Files
UHD-Fairwaves/fpga/control_lib/settings_fifo_ctrl.v
2015-07-22 20:05:19 -07:00

413 lines
14 KiB
Verilog

//
// Copyright 2012 Ettus Research LLC
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
//
// A settings and readback bus controlled via fifo36 interface
module settings_fifo_ctrl
#(
parameter XPORT_HDR = 1, //extra transport hdr line
parameter PROT_DEST = 0, //protocol framer destination
parameter PROT_HDR = 1, //needs a protocol header?
parameter ACK_SID = 0, //stream ID for packet ACK
parameter DEPTH = 6 //size of fifo in addr bit width
)
(
//clock and synchronous reset for all interfaces
input clock, input reset, input clear,
//current system time
input [63:0] vita_time,
//ready signal for multiple peripherals
input perfs_ready,
//input fifo36 interface control
input [35:0] in_data, input in_valid, output in_ready,
//output fifo36 interface status
output [35:0] out_data, output out_valid, input out_ready,
//32-bit settings bus outputs
output strobe, output [7:0] addr, output [31:0] data,
//16X 32-bit inputs for readback
input [31:0] word00,
input [31:0] word01,
input [31:0] word02,
input [31:0] word03,
input [31:0] word04,
input [31:0] word05,
input [31:0] word06,
input [31:0] word07,
input [31:0] word08,
input [31:0] word09,
input [31:0] word10,
input [31:0] word11,
input [31:0] word12,
input [31:0] word13,
input [31:0] word14,
input [31:0] word15,
//debug output
output [31:0] debug
);
wire reading = in_valid && in_ready;
wire writing = out_valid && out_ready;
//------------------------------------------------------------------
//-- The command fifo:
//-- Stores an individual register access command per line.
//------------------------------------------------------------------
wire [63:0] in_command_ticks, out_command_ticks;
wire [31:0] in_command_hdr, out_command_hdr;
wire [31:0] in_command_data, out_command_data;
wire command_fifo_full, command_fifo_empty;
wire command_fifo_read, command_fifo_write;
wire [15:0] command_fifo_occupied;
longfifo #(.WIDTH(128), .SIZE(DEPTH)) command_fifo (
.clk(clock), .rst(reset), .clear(clear),
.datain({in_command_ticks, in_command_hdr, in_command_data}),
.dataout({out_command_ticks, out_command_hdr, out_command_data}),
.write(command_fifo_write), .full(command_fifo_full), //input interface
.empty(command_fifo_empty), .read(command_fifo_read), //output interface
.occupied(command_fifo_occupied)
);
//------------------------------------------------------------------
//-- The result fifo:
//-- Stores an individual result of a command per line.
//------------------------------------------------------------------
wire [31:0] in_result_hdr, out_result_hdr;
wire [31:0] in_result_data, out_result_data;
wire result_fifo_full, result_fifo_empty;
wire result_fifo_read, result_fifo_write;
wire [15:0] result_fifo_occupied;
longfifo #(.WIDTH(64), .SIZE(DEPTH)) result_fifo (
.clk(clock), .rst(reset), .clear(clear),
.datain({in_result_hdr, in_result_data}),
.dataout({out_result_hdr, out_result_data}),
.write(result_fifo_write), .full(result_fifo_full), //input interface
.empty(result_fifo_empty), .read(result_fifo_read), //output interface
.occupied(result_fifo_occupied)
);
//------------------------------------------------------------------
//-- Input state machine:
//-- Read input packet and fill a command fifo entry.
//------------------------------------------------------------------
localparam READ_LINE0 = 0;
localparam VITA_HDR = 1;
localparam VITA_SID = 2;
localparam VITA_CID0 = 3;
localparam VITA_CID1 = 4;
localparam VITA_TSI = 5;
localparam VITA_TSF0 = 6;
localparam VITA_TSF1 = 7;
localparam READ_HDR = 8;
localparam READ_DATA = 9;
localparam WAIT_EOF = 10;
localparam STORE_CMD = 11;
localparam START_STATE = (XPORT_HDR)? READ_LINE0 : VITA_HDR;
reg [4:0] in_state;
//holdover from current read inputs
reg [31:0] in_data_reg, in_hdr_reg;
reg [63:0] in_ticks_reg;
wire has_sid = in_data[28];
wire has_cid = in_data[27];
wire has_tsi = in_data[23:22] != 0;
wire has_tsf = in_data[21:20] != 0;
reg has_sid_reg, has_cid_reg, has_tsi_reg, has_tsf_reg;
assign in_ready = (in_state < STORE_CMD);
assign command_fifo_write = (in_state == STORE_CMD);
assign in_command_ticks = in_ticks_reg;
assign in_command_data = in_data_reg;
assign in_command_hdr = in_hdr_reg;
always @(posedge clock) begin
if (reset) begin
in_state <= START_STATE;
end
else begin
case (in_state)
READ_LINE0: begin
if (reading) in_state <= VITA_HDR;
end
VITA_HDR: begin
if (reading) begin
if (has_sid) in_state <= VITA_SID;
else if (has_cid) in_state <= VITA_CID0;
else if (has_tsi) in_state <= VITA_TSI;
else if (has_tsf) in_state <= VITA_TSF0;
else in_state <= READ_HDR;
end
has_sid_reg <= has_sid;
has_cid_reg <= has_cid;
has_tsi_reg <= has_tsi;
has_tsf_reg <= has_tsf;
end
VITA_SID: begin
if (reading) begin
if (has_cid_reg) in_state <= VITA_CID0;
else if (has_tsi_reg) in_state <= VITA_TSI;
else if (has_tsf_reg) in_state <= VITA_TSF0;
else in_state <= READ_HDR;
end
end
VITA_CID0: begin
if (reading) in_state <= VITA_CID1;
end
VITA_CID1: begin
if (reading) begin
if (has_tsi_reg) in_state <= VITA_TSI;
else if (has_tsf_reg) in_state <= VITA_TSF0;
else in_state <= READ_HDR;
end
end
VITA_TSI: begin
if (reading) begin
if (has_tsf_reg) in_state <= VITA_TSF0;
else in_state <= READ_HDR;
end
end
VITA_TSF0: begin
if (reading) in_state <= VITA_TSF1;
in_ticks_reg[63:32] <= in_data;
end
VITA_TSF1: begin
if (reading) in_state <= READ_HDR;
in_ticks_reg[31:0] <= in_data;
end
READ_HDR: begin
if (reading) in_state <= READ_DATA;
in_hdr_reg <= in_data[31:0];
end
READ_DATA: begin
if (reading) in_state <= (in_data[33])? STORE_CMD : WAIT_EOF;
in_data_reg <= in_data[31:0];
end
WAIT_EOF: begin
if (reading && in_data[33]) in_state <= STORE_CMD;
end
STORE_CMD: begin
if (~command_fifo_full) in_state <= START_STATE;
end
endcase //in_state
end
end
//------------------------------------------------------------------
//-- Command state machine:
//-- Read a command fifo entry, act on it, produce result.
//------------------------------------------------------------------
localparam LOAD_CMD = 0;
localparam EVENT_CMD = 1;
reg cmd_state;
reg [31:0] rb_data;
reg [63:0] command_ticks_reg;
reg [31:0] command_hdr_reg;
reg [31:0] command_data_reg;
reg [63:0] vita_time_reg;
always @(posedge clock)
vita_time_reg <= vita_time;
wire late, now;
`ifndef FIFO_CTRL_NO_TIME
time_compare time_compare(
.time_now(vita_time_reg), .trigger_time(command_ticks_reg), .late(late), .now(now));
`else
assign late = 1;
assign now = 1;
`endif
//these config flags are available only in the LOAD_CMD state (where we wait)
wire time_wait = out_command_hdr[9];
wire skip_late = out_command_hdr[10]; //TODO (implement)
reg cmd_was_late;
//action occurs in the event state and when there is fifo space (should always be true)
//the third condition is that all peripherals in the perfs signal are ready/active high
//the fourth condition is that is an event time has been set, action is delayed until that time
wire time_ready = (time_wait)? (late || now) : 1;
wire action = (cmd_state == EVENT_CMD) && ~result_fifo_full && perfs_ready && time_ready;
assign command_fifo_read = action;
assign result_fifo_write = action;
assign in_result_hdr = command_hdr_reg;
assign in_result_data = rb_data;
always @(posedge clock) begin
if (reset) begin
cmd_state <= LOAD_CMD;
end
else begin
case (cmd_state)
LOAD_CMD: begin
if (~command_fifo_empty) cmd_state <= EVENT_CMD;
command_ticks_reg <= out_command_ticks;
command_hdr_reg <= out_command_hdr;
command_data_reg <= out_command_data;
cmd_was_late <= late; //TODO do something with
end
EVENT_CMD: begin // poking and peeking happens here!
if (action || clear) cmd_state <= LOAD_CMD;
end
endcase //cmd_state
end
end
//------------------------------------------------------------------
//-- assign to settings bus interface
//------------------------------------------------------------------
reg strobe_reg;
assign strobe = strobe_reg;
assign data = command_data_reg;
assign addr = command_hdr_reg[7:0];
wire poke = command_hdr_reg[8];
always @(posedge clock) begin
if (reset || clear) strobe_reg <= 0;
else strobe_reg <= action && poke;
end
//------------------------------------------------------------------
//-- readback mux
//------------------------------------------------------------------
always @(posedge clock) begin
case (out_command_hdr[3:0])
0 : rb_data <= word00;
1 : rb_data <= word01;
2 : rb_data <= word02;
3 : rb_data <= word03;
4 : rb_data <= word04;
5 : rb_data <= word05;
6 : rb_data <= word06;
7 : rb_data <= word07;
8 : rb_data <= word08;
9 : rb_data <= word09;
10: rb_data <= word10;
11: rb_data <= word11;
12: rb_data <= word12;
13: rb_data <= word13;
14: rb_data <= word14;
15: rb_data <= word15;
endcase // case(addr_reg[3:0])
end
//------------------------------------------------------------------
//-- Output state machine:
//-- Read a command fifo entry, act on it, produce ack packet.
//------------------------------------------------------------------
localparam WRITE_PROT_HDR = 0;
localparam WRITE_VRT_HDR = 1;
localparam WRITE_VRT_SID = 2;
localparam WRITE_RB_HDR = 3;
localparam WRITE_RB_DATA = 4;
localparam WRITE_RB_DATA2 = 5;
localparam WRITE_RB_DATA3 = 6;
//the state for the start of packet condition
localparam WRITE_PKT_HDR = (PROT_HDR)? WRITE_PROT_HDR : WRITE_VRT_HDR;
reg [2:0] out_state;
reg [31:0] last_result_hdr;
assign out_valid = ~result_fifo_empty;
assign result_fifo_read = out_data[33] && writing;
always @(posedge clock) begin
if (reset) begin
out_state <= WRITE_PKT_HDR;
last_result_hdr <= 32'b0;
end
else if (writing && out_data[33]) begin
out_state <= WRITE_PKT_HDR;
last_result_hdr <= out_result_hdr;
end
else if (writing) begin
out_state <= out_state + 1;
end
end
//------------------------------------------------------------------
//-- assign to output fifo interface
//------------------------------------------------------------------
wire [31:0] prot_hdr;
assign prot_hdr[15:0] = 24; //bytes in proceeding vita packet
assign prot_hdr[16] = 1; //yes frame
assign prot_hdr[18:17] = PROT_DEST;
assign prot_hdr[31:19] = 0; //nothing
reg [31:0] out_data_int;
always @* begin
case (out_state)
WRITE_PROT_HDR: out_data_int <= prot_hdr;
WRITE_VRT_HDR: out_data_int <= {12'b010100000000, out_result_hdr[19:16], 2'b0, prot_hdr[15:2]};
WRITE_VRT_SID: out_data_int <= ACK_SID;
WRITE_RB_HDR: out_data_int <= out_result_hdr;
WRITE_RB_DATA: out_data_int <= out_result_data;
WRITE_RB_DATA2: out_data_int <= last_result_hdr;
WRITE_RB_DATA3: out_data_int <= {result_fifo_occupied, command_fifo_occupied};
default: out_data_int <= 0;
endcase //state
end
assign out_data[35:34] = 2'b0;
assign out_data[33] = (out_state == WRITE_RB_DATA3);
assign out_data[32] = (out_state == WRITE_PKT_HDR);
assign out_data[31:0] = out_data_int;
//------------------------------------------------------------------
//-- debug outputs
//------------------------------------------------------------------
assign debug = {
in_state, out_state, //8
in_valid, in_ready, in_data[33:32], //4
out_valid, out_ready, out_data[33:32], //4
command_fifo_empty, command_fifo_full, //2
command_fifo_read, command_fifo_write, //2
addr, //8
strobe_reg, strobe, poke, time_wait //4
};
endmodule //settings_fifo_ctrl