diff options
Diffstat (limited to 'fpga/usrp2/vrt/vita_tx_control.v')
| -rw-r--r-- | fpga/usrp2/vrt/vita_tx_control.v | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/fpga/usrp2/vrt/vita_tx_control.v b/fpga/usrp2/vrt/vita_tx_control.v new file mode 100644 index 000000000..20ad6b995 --- /dev/null +++ b/fpga/usrp2/vrt/vita_tx_control.v @@ -0,0 +1,174 @@ + +module vita_tx_control + #(parameter BASE=0, + parameter WIDTH=32) + (input clk, input reset, input clear, + input set_stb, input [7:0] set_addr, input [31:0] set_data, + + input [63:0] vita_time, + output error, output ack, + output reg [31:0] error_code, + output reg packet_consumed, + + // From vita_tx_deframer + input [5+64+16+WIDTH-1:0] sample_fifo_i, + input sample_fifo_src_rdy_i, + output sample_fifo_dst_rdy_o, + + // To DSP Core + output [WIDTH-1:0] sample, + output run, + input strobe, + + output [31:0] debug + ); + + assign sample = sample_fifo_i[5+64+16+WIDTH-1:5+64+16]; + + wire [63:0] send_time = sample_fifo_i[63:0]; + wire [15:0] seqnum = sample_fifo_i[79:64]; + wire eop = sample_fifo_i[80]; + wire eob = sample_fifo_i[81]; + wire sob = sample_fifo_i[82]; + wire send_at = sample_fifo_i[83]; + wire seqnum_err = sample_fifo_i[84]; + + wire now, early, late, too_early; + + // FIXME ignore too_early for now for timing reasons + assign too_early = 0; + time_compare + time_compare (.time_now(vita_time), .trigger_time(send_time), + .now(now), .early(early), .late(late), .too_early()); + + localparam IBS_IDLE = 0; + localparam IBS_RUN = 1; // FIXME do we need this? + localparam IBS_CONT_BURST = 2; + localparam IBS_ERROR = 3; + localparam IBS_ERROR_DONE = 4; + localparam IBS_ERROR_WAIT = 5; + + wire [31:0] CODE_EOB_ACK = {seqnum,16'd1}; + wire [31:0] CODE_UNDERRUN = {seqnum,16'd2}; + wire [31:0] CODE_SEQ_ERROR = {seqnum,16'd4}; + wire [31:0] CODE_TIME_ERROR = {seqnum,16'd8}; + wire [31:0] CODE_UNDERRUN_MIDPKT = {seqnum,16'd16}; + wire [31:0] CODE_SEQ_ERROR_MIDBURST = {seqnum,16'd32}; + + reg [2:0] ibs_state; + + wire [31:0] error_policy; + setting_reg #(.my_addr(BASE+3)) sr_error_policy + (.clk(clk),.rst(rst),.strobe(set_stb),.addr(set_addr), + .in(set_data),.out(error_policy),.changed()); + + wire policy_wait = error_policy[0]; + wire policy_next_packet = error_policy[1]; + wire policy_next_burst = error_policy[2]; + reg send_error, send_ack; + + always @(posedge clk) + if(reset | clear) + begin + ibs_state <= IBS_IDLE; + send_error <= 0; + send_ack <= 0; + error_code <= 0; + end + else + case(ibs_state) + IBS_IDLE : + if(sample_fifo_src_rdy_i) + if(seqnum_err) + begin + ibs_state <= IBS_ERROR; + error_code <= CODE_SEQ_ERROR; + send_error <= 1; + end + else if(~send_at | now) + ibs_state <= IBS_RUN; + else if(late | too_early) + begin + ibs_state <= IBS_ERROR; + error_code <= CODE_TIME_ERROR; + send_error <= 1; + end + + IBS_RUN : + if(strobe) + if(~sample_fifo_src_rdy_i) + begin + ibs_state <= IBS_ERROR; + error_code <= CODE_UNDERRUN_MIDPKT; + send_error <= 1; + end + else if(eop) + if(eob) + begin + ibs_state <= IBS_ERROR_DONE; // Not really an error + error_code <= CODE_EOB_ACK; + send_ack <= 1; + end + else + ibs_state <= IBS_CONT_BURST; + + IBS_CONT_BURST : + if(strobe) + begin + if(policy_next_packet) + ibs_state <= IBS_ERROR_DONE; + else if(policy_wait) + ibs_state <= IBS_ERROR_WAIT; + else + ibs_state <= IBS_ERROR; + error_code <= CODE_UNDERRUN; + send_error <= 1; + end + else if(sample_fifo_src_rdy_i) + if(seqnum_err) + begin + ibs_state <= IBS_ERROR; + error_code <= CODE_SEQ_ERROR_MIDBURST; + send_error <= 1; + end + else + ibs_state <= IBS_RUN; + + IBS_ERROR : + begin + send_error <= 0; + if(sample_fifo_src_rdy_i & eop) + if(policy_next_packet | (policy_next_burst & eob)) + ibs_state <= IBS_IDLE; + else if(policy_wait) + ibs_state <= IBS_ERROR_WAIT; + end + + IBS_ERROR_DONE : + begin + send_error <= 0; + send_ack <= 0; + ibs_state <= IBS_IDLE; + end + + IBS_ERROR_WAIT : + send_error <= 0; + endcase // case (ibs_state) + + assign sample_fifo_dst_rdy_o = (ibs_state == IBS_ERROR) | (strobe & (ibs_state == IBS_RUN)); // FIXME also cleanout + assign run = (ibs_state == IBS_RUN) | (ibs_state == IBS_CONT_BURST); + assign error = send_error; + assign ack = send_ack; + + always @(posedge clk) + if(reset | clear) + packet_consumed <= 0; + else + packet_consumed <= eop & sample_fifo_src_rdy_i & sample_fifo_dst_rdy_o; + + assign debug = { { now,early,late,ack,eop,eob,sob,send_at }, + { sample_fifo_src_rdy_i, sample_fifo_dst_rdy_o, strobe, run, error, ibs_state[2:0] }, + { 8'b0 }, + { 8'b0 } }; + +endmodule // vita_tx_control |