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Line 6... |
input [`NUM_PORTS-1:0] rarb_req,
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input [`NUM_PORTS-1:0] rarb_req,
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output reg [`NUM_PORTS-1:0] rarb_ack
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output reg [`NUM_PORTS-1:0] rarb_ack
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);
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);
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integer i;
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integer i;
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reg [`NUM_PORTS-1:0] nxt_rarb_ack;
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reg [`NUM_PORTS-1:0] nxt_rarb_ack;
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reg [$clog2(`NUM_PORTS)-1:0] nxt_ack;
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//reg [$clog2(`NUM_PORTS)-1:0] nxt_ack;
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function [`NUM_PORTS-1:0] nxt_grant;
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input [`NUM_PORTS-1:0] cur_grant;
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input [`NUM_PORTS-1:0] cur_req;
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reg [`NUM_PORTS-1:0] msk_req;
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reg [`NUM_PORTS-1:0] tmp_grant;
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begin
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msk_req = cur_req & ~((cur_grant - 1) | cur_grant);
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tmp_grant = msk_req & (~msk_req + 1);
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if (msk_req != 0)
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nxt_grant = tmp_grant;
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else
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nxt_grant = cur_req & (~cur_req + 1);
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end
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endfunction // if
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//assign nxt_rarb_ack = nxt_grant (rarb_ack, rarb_req);
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always @*
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always @*
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begin
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begin
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nxt_rarb_ack = rarb_ack;
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nxt_rarb_ack = rarb_ack;
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nxt_ack = 0;
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if (rarb_req == 0)
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if (rarb_req == 0)
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nxt_rarb_ack = 0;
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nxt_rarb_ack = 0;
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else if ((rarb_ack == 0) |
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else if ((rarb_req & rarb_ack) == 0)
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((rarb_req & rarb_ack) == 0))
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begin
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begin
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nxt_ack = 0;
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nxt_rarb_ack = nxt_grant (rarb_ack, rarb_req);
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for (i=`NUM_PORTS; i>0; i=i-1)
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/* -----\/----- EXCLUDED -----\/-----
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if (rarb_req[i-1])
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nxt_ack = 0;
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nxt_ack = i-1;
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for (i=`NUM_PORTS; i>0; i=i-1)
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nxt_rarb_ack = 1 << nxt_ack;
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if (rarb_req[i-1])
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nxt_ack = i-1;
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nxt_rarb_ack = 1 << nxt_ack;
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-----/\----- EXCLUDED -----/\----- */
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end
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end
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end // always @ *
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end // always @ *
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always @(posedge clk)
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always @(posedge clk)
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begin
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begin
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if (reset)
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if (reset)
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rarb_ack <= #1 0;
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rarb_ack <= #1 0;
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else
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else if ((rarb_req & rarb_ack) == 0)
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rarb_ack <= #1 nxt_rarb_ack;
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rarb_ack <= #1 nxt_rarb_ack;
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end
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end
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endmodule // ring_arb
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endmodule // ring_arb
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