a2o/dev/verilog/trilib/tri_regs.v

94 lines
3.5 KiB
Verilog

// © IBM Corp. 2020
// Licensed under the Apache License, Version 2.0 (the "License"), as modified by
// the terms below; you may not use the files in this repository except in
// compliance with the License as modified.
// You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0
//
// Modified Terms:
//
// 1) For the purpose of the patent license granted to you in Section 3 of the
// License, the "Work" hereby includes implementations of the work of authorship
// in physical form.
//
// 2) Notwithstanding any terms to the contrary in the License, any licenses
// necessary for implementation of the Work that are available from OpenPOWER
// via the Power ISA End User License Agreement (EULA) are explicitly excluded
// hereunder, and may be obtained from OpenPOWER under the terms and conditions
// of the EULA.
//
// Unless required by applicable law or agreed to in writing, the reference design
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License
// for the specific language governing permissions and limitations under the License.
//
// Additional rights, including the ability to physically implement a softcore that
// is compliant with the required sections of the Power ISA Specification, are
// available at no cost under the terms of the OpenPOWER Power ISA EULA, which can be
// obtained (along with the Power ISA) here: https://openpowerfoundation.org.
`timescale 1 ns / 1 ns
// *!****************************************************************
// *! FILENAME : tri_regs.v
// *! DESCRIPTION : Multi-bit scan-only latch, LCB included
// *!****************************************************************
`include "tri_a2o.vh"
module tri_regs (
vd,
gd,
clk,
rst,
force_t,
thold_b,
delay_lclkr,
scin,
scout,
dout
);
parameter WIDTH = 4;
parameter OFFSET = 0; //starting bit
parameter INIT = 0; // will be converted to the least signficant
// 31 bits of init_v
parameter IBUF = 1'b0; //inverted latch IOs, if set to true.
parameter DUALSCAN = ""; // if "S", marks data ports as scan for Moebius
parameter NEEDS_SRESET = 1; // for inferred latches
parameter DOMAIN_CROSSING = 0;
inout vd;
inout gd;
input clk;
input rst;
input force_t; // 1: force LCB active
input thold_b; // 1: functional, 0: no clock
input delay_lclkr; // 0: functional
input [OFFSET:OFFSET+WIDTH-1] scin; // scan in
output [OFFSET:OFFSET+WIDTH-1] scout;
output [OFFSET:OFFSET+WIDTH-1] dout;
parameter [0:WIDTH-1] init_v = INIT;
generate
wire sreset;
reg [0:WIDTH-1] int_dout;
(* analysis_not_referenced="true" *)
wire unused;
assign sreset = (NEEDS_SRESET == 1) ? rst : 0;
always @(posedge clk) begin: l
if (sreset)
int_dout <= init_v;
end
assign dout = (IBUF == 1'b1) ? ~int_dout : int_dout;
assign scout = {WIDTH{1'b0}};
assign unused = |{vd, gd, delay_lclkr, scin};
endgenerate
endmodule