serv/servant/servant_timer.v
2020-11-10 15:16:19 +01:00

37 lines
866 B
Verilog

`default_nettype none
module servant_timer
#(parameter WIDTH = 16,
parameter RESET_STRATEGY = "",
parameter DIVIDER = 0)
(input wire i_clk,
input wire i_rst,
output reg o_irq,
input wire [31:0] i_wb_dat,
input wire i_wb_we,
input wire i_wb_cyc,
output reg [31:0] o_wb_dat);
localparam HIGH = WIDTH-1-DIVIDER;
reg [WIDTH-1:0] mtime;
reg [HIGH:0] mtimecmp;
wire [HIGH:0] mtimeslice = mtime[WIDTH-1:DIVIDER];
always @(mtimeslice) begin
o_wb_dat = 32'd0;
o_wb_dat[HIGH:0] = mtimeslice;
end
always @(posedge i_clk) begin
if (i_wb_cyc & i_wb_we)
mtimecmp <= i_wb_dat[HIGH:0];
mtime <= mtime + 'd1;
o_irq <= (mtimeslice >= mtimecmp);
if (RESET_STRATEGY != "NONE")
if (i_rst) begin
mtime <= 0;
mtimecmp <= 0;
end
end
endmodule