diff options
Diffstat (limited to 'eth/rtl/verilog/flow_ctrl_rx.v')
| -rw-r--r-- | eth/rtl/verilog/flow_ctrl_rx.v | 86 |
1 files changed, 0 insertions, 86 deletions
diff --git a/eth/rtl/verilog/flow_ctrl_rx.v b/eth/rtl/verilog/flow_ctrl_rx.v deleted file mode 100644 index 6654c626b..000000000 --- a/eth/rtl/verilog/flow_ctrl_rx.v +++ /dev/null @@ -1,86 +0,0 @@ -
-// RX side of flow control -- when we are running out of RX space, send a PAUSE
-
-module flow_ctrl_rx
- (input rst,
- //host processor
- input pause_frame_send_en,
- input [15:0] pause_quanta_set,
- input [15:0] fc_hwmark,
- input [15:0] fc_lwmark,
- input [15:0] fc_padtime,
- // From MAC_rx_ctrl
- input rx_clk,
- input [15:0] rx_fifo_space,
- // MAC_tx_ctrl
- input tx_clk,
- output reg xoff_gen,
- output reg xon_gen,
- input xoff_gen_complete,
- input xon_gen_complete
- );
-
- // ******************************************************************************
- // Force our TX to send a PAUSE frame because our RX is nearly full
- // ******************************************************************************
-
- reg xon_int, xoff_int;
- reg [21:0] countdown;
-
- always @(posedge rx_clk or posedge rst)
- if(rst)
- begin
- xon_int <= 0;
- xoff_int <= 0;
- end
- else
- begin
- xon_int <= 0;
- xoff_int <= 0;
- if(pause_frame_send_en)
- if(countdown == 0)
- if(rx_fifo_space < fc_lwmark)
- xoff_int <= 1;
- else
- ;
- else
- if(rx_fifo_space > fc_hwmark)
- xon_int <= 1;
- end // else: !if(rst)
-
- reg xoff_int_d1, xon_int_d1;
-
- always @(posedge rx_clk)
- xon_int_d1 <= xon_int;
- always @(posedge rx_clk)
- xoff_int_d1 <= xoff_int;
-
- always @ (posedge tx_clk or posedge rst)
- if (rst)
- xoff_gen <=0;
- else if (xoff_gen_complete)
- xoff_gen <=0;
- else if (xoff_int | xoff_int_d1)
- xoff_gen <=1;
-
- always @ (posedge tx_clk or posedge rst)
- if (rst)
- xon_gen <=0;
- else if (xon_gen_complete)
- xon_gen <=0;
- else if (xon_int | xon_int_d1)
- xon_gen <=1;
-
- wire [21:0] pq_reduced = {pause_quanta_set,6'd0} - {6'd0,fc_padtime};
-
- always @(posedge tx_clk or posedge rst)
- if(rst)
- countdown <= 0;
- else if(xoff_gen)
- countdown <= pq_reduced;
- else if(xon_gen)
- countdown <= 0;
- else if(countdown != 0)
- countdown <= countdown - 1;
-
-endmodule // flow_ctrl
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