1
0
mirror of https://github.com/aolofsson/oh.git synced 2025-01-17 20:02:53 +08:00
oh/elink/hdl/erx_protocol.v
2020-01-28 18:12:57 -05:00

71 lines
1.9 KiB
Verilog

//############################################################
//#This block handles the autoincrement needed for bursting
//############################################################
module erx_protocol (/*AUTOARG*/
// Outputs
erx_access, erx_packet,
// Inputs
clk, test_mode, rx_packet, rx_burst, rx_access
);
parameter AW = 32;
parameter DW = 32;
parameter PW = 104;
parameter ID = 12'h999; //link id
// System reset input
input clk;
//test mode
input test_mode; //block all traffic in test mode
// Parallel interface, 8 eLink bytes at a time
input [PW-1:0] rx_packet;
input rx_burst;
input rx_access;
// Output to MMU / filter
output erx_access;
output [PW-1:0] erx_packet;
//wires
reg [31:0] dstaddr_reg;
wire [31:0] dstaddr_next;
wire [31:0] dstaddr_mux;
reg erx_access;
reg [PW-1:0] erx_packet;
wire [31:0] rx_addr;
//parsing inputs
assign rx_addr[31:0] = rx_packet[39:8];
//Address generator for bursting
always @ (posedge clk)
if(rx_access)
dstaddr_reg[31:0] <= dstaddr_mux[31:0];
assign dstaddr_next[31:0] = dstaddr_reg[31:0] + 4'b1000;
assign dstaddr_mux[31:0] = rx_burst ? dstaddr_next[31:0] :
rx_addr[31:0];
//Pipeline stage and decode
always @ (posedge clk)
begin
//Write/read request
erx_access <= ~test_mode & rx_access;
//Common packet
erx_packet[PW-1:0] <= {rx_packet[PW-1:40],
dstaddr_mux[31:0],
{1'b0,rx_packet[7:1]} //NOTE: remvoing redundant access packet bit
}; //This is to conform to new format
end
endmodule // erx_protocol
// Local Variables:
// verilog-library-directories:("." "../../common/hdl")
// End: