(eth_to_cpu_we)
+        //port B = packet router interface to CPU (input only)
+        .DOB(),.ADDRB(cpu_inp_addr),.CLKB(stream_clk),.DIB(cpu_inp_data),.DIPB(4'h0),
+        .ENB(cpu_inp_we),.SSRB(0),.WEB(cpu_inp_we)
     );
 
     always @(posedge stream_clk)
     if(stream_rst) begin
-        eth_to_cpu_state <= ETH_TO_CPU_STATE_WAIT_SOF;
-        eth_to_cpu_addr <= 0;
+        cpu_inp_state <= CPU_INP_STATE_WAIT_SOF;
+        cpu_inp_addr <= 0;
     end
     else begin
-        case(eth_to_cpu_state)
-        ETH_TO_CPU_STATE_WAIT_SOF: begin
-            if (eth_inp_ready & eth_inp_valid & (eth_inp_data[32] == 1'b1)) begin
-                eth_to_cpu_state <= ETH_TO_CPU_STATE_WAIT_EOF;
-                eth_to_cpu_addr <= eth_to_cpu_addr_next;
+        case(cpu_inp_state)
+        CPU_INP_STATE_WAIT_SOF: begin
+            if (cpu_inp_ready & cpu_inp_valid & (cpu_inp_data[32] == 1'b1)) begin
+                cpu_inp_state <= CPU_INP_STATE_WAIT_EOF;
+                cpu_inp_addr <= cpu_inp_addr_next;
             end
         end
 
-        ETH_TO_CPU_STATE_WAIT_EOF: begin
-            if (eth_inp_ready & eth_inp_valid & (eth_inp_data[33] == 1'b1)) begin
-                eth_to_cpu_state <= ETH_TO_CPU_STATE_WAIT_ACK_HI;
+        CPU_INP_STATE_WAIT_EOF: begin
+            if (cpu_inp_ready & cpu_inp_valid & (cpu_inp_data[33] == 1'b1)) begin
+                cpu_inp_state <= CPU_INP_STATE_WAIT_CTRL_HI;
             end
-            if (eth_inp_ready & eth_inp_valid) begin
-                eth_to_cpu_addr <= eth_to_cpu_addr_next;
+            if (cpu_inp_ready & cpu_inp_valid) begin
+                cpu_inp_addr <= cpu_inp_addr_next;
             end
         end
 
-        ETH_TO_CPU_STATE_WAIT_ACK_HI: begin
-            if (eth_to_cpu_flag_ack == 1'b1) begin
-                eth_to_cpu_state <= ETH_TO_CPU_STATE_WAIT_ACK_LO;
+        CPU_INP_STATE_WAIT_CTRL_HI: begin
+            if (cpu_inp_hs_ctrl == 1'b1) begin
+                cpu_inp_state <= CPU_INP_STATE_WAIT_CTRL_LO;
             end
         end
 
-        ETH_TO_CPU_STATE_WAIT_ACK_LO: begin
-            if (eth_to_cpu_flag_ack == 0'b1) begin
-                eth_to_cpu_state <= ETH_TO_CPU_STATE_WAIT_SOF;
+        CPU_INP_STATE_WAIT_CTRL_LO: begin
+            if (cpu_inp_hs_ctrl == 1'b0) begin
+                cpu_inp_state <= CPU_INP_STATE_WAIT_SOF;
             end
+            cpu_inp_addr <= 0; //reset the address counter
         end
 
-        endcase //eth_to_cpu_state
+        endcase //cpu_inp_state
     end
 
+    ////////////////////////////////////////////////////////////////////
+    // Interface CPU output interface to memory mapped wishbone
+    ////////////////////////////////////////////////////////////////////
+    localparam CPU_OUT_STATE_WAIT_CTRL_HI = 0;
+    localparam CPU_OUT_STATE_WAIT_CTRL_LO = 1;
+    localparam CPU_OUT_STATE_UNLOAD = 2;
+
+    reg [1:0] cpu_out_state;
+    reg [BUF_SIZE-1:0] cpu_out_addr;
+    wire [BUF_SIZE-1:0] cpu_out_addr_next = cpu_out_addr + 1'b1;
+
+    reg [BUF_SIZE-1:0] cpu_out_line_count_reg;
+
+    reg cpu_out_flag_sof;
+    reg cpu_out_flag_eof;
+    assign cpu_out_data[35:32] = {2'b0, cpu_out_flag_eof, cpu_out_flag_sof};
+
+    assign cpu_out_valid = (cpu_out_state == CPU_OUT_STATE_UNLOAD)? 1'b1 : 1'b0;
+    assign cpu_out_hs_stat = (cpu_out_state == CPU_OUT_STATE_WAIT_CTRL_HI)? 1'b1 : 1'b0;
+
+    RAMB16_S36_S36 cpu_out_buff(
+        //port A = wishbone memory mapped address space (input only)
+        .DOA(),.ADDRA(wb_adr_i[BUF_SIZE+1:2]),.CLKA(wb_clk_i),.DIA(wb_dat_i),.DIPA(4'h0),
+        .ENA(wb_stb_i & (which_buf == 1'b1)),.SSRA(0),.WEA(wb_we_i),
+        //port B = packet router interface from CPU (output only)
+        .DOB(cpu_out_data[31:0]),.ADDRB(cpu_out_addr),.CLKB(stream_clk),.DIB(36'b0),.DIPB(4'h0),
+        .ENB(1'b1),.SSRB(0),.WEB(1'b0)
+    );
+
+    always @(posedge stream_clk)
+    if(stream_rst) begin
+        cpu_out_state <= CPU_OUT_STATE_WAIT_CTRL_HI;
+        cpu_out_addr <= 0;
+    end
+    else begin
+        case(cpu_out_state)
+        CPU_OUT_STATE_WAIT_CTRL_HI: begin
+            if (cpu_out_hs_ctrl == 1'b1) begin
+                cpu_out_state <= CPU_OUT_STATE_WAIT_CTRL_LO;
+            end
+            cpu_out_line_count_reg <= cpu_out_line_count;
+            cpu_out_addr <= 0; //reset the address counter
+        end
+
+        CPU_OUT_STATE_WAIT_CTRL_LO: begin
+            if (cpu_out_hs_ctrl == 1'b0) begin
+                cpu_out_state <= CPU_OUT_STATE_UNLOAD;
+                cpu_out_addr <= cpu_out_addr_next;
+            end
+            cpu_out_flag_sof <= 1'b1;
+            cpu_out_flag_eof <= 1'b0;
+        end
+
+        CPU_OUT_STATE_UNLOAD: begin
+            if (cpu_out_ready & cpu_out_valid) begin
+                cpu_out_addr <= cpu_out_addr_next;
+                cpu_out_flag_sof <= 1'b0;
+                if (cpu_out_addr == cpu_out_line_count_reg) begin
+                    cpu_out_flag_eof <= 1'b1;
+                end
+                else begin
+                    cpu_out_flag_eof <= 1'b0;
+                end
+                if (cpu_out_flag_eof) begin
+                    cpu_out_state <= CPU_OUT_STATE_WAIT_CTRL_HI;
+                end
+            end
+        end
+
+        endcase //cpu_out_state
+    end
 
 endmodule // packet_router