FPGA/corundum
1
0
Fork 0
mirror of https://github.com/corundum/corundum.git synced 2025-01-16 08:12:53 +08:00
Code Issues Projects Releases Wiki Activity

Add COBS encoder and decoder modules and testbench

Browse Source
This commit is contained in:
Alex Forencich 2016-08-21 20:03:54 -07:00
parent e6d78b7ca7
commit 24f7aee8b2
8 changed files with 2324 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

328
rtl/axis_cobs_decode.v Normal file
View File

@ -0,0 +1,328 @@
/*
Copyright (c) 2016 Alex Forencich
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
// Language: Verilog 2001
`timescale 1ns / 1ps
/*
* AXI4-Stream consistent overhead byte stuffing (COBS) decoder
*/
module axis_cobs_decode
(
input wire clk,
input wire rst,
/*
* AXI input
*/
input wire [7:0] input_axis_tdata,
input wire input_axis_tvalid,
output wire input_axis_tready,
input wire input_axis_tlast,
input wire input_axis_tuser,
/*
* AXI output
*/
output wire [7:0] output_axis_tdata,
output wire output_axis_tvalid,
input wire output_axis_tready,
output wire output_axis_tlast,
output wire output_axis_tuser
);
// state register
localparam [1:0]
STATE_IDLE = 2'd0,
STATE_SEGMENT = 2'd1,
STATE_NEXT_SEGMENT = 2'd2;
reg [1:0] state_reg = STATE_IDLE, state_next;
reg [7:0] count_reg = 8'd0, count_next;
reg suppress_zero_reg = 1'b0, suppress_zero_next;
reg [7:0] temp_tdata_reg = 8'd0, temp_tdata_next;
reg temp_tvalid_reg = 1'b0, temp_tvalid_next;
// internal datapath
reg [7:0] output_axis_tdata_int;
reg output_axis_tvalid_int;
reg output_axis_tready_int_reg = 1'b0;
reg output_axis_tlast_int;
reg output_axis_tuser_int;
wire output_axis_tready_int_early;
reg input_axis_tready_reg = 1'b0, input_axis_tready_next;
assign input_axis_tready = input_axis_tready_reg;
always @* begin
state_next = STATE_IDLE;
count_next = count_reg;
suppress_zero_next = suppress_zero_reg;
temp_tdata_next = temp_tdata_reg;
temp_tvalid_next = temp_tvalid_reg;
output_axis_tdata_int = 8'd0;
output_axis_tvalid_int = 1'b0;
output_axis_tlast_int = 1'b0;
output_axis_tuser_int = 1'b0;
input_axis_tready_next = 1'b0;
case (state_reg)
STATE_IDLE: begin
// idle state
input_axis_tready_next = output_axis_tready_int_early | ~temp_tvalid_reg;
// output final word
output_axis_tdata_int = temp_tdata_reg;
output_axis_tvalid_int = temp_tvalid_reg;
output_axis_tlast_int = temp_tvalid_reg;
temp_tvalid_next = temp_tvalid_reg & ~output_axis_tready_int_reg;
if (input_axis_tready & input_axis_tvalid) begin
// valid input data
// skip any leading zeros
if (input_axis_tdata != 8'd0) begin
// store count value and zero suppress
count_next = input_axis_tdata-1;
suppress_zero_next = (input_axis_tdata == 8'd255);
input_axis_tready_next = output_axis_tready_int_early;
if (input_axis_tdata == 8'd1) begin
// next byte will be count value
state_next = STATE_NEXT_SEGMENT;
end else begin
// next byte will be data
state_next = STATE_SEGMENT;
end
end else begin
state_next = STATE_IDLE;
end
end else begin
state_next = STATE_IDLE;
end
end
STATE_SEGMENT: begin
// receive segment
input_axis_tready_next = output_axis_tready_int_early;
if (input_axis_tready & input_axis_tvalid) begin
// valid input data
// store in temp register
temp_tdata_next = input_axis_tdata;
temp_tvalid_next = 1'b1;
// move temp to output
output_axis_tdata_int = temp_tdata_reg;
output_axis_tvalid_int = temp_tvalid_reg;
// decrement count
count_next = count_reg - 1;
if (input_axis_tdata == 8'd0) begin
// got a zero byte in a frame - mark it as an error and re-sync
temp_tvalid_next = 1'b0;
output_axis_tvalid_int = 1'b1;
output_axis_tuser_int = 1'b1;
output_axis_tlast_int = 1'b1;
input_axis_tready_next = 1'b1;
state_next = STATE_IDLE;
end else if (input_axis_tlast) begin
// end of frame
if (count_reg == 8'd1 && ~input_axis_tuser) begin
// end of frame indication at correct time, go to idle to output final byte
state_next = STATE_IDLE;
end else begin
// end of frame indication at invalid time or tuser assert, so mark as an error and re-sync
temp_tvalid_next = 1'b0;
output_axis_tvalid_int = 1'b1;
output_axis_tuser_int = 1'b1;
output_axis_tlast_int = 1'b1;
input_axis_tready_next = 1'b1;
state_next = STATE_IDLE;
end
end else if (count_reg == 8'd1) begin
// next byte will be count value
state_next = STATE_NEXT_SEGMENT;
end else begin
// next byte will be data
state_next = STATE_SEGMENT;
end
end else begin
state_next = STATE_SEGMENT;
end
end
STATE_NEXT_SEGMENT: begin
// next segment
input_axis_tready_next = output_axis_tready_int_early;
if (input_axis_tready & input_axis_tvalid) begin
// valid input data
// store zero in temp if not suppressed
temp_tdata_next = 8'd0;
temp_tvalid_next = ~suppress_zero_reg;
// move temp to output
output_axis_tdata_int = temp_tdata_reg;
output_axis_tvalid_int = temp_tvalid_reg;
if (input_axis_tdata == 8'd0) begin
// got a zero byte delineating the end of the frame, so mark as such and re-sync
temp_tvalid_next = 1'b0;
output_axis_tuser_int = input_axis_tuser;
output_axis_tlast_int = 1'b1;
input_axis_tready_next = 1'b1;
state_next = STATE_IDLE;
end else if (input_axis_tlast) begin
if (input_axis_tdata == 8'd1 && ~input_axis_tuser) begin
// end of frame indication at correct time, go to idle to output final byte
state_next = STATE_IDLE;
end else begin
// end of frame indication at invalid time or tuser assert, so mark as an error and re-sync
temp_tvalid_next = 1'b0;
output_axis_tvalid_int = 1'b1;
output_axis_tuser_int = 1'b1;
output_axis_tlast_int = 1'b1;
input_axis_tready_next = 1'b1;
state_next = STATE_IDLE;
end
end else begin
// otherwise, store count value and zero suppress
count_next = input_axis_tdata-1;
suppress_zero_next = (input_axis_tdata == 8'd255);
input_axis_tready_next = output_axis_tready_int_early;
if (input_axis_tdata == 8'd1) begin
// next byte will be count value
state_next = STATE_NEXT_SEGMENT;
end else begin
// next byte will be data
state_next = STATE_SEGMENT;
end
end
end else begin
state_next = STATE_NEXT_SEGMENT;
end
end
endcase
end
always @(posedge clk) begin
if (rst) begin
state_reg <= STATE_IDLE;
temp_tvalid_reg <= 1'b0;
input_axis_tready_reg <= 1'b0;
end else begin
state_reg <= state_next;
temp_tvalid_reg <= temp_tvalid_next;
input_axis_tready_reg <= input_axis_tready_next;
end
temp_tdata_reg <= temp_tdata_next;
count_reg <= count_next;
suppress_zero_reg <= suppress_zero_next;
end
// output datapath logic
reg [7:0] output_axis_tdata_reg = 8'd0;
reg output_axis_tvalid_reg = 1'b0, output_axis_tvalid_next;
reg output_axis_tlast_reg = 1'b0;
reg output_axis_tuser_reg = 1'b0;
reg [7:0] temp_axis_tdata_reg = 8'd0;
reg temp_axis_tvalid_reg = 1'b0, temp_axis_tvalid_next;
reg temp_axis_tlast_reg = 1'b0;
reg temp_axis_tuser_reg = 1'b0;
// datapath control
reg store_axis_int_to_output;
reg store_axis_int_to_temp;
reg store_axis_temp_to_output;
assign output_axis_tdata = output_axis_tdata_reg;
assign output_axis_tvalid = output_axis_tvalid_reg;
assign output_axis_tlast = output_axis_tlast_reg;
assign output_axis_tuser = output_axis_tuser_reg;
// enable ready input next cycle if output is ready or the temp reg will not be filled on the next cycle (output reg empty or no input)
assign output_axis_tready_int_early = output_axis_tready | (~temp_axis_tvalid_reg & (~output_axis_tvalid_reg | ~output_axis_tvalid_int));
always @* begin
// transfer sink ready state to source
output_axis_tvalid_next = output_axis_tvalid_reg;
temp_axis_tvalid_next = temp_axis_tvalid_reg;
store_axis_int_to_output = 1'b0;
store_axis_int_to_temp = 1'b0;
store_axis_temp_to_output = 1'b0;
if (output_axis_tready_int_reg) begin
// input is ready
if (output_axis_tready | ~output_axis_tvalid_reg) begin
// output is ready or currently not valid, transfer data to output
output_axis_tvalid_next = output_axis_tvalid_int;
store_axis_int_to_output = 1'b1;
end else begin
// output is not ready, store input in temp
temp_axis_tvalid_next = output_axis_tvalid_int;
store_axis_int_to_temp = 1'b1;
end
end else if (output_axis_tready) begin
// input is not ready, but output is ready
output_axis_tvalid_next = temp_axis_tvalid_reg;
temp_axis_tvalid_next = 1'b0;
store_axis_temp_to_output = 1'b1;
end
end
always @(posedge clk) begin
if (rst) begin
output_axis_tvalid_reg <= 1'b0;
output_axis_tready_int_reg <= 1'b0;
temp_axis_tvalid_reg <= 1'b0;
end else begin
output_axis_tvalid_reg <= output_axis_tvalid_next;
output_axis_tready_int_reg <= output_axis_tready_int_early;
temp_axis_tvalid_reg <= temp_axis_tvalid_next;
end
// datapath
if (store_axis_int_to_output) begin
output_axis_tdata_reg <= output_axis_tdata_int;
output_axis_tlast_reg <= output_axis_tlast_int;
output_axis_tuser_reg <= output_axis_tuser_int;
end else if (store_axis_temp_to_output) begin
output_axis_tdata_reg <= temp_axis_tdata_reg;
output_axis_tlast_reg <= temp_axis_tlast_reg;
output_axis_tuser_reg <= temp_axis_tuser_reg;
end
if (store_axis_int_to_temp) begin
temp_axis_tdata_reg <= output_axis_tdata_int;
temp_axis_tlast_reg <= output_axis_tlast_int;
temp_axis_tuser_reg <= output_axis_tuser_int;
end
end
endmodule

473
rtl/axis_cobs_encode.v Normal file
View File

@ -0,0 +1,473 @@
/*
Copyright (c) 2016 Alex Forencich
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
// Language: Verilog 2001
`timescale 1ns / 1ps
/*
* AXI4-Stream consistent overhead byte stuffing (COBS) encoder
*/
module axis_cobs_encode #
(
// append zero for in band framing
parameter APPEND_ZERO = 1
)
(
input wire clk,
input wire rst,
/*
* AXI input
*/
input wire [7:0] input_axis_tdata,
input wire input_axis_tvalid,
output wire input_axis_tready,
input wire input_axis_tlast,
input wire input_axis_tuser,
/*
* AXI output
*/
output wire [7:0] output_axis_tdata,
output wire output_axis_tvalid,
input wire output_axis_tready,
output wire output_axis_tlast,
output wire output_axis_tuser
);
// state register
localparam [1:0]
INPUT_STATE_IDLE = 2'd0,
INPUT_STATE_SEGMENT = 2'd1,
INPUT_STATE_FINAL_ZERO = 2'd2,
INPUT_STATE_APPEND_ZERO = 2'd3;
reg [1:0] input_state_reg = INPUT_STATE_IDLE, input_state_next;
localparam [0:0]
OUTPUT_STATE_IDLE = 1'd0,
OUTPUT_STATE_SEGMENT = 1'd1;
reg [0:0] output_state_reg = OUTPUT_STATE_IDLE, output_state_next;
reg [7:0] input_count_reg = 8'd0, input_count_next;
reg [7:0] output_count_reg = 8'd0, output_count_next;
reg fail_frame_reg = 1'b0, fail_frame_next;
// internal datapath
reg [7:0] output_axis_tdata_int;
reg output_axis_tvalid_int;
reg output_axis_tready_int_reg = 1'b0;
reg output_axis_tlast_int;
reg output_axis_tuser_int;
wire output_axis_tready_int_early;
reg input_axis_tready_mask;
assign input_axis_tready = code_fifo_in_tready & data_fifo_in_tready & input_axis_tready_mask;
reg [7:0] code_fifo_in_tdata;
reg code_fifo_in_tvalid;
reg code_fifo_in_tlast;
reg code_fifo_in_tuser;
wire code_fifo_in_tready;
wire [7:0] code_fifo_out_tdata;
wire code_fifo_out_tvalid;
wire code_fifo_out_tlast;
wire code_fifo_out_tuser;
reg code_fifo_out_tready;
axis_fifo #(
.ADDR_WIDTH(8),
.DATA_WIDTH(8)
)
code_fifo_inst (
.clk(clk),
.rst(rst),
// AXI input
.input_axis_tdata(code_fifo_in_tdata),
.input_axis_tvalid(code_fifo_in_tvalid),
.input_axis_tready(code_fifo_in_tready),
.input_axis_tlast(code_fifo_in_tlast),
.input_axis_tuser(code_fifo_in_tuser),
// AXI output
.output_axis_tdata(code_fifo_out_tdata),
.output_axis_tvalid(code_fifo_out_tvalid),
.output_axis_tready(code_fifo_out_tready),
.output_axis_tlast(code_fifo_out_tlast),
.output_axis_tuser(code_fifo_out_tuser)
);
reg [7:0] data_fifo_in_tdata;
reg data_fifo_in_tvalid;
reg data_fifo_in_tlast;
wire data_fifo_in_tready;
wire [7:0] data_fifo_out_tdata;
wire data_fifo_out_tvalid;
wire data_fifo_out_tlast;
reg data_fifo_out_tready;
axis_fifo #(
.ADDR_WIDTH(8),
.DATA_WIDTH(8)
)
data_fifo_inst (
.clk(clk),
.rst(rst),
// AXI input
.input_axis_tdata(data_fifo_in_tdata),
.input_axis_tvalid(data_fifo_in_tvalid),
.input_axis_tready(data_fifo_in_tready),
.input_axis_tlast(data_fifo_in_tlast),
.input_axis_tuser(1'b0),
// AXI output
.output_axis_tdata(data_fifo_out_tdata),
.output_axis_tvalid(data_fifo_out_tvalid),
.output_axis_tready(data_fifo_out_tready),
.output_axis_tlast(data_fifo_out_tlast),
.output_axis_tuser()
);
always @* begin
input_state_next = INPUT_STATE_IDLE;
input_count_next = input_count_reg;
fail_frame_next = fail_frame_reg;
input_axis_tready_mask = 1'b0;
code_fifo_in_tdata = 8'd0;
code_fifo_in_tvalid = 1'b0;
code_fifo_in_tlast = 1'b0;
code_fifo_in_tuser = 1'b0;
data_fifo_in_tdata = input_axis_tdata;
data_fifo_in_tvalid = 1'b0;
data_fifo_in_tlast = 1'b0;
case (input_state_reg)
INPUT_STATE_IDLE: begin
// idle state
input_axis_tready_mask = 1'b1;
fail_frame_next = 1'b0;
if (input_axis_tready & input_axis_tvalid) begin
// valid input data
if (input_axis_tdata == 8'd0 || (input_axis_tlast & input_axis_tuser)) begin
// got a zero or propagated error, so store a zero code
code_fifo_in_tdata = 8'd1;
code_fifo_in_tvalid = 1'b1;
if (input_axis_tlast) begin
// last byte, so close out the frame
fail_frame_next = input_axis_tuser;
input_state_next = INPUT_STATE_FINAL_ZERO;
end else begin
// return to idle to await next segment
input_state_next = INPUT_STATE_IDLE;
end
end else begin
// got something other than a zero, so store it and init the segment counter
input_count_next = 8'd2;
data_fifo_in_tdata = input_axis_tdata;
data_fifo_in_tvalid = 1'b1;
if (input_axis_tlast) begin
// last byte, so store the code and close out the frame
code_fifo_in_tdata = 8'd2;
code_fifo_in_tvalid = 1'b1;
if (APPEND_ZERO) begin
// zero frame mode, need to add a zero code to end the frame
input_state_next = INPUT_STATE_APPEND_ZERO;
end else begin
// normal frame mode, close out the frame
data_fifo_in_tlast = 1'b1;
input_state_next = INPUT_STATE_IDLE;
end
end else begin
// await more segment data
input_state_next = INPUT_STATE_SEGMENT;
end
end
end else begin
input_state_next = INPUT_STATE_IDLE;
end
end
INPUT_STATE_SEGMENT: begin
// encode segment
input_axis_tready_mask = 1'b1;
fail_frame_next = 1'b0;
if (input_axis_tready & input_axis_tvalid) begin
// valid input data
if (input_axis_tdata == 8'd0 || (input_axis_tlast & input_axis_tuser)) begin
// got a zero or propagated error, so store the code
code_fifo_in_tdata = input_count_reg;
code_fifo_in_tvalid = 1'b1;
if (input_axis_tlast) begin
// last byte, so close out the frame
fail_frame_next = input_axis_tuser;
input_state_next = INPUT_STATE_FINAL_ZERO;
end else begin
// return to idle to await next segment
input_state_next = INPUT_STATE_IDLE;
end
end else begin
// got something other than a zero, so store it and increment the segment counter
input_count_next = input_count_reg+1;
data_fifo_in_tdata = input_axis_tdata;
data_fifo_in_tvalid = 1'b1;
if (input_count_reg == 8'd254) begin
// 254 bytes in frame, so dump and reset counter
code_fifo_in_tdata = input_count_reg+1;
code_fifo_in_tvalid = 1'b1;
input_count_next = 8'd1;
end
if (input_axis_tlast) begin
// last byte, so store the code and close out the frame
code_fifo_in_tdata = input_count_reg+1;
code_fifo_in_tvalid = 1'b1;
if (APPEND_ZERO) begin
// zero frame mode, need to add a zero code to end the frame
input_state_next = INPUT_STATE_APPEND_ZERO;
end else begin
// normal frame mode, close out the frame
data_fifo_in_tlast = 1'b1;
input_state_next = INPUT_STATE_IDLE;
end
end else begin
// await more segment data
input_state_next = INPUT_STATE_SEGMENT;
end
end
end else begin
input_state_next = INPUT_STATE_SEGMENT;
end
end
INPUT_STATE_FINAL_ZERO: begin
// final zero code required
input_axis_tready_mask = 1'b0;
if (code_fifo_in_tready) begin
// push a zero code and close out frame
if (fail_frame_reg) begin
code_fifo_in_tdata = 8'd2;
code_fifo_in_tuser = 1'b1;
end else begin
code_fifo_in_tdata = 8'd1;
end
code_fifo_in_tvalid = 1'b1;
if (APPEND_ZERO) begin
// zero frame mode, need to add a zero code to end the frame
input_state_next = INPUT_STATE_APPEND_ZERO;
end else begin
// normal frame mode, close out the frame
code_fifo_in_tlast = 1'b1;
fail_frame_next = 1'b0;
input_state_next = INPUT_STATE_IDLE;
end
end else begin
input_state_next = INPUT_STATE_FINAL_ZERO;
end
end
INPUT_STATE_APPEND_ZERO: begin
// append zero for zero framing
input_axis_tready_mask = 1'b0;
if (code_fifo_in_tready) begin
// push frame termination code and close out frame
code_fifo_in_tdata = 8'd0;
code_fifo_in_tlast = 1'b1;
code_fifo_in_tuser = fail_frame_reg;
code_fifo_in_tvalid = 1'b1;
fail_frame_next = 1'b0;
input_state_next = INPUT_STATE_IDLE;
end else begin
input_state_next = INPUT_STATE_APPEND_ZERO;
end
end
endcase
end
always @* begin
output_state_next = OUTPUT_STATE_IDLE;
output_count_next = output_count_reg;
output_axis_tdata_int = 8'd0;
output_axis_tvalid_int = 1'b0;
output_axis_tlast_int = 1'b0;
output_axis_tuser_int = 1'b0;
code_fifo_out_tready = 1'b0;
data_fifo_out_tready = 1'b0;
case (output_state_reg)
OUTPUT_STATE_IDLE: begin
// idle state
if (output_axis_tready_int_reg & code_fifo_out_tvalid) begin
// transfer out code byte and load counter
output_axis_tdata_int = code_fifo_out_tdata;
output_axis_tlast_int = code_fifo_out_tlast;
output_axis_tuser_int = code_fifo_out_tuser & code_fifo_out_tlast;
output_count_next = code_fifo_out_tdata-1;
output_axis_tvalid_int = 1'b1;
code_fifo_out_tready = 1'b1;
if (code_fifo_out_tdata == 8'd0 || code_fifo_out_tdata == 8'd1 || code_fifo_out_tuser) begin
// frame termination and zero codes will be followed by codes
output_state_next = OUTPUT_STATE_IDLE;
end else begin
// transfer out data
output_state_next = OUTPUT_STATE_SEGMENT;
end
end else begin
output_state_next = OUTPUT_STATE_IDLE;
end
end
OUTPUT_STATE_SEGMENT: begin
// segment output
if (output_axis_tready_int_reg & data_fifo_out_tvalid) begin
// transfer out data byte and decrement counter
output_axis_tdata_int = data_fifo_out_tdata;
output_axis_tlast_int = data_fifo_out_tlast;
output_count_next = output_count_reg - 1;
output_axis_tvalid_int = 1'b1;
data_fifo_out_tready = 1'b1;
if (output_count_reg == 1'b1) begin
// done with segment, get a code byte next
output_state_next = OUTPUT_STATE_IDLE;
end else begin
// more data to transfer
output_state_next = OUTPUT_STATE_SEGMENT;
end
end else begin
output_state_next = OUTPUT_STATE_SEGMENT;
end
end
endcase
end
always @(posedge clk) begin
if (rst) begin
input_state_reg <= INPUT_STATE_IDLE;
output_state_reg <= OUTPUT_STATE_IDLE;
end else begin
input_state_reg <= input_state_next;
output_state_reg <= output_state_next;
end
input_count_reg <= input_count_next;
output_count_reg <= output_count_next;
fail_frame_reg <= fail_frame_next;
end
// output datapath logic
reg [7:0] output_axis_tdata_reg = 8'd0;
reg output_axis_tvalid_reg = 1'b0, output_axis_tvalid_next;
reg output_axis_tlast_reg = 1'b0;
reg output_axis_tuser_reg = 1'b0;
reg [7:0] temp_axis_tdata_reg = 8'd0;
reg temp_axis_tvalid_reg = 1'b0, temp_axis_tvalid_next;
reg temp_axis_tlast_reg = 1'b0;
reg temp_axis_tuser_reg = 1'b0;
// datapath control
reg store_axis_int_to_output;
reg store_axis_int_to_temp;
reg store_axis_temp_to_output;
assign output_axis_tdata = output_axis_tdata_reg;
assign output_axis_tvalid = output_axis_tvalid_reg;
assign output_axis_tlast = output_axis_tlast_reg;
assign output_axis_tuser = output_axis_tuser_reg;
// enable ready input next cycle if output is ready or the temp reg will not be filled on the next cycle (output reg empty or no input)
assign output_axis_tready_int_early = output_axis_tready | (~temp_axis_tvalid_reg & (~output_axis_tvalid_reg | ~output_axis_tvalid_int));
always @* begin
// transfer sink ready state to source
output_axis_tvalid_next = output_axis_tvalid_reg;
temp_axis_tvalid_next = temp_axis_tvalid_reg;
store_axis_int_to_output = 1'b0;
store_axis_int_to_temp = 1'b0;
store_axis_temp_to_output = 1'b0;
if (output_axis_tready_int_reg) begin
// input is ready
if (output_axis_tready | ~output_axis_tvalid_reg) begin
// output is ready or currently not valid, transfer data to output
output_axis_tvalid_next = output_axis_tvalid_int;
store_axis_int_to_output = 1'b1;
end else begin
// output is not ready, store input in temp
temp_axis_tvalid_next = output_axis_tvalid_int;
store_axis_int_to_temp = 1'b1;
end
end else if (output_axis_tready) begin
// input is not ready, but output is ready
output_axis_tvalid_next = temp_axis_tvalid_reg;
temp_axis_tvalid_next = 1'b0;
store_axis_temp_to_output = 1'b1;
end
end
always @(posedge clk) begin
if (rst) begin
output_axis_tvalid_reg <= 1'b0;
output_axis_tready_int_reg <= 1'b0;
temp_axis_tvalid_reg <= 1'b0;
end else begin
output_axis_tvalid_reg <= output_axis_tvalid_next;
output_axis_tready_int_reg <= output_axis_tready_int_early;
temp_axis_tvalid_reg <= temp_axis_tvalid_next;
end
// datapath
if (store_axis_int_to_output) begin
output_axis_tdata_reg <= output_axis_tdata_int;
output_axis_tlast_reg <= output_axis_tlast_int;
output_axis_tuser_reg <= output_axis_tuser_int;
end else if (store_axis_temp_to_output) begin
output_axis_tdata_reg <= temp_axis_tdata_reg;
output_axis_tlast_reg <= temp_axis_tlast_reg;
output_axis_tuser_reg <= temp_axis_tuser_reg;
end
if (store_axis_int_to_temp) begin
temp_axis_tdata_reg <= output_axis_tdata_int;
temp_axis_tlast_reg <= output_axis_tlast_int;
temp_axis_tuser_reg <= output_axis_tuser_int;
end
end
endmodule

482
tb/test_axis_cobs_decode.py Executable file
View File

@ -0,0 +1,482 @@
#!/usr/bin/env python
"""
Copyright (c) 2016 Alex Forencich
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
"""
from myhdl import *
import os
try:
from queue import Queue
except ImportError:
from Queue import Queue
import axis_ep
module = 'axis_cobs_decode'
testbench = 'test_axis_cobs_decode'
srcs = []
srcs.append("../rtl/%s.v" % module)
srcs.append("%s.v" % testbench)
src = ' '.join(srcs)
build_cmd = "iverilog -o %s.vvp %s" % (testbench, src)
def dut_axis_cobs_decode(clk,
rst,
current_test,
input_axis_tdata,
input_axis_tvalid,
input_axis_tready,
input_axis_tlast,
input_axis_tuser,
output_axis_tdata,
output_axis_tvalid,
output_axis_tready,
output_axis_tlast,
output_axis_tuser):
if os.system(build_cmd):
raise Exception("Error running build command")
return Cosimulation("vvp -m myhdl %s.vvp -lxt2" % testbench,
clk=clk,
rst=rst,
current_test=current_test,
input_axis_tdata=input_axis_tdata,
input_axis_tvalid=input_axis_tvalid,
input_axis_tready=input_axis_tready,
input_axis_tlast=input_axis_tlast,
input_axis_tuser=input_axis_tuser,
output_axis_tdata=output_axis_tdata,
output_axis_tvalid=output_axis_tvalid,
output_axis_tready=output_axis_tready,
output_axis_tlast=output_axis_tlast,
output_axis_tuser=output_axis_tuser)
def cobs_encode(block):
block = bytearray(block)
enc = bytearray()
seg = bytearray()
code = 1
new_data = True
for b in block:
if b == 0:
enc.append(code)
enc.extend(seg)
code = 1
seg = bytearray()
new_data = True
else:
code += 1
seg.append(b)
new_data = True
if code == 255:
enc.append(code)
enc.extend(seg)
code = 1
seg = bytearray()
new_data = False
if new_data:
enc.append(code)
enc.extend(seg)
return bytes(enc)
def cobs_decode(block):
block = bytearray(block)
dec = bytearray()
it = iter(bytearray(block))
code = 0
i = 0
if 0 in block:
return None
while i < len(block):
code = block[i]
i += 1
if i+code-1 > len(block):
return None
for k in range(code-1):
dec.append(block[i])
i += 1
if code < 255 and i < len(block):
dec.append(0)
return bytes(dec)
def prbs31(state = 0x7fffffff):
while True:
for i in range(8):
if bool(state & 0x08000000) ^ bool(state & 0x40000000):
state = ((state & 0x3fffffff) << 1) | 1
else:
state = (state & 0x3fffffff) << 1
yield state & 0xff
def bench():
# Parameters
# Inputs
clk = Signal(bool(0))
rst = Signal(bool(0))
current_test = Signal(intbv(0)[8:])
input_axis_tdata = Signal(intbv(0)[8:])
input_axis_tvalid = Signal(bool(0))
input_axis_tlast = Signal(bool(0))
input_axis_tuser = Signal(bool(0))
output_axis_tready = Signal(bool(0))
# Outputs
input_axis_tready = Signal(bool(0))
output_axis_tdata = Signal(intbv(0)[8:])
output_axis_tvalid = Signal(bool(0))
output_axis_tlast = Signal(bool(0))
output_axis_tuser = Signal(bool(0))
# sources and sinks
source_queue = Queue()
source_pause = Signal(bool(0))
sink_queue = Queue()
sink_pause = Signal(bool(0))
source = axis_ep.AXIStreamSource(clk,
rst,
tdata=input_axis_tdata,
tvalid=input_axis_tvalid,
tready=input_axis_tready,
tlast=input_axis_tlast,
tuser=input_axis_tuser,
fifo=source_queue,
pause=source_pause,
name='source')
sink = axis_ep.AXIStreamSink(clk,
rst,
tdata=output_axis_tdata,
tvalid=output_axis_tvalid,
tready=output_axis_tready,
tlast=output_axis_tlast,
tuser=output_axis_tuser,
fifo=sink_queue,
pause=sink_pause,
name='sink')
# DUT
dut = dut_axis_cobs_decode(clk,
rst,
current_test,
input_axis_tdata,
input_axis_tvalid,
input_axis_tready,
input_axis_tlast,
input_axis_tuser,
output_axis_tdata,
output_axis_tvalid,
output_axis_tready,
output_axis_tlast,
output_axis_tuser)
@always(delay(4))
def clkgen():
clk.next = not clk
def wait_normal():
i = 4
while i > 0:
i = max(0, i-1)
if input_axis_tvalid or output_axis_tvalid or not source_queue.empty():
i = 4
yield clk.posedge
def wait_pause_source():
i = 2
while i > 0:
i = max(0, i-1)
if input_axis_tvalid or output_axis_tvalid or not source_queue.empty():
i = 2
source_pause.next = True
yield clk.posedge
yield clk.posedge
yield clk.posedge
source_pause.next = False
yield clk.posedge
def wait_pause_sink():
i = 2
while i > 0:
i = max(0, i-1)
if input_axis_tvalid or output_axis_tvalid or not source_queue.empty():
i = 2
sink_pause.next = True
yield clk.posedge
yield clk.posedge
yield clk.posedge
sink_pause.next = False
yield clk.posedge
@instance
def check():
yield delay(100)
yield clk.posedge
rst.next = 1
yield clk.posedge
rst.next = 0
yield clk.posedge
yield delay(100)
yield clk.posedge
# testbench stimulus
for payload_len in list(range(1,33))+list(range(252,261))+[512,1024]:
gen = prbs31()
for block in [bytearray([0]*payload_len),
bytearray([k%255+1 for k in range(payload_len)]),
b'\x00'+bytearray([k%255+1 for k in range(payload_len)])+b'\x00',
bytearray([next(gen) for i in range(payload_len)])]:
yield clk.posedge
print("test 1: test packet, length %d" % payload_len)
current_test.next = 1
enc = cobs_encode(block)
test_frame = axis_ep.AXIStreamFrame(enc)
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
yield clk.posedge
print("test 2: test packet, length %d, zero frame" % payload_len)
current_test.next = 2
enc = cobs_encode(block)
test_frame = axis_ep.AXIStreamFrame(enc+b'\x00')
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
yield clk.posedge
print("test 3: back-to-back packets, length %d" % payload_len)
current_test.next = 3
test_frame2 = axis_ep.AXIStreamFrame(enc)
test_frame1 = axis_ep.AXIStreamFrame(enc)
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame1)
source_queue.put(test_frame2)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == block
assert not rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
yield clk.posedge
print("test 4: back-to-back packets, length %d, zero frame" % payload_len)
current_test.next = 4
test_frame = axis_ep.AXIStreamFrame(enc+b'\x00'+enc+b'\x00')
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == block
assert not rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
yield clk.posedge
print("test 5: tuser assert and bad frame, length %d" % payload_len)
current_test.next = 5
test_frame1 = axis_ep.AXIStreamFrame(enc)
test_frame2 = axis_ep.AXIStreamFrame(enc+b'\x02')
test_frame3 = axis_ep.AXIStreamFrame(enc)
test_frame1.user = 1
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame1)
source_queue.put(test_frame2)
source_queue.put(test_frame3)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
yield clk.posedge
print("test 6: tuser assert and bad frame, length %d, zero frame" % payload_len)
current_test.next = 6
test_frame1 = axis_ep.AXIStreamFrame(enc+b'\x00')
test_frame2 = axis_ep.AXIStreamFrame(enc+b'\x02\x00')
test_frame3 = axis_ep.AXIStreamFrame(enc+b'\x00')
test_frame1.user = 1
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame1)
source_queue.put(test_frame2)
source_queue.put(test_frame3)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
raise StopSimulation
return dut, source, sink, clkgen, check
def test_bench():
sim = Simulation(bench())
sim.run()
if __name__ == '__main__':
print("Running test...")
test_bench()

91
tb/test_axis_cobs_decode.v Normal file
View File

@ -0,0 +1,91 @@
/*
Copyright (c) 2016 Alex Forencich
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
// Language: Verilog 2001
`timescale 1ns / 1ps
/*
* Testbench for axis_cobs_decode
*/
module test_axis_cobs_decode;
// Parameters
// Inputs
reg clk = 0;
reg rst = 0;
reg [7:0] current_test = 0;
reg [7:0] input_axis_tdata = 0;
reg input_axis_tvalid = 0;
reg input_axis_tlast = 0;
reg input_axis_tuser = 0;
reg output_axis_tready = 0;
// Outputs
wire input_axis_tready;
wire [7:0] output_axis_tdata;
wire output_axis_tvalid;
wire output_axis_tlast;
wire output_axis_tuser;
initial begin
// myhdl integration
$from_myhdl(clk,
rst,
current_test,
input_axis_tdata,
input_axis_tvalid,
input_axis_tlast,
input_axis_tuser,
output_axis_tready);
$to_myhdl(input_axis_tready,
output_axis_tdata,
output_axis_tvalid,
output_axis_tlast,
output_axis_tuser);
// dump file
$dumpfile("test_axis_cobs_decode.lxt");
$dumpvars(0, test_axis_cobs_decode);
end
axis_cobs_decode
UUT (
.clk(clk),
.rst(rst),
.input_axis_tdata(input_axis_tdata),
.input_axis_tvalid(input_axis_tvalid),
.input_axis_tready(input_axis_tready),
.input_axis_tlast(input_axis_tlast),
.input_axis_tuser(input_axis_tuser),
.output_axis_tdata(output_axis_tdata),
.output_axis_tvalid(output_axis_tvalid),
.output_axis_tready(output_axis_tready),
.output_axis_tlast(output_axis_tlast),
.output_axis_tuser(output_axis_tuser)
);
endmodule

381
tb/test_axis_cobs_encode.py Executable file
View File

@ -0,0 +1,381 @@
#!/usr/bin/env python
"""
Copyright (c) 2016 Alex Forencich
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
"""
from myhdl import *
import os
try:
from queue import Queue
except ImportError:
from Queue import Queue
import axis_ep
module = 'axis_cobs_encode'
testbench = 'test_axis_cobs_encode'
srcs = []
srcs.append("../rtl/%s.v" % module)
srcs.append("../rtl/axis_fifo.v")
srcs.append("%s.v" % testbench)
src = ' '.join(srcs)
build_cmd = "iverilog -o %s.vvp %s" % (testbench, src)
def dut_axis_cobs_encode(clk,
rst,
current_test,
input_axis_tdata,
input_axis_tvalid,
input_axis_tready,
input_axis_tlast,
input_axis_tuser,
output_axis_tdata,
output_axis_tvalid,
output_axis_tready,
output_axis_tlast,
output_axis_tuser):
if os.system(build_cmd):
raise Exception("Error running build command")
return Cosimulation("vvp -m myhdl %s.vvp -lxt2" % testbench,
clk=clk,
rst=rst,
current_test=current_test,
input_axis_tdata=input_axis_tdata,
input_axis_tvalid=input_axis_tvalid,
input_axis_tready=input_axis_tready,
input_axis_tlast=input_axis_tlast,
input_axis_tuser=input_axis_tuser,
output_axis_tdata=output_axis_tdata,
output_axis_tvalid=output_axis_tvalid,
output_axis_tready=output_axis_tready,
output_axis_tlast=output_axis_tlast,
output_axis_tuser=output_axis_tuser)
def cobs_encode(block):
block = bytearray(block)
enc = bytearray()
seg = bytearray()
code = 1
new_data = True
for b in block:
if b == 0:
enc.append(code)
enc.extend(seg)
code = 1
seg = bytearray()
new_data = True
else:
code += 1
seg.append(b)
new_data = True
if code == 255:
enc.append(code)
enc.extend(seg)
code = 1
seg = bytearray()
new_data = False
if new_data:
enc.append(code)
enc.extend(seg)
return bytes(enc)
def cobs_decode(block):
block = bytearray(block)
dec = bytearray()
it = iter(bytearray(block))
code = 0
i = 0
if 0 in block:
return None
while i < len(block):
code = block[i]
i += 1
if i+code-1 > len(block):
return None
for k in range(code-1):
dec.append(block[i])
i += 1
if code < 255 and i < len(block):
dec.append(0)
return bytes(dec)
def prbs31(state = 0x7fffffff):
while True:
for i in range(8):
if bool(state & 0x08000000) ^ bool(state & 0x40000000):
state = ((state & 0x3fffffff) << 1) | 1
else:
state = (state & 0x3fffffff) << 1
yield state & 0xff
def bench():
# Parameters
APPEND_ZERO = 0
# Inputs
clk = Signal(bool(0))
rst = Signal(bool(0))
current_test = Signal(intbv(0)[8:])
input_axis_tdata = Signal(intbv(0)[8:])
input_axis_tvalid = Signal(bool(0))
input_axis_tlast = Signal(bool(0))
input_axis_tuser = Signal(bool(0))
output_axis_tready = Signal(bool(0))
# Outputs
input_axis_tready = Signal(bool(0))
output_axis_tdata = Signal(intbv(0)[8:])
output_axis_tvalid = Signal(bool(0))
output_axis_tlast = Signal(bool(0))
output_axis_tuser = Signal(bool(0))
# sources and sinks
source_queue = Queue()
source_pause = Signal(bool(0))
sink_queue = Queue()
sink_pause = Signal(bool(0))
source = axis_ep.AXIStreamSource(clk,
rst,
tdata=input_axis_tdata,
tvalid=input_axis_tvalid,
tready=input_axis_tready,
tlast=input_axis_tlast,
tuser=input_axis_tuser,
fifo=source_queue,
pause=source_pause,
name='source')
sink = axis_ep.AXIStreamSink(clk,
rst,
tdata=output_axis_tdata,
tvalid=output_axis_tvalid,
tready=output_axis_tready,
tlast=output_axis_tlast,
tuser=output_axis_tuser,
fifo=sink_queue,
pause=sink_pause,
name='sink')
# DUT
dut = dut_axis_cobs_encode(clk,
rst,
current_test,
input_axis_tdata,
input_axis_tvalid,
input_axis_tready,
input_axis_tlast,
input_axis_tuser,
output_axis_tdata,
output_axis_tvalid,
output_axis_tready,
output_axis_tlast,
output_axis_tuser)
@always(delay(4))
def clkgen():
clk.next = not clk
def wait_normal():
i = 4
while i > 0:
i = max(0, i-1)
if input_axis_tvalid or output_axis_tvalid or not source_queue.empty():
i = 4
yield clk.posedge
def wait_pause_source():
i = 2
while i > 0:
i = max(0, i-1)
if input_axis_tvalid or output_axis_tvalid or not source_queue.empty():
i = 2
source_pause.next = True
yield clk.posedge
yield clk.posedge
yield clk.posedge
source_pause.next = False
yield clk.posedge
def wait_pause_sink():
i = 2
while i > 0:
i = max(0, i-1)
if input_axis_tvalid or output_axis_tvalid or not source_queue.empty():
i = 2
sink_pause.next = True
yield clk.posedge
yield clk.posedge
yield clk.posedge
sink_pause.next = False
yield clk.posedge
@instance
def check():
yield delay(100)
yield clk.posedge
rst.next = 1
yield clk.posedge
rst.next = 0
yield clk.posedge
yield delay(100)
yield clk.posedge
# testbench stimulus
for payload_len in list(range(1,33))+list(range(252,261))+[512,1024]:
gen = prbs31()
for block in [bytearray([0]*payload_len),
bytearray([k%255+1 for k in range(payload_len)]),
b'\x00'+bytearray([k%255+1 for k in range(payload_len)])+b'\x00',
bytearray([next(gen) for i in range(payload_len)])]:
yield clk.posedge
print("test 1: test packet, length %d" % payload_len)
current_test.next = 1
enc = cobs_encode(block)
test_frame = axis_ep.AXIStreamFrame(block)
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == enc
assert cobs_decode(rx_frame.data) == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
yield clk.posedge
print("test 2: back-to-back packets, length %d" % payload_len)
current_test.next = 2
test_frame1 = axis_ep.AXIStreamFrame(block)
test_frame2 = axis_ep.AXIStreamFrame(block)
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame1)
source_queue.put(test_frame2)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == enc
assert cobs_decode(rx_frame.data) == block
assert not rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == enc
assert cobs_decode(rx_frame.data) == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
yield clk.posedge
print("test 3: tuser assert, length %d" % payload_len)
current_test.next = 3
test_frame1 = axis_ep.AXIStreamFrame(block)
test_frame2 = axis_ep.AXIStreamFrame(block)
test_frame1.user = 1
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame1)
source_queue.put(test_frame2)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(rx_frame.data) == None
assert rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == enc
assert cobs_decode(rx_frame.data) == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
raise StopSimulation
return dut, source, sink, clkgen, check
def test_bench():
sim = Simulation(bench())
sim.run()
if __name__ == '__main__':
print("Running test...")
test_bench()

94
tb/test_axis_cobs_encode.v Normal file
View File

@ -0,0 +1,94 @@
/*
Copyright (c) 2016 Alex Forencich
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
// Language: Verilog 2001
`timescale 1ns / 1ps
/*
* Testbench for axis_cobs_encode
*/
module test_axis_cobs_encode;
// Parameters
parameter APPEND_ZERO = 0;
// Inputs
reg clk = 0;
reg rst = 0;
reg [7:0] current_test = 0;
reg [7:0] input_axis_tdata = 0;
reg input_axis_tvalid = 0;
reg input_axis_tlast = 0;
reg input_axis_tuser = 0;
reg output_axis_tready = 0;
// Outputs
wire input_axis_tready;
wire [7:0] output_axis_tdata;
wire output_axis_tvalid;
wire output_axis_tlast;
wire output_axis_tuser;
initial begin
// myhdl integration
$from_myhdl(clk,
rst,
current_test,
input_axis_tdata,
input_axis_tvalid,
input_axis_tlast,
input_axis_tuser,
output_axis_tready);
$to_myhdl(input_axis_tready,
output_axis_tdata,
output_axis_tvalid,
output_axis_tlast,
output_axis_tuser);
// dump file
$dumpfile("test_axis_cobs_encode.lxt");
$dumpvars(0, test_axis_cobs_encode);
end
axis_cobs_encode #(
.APPEND_ZERO(APPEND_ZERO)
)
UUT (
.clk(clk),
.rst(rst),
.input_axis_tdata(input_axis_tdata),
.input_axis_tvalid(input_axis_tvalid),
.input_axis_tready(input_axis_tready),
.input_axis_tlast(input_axis_tlast),
.input_axis_tuser(input_axis_tuser),
.output_axis_tdata(output_axis_tdata),
.output_axis_tvalid(output_axis_tvalid),
.output_axis_tready(output_axis_tready),
.output_axis_tlast(output_axis_tlast),
.output_axis_tuser(output_axis_tuser)
);
endmodule

381
tb/test_axis_cobs_encode_zero_frame.py Executable file
View File

@ -0,0 +1,381 @@
#!/usr/bin/env python
"""
Copyright (c) 2016 Alex Forencich
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
"""
from myhdl import *
import os
try:
from queue import Queue
except ImportError:
from Queue import Queue
import axis_ep
module = 'axis_cobs_encode'
testbench = 'test_axis_cobs_encode_zero_frame'
srcs = []
srcs.append("../rtl/%s.v" % module)
srcs.append("../rtl/axis_fifo.v")
srcs.append("%s.v" % testbench)
src = ' '.join(srcs)
build_cmd = "iverilog -o %s.vvp %s" % (testbench, src)
def dut_axis_cobs_encode(clk,
rst,
current_test,
input_axis_tdata,
input_axis_tvalid,
input_axis_tready,
input_axis_tlast,
input_axis_tuser,
output_axis_tdata,
output_axis_tvalid,
output_axis_tready,
output_axis_tlast,
output_axis_tuser):
if os.system(build_cmd):
raise Exception("Error running build command")
return Cosimulation("vvp -m myhdl %s.vvp -lxt2" % testbench,
clk=clk,
rst=rst,
current_test=current_test,
input_axis_tdata=input_axis_tdata,
input_axis_tvalid=input_axis_tvalid,
input_axis_tready=input_axis_tready,
input_axis_tlast=input_axis_tlast,
input_axis_tuser=input_axis_tuser,
output_axis_tdata=output_axis_tdata,
output_axis_tvalid=output_axis_tvalid,
output_axis_tready=output_axis_tready,
output_axis_tlast=output_axis_tlast,
output_axis_tuser=output_axis_tuser)
def cobs_encode(block):
block = bytearray(block)
enc = bytearray()
seg = bytearray()
code = 1
new_data = True
for b in block:
if b == 0:
enc.append(code)
enc.extend(seg)
code = 1
seg = bytearray()
new_data = True
else:
code += 1
seg.append(b)
new_data = True
if code == 255:
enc.append(code)
enc.extend(seg)
code = 1
seg = bytearray()
new_data = False
if new_data:
enc.append(code)
enc.extend(seg)
return bytes(enc)
def cobs_decode(block):
block = bytearray(block)
dec = bytearray()
it = iter(bytearray(block))
code = 0
i = 0
if 0 in block:
return None
while i < len(block):
code = block[i]
i += 1
if i+code-1 > len(block):
return None
for k in range(code-1):
dec.append(block[i])
i += 1
if code < 255 and i < len(block):
dec.append(0)
return bytes(dec)
def prbs31(state = 0x7fffffff):
while True:
for i in range(8):
if bool(state & 0x08000000) ^ bool(state & 0x40000000):
state = ((state & 0x3fffffff) << 1) | 1
else:
state = (state & 0x3fffffff) << 1
yield state & 0xff
def bench():
# Parameters
APPEND_ZERO = 1
# Inputs
clk = Signal(bool(0))
rst = Signal(bool(0))
current_test = Signal(intbv(0)[8:])
input_axis_tdata = Signal(intbv(0)[8:])
input_axis_tvalid = Signal(bool(0))
input_axis_tlast = Signal(bool(0))
input_axis_tuser = Signal(bool(0))
output_axis_tready = Signal(bool(0))
# Outputs
input_axis_tready = Signal(bool(0))
output_axis_tdata = Signal(intbv(0)[8:])
output_axis_tvalid = Signal(bool(0))
output_axis_tlast = Signal(bool(0))
output_axis_tuser = Signal(bool(0))
# sources and sinks
source_queue = Queue()
source_pause = Signal(bool(0))
sink_queue = Queue()
sink_pause = Signal(bool(0))
source = axis_ep.AXIStreamSource(clk,
rst,
tdata=input_axis_tdata,
tvalid=input_axis_tvalid,
tready=input_axis_tready,
tlast=input_axis_tlast,
tuser=input_axis_tuser,
fifo=source_queue,
pause=source_pause,
name='source')
sink = axis_ep.AXIStreamSink(clk,
rst,
tdata=output_axis_tdata,
tvalid=output_axis_tvalid,
tready=output_axis_tready,
tlast=output_axis_tlast,
tuser=output_axis_tuser,
fifo=sink_queue,
pause=sink_pause,
name='sink')
# DUT
dut = dut_axis_cobs_encode(clk,
rst,
current_test,
input_axis_tdata,
input_axis_tvalid,
input_axis_tready,
input_axis_tlast,
input_axis_tuser,
output_axis_tdata,
output_axis_tvalid,
output_axis_tready,
output_axis_tlast,
output_axis_tuser)
@always(delay(4))
def clkgen():
clk.next = not clk
def wait_normal():
i = 4
while i > 0:
i = max(0, i-1)
if input_axis_tvalid or output_axis_tvalid or not source_queue.empty():
i = 4
yield clk.posedge
def wait_pause_source():
i = 2
while i > 0:
i = max(0, i-1)
if input_axis_tvalid or output_axis_tvalid or not source_queue.empty():
i = 2
source_pause.next = True
yield clk.posedge
yield clk.posedge
yield clk.posedge
source_pause.next = False
yield clk.posedge
def wait_pause_sink():
i = 2
while i > 0:
i = max(0, i-1)
if input_axis_tvalid or output_axis_tvalid or not source_queue.empty():
i = 2
sink_pause.next = True
yield clk.posedge
yield clk.posedge
yield clk.posedge
sink_pause.next = False
yield clk.posedge
@instance
def check():
yield delay(100)
yield clk.posedge
rst.next = 1
yield clk.posedge
rst.next = 0
yield clk.posedge
yield delay(100)
yield clk.posedge
# testbench stimulus
for payload_len in list(range(1,33))+list(range(252,261))+[512,1024]:
gen = prbs31()
for block in [bytearray([0]*payload_len),
bytearray([k%255+1 for k in range(payload_len)]),
b'\x00'+bytearray([k%255+1 for k in range(payload_len)])+b'\x00',
bytearray([next(gen) for i in range(payload_len)])]:
yield clk.posedge
print("test 1: test packet, length %d" % payload_len)
current_test.next = 1
enc = cobs_encode(block)
test_frame = axis_ep.AXIStreamFrame(block)
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == enc+b'\x00'
assert cobs_decode(rx_frame.data[:-1]) == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
yield clk.posedge
print("test 2: back-to-back packets, length %d" % payload_len)
current_test.next = 2
test_frame1 = axis_ep.AXIStreamFrame(block)
test_frame2 = axis_ep.AXIStreamFrame(block)
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame1)
source_queue.put(test_frame2)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == enc+b'\x00'
assert cobs_decode(rx_frame.data[:-1]) == block
assert not rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == enc+b'\x00'
assert cobs_decode(rx_frame.data[:-1]) == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
yield clk.posedge
print("test 3: tuser assert, length %d" % payload_len)
current_test.next = 3
test_frame1 = axis_ep.AXIStreamFrame(block)
test_frame2 = axis_ep.AXIStreamFrame(block)
test_frame1.user = 1
for wait in wait_normal, wait_pause_source, wait_pause_sink:
source_queue.put(test_frame1)
source_queue.put(test_frame2)
yield clk.posedge
yield clk.posedge
yield wait()
yield clk.posedge
yield clk.posedge
rx_frame = sink_queue.get(False)
assert cobs_decode(rx_frame.data[:-1]) == None
assert rx_frame.user[-1]
rx_frame = sink_queue.get(False)
assert cobs_decode(enc) == block
assert rx_frame.data == enc+b'\x00'
assert cobs_decode(rx_frame.data[:-1]) == block
assert not rx_frame.user[-1]
assert sink_queue.empty()
yield delay(100)
raise StopSimulation
return dut, source, sink, clkgen, check
def test_bench():
sim = Simulation(bench())
sim.run()
if __name__ == '__main__':
print("Running test...")
test_bench()

94
tb/test_axis_cobs_encode_zero_frame.v Normal file
View File

@ -0,0 +1,94 @@
/*
Copyright (c) 2016 Alex Forencich
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
*/
// Language: Verilog 2001
`timescale 1ns / 1ps
/*
* Testbench for axis_cobs_encode
*/
module test_axis_cobs_encode_zero_frame;
// Parameters
parameter APPEND_ZERO = 1;
// Inputs
reg clk = 0;
reg rst = 0;
reg [7:0] current_test = 0;
reg [7:0] input_axis_tdata = 0;
reg input_axis_tvalid = 0;
reg input_axis_tlast = 0;
reg input_axis_tuser = 0;
reg output_axis_tready = 0;
// Outputs
wire input_axis_tready;
wire [7:0] output_axis_tdata;
wire output_axis_tvalid;
wire output_axis_tlast;
wire output_axis_tuser;
initial begin
// myhdl integration
$from_myhdl(clk,
rst,
current_test,
input_axis_tdata,
input_axis_tvalid,
input_axis_tlast,
input_axis_tuser,
output_axis_tready);
$to_myhdl(input_axis_tready,
output_axis_tdata,
output_axis_tvalid,
output_axis_tlast,
output_axis_tuser);
// dump file
$dumpfile("test_axis_cobs_encode_zero_frame.lxt");
$dumpvars(0, test_axis_cobs_encode_zero_frame);
end
axis_cobs_encode #(
.APPEND_ZERO(APPEND_ZERO)
)
UUT (
.clk(clk),
.rst(rst),
.input_axis_tdata(input_axis_tdata),
.input_axis_tvalid(input_axis_tvalid),
.input_axis_tready(input_axis_tready),
.input_axis_tlast(input_axis_tlast),
.input_axis_tuser(input_axis_tuser),
.output_axis_tdata(output_axis_tdata),
.output_axis_tvalid(output_axis_tvalid),
.output_axis_tready(output_axis_tready),
.output_axis_tlast(output_axis_tlast),
.output_axis_tuser(output_axis_tuser)
);
endmodule