From f04a393d48266f5d3e4f35aaddf12ab3214ae8b4 Mon Sep 17 00:00:00 2001 From: Matt Ettus Date: Wed, 16 Mar 2011 16:48:16 -0700 Subject: u1p: use icarus verilog to find warnings --- usrp2/models/FIFO_GENERATOR_V6_1.v | 4575 ++++++++++++++++++++++++++++++++++++ 1 file changed, 4575 insertions(+) create mode 100644 usrp2/models/FIFO_GENERATOR_V6_1.v (limited to 'usrp2/models') diff --git a/usrp2/models/FIFO_GENERATOR_V6_1.v b/usrp2/models/FIFO_GENERATOR_V6_1.v new file mode 100644 index 000000000..65bbac447 --- /dev/null +++ b/usrp2/models/FIFO_GENERATOR_V6_1.v @@ -0,0 +1,4575 @@ +/* + ******************************************************************************* + * + * FIFO Generator - Verilog Behavioral Model + * + ******************************************************************************* + * + * (c) Copyright 1995 - 2009 Xilinx, Inc. All rights reserved. + * + * This file contains confidential and proprietary information + * of Xilinx, Inc. and is protected under U.S. and + * international copyright and other intellectual property + * laws. + * + * DISCLAIMER + * This disclaimer is not a license and does not grant any + * rights to the materials distributed herewith. Except as + * otherwise provided in a valid license issued to you by + * Xilinx, and to the maximum extent permitted by applicable + * law: (1) THESE MATERIALS ARE MADE AVAILABLE "AS IS" AND + * WITH ALL FAULTS, AND XILINX HEREBY DISCLAIMS ALL WARRANTIES + * AND CONDITIONS, EXPRESS, IMPLIED, OR STATUTORY, INCLUDING + * BUT NOT LIMITED TO WARRANTIES OF MERCHANTABILITY, NON- + * INFRINGEMENT, OR FITNESS FOR ANY PARTICULAR PURPOSE; and + * (2) Xilinx shall not be liable (whether in contract or tort, + * including negligence, or under any other theory of + * liability) for any loss or damage of any kind or nature + * related to, arising under or in connection with these + * materials, including for any direct, or any indirect, + * special, incidental, or consequential loss or damage + * (including loss of data, profits, goodwill, or any type of + * loss or damage suffered as a result of any action brought + * by a third party) even if such damage or loss was + * reasonably foreseeable or Xilinx had been advised of the + * possibility of the same. + * + * CRITICAL APPLICATIONS + * Xilinx products are not designed or intended to be fail- + * safe, or for use in any application requiring fail-safe + * performance, such as life-support or safety devices or + * systems, Class III medical devices, nuclear facilities, + * applications related to the deployment of airbags, or any + * other applications that could lead to death, personal + * injury, or severe property or environmental damage + * (individually and collectively, "Critical + * Applications"). Customer assumes the sole risk and + * liability of any use of Xilinx products in Critical + * Applications, subject only to applicable laws and + * regulations governing limitations on product liability. + * + * THIS COPYRIGHT NOTICE AND DISCLAIMER MUST BE RETAINED AS + * PART OF THIS FILE AT ALL TIMES. + * + ******************************************************************************* + ******************************************************************************* + * + * Filename: FIFO_GENERATOR_V6_1.v + * + * Author : Xilinx + * + ******************************************************************************* + * Structure: + * + * fifo_generator_v6_1.vhd + * | + * +-fifo_generator_v6_1_bhv_ver_as + * | + * +-fifo_generator_v6_1_bhv_ver_ss + * | + * +-fifo_generator_v6_1_bhv_ver_preload0 + * + ******************************************************************************* + * Description: + * + * The Verilog behavioral model for the FIFO Generator. + * + * The behavioral model has three parts: + * - The behavioral model for independent clocks FIFOs (_as) + * - The behavioral model for common clock FIFOs (_ss) + * - The "preload logic" block which implements First-word Fall-through + * + ******************************************************************************* + * Description: + * The verilog behavioral model for the FIFO generator core. + * + ******************************************************************************* + */ + +`timescale 1ps/1ps +`ifndef TCQ + `define TCQ 100 +`endif + + +/******************************************************************************* + * Declaration of top-level module + ******************************************************************************/ +module FIFO_GENERATOR_V6_1 + #( + parameter C_COMMON_CLOCK = 0, + parameter C_COUNT_TYPE = 0, + parameter C_DATA_COUNT_WIDTH = 2, + parameter C_DEFAULT_VALUE = "", + parameter C_DIN_WIDTH = 8, + parameter C_DOUT_RST_VAL = "", + parameter C_DOUT_WIDTH = 8, + parameter C_ENABLE_RLOCS = 0, + parameter C_FAMILY = "virtex6", //Not allowed in Verilog model + parameter C_FULL_FLAGS_RST_VAL = 1, + parameter C_HAS_ALMOST_EMPTY = 0, + parameter C_HAS_ALMOST_FULL = 0, + parameter C_HAS_BACKUP = 0, + parameter C_HAS_DATA_COUNT = 0, + parameter C_HAS_INT_CLK = 0, + parameter C_HAS_MEMINIT_FILE = 0, + parameter C_HAS_OVERFLOW = 0, + parameter C_HAS_RD_DATA_COUNT = 0, + parameter C_HAS_RD_RST = 0, + parameter C_HAS_RST = 0, + parameter C_HAS_SRST = 0, + parameter C_HAS_UNDERFLOW = 0, + parameter C_HAS_VALID = 0, + parameter C_HAS_WR_ACK = 0, + parameter C_HAS_WR_DATA_COUNT = 0, + parameter C_HAS_WR_RST = 0, + parameter C_IMPLEMENTATION_TYPE = 0, + parameter C_INIT_WR_PNTR_VAL = 0, + parameter C_MEMORY_TYPE = 1, + parameter C_MIF_FILE_NAME = "", + parameter C_OPTIMIZATION_MODE = 0, + parameter C_OVERFLOW_LOW = 0, + parameter C_PRELOAD_LATENCY = 1, + parameter C_PRELOAD_REGS = 0, + parameter C_PRIM_FIFO_TYPE = "", + parameter C_PROG_EMPTY_THRESH_ASSERT_VAL = 0, + parameter C_PROG_EMPTY_THRESH_NEGATE_VAL = 0, + parameter C_PROG_EMPTY_TYPE = 0, + parameter C_PROG_FULL_THRESH_ASSERT_VAL = 0, + parameter C_PROG_FULL_THRESH_NEGATE_VAL = 0, + parameter C_PROG_FULL_TYPE = 0, + parameter C_RD_DATA_COUNT_WIDTH = 2, + parameter C_RD_DEPTH = 256, + parameter C_RD_FREQ = 1, + parameter C_RD_PNTR_WIDTH = 8, + parameter C_UNDERFLOW_LOW = 0, + parameter C_USE_DOUT_RST = 0, + parameter C_USE_ECC = 0, + parameter C_USE_EMBEDDED_REG = 0, + parameter C_USE_FIFO16_FLAGS = 0, + parameter C_USE_FWFT_DATA_COUNT = 0, + parameter C_VALID_LOW = 0, + parameter C_WR_ACK_LOW = 0, + parameter C_WR_DATA_COUNT_WIDTH = 2, + parameter C_WR_DEPTH = 256, + parameter C_WR_FREQ = 1, + parameter C_WR_PNTR_WIDTH = 8, + parameter C_WR_RESPONSE_LATENCY = 1, + parameter C_MSGON_VAL = 1, + parameter C_ENABLE_RST_SYNC = 1, + parameter C_ERROR_INJECTION_TYPE = 0 + ) + + ( + input BACKUP, + input BACKUP_MARKER, + input CLK, + input RST, + input SRST, + input WR_CLK, + input WR_RST, + input RD_CLK, + input RD_RST, + input [C_DIN_WIDTH-1:0] DIN, + input WR_EN, + input RD_EN, + input [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH, + input [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_ASSERT, + input [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_NEGATE, + input [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH, + input [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_ASSERT, + input [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_NEGATE, + input INT_CLK, + input INJECTDBITERR, + input INJECTSBITERR, + + output [C_DOUT_WIDTH-1:0] DOUT, + output FULL, + output ALMOST_FULL, + output WR_ACK, + output OVERFLOW, + output EMPTY, + output ALMOST_EMPTY, + output VALID, + output UNDERFLOW, + output [C_DATA_COUNT_WIDTH-1:0] DATA_COUNT, + output [C_RD_DATA_COUNT_WIDTH-1:0] RD_DATA_COUNT, + output [C_WR_DATA_COUNT_WIDTH-1:0] WR_DATA_COUNT, + output PROG_FULL, + output PROG_EMPTY, + output SBITERR, + output DBITERR + ); + +/* + ****************************************************************************** + * Definition of Parameters + ****************************************************************************** + * C_COMMON_CLOCK : Common Clock (1), Independent Clocks (0) + * C_COUNT_TYPE : *not used + * C_DATA_COUNT_WIDTH : Width of DATA_COUNT bus + * C_DEFAULT_VALUE : *not used + * C_DIN_WIDTH : Width of DIN bus + * C_DOUT_RST_VAL : Reset value of DOUT + * C_DOUT_WIDTH : Width of DOUT bus + * C_ENABLE_RLOCS : *not used + * C_FAMILY : not used in bhv model + * C_FULL_FLAGS_RST_VAL : Full flags rst val (0 or 1) + * C_HAS_ALMOST_EMPTY : 1=Core has ALMOST_EMPTY flag + * C_HAS_ALMOST_FULL : 1=Core has ALMOST_FULL flag + * C_HAS_BACKUP : *not used + * C_HAS_DATA_COUNT : 1=Core has DATA_COUNT bus + * C_HAS_INT_CLK : not used in bhv model + * C_HAS_MEMINIT_FILE : *not used + * C_HAS_OVERFLOW : 1=Core has OVERFLOW flag + * C_HAS_RD_DATA_COUNT : 1=Core has RD_DATA_COUNT bus + * C_HAS_RD_RST : *not used + * C_HAS_RST : 1=Core has Async Rst + * C_HAS_SRST : 1=Core has Sync Rst + * C_HAS_UNDERFLOW : 1=Core has UNDERFLOW flag + * C_HAS_VALID : 1=Core has VALID flag + * C_HAS_WR_ACK : 1=Core has WR_ACK flag + * C_HAS_WR_DATA_COUNT : 1=Core has WR_DATA_COUNT bus + * C_HAS_WR_RST : *not used + * C_IMPLEMENTATION_TYPE : 0=Common-Clock Bram/Dram + * 1=Common-Clock ShiftRam + * 2=Indep. Clocks Bram/Dram + * 3=Virtex-4 Built-in + * 4=Virtex-5 Built-in + * C_INIT_WR_PNTR_VAL : *not used + * C_MEMORY_TYPE : 1=Block RAM + * 2=Distributed RAM + * 3=Shift RAM + * 4=Built-in FIFO + * C_MIF_FILE_NAME : *not used + * C_OPTIMIZATION_MODE : *not used + * C_OVERFLOW_LOW : 1=OVERFLOW active low + * C_PRELOAD_LATENCY : Latency of read: 0, 1, 2 + * C_PRELOAD_REGS : 1=Use output registers + * C_PRIM_FIFO_TYPE : not used in bhv model + * C_PROG_EMPTY_THRESH_ASSERT_VAL: PROG_EMPTY assert threshold + * C_PROG_EMPTY_THRESH_NEGATE_VAL: PROG_EMPTY negate threshold + * C_PROG_EMPTY_TYPE : 0=No programmable empty + * 1=Single prog empty thresh constant + * 2=Multiple prog empty thresh constants + * 3=Single prog empty thresh input + * 4=Multiple prog empty thresh inputs + * C_PROG_FULL_THRESH_ASSERT_VAL : PROG_FULL assert threshold + * C_PROG_FULL_THRESH_NEGATE_VAL : PROG_FULL negate threshold + * C_PROG_FULL_TYPE : 0=No prog full + * 1=Single prog full thresh constant + * 2=Multiple prog full thresh constants + * 3=Single prog full thresh input + * 4=Multiple prog full thresh inputs + * C_RD_DATA_COUNT_WIDTH : Width of RD_DATA_COUNT bus + * C_RD_DEPTH : Depth of read interface (2^N) + * C_RD_FREQ : not used in bhv model + * C_RD_PNTR_WIDTH : always log2(C_RD_DEPTH) + * C_UNDERFLOW_LOW : 1=UNDERFLOW active low + * C_USE_DOUT_RST : 1=Resets DOUT on RST + * C_USE_ECC : Used for error injection purpose + * C_USE_EMBEDDED_REG : 1=Use BRAM embedded output register + * C_USE_FIFO16_FLAGS : not used in bhv model + * C_USE_FWFT_DATA_COUNT : 1=Use extra logic for FWFT data count + * C_VALID_LOW : 1=VALID active low + * C_WR_ACK_LOW : 1=WR_ACK active low + * C_WR_DATA_COUNT_WIDTH : Width of WR_DATA_COUNT bus + * C_WR_DEPTH : Depth of write interface (2^N) + * C_WR_FREQ : not used in bhv model + * C_WR_PNTR_WIDTH : always log2(C_WR_DEPTH) + * C_WR_RESPONSE_LATENCY : *not used + * C_MSGON_VAL : *not used by bhv model + * C_ENABLE_RST_SYNC : 0 = Use WR_RST & RD_RST + * 1 = Use RST + * C_ERROR_INJECTION_TYPE : 0 = No error injection + * 1 = Single bit error injection only + * 2 = Double bit error injection only + * 3 = Single and double bit error injection + ****************************************************************************** + * Definition of Ports + ****************************************************************************** + * BACKUP : Not used + * BACKUP_MARKER: Not used + * CLK : Clock + * DIN : Input data bus + * PROG_EMPTY_THRESH : Threshold for Programmable Empty Flag + * PROG_EMPTY_THRESH_ASSERT: Threshold for Programmable Empty Flag + * PROG_EMPTY_THRESH_NEGATE: Threshold for Programmable Empty Flag + * PROG_FULL_THRESH : Threshold for Programmable Full Flag + * PROG_FULL_THRESH_ASSERT : Threshold for Programmable Full Flag + * PROG_FULL_THRESH_NEGATE : Threshold for Programmable Full Flag + * RD_CLK : Read Domain Clock + * RD_EN : Read enable + * RD_RST : Read Reset + * RST : Asynchronous Reset + * SRST : Synchronous Reset + * WR_CLK : Write Domain Clock + * WR_EN : Write enable + * WR_RST : Write Reset + * INT_CLK : Internal Clock + * INJECTSBITERR: Inject Signle bit error + * INJECTDBITERR: Inject Double bit error + * ALMOST_EMPTY : One word remaining in FIFO + * ALMOST_FULL : One empty space remaining in FIFO + * DATA_COUNT : Number of data words in fifo( synchronous to CLK) + * DOUT : Output data bus + * EMPTY : Empty flag + * FULL : Full flag + * OVERFLOW : Last write rejected + * PROG_EMPTY : Programmable Empty Flag + * PROG_FULL : Programmable Full Flag + * RD_DATA_COUNT: Number of data words in fifo (synchronous to RD_CLK) + * UNDERFLOW : Last read rejected + * VALID : Last read acknowledged, DOUT bus VALID + * WR_ACK : Last write acknowledged + * WR_DATA_COUNT: Number of data words in fifo (synchronous to WR_CLK) + * SBITERR : Single Bit ECC Error Detected + * DBITERR : Double Bit ECC Error Detected + ****************************************************************************** + */ + + + /***************************************************************************** + * Derived parameters + ****************************************************************************/ + //There are 2 Verilog behavioral models + // 0 = Common-Clock FIFO/ShiftRam FIFO + // 1 = Independent Clocks FIFO + parameter C_VERILOG_IMPL = (C_IMPLEMENTATION_TYPE == 2) ? 1 : 0; + + //Internal reset signals + reg rd_rst_asreg = 0; + reg rd_rst_asreg_d1 = 0; + reg rd_rst_asreg_d2 = 0; + reg rd_rst_reg = 0; + wire rd_rst_comb; + reg rd_rst_d1 = 0; + reg wr_rst_asreg = 0; + reg wr_rst_asreg_d1 = 0; + reg wr_rst_asreg_d2 = 0; + reg wr_rst_reg = 0; + wire wr_rst_comb; + wire wr_rst_i; + wire rd_rst_i; + wire rst_i; + + //Internal reset signals + reg rst_asreg = 0; + reg rst_asreg_d1 = 0; + reg rst_asreg_d2 = 0; + reg rst_reg = 0; + wire rst_comb; + wire rst_full_gen_i; + wire rst_full_ff_i; + + wire RD_CLK_P0_IN; + wire RST_P0_IN; + wire RD_EN_FIFO_IN; + wire RD_EN_P0_IN; + + wire ALMOST_EMPTY_FIFO_OUT; + wire ALMOST_FULL_FIFO_OUT; + wire [C_DATA_COUNT_WIDTH-1:0] DATA_COUNT_FIFO_OUT; + wire [C_DOUT_WIDTH-1:0] DOUT_FIFO_OUT; + wire EMPTY_FIFO_OUT; + wire FULL_FIFO_OUT; + wire OVERFLOW_FIFO_OUT; + wire PROG_EMPTY_FIFO_OUT; + wire PROG_FULL_FIFO_OUT; + wire VALID_FIFO_OUT; + wire [C_RD_DATA_COUNT_WIDTH-1:0] RD_DATA_COUNT_FIFO_OUT; + wire UNDERFLOW_FIFO_OUT; + wire WR_ACK_FIFO_OUT; + wire [C_WR_DATA_COUNT_WIDTH-1:0] WR_DATA_COUNT_FIFO_OUT; + + + //*************************************************************************** + // Internal Signals + // The core uses either the internal_ wires or the preload0_ wires depending + // on whether the core uses Preload0 or not. + // When using preload0, the internal signals connect the internal core to + // the preload logic, and the external core's interfaces are tied to the + // preload0 signals from the preload logic. + //*************************************************************************** + wire [C_DOUT_WIDTH-1:0] DATA_P0_OUT; + wire VALID_P0_OUT; + wire EMPTY_P0_OUT; + wire ALMOSTEMPTY_P0_OUT; + reg EMPTY_P0_OUT_Q; + reg ALMOSTEMPTY_P0_OUT_Q; + wire UNDERFLOW_P0_OUT; + wire RDEN_P0_OUT; + wire [C_DOUT_WIDTH-1:0] DATA_P0_IN; + wire EMPTY_P0_IN; + reg [31:0] DATA_COUNT_FWFT; + reg SS_FWFT_WR ; + reg SS_FWFT_RD ; + + wire sbiterr_fifo_out; + wire dbiterr_fifo_out; + + // Assign 0 if not selected to avoid 'X' propogation to S/DBITERR. + assign inject_sbit_err = ((C_ERROR_INJECTION_TYPE == 1) || (C_ERROR_INJECTION_TYPE == 3)) ? + INJECTSBITERR : 0; + assign inject_dbit_err = ((C_ERROR_INJECTION_TYPE == 2) || (C_ERROR_INJECTION_TYPE == 3)) ? + INJECTDBITERR : 0; + + +// Choose the behavioral model to instantiate based on the C_VERILOG_IMPL +// parameter (1=Independent Clocks, 0=Common Clock) + + localparam FULL_FLAGS_RST_VAL = (C_HAS_SRST == 1) ? 0 : C_FULL_FLAGS_RST_VAL; +generate +case (C_VERILOG_IMPL) +0 : begin : block1 + //Common Clock Behavioral Model + fifo_generator_v6_1_bhv_ver_ss + #( + C_DATA_COUNT_WIDTH, + C_DIN_WIDTH, + C_DOUT_RST_VAL, + C_DOUT_WIDTH, +// C_FULL_FLAGS_RST_VAL, + FULL_FLAGS_RST_VAL, + C_HAS_ALMOST_EMPTY, + C_HAS_ALMOST_FULL, + C_HAS_DATA_COUNT, + C_HAS_OVERFLOW, + C_HAS_RD_DATA_COUNT, + C_HAS_RST, + C_HAS_SRST, + C_HAS_UNDERFLOW, + C_HAS_VALID, + C_HAS_WR_ACK, + C_HAS_WR_DATA_COUNT, + C_IMPLEMENTATION_TYPE, + C_MEMORY_TYPE, + C_OVERFLOW_LOW, + C_PRELOAD_LATENCY, + C_PRELOAD_REGS, + C_PROG_EMPTY_THRESH_ASSERT_VAL, + C_PROG_EMPTY_THRESH_NEGATE_VAL, + C_PROG_EMPTY_TYPE, + C_PROG_FULL_THRESH_ASSERT_VAL, + C_PROG_FULL_THRESH_NEGATE_VAL, + C_PROG_FULL_TYPE, + C_RD_DATA_COUNT_WIDTH, + C_RD_DEPTH, + C_RD_PNTR_WIDTH, + C_UNDERFLOW_LOW, + C_USE_DOUT_RST, + C_USE_EMBEDDED_REG, + C_USE_FWFT_DATA_COUNT, + C_VALID_LOW, + C_WR_ACK_LOW, + C_WR_DATA_COUNT_WIDTH, + C_WR_DEPTH, + C_WR_PNTR_WIDTH, + C_USE_ECC, + C_ENABLE_RST_SYNC, + C_ERROR_INJECTION_TYPE + ) + gen_ss + ( + .CLK (CLK), + .RST (rst_i), + .SRST (SRST), + .RST_FULL_GEN (rst_full_gen_i), + .RST_FULL_FF (rst_full_ff_i), + .DIN (DIN), + .WR_EN (WR_EN), + .RD_EN (RD_EN_FIFO_IN), + .PROG_EMPTY_THRESH (PROG_EMPTY_THRESH), + .PROG_EMPTY_THRESH_ASSERT (PROG_EMPTY_THRESH_ASSERT), + .PROG_EMPTY_THRESH_NEGATE (PROG_EMPTY_THRESH_NEGATE), + .PROG_FULL_THRESH (PROG_FULL_THRESH), + .PROG_FULL_THRESH_ASSERT (PROG_FULL_THRESH_ASSERT), + .PROG_FULL_THRESH_NEGATE (PROG_FULL_THRESH_NEGATE), + .INJECTSBITERR (inject_sbit_err), + .INJECTDBITERR (inject_dbit_err), + .DOUT (DOUT_FIFO_OUT), + .FULL (FULL_FIFO_OUT), + .ALMOST_FULL (ALMOST_FULL_FIFO_OUT), + .WR_ACK (WR_ACK_FIFO_OUT), + .OVERFLOW (OVERFLOW_FIFO_OUT), + .EMPTY (EMPTY_FIFO_OUT), + .ALMOST_EMPTY (ALMOST_EMPTY_FIFO_OUT), + .VALID (VALID_FIFO_OUT), + .UNDERFLOW (UNDERFLOW_FIFO_OUT), + .DATA_COUNT (DATA_COUNT_FIFO_OUT), + .PROG_FULL (PROG_FULL_FIFO_OUT), + .PROG_EMPTY (PROG_EMPTY_FIFO_OUT), + .SBITERR (sbiterr_fifo_out), + .DBITERR (dbiterr_fifo_out) + ); +end +1 : begin : block1 + //Independent Clocks Behavioral Model + fifo_generator_v6_1_bhv_ver_as + #( + C_DATA_COUNT_WIDTH, + C_DIN_WIDTH, + C_DOUT_RST_VAL, + C_DOUT_WIDTH, + C_FULL_FLAGS_RST_VAL, + C_HAS_ALMOST_EMPTY, + C_HAS_ALMOST_FULL, + C_HAS_DATA_COUNT, + C_HAS_OVERFLOW, + C_HAS_RD_DATA_COUNT, + C_HAS_RST, + C_HAS_UNDERFLOW, + C_HAS_VALID, + C_HAS_WR_ACK, + C_HAS_WR_DATA_COUNT, + C_IMPLEMENTATION_TYPE, + C_MEMORY_TYPE, + C_OVERFLOW_LOW, + C_PRELOAD_LATENCY, + C_PRELOAD_REGS, + C_PROG_EMPTY_THRESH_ASSERT_VAL, + C_PROG_EMPTY_THRESH_NEGATE_VAL, + C_PROG_EMPTY_TYPE, + C_PROG_FULL_THRESH_ASSERT_VAL, + C_PROG_FULL_THRESH_NEGATE_VAL, + C_PROG_FULL_TYPE, + C_RD_DATA_COUNT_WIDTH, + C_RD_DEPTH, + C_RD_PNTR_WIDTH, + C_UNDERFLOW_LOW, + C_USE_DOUT_RST, + C_USE_EMBEDDED_REG, + C_USE_FWFT_DATA_COUNT, + C_VALID_LOW, + C_WR_ACK_LOW, + C_WR_DATA_COUNT_WIDTH, + C_WR_DEPTH, + C_WR_PNTR_WIDTH, + C_USE_ECC, + C_ENABLE_RST_SYNC, + C_ERROR_INJECTION_TYPE + ) + gen_as + ( + .WR_CLK (WR_CLK), + .RD_CLK (RD_CLK), + .RST (rst_i), + .RST_FULL_GEN (rst_full_gen_i), + .RST_FULL_FF (rst_full_ff_i), + .WR_RST (wr_rst_i), + .RD_RST (rd_rst_i), + .DIN (DIN), + .WR_EN (WR_EN), + .RD_EN (RD_EN_FIFO_IN), + .RD_EN_USER (RD_EN), + .PROG_EMPTY_THRESH (PROG_EMPTY_THRESH), + .PROG_EMPTY_THRESH_ASSERT (PROG_EMPTY_THRESH_ASSERT), + .PROG_EMPTY_THRESH_NEGATE (PROG_EMPTY_THRESH_NEGATE), + .PROG_FULL_THRESH (PROG_FULL_THRESH), + .PROG_FULL_THRESH_ASSERT (PROG_FULL_THRESH_ASSERT), + .PROG_FULL_THRESH_NEGATE (PROG_FULL_THRESH_NEGATE), + .INJECTSBITERR (inject_sbit_err), + .INJECTDBITERR (inject_dbit_err), + .USER_EMPTY_FB (EMPTY_P0_OUT), + .DOUT (DOUT_FIFO_OUT), + .FULL (FULL_FIFO_OUT), + .ALMOST_FULL (ALMOST_FULL_FIFO_OUT), + .WR_ACK (WR_ACK_FIFO_OUT), + .OVERFLOW (OVERFLOW_FIFO_OUT), + .EMPTY (EMPTY_FIFO_OUT), + .ALMOST_EMPTY (ALMOST_EMPTY_FIFO_OUT), + .VALID (VALID_FIFO_OUT), + .UNDERFLOW (UNDERFLOW_FIFO_OUT), + .RD_DATA_COUNT (RD_DATA_COUNT_FIFO_OUT), + .WR_DATA_COUNT (WR_DATA_COUNT_FIFO_OUT), + .PROG_FULL (PROG_FULL_FIFO_OUT), + .PROG_EMPTY (PROG_EMPTY_FIFO_OUT), + .SBITERR (sbiterr_fifo_out), + .DBITERR (dbiterr_fifo_out) + ); +end + +default : begin : block1 + //Independent Clocks Behavioral Model + fifo_generator_v6_1_bhv_ver_as + #( + C_DATA_COUNT_WIDTH, + C_DIN_WIDTH, + C_DOUT_RST_VAL, + C_DOUT_WIDTH, + C_FULL_FLAGS_RST_VAL, + C_HAS_ALMOST_EMPTY, + C_HAS_ALMOST_FULL, + C_HAS_DATA_COUNT, + C_HAS_OVERFLOW, + C_HAS_RD_DATA_COUNT, + C_HAS_RST, + C_HAS_UNDERFLOW, + C_HAS_VALID, + C_HAS_WR_ACK, + C_HAS_WR_DATA_COUNT, + C_IMPLEMENTATION_TYPE, + C_MEMORY_TYPE, + C_OVERFLOW_LOW, + C_PRELOAD_LATENCY, + C_PRELOAD_REGS, + C_PROG_EMPTY_THRESH_ASSERT_VAL, + C_PROG_EMPTY_THRESH_NEGATE_VAL, + C_PROG_EMPTY_TYPE, + C_PROG_FULL_THRESH_ASSERT_VAL, + C_PROG_FULL_THRESH_NEGATE_VAL, + C_PROG_FULL_TYPE, + C_RD_DATA_COUNT_WIDTH, + C_RD_DEPTH, + C_RD_PNTR_WIDTH, + C_UNDERFLOW_LOW, + C_USE_DOUT_RST, + C_USE_EMBEDDED_REG, + C_USE_FWFT_DATA_COUNT, + C_VALID_LOW, + C_WR_ACK_LOW, + C_WR_DATA_COUNT_WIDTH, + C_WR_DEPTH, + C_WR_PNTR_WIDTH, + C_USE_ECC, + C_ENABLE_RST_SYNC, + C_ERROR_INJECTION_TYPE + ) + gen_as + ( + .WR_CLK (WR_CLK), + .RD_CLK (RD_CLK), + .RST (rst_i), + .RST_FULL_GEN (rst_full_gen_i), + .RST_FULL_FF (rst_full_ff_i), + .WR_RST (wr_rst_i), + .RD_RST (rd_rst_i), + .DIN (DIN), + .WR_EN (WR_EN), + .RD_EN (RD_EN_FIFO_IN), + .RD_EN_USER (RD_EN), + .PROG_EMPTY_THRESH (PROG_EMPTY_THRESH), + .PROG_EMPTY_THRESH_ASSERT (PROG_EMPTY_THRESH_ASSERT), + .PROG_EMPTY_THRESH_NEGATE (PROG_EMPTY_THRESH_NEGATE), + .PROG_FULL_THRESH (PROG_FULL_THRESH), + .PROG_FULL_THRESH_ASSERT (PROG_FULL_THRESH_ASSERT), + .PROG_FULL_THRESH_NEGATE (PROG_FULL_THRESH_NEGATE), + .INJECTSBITERR (inject_sbit_err), + .INJECTDBITERR (inject_dbit_err), + .USER_EMPTY_FB (EMPTY_P0_OUT), + .DOUT (DOUT_FIFO_OUT), + .FULL (FULL_FIFO_OUT), + .ALMOST_FULL (ALMOST_FULL_FIFO_OUT), + .WR_ACK (WR_ACK_FIFO_OUT), + .OVERFLOW (OVERFLOW_FIFO_OUT), + .EMPTY (EMPTY_FIFO_OUT), + .ALMOST_EMPTY (ALMOST_EMPTY_FIFO_OUT), + .VALID (VALID_FIFO_OUT), + .UNDERFLOW (UNDERFLOW_FIFO_OUT), + .RD_DATA_COUNT (RD_DATA_COUNT_FIFO_OUT), + .WR_DATA_COUNT (WR_DATA_COUNT_FIFO_OUT), + .PROG_FULL (PROG_FULL_FIFO_OUT), + .PROG_EMPTY (PROG_EMPTY_FIFO_OUT), + .SBITERR (sbiterr_fifo_out), + .DBITERR (dbiterr_fifo_out) + ); +end + +endcase +endgenerate + + + //************************************************************************** + // Connect Internal Signals + // (Signals labeled internal_*) + // In the normal case, these signals tie directly to the FIFO's inputs and + // outputs. + // In the case of Preload Latency 0 or 1, there are intermediate + // signals between the internal FIFO and the preload logic. + //************************************************************************** + + + //*********************************************** + // If First-Word Fall-Through, instantiate + // the preload0 (FWFT) module + //*********************************************** + generate + if (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) begin : block2 + + + fifo_generator_v6_1_bhv_ver_preload0 + #( + C_DOUT_RST_VAL, + C_DOUT_WIDTH, + C_HAS_RST, + C_ENABLE_RST_SYNC, + C_HAS_SRST, + C_USE_DOUT_RST, + C_USE_ECC, + C_VALID_LOW, + C_UNDERFLOW_LOW, + C_MEMORY_TYPE + ) + fgpl0 + ( + .RD_CLK (RD_CLK_P0_IN), + .RD_RST (RST_P0_IN), + .SRST (SRST), + .RD_EN (RD_EN_P0_IN), + .FIFOEMPTY (EMPTY_P0_IN), + .FIFODATA (DATA_P0_IN), + .FIFOSBITERR (sbiterr_fifo_out), + .FIFODBITERR (dbiterr_fifo_out), + .USERDATA (DATA_P0_OUT), + .USERVALID (VALID_P0_OUT), + .USEREMPTY (EMPTY_P0_OUT), + .USERALMOSTEMPTY (ALMOSTEMPTY_P0_OUT), + .USERUNDERFLOW (UNDERFLOW_P0_OUT), + .RAMVALID (RAMVALID_P0_OUT), + .FIFORDEN (RDEN_P0_OUT), + .USERSBITERR (SBITERR), + .USERDBITERR (DBITERR) + ); + + + //*********************************************** + // Connect inputs to preload (FWFT) module + //*********************************************** + //Connect the RD_CLK of the Preload (FWFT) module to CLK if we + // have a common-clock FIFO, or RD_CLK if we have an + // independent clock FIFO + assign RD_CLK_P0_IN = ((C_VERILOG_IMPL == 0) ? CLK : RD_CLK); + assign RST_P0_IN = (C_COMMON_CLOCK == 0) ? rd_rst_i : (C_HAS_RST == 1) ? rst_i : 0; + assign RD_EN_P0_IN = RD_EN; + assign EMPTY_P0_IN = EMPTY_FIFO_OUT; + assign DATA_P0_IN = DOUT_FIFO_OUT; + + //*********************************************** + // Connect outputs from preload (FWFT) module + //*********************************************** + assign DOUT = DATA_P0_OUT; + assign VALID = VALID_P0_OUT ; + assign EMPTY = EMPTY_P0_OUT; + assign ALMOST_EMPTY = ALMOSTEMPTY_P0_OUT; + assign UNDERFLOW = UNDERFLOW_P0_OUT ; + + assign RD_EN_FIFO_IN = RDEN_P0_OUT; + + + //*********************************************** + // Create DATA_COUNT from First-Word Fall-Through + // data count + //*********************************************** + assign DATA_COUNT = (C_USE_FWFT_DATA_COUNT == 0)? DATA_COUNT_FIFO_OUT: + (C_DATA_COUNT_WIDTH>C_RD_PNTR_WIDTH) ? DATA_COUNT_FWFT[C_RD_PNTR_WIDTH:0] : + DATA_COUNT_FWFT[C_RD_PNTR_WIDTH:C_RD_PNTR_WIDTH-C_DATA_COUNT_WIDTH+1]; + + //*********************************************** + // Create DATA_COUNT from First-Word Fall-Through + // data count + //*********************************************** + always @ (posedge RD_CLK or posedge RST_P0_IN) begin + if (RST_P0_IN) begin + EMPTY_P0_OUT_Q <= #`TCQ 1; + ALMOSTEMPTY_P0_OUT_Q <= #`TCQ 1; + end else begin + EMPTY_P0_OUT_Q <= #`TCQ EMPTY_P0_OUT; + ALMOSTEMPTY_P0_OUT_Q <= #`TCQ ALMOSTEMPTY_P0_OUT; + end + end //always + + + //*********************************************** + // logic for common-clock data count when FWFT is selected + //*********************************************** + initial begin + SS_FWFT_RD = 1'b0; + DATA_COUNT_FWFT = 0 ; + SS_FWFT_WR = 1'b0 ; + end //initial + + + //*********************************************** + // common-clock data count is implemented as an + // up-down counter. SS_FWFT_WR and SS_FWFT_RD + // are the up/down enables for the counter. + //*********************************************** + always @ (RD_EN or VALID_P0_OUT or WR_EN or FULL_FIFO_OUT) begin + if (C_VALID_LOW == 1) begin + SS_FWFT_RD = RD_EN && ~VALID_P0_OUT ; + end else begin + SS_FWFT_RD = RD_EN && VALID_P0_OUT ; + end + SS_FWFT_WR = (WR_EN && (~FULL_FIFO_OUT)) ; + end + + //*********************************************** + // common-clock data count is implemented as an + // up-down counter for FWFT. This always block + // calculates the counter. + //*********************************************** + always @ (posedge RD_CLK_P0_IN or posedge RST_P0_IN) begin + if (RST_P0_IN) begin + DATA_COUNT_FWFT <= #`TCQ 0; + end else begin + if (SRST && (C_HAS_SRST == 1) ) begin + DATA_COUNT_FWFT <= #`TCQ 0; + end else begin + case ( {SS_FWFT_WR, SS_FWFT_RD}) + 2'b00: DATA_COUNT_FWFT <= #`TCQ DATA_COUNT_FWFT ; + 2'b01: DATA_COUNT_FWFT <= #`TCQ DATA_COUNT_FWFT - 1 ; + 2'b10: DATA_COUNT_FWFT <= #`TCQ DATA_COUNT_FWFT + 1 ; + 2'b11: DATA_COUNT_FWFT <= #`TCQ DATA_COUNT_FWFT ; + endcase + end //if SRST + end //IF RST + end //always + + + end else begin : block2 //if !(C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) + + //*********************************************** + // If NOT First-Word Fall-Through, wire the outputs + // of the internal _ss or _as FIFO directly to the + // output, and do not instantiate the preload0 + // module. + //*********************************************** + + assign RD_CLK_P0_IN = 0; + assign RST_P0_IN = 0; + assign RD_EN_P0_IN = 0; + + assign RD_EN_FIFO_IN = RD_EN; + + assign DOUT = DOUT_FIFO_OUT; + assign DATA_P0_IN = 0; + assign VALID = VALID_FIFO_OUT; + assign EMPTY = EMPTY_FIFO_OUT; + assign ALMOST_EMPTY = ALMOST_EMPTY_FIFO_OUT; + assign EMPTY_P0_IN = 0; + assign UNDERFLOW = UNDERFLOW_FIFO_OUT; + assign DATA_COUNT = DATA_COUNT_FIFO_OUT; + assign SBITERR = sbiterr_fifo_out; + assign DBITERR = dbiterr_fifo_out; + + end //if !(C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) + endgenerate + + + //*********************************************** + // Connect user flags to internal signals + //*********************************************** + + //If we are using extra logic for the FWFT data count, then override the + //RD_DATA_COUNT output when we are EMPTY or ALMOST_EMPTY. + //RD_DATA_COUNT is 0 when EMPTY and 1 when ALMOST_EMPTY. + generate + if (C_USE_FWFT_DATA_COUNT==1 && (C_RD_DATA_COUNT_WIDTH>C_RD_PNTR_WIDTH) ) begin : block3 + assign RD_DATA_COUNT = (EMPTY_P0_OUT_Q | RST_P0_IN) ? 0 : (ALMOSTEMPTY_P0_OUT_Q ? 1 : RD_DATA_COUNT_FIFO_OUT); + end //block3 + endgenerate + + //If we are using extra logic for the FWFT data count, then override the + //RD_DATA_COUNT output when we are EMPTY or ALMOST_EMPTY. + //Due to asymmetric ports, RD_DATA_COUNT is 0 when EMPTY or ALMOST_EMPTY. + generate + if (C_USE_FWFT_DATA_COUNT==1 && (C_RD_DATA_COUNT_WIDTH <=C_RD_PNTR_WIDTH) ) begin : block30 + assign RD_DATA_COUNT = (EMPTY_P0_OUT_Q | RST_P0_IN) ? 0 : (ALMOSTEMPTY_P0_OUT_Q ? 0 : RD_DATA_COUNT_FIFO_OUT); + end //block30 + endgenerate + + //If we are not using extra logic for the FWFT data count, + //then connect RD_DATA_COUNT to the RD_DATA_COUNT from the + //internal FIFO instance + generate + if (C_USE_FWFT_DATA_COUNT==0 ) begin : block31 + assign RD_DATA_COUNT = RD_DATA_COUNT_FIFO_OUT; + end + endgenerate + + //Always connect WR_DATA_COUNT to the WR_DATA_COUNT from the internal + //FIFO instance + generate + if (C_USE_FWFT_DATA_COUNT==1) begin : block4 + assign WR_DATA_COUNT = WR_DATA_COUNT_FIFO_OUT; + end + else begin : block4 + assign WR_DATA_COUNT = WR_DATA_COUNT_FIFO_OUT; + end + endgenerate + + + //Connect other flags to the internal FIFO instance + assign FULL = FULL_FIFO_OUT; + assign ALMOST_FULL = ALMOST_FULL_FIFO_OUT; + assign WR_ACK = WR_ACK_FIFO_OUT; + assign OVERFLOW = OVERFLOW_FIFO_OUT; + assign PROG_FULL = PROG_FULL_FIFO_OUT; + assign PROG_EMPTY = PROG_EMPTY_FIFO_OUT; + + + // if an asynchronous FIFO has been selected, display a message that the FIFO + // will not be cycle-accurate in simulation + initial begin + if (C_IMPLEMENTATION_TYPE == 2) begin + $display("WARNING: Behavioral models for independent clock FIFO configurations are not cycle-accurate. You may wish to choose the structural simulation model instead of the behavioral model. This will ensure accurate behavior and latencies during simulation. You can enable this from CORE Generator by selecting Project -> Project Options -> Generation tab -> Structural Simulation. See the FIFO Generator User Guide for more information."); + end else if (C_MEMORY_TYPE == 4) begin + $display("FAILURE : Behavioral models for Virtex-4, Virtex-5 and Virtex-6 built-in FIFO configurations is currently not supported. Please select the structural simulation model option in CORE Generator. You can enable this in CORE Generator by selecting Project -> Project Options -> Generation tab -> Structural Simulation. See the FIFO Generator User Guide for more information."); + $finish; + end + end //initial + + /************************************************************************** + * Internal reset logic + **************************************************************************/ + assign wr_rst_i = (C_HAS_RST == 1 || C_ENABLE_RST_SYNC == 0) ? wr_rst_reg : 0; + assign rd_rst_i = (C_HAS_RST == 1 || C_ENABLE_RST_SYNC == 0) ? rd_rst_reg : 0; + assign rst_i = C_HAS_RST ? rst_reg : 0; + + wire rst_2_sync; + wire clk_2_sync = (C_COMMON_CLOCK == 1) ? CLK : WR_CLK; + generate + if (C_ENABLE_RST_SYNC == 0) begin : gnrst_sync + always @* begin + wr_rst_reg <= WR_RST; + rd_rst_reg <= RD_RST; + rst_reg <= 1'b0; + end + assign rst_2_sync = WR_RST; + end else if (C_HAS_RST == 1 && C_COMMON_CLOCK == 0) begin : gic_rst + assign wr_rst_comb = !wr_rst_asreg_d2 && wr_rst_asreg; + assign rd_rst_comb = !rd_rst_asreg_d2 && rd_rst_asreg; + assign rst_2_sync = RST; + + always @(posedge WR_CLK or posedge RST) begin + if (RST == 1'b1) begin + wr_rst_asreg <= #`TCQ 1'b1; + end else begin + if (wr_rst_asreg_d1 == 1'b1) begin + wr_rst_asreg <= #`TCQ 1'b0; + end else begin + wr_rst_asreg <= #`TCQ wr_rst_asreg; + end + end + end + + always @(posedge WR_CLK) begin + wr_rst_asreg_d1 <= #`TCQ wr_rst_asreg; + wr_rst_asreg_d2 <= #`TCQ wr_rst_asreg_d1; + end + + always @(posedge WR_CLK or posedge wr_rst_comb) begin + if (wr_rst_comb == 1'b1) begin + wr_rst_reg <= #`TCQ 1'b1; + end else begin + wr_rst_reg <= #`TCQ 1'b0; + end + end + + always @(posedge RD_CLK or posedge RST) begin + if (RST == 1'b1) begin + rd_rst_asreg <= #`TCQ 1'b1; + end else begin + if (rd_rst_asreg_d1 == 1'b1) begin + rd_rst_asreg <= #`TCQ 1'b0; + end else begin + rd_rst_asreg <= #`TCQ rd_rst_asreg; + end + end + end + + always @(posedge RD_CLK) begin + rd_rst_asreg_d1 <= #`TCQ rd_rst_asreg; + rd_rst_asreg_d2 <= #`TCQ rd_rst_asreg_d1; + end + + always @(posedge RD_CLK or posedge rd_rst_comb) begin + if (rd_rst_comb == 1'b1) begin + rd_rst_reg <= #`TCQ 1'b1; + end else begin + rd_rst_reg <= #`TCQ 1'b0; + end + end + end else if (C_HAS_RST == 1 && C_COMMON_CLOCK == 1) begin : gcc_rst + assign rst_comb = !rst_asreg_d2 && rst_asreg; + assign rst_2_sync = RST; + + always @(posedge CLK or posedge RST) begin + if (RST == 1'b1) begin + rst_asreg <= #`TCQ 1'b1; + end else begin + if (rst_asreg_d1 == 1'b1) begin + rst_asreg <= #`TCQ 1'b0; + end else begin + rst_asreg <= #`TCQ rst_asreg; + end + end + end + + always @(posedge CLK) begin + rst_asreg_d1 <= #`TCQ rst_asreg; + rst_asreg_d2 <= #`TCQ rst_asreg_d1; + end + + always @(posedge CLK or posedge rst_comb) begin + if (rst_comb == 1'b1) begin + rst_reg <= #`TCQ 1'b1; + end else begin + rst_reg <= #`TCQ 1'b0; + end + end + end + endgenerate + + reg rst_d1 = 1'b0; + reg rst_d2 = 1'b0; + reg rst_d3 = 1'b0; + reg rst_d4 = 1'b0; + generate + if ((C_HAS_RST == 1 || C_HAS_SRST == 1 || C_ENABLE_RST_SYNC == 0) && C_FULL_FLAGS_RST_VAL == 1) begin : grstd1 + // RST_FULL_GEN replaces the reset falling edge detection used to de-assert + // FULL, ALMOST_FULL & PROG_FULL flags if C_FULL_FLAGS_RST_VAL = 1. + + // RST_FULL_FF goes to the reset pin of the final flop of FULL, ALMOST_FULL & + // PROG_FULL + + always @ (posedge rst_2_sync or posedge clk_2_sync) begin + if (rst_2_sync) begin + rst_d1 <= 1'b1; + rst_d2 <= 1'b1; + rst_d3 <= 1'b1; + rst_d4 <= 1'b0; + end else begin + if (SRST) begin + rst_d1 <= #`TCQ 1'b1; + rst_d2 <= #`TCQ 1'b1; + rst_d3 <= #`TCQ 1'b1; + rst_d4 <= #`TCQ 1'b0; + end else begin + rst_d1 <= #`TCQ 1'b0; + rst_d2 <= #`TCQ rst_d1; + rst_d3 <= #`TCQ rst_d2; + rst_d4 <= #`TCQ rst_d3; + end + end + end + assign rst_full_ff_i = (C_HAS_SRST == 0) ? rst_d2 : 1'b0 ; + assign rst_full_gen_i = rst_d4; + + end else if ((C_HAS_RST == 1 || C_HAS_SRST == 1 || C_ENABLE_RST_SYNC == 0) && C_FULL_FLAGS_RST_VAL == 0) begin : gnrst_full + assign rst_full_gen_i = 1'b0; + assign rst_full_ff_i = (C_COMMON_CLOCK == 0) ? wr_rst_i : rst_i; + end + endgenerate + +endmodule //FIFO_GENERATOR_V6_1 + + + +/******************************************************************************* + * Declaration of Independent-Clocks FIFO Module + ******************************************************************************/ +module fifo_generator_v6_1_bhv_ver_as + + /*************************************************************************** + * Declare user parameters and their defaults + ***************************************************************************/ + #( + parameter C_DATA_COUNT_WIDTH = 2, + parameter C_DIN_WIDTH = 8, + parameter C_DOUT_RST_VAL = "", + parameter C_DOUT_WIDTH = 8, + parameter C_FULL_FLAGS_RST_VAL = 1, + parameter C_HAS_ALMOST_EMPTY = 0, + parameter C_HAS_ALMOST_FULL = 0, + parameter C_HAS_DATA_COUNT = 0, + parameter C_HAS_OVERFLOW = 0, + parameter C_HAS_RD_DATA_COUNT = 0, + parameter C_HAS_RST = 0, + parameter C_HAS_UNDERFLOW = 0, + parameter C_HAS_VALID = 0, + parameter C_HAS_WR_ACK = 0, + parameter C_HAS_WR_DATA_COUNT = 0, + parameter C_IMPLEMENTATION_TYPE = 0, + parameter C_MEMORY_TYPE = 1, + parameter C_OVERFLOW_LOW = 0, + parameter C_PRELOAD_LATENCY = 1, + parameter C_PRELOAD_REGS = 0, + parameter C_PROG_EMPTY_THRESH_ASSERT_VAL = 0, + parameter C_PROG_EMPTY_THRESH_NEGATE_VAL = 0, + parameter C_PROG_EMPTY_TYPE = 0, + parameter C_PROG_FULL_THRESH_ASSERT_VAL = 0, + parameter C_PROG_FULL_THRESH_NEGATE_VAL = 0, + parameter C_PROG_FULL_TYPE = 0, + parameter C_RD_DATA_COUNT_WIDTH = 2, + parameter C_RD_DEPTH = 256, + parameter C_RD_PNTR_WIDTH = 8, + parameter C_UNDERFLOW_LOW = 0, + parameter C_USE_DOUT_RST = 0, + parameter C_USE_EMBEDDED_REG = 0, + parameter C_USE_FWFT_DATA_COUNT = 0, + parameter C_VALID_LOW = 0, + parameter C_WR_ACK_LOW = 0, + parameter C_WR_DATA_COUNT_WIDTH = 2, + parameter C_WR_DEPTH = 256, + parameter C_WR_PNTR_WIDTH = 8, + parameter C_USE_ECC = 0, + parameter C_ENABLE_RST_SYNC = 1, + parameter C_ERROR_INJECTION_TYPE = 0 + ) + + /*************************************************************************** + * Declare Input and Output Ports + ***************************************************************************/ + ( + input [C_DIN_WIDTH-1:0] DIN, + input [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH, + input [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_ASSERT, + input [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_NEGATE, + input [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH, + input [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_ASSERT, + input [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_NEGATE, + input RD_CLK, + input RD_EN, + input RD_EN_USER, + input RST, + input RST_FULL_GEN, + input RST_FULL_FF, + input WR_RST, + input RD_RST, + input WR_CLK, + input WR_EN, + input INJECTDBITERR, + input INJECTSBITERR, + input USER_EMPTY_FB, + output reg ALMOST_EMPTY = 1'b1, + output reg ALMOST_FULL = C_FULL_FLAGS_RST_VAL, + output [C_DOUT_WIDTH-1:0] DOUT, + output reg EMPTY = 1'b1, + output reg FULL = C_FULL_FLAGS_RST_VAL, + output OVERFLOW, + output PROG_EMPTY, + output PROG_FULL, + output VALID, + output [C_RD_DATA_COUNT_WIDTH-1:0] RD_DATA_COUNT, + output UNDERFLOW, + output WR_ACK, + output [C_WR_DATA_COUNT_WIDTH-1:0] WR_DATA_COUNT, + output SBITERR, + output DBITERR + ); + + reg [C_RD_PNTR_WIDTH:0] rd_data_count_int = 0; + reg [C_WR_PNTR_WIDTH:0] wr_data_count_int = 0; + reg [C_WR_PNTR_WIDTH:0] wdc_fwft_ext_as = 0; + + + /*************************************************************************** + * Parameters used as constants + **************************************************************************/ + //When RST is present, set FULL reset value to '1'. + //If core has no RST, make sure FULL powers-on as '0'. + parameter C_DEPTH_RATIO_WR = + (C_WR_DEPTH>C_RD_DEPTH) ? (C_WR_DEPTH/C_RD_DEPTH) : 1; + parameter C_DEPTH_RATIO_RD = + (C_RD_DEPTH>C_WR_DEPTH) ? (C_RD_DEPTH/C_WR_DEPTH) : 1; + parameter C_FIFO_WR_DEPTH = C_WR_DEPTH - 1; + parameter C_FIFO_RD_DEPTH = C_RD_DEPTH - 1; + + // C_DEPTH_RATIO_WR | C_DEPTH_RATIO_RD | C_PNTR_WIDTH | EXTRA_WORDS_DC + // -----------------|------------------|-----------------|--------------- + // 1 | 8 | C_RD_PNTR_WIDTH | 2 + // 1 | 4 | C_RD_PNTR_WIDTH | 2 + // 1 | 2 | C_RD_PNTR_WIDTH | 2 + // 1 | 1 | C_WR_PNTR_WIDTH | 2 + // 2 | 1 | C_WR_PNTR_WIDTH | 4 + // 4 | 1 | C_WR_PNTR_WIDTH | 8 + // 8 | 1 | C_WR_PNTR_WIDTH | 16 + + localparam C_PNTR_WIDTH = (C_WR_PNTR_WIDTH>=C_RD_PNTR_WIDTH) ? C_WR_PNTR_WIDTH : C_RD_PNTR_WIDTH; + wire [C_PNTR_WIDTH:0] EXTRA_WORDS_DC = (C_DEPTH_RATIO_WR == 1) ? 2 : (2 * C_DEPTH_RATIO_WR/C_DEPTH_RATIO_RD); + + parameter [31:0] reads_per_write = C_DIN_WIDTH/C_DOUT_WIDTH; + + parameter [31:0] log2_reads_per_write = log2_val(reads_per_write); + + parameter [31:0] writes_per_read = C_DOUT_WIDTH/C_DIN_WIDTH; + + parameter [31:0] log2_writes_per_read = log2_val(writes_per_read); + + + + /************************************************************************** + * FIFO Contents Tracking and Data Count Calculations + *************************************************************************/ + + // Memory which will be used to simulate a FIFO + reg [C_DIN_WIDTH-1:0] memory[C_WR_DEPTH-1:0]; + // Local parameters used to determine whether to inject ECC error or not + localparam SYMMETRIC_PORT = (C_DIN_WIDTH == C_DOUT_WIDTH) ? 1 : 0; + localparam ERR_INJECTION = (C_ERROR_INJECTION_TYPE != 0) ? 1 : 0; + localparam ENABLE_ERR_INJECTION = C_USE_ECC && SYMMETRIC_PORT && ERR_INJECTION; + // Array that holds the error injection type (single/double bit error) on + // a specific write operation, which is returned on read to corrupt the + // output data. + reg [1:0] ecc_err[C_WR_DEPTH-1:0]; + + //The amount of data stored in the FIFO at any time is given + // by num_wr_bits (in the WR_CLK domain) and num_rd_bits (in the RD_CLK + // domain. + //num_wr_bits is calculated by considering the total words in the FIFO, + // and the state of the read pointer (which may not have yet crossed clock + // domains.) + //num_rd_bits is calculated by considering the total words in the FIFO, + // and the state of the write pointer (which may not have yet crossed clock + // domains.) + reg [31:0] num_wr_bits; + reg [31:0] num_rd_bits; + reg [31:0] next_num_wr_bits; + reg [31:0] next_num_rd_bits; + + //The write pointer - tracks write operations + // (Works opposite to core: wr_ptr is a DOWN counter) + reg [31:0] wr_ptr; + reg [C_WR_PNTR_WIDTH-1:0] wr_pntr = 0; // UP counter: Rolls back to 0 when reaches to max value. + reg [C_WR_PNTR_WIDTH-1:0] wr_pntr_rd1 = 0; + reg [C_WR_PNTR_WIDTH-1:0] wr_pntr_rd2 = 0; + reg [C_WR_PNTR_WIDTH-1:0] wr_pntr_rd3 = 0; + wire [C_RD_PNTR_WIDTH-1:0] adj_wr_pntr_rd; + reg [C_WR_PNTR_WIDTH-1:0] wr_pntr_rd = 0; + wire wr_rst_i = WR_RST; + reg wr_rst_d1 =0; + + //The read pointer - tracks read operations + // (rd_ptr Works opposite to core: rd_ptr is a DOWN counter) + reg [31:0] rd_ptr; + reg [C_RD_PNTR_WIDTH-1:0] rd_pntr = 0; // UP counter: Rolls back to 0 when reaches to max value. + reg [C_RD_PNTR_WIDTH-1:0] rd_pntr_wr1 = 0; + reg [C_RD_PNTR_WIDTH-1:0] rd_pntr_wr2 = 0; + reg [C_RD_PNTR_WIDTH-1:0] rd_pntr_wr3 = 0; + reg [C_RD_PNTR_WIDTH-1:0] rd_pntr_wr4 = 0; + wire [C_WR_PNTR_WIDTH-1:0] adj_rd_pntr_wr; + reg [C_RD_PNTR_WIDTH-1:0] rd_pntr_wr = 0; + wire rd_rst_i = RD_RST; + wire ram_rd_en; + reg ram_rd_en_d1 = 1'b0; + + + // Delayed ram_rd_en is needed only for STD Embedded register option + generate + if (C_PRELOAD_LATENCY == 2) begin : grd_d + always @ (posedge RD_CLK or posedge rd_rst_i) begin + if (rd_rst_i) + ram_rd_en_d1 <= #`TCQ 1'b0; + else + ram_rd_en_d1 <= #`TCQ ram_rd_en; + end + end + endgenerate + + // Write pointer adjustment based on pointers width for EMPTY/ALMOST_EMPTY generation + generate + if (C_RD_PNTR_WIDTH > C_WR_PNTR_WIDTH) begin : rdg // Read depth greater than write depth + assign adj_wr_pntr_rd[C_RD_PNTR_WIDTH-1:C_RD_PNTR_WIDTH-C_WR_PNTR_WIDTH] = wr_pntr_rd; + assign adj_wr_pntr_rd[C_RD_PNTR_WIDTH-C_WR_PNTR_WIDTH-1:0] = 0; + end else begin : rdl // Read depth lesser than or equal to write depth + assign adj_wr_pntr_rd = wr_pntr_rd[C_WR_PNTR_WIDTH-1:C_WR_PNTR_WIDTH-C_RD_PNTR_WIDTH]; + end + endgenerate + + // Generate Empty and Almost Empty + // ram_rd_en used to determine EMPTY should depend on the EMPTY. + assign ram_rd_en = RD_EN & !EMPTY; + assign empty_int = ((adj_wr_pntr_rd == rd_pntr) || (ram_rd_en && (adj_wr_pntr_rd == (rd_pntr+1'h1)))); + assign almost_empty_int = ((adj_wr_pntr_rd == (rd_pntr+1'h1)) || (ram_rd_en && (adj_wr_pntr_rd == (rd_pntr+2'h2)))); + + // Register Empty and Almost Empty + always @ (posedge RD_CLK or posedge rd_rst_i) + begin + if (rd_rst_i) begin + EMPTY <= #`TCQ 1'b1; + ALMOST_EMPTY <= #`TCQ 1'b1; + rd_data_count_int <= #`TCQ {C_RD_PNTR_WIDTH-1{1'b0}}; + end else begin + rd_data_count_int <= #`TCQ {(adj_wr_pntr_rd[C_RD_PNTR_WIDTH-1:0] - rd_pntr[C_RD_PNTR_WIDTH-1:0]), 1'b0}; + + if (empty_int) + EMPTY <= #`TCQ 1'b1; + else + EMPTY <= #`TCQ 1'b0; + + if (!EMPTY) begin + if (almost_empty_int) + ALMOST_EMPTY <= #`TCQ 1'b1; + else + ALMOST_EMPTY <= #`TCQ 1'b0; + end + end // rd_rst_i + end // always + + // Read pointer adjustment based on pointers width for EMPTY/ALMOST_EMPTY generation + generate + if (C_WR_PNTR_WIDTH > C_RD_PNTR_WIDTH) begin : wdg // Write depth greater than read depth + assign adj_rd_pntr_wr[C_WR_PNTR_WIDTH-1:C_WR_PNTR_WIDTH-C_RD_PNTR_WIDTH] = rd_pntr_wr; + assign adj_rd_pntr_wr[C_WR_PNTR_WIDTH-C_RD_PNTR_WIDTH-1:0] = 0; + end else begin : wdl // Write depth lesser than or equal to read depth + assign adj_rd_pntr_wr = rd_pntr_wr[C_RD_PNTR_WIDTH-1:C_RD_PNTR_WIDTH-C_WR_PNTR_WIDTH]; + end + endgenerate + + // Generate FULL and ALMOST_FULL + // ram_wr_en used to determine FULL should depend on the FULL. + assign ram_wr_en = WR_EN & !FULL; + assign full_int = ((adj_rd_pntr_wr == (wr_pntr+1'h1)) || (ram_wr_en && (adj_rd_pntr_wr == (wr_pntr+2'h2)))); + assign almost_full_int = ((adj_rd_pntr_wr == (wr_pntr+2'h2)) || (ram_wr_en && (adj_rd_pntr_wr == (wr_pntr+3'h3)))); + + // Register FULL and ALMOST_FULL Empty + always @ (posedge WR_CLK or posedge RST_FULL_FF) + begin + if (RST_FULL_FF) begin + FULL <= #`TCQ C_FULL_FLAGS_RST_VAL; + ALMOST_FULL <= #`TCQ C_FULL_FLAGS_RST_VAL; + wr_data_count_int <= #`TCQ {C_WR_DATA_COUNT_WIDTH-1{1'b0}}; + end else begin + wr_data_count_int <= #`TCQ {(wr_pntr[C_WR_PNTR_WIDTH-1:0] - adj_rd_pntr_wr[C_WR_PNTR_WIDTH-1:0]), 1'b0}; + if (full_int) begin + FULL <= #`TCQ 1'b1; + end else begin + FULL <= #`TCQ 1'b0; + end + + if (RST_FULL_GEN) begin + ALMOST_FULL <= #`TCQ 1'b0; + end else if (!FULL) begin + if (almost_full_int) + ALMOST_FULL <= #`TCQ 1'b1; + else + ALMOST_FULL <= #`TCQ 1'b0; + end + end // wr_rst_i + end // always + + // Determine which stage in FWFT registers are valid + reg stage1_valid = 0; + reg stage2_valid = 0; + generate + if (C_PRELOAD_LATENCY == 0) begin : grd_fwft_proc + always @ (posedge RD_CLK or posedge rd_rst_i) begin + if (rd_rst_i) begin + stage1_valid <= #`TCQ 0; + stage2_valid <= #`TCQ 0; + end else begin + + if (!stage1_valid && !stage2_valid) begin + if (!EMPTY) + stage1_valid <= #`TCQ 1'b1; + else + stage1_valid <= #`TCQ 1'b0; + end else if (stage1_valid && !stage2_valid) begin + if (EMPTY) begin + stage1_valid <= #`TCQ 1'b0; + stage2_valid <= #`TCQ 1'b1; + end else begin + stage1_valid <= #`TCQ 1'b1; + stage2_valid <= #`TCQ 1'b1; + end + end else if (!stage1_valid && stage2_valid) begin + if (EMPTY && RD_EN_USER) begin + stage1_valid <= #`TCQ 1'b0; + stage2_valid <= #`TCQ 1'b0; + end else if (!EMPTY && RD_EN_USER) begin + stage1_valid <= #`TCQ 1'b1; + stage2_valid <= #`TCQ 1'b0; + end else if (!EMPTY && !RD_EN_USER) begin + stage1_valid <= #`TCQ 1'b1; + stage2_valid <= #`TCQ 1'b1; + end else begin + stage1_valid <= #`TCQ 1'b0; + stage2_valid <= #`TCQ 1'b1; + end + end else if (stage1_valid && stage2_valid) begin + if (EMPTY && RD_EN_USER) begin + stage1_valid <= #`TCQ 1'b0; + stage2_valid <= #`TCQ 1'b1; + end else begin + stage1_valid <= #`TCQ 1'b1; + stage2_valid <= #`TCQ 1'b1; + end + end else begin + stage1_valid <= #`TCQ 1'b0; + stage2_valid <= #`TCQ 1'b0; + end + end // rd_rst_i + end // always + end + endgenerate + + //Pointers passed into opposite clock domain + reg [31:0] wr_ptr_rdclk; + reg [31:0] wr_ptr_rdclk_next; + reg [31:0] rd_ptr_wrclk; + reg [31:0] rd_ptr_wrclk_next; + + //Amount of data stored in the FIFO scaled to the narrowest (deepest) port + // (Do not include data in FWFT stages) + //Used to calculate PROG_EMPTY. + wire [31:0] num_read_words_pe = + num_rd_bits/(C_DOUT_WIDTH/C_DEPTH_RATIO_WR); + + //Amount of data stored in the FIFO scaled to the narrowest (deepest) port + // (Do not include data in FWFT stages) + //Used to calculate PROG_FULL. + wire [31:0] num_write_words_pf = + num_wr_bits/(C_DIN_WIDTH/C_DEPTH_RATIO_RD); + + /************************** + * Read Data Count + *************************/ + + reg [31:0] num_read_words_dc; + reg [C_RD_DATA_COUNT_WIDTH-1:0] num_read_words_sized_i; + + always @(num_rd_bits) begin + if (C_USE_FWFT_DATA_COUNT) begin + + //If using extra logic for FWFT Data Counts, + // then scale FIFO contents to read domain, + // and add two read words for FWFT stages + //This value is only a temporary value and not used in the code. + num_read_words_dc = (num_rd_bits/C_DOUT_WIDTH+2); + + //Trim the read words for use with RD_DATA_COUNT + num_read_words_sized_i = + num_read_words_dc[C_RD_PNTR_WIDTH : C_RD_PNTR_WIDTH-C_RD_DATA_COUNT_WIDTH+1]; + + end else begin + + //If not using extra logic for FWFT Data Counts, + // then scale FIFO contents to read domain. + //This value is only a temporary value and not used in the code. + num_read_words_dc = num_rd_bits/C_DOUT_WIDTH; + + //Trim the read words for use with RD_DATA_COUNT + num_read_words_sized_i = + num_read_words_dc[C_RD_PNTR_WIDTH-1 : C_RD_PNTR_WIDTH-C_RD_DATA_COUNT_WIDTH]; + + end //if (C_USE_FWFT_DATA_COUNT) + end //always + + + /************************** + * Write Data Count + *************************/ + + reg [31:0] num_write_words_dc; + reg [C_WR_DATA_COUNT_WIDTH-1:0] num_write_words_sized_i; + + always @(num_wr_bits) begin + if (C_USE_FWFT_DATA_COUNT) begin + + //Calculate the Data Count value for the number of write words, + // when using First-Word Fall-Through with extra logic for Data + // Counts. This takes into consideration the number of words that + // are expected to be stored in the FWFT register stages (it always + // assumes they are filled). + //This value is scaled to the Write Domain. + //The expression (((A-1)/B))+1 divides A/B, but takes the + // ceiling of the result. + //When num_wr_bits==0, set the result manually to prevent + // division errors. + //EXTRA_WORDS_DC is the number of words added to write_words + // due to FWFT. + //This value is only a temporary value and not used in the code. + num_write_words_dc = (num_wr_bits==0) ? EXTRA_WORDS_DC : (((num_wr_bits-1)/C_DIN_WIDTH)+1) + EXTRA_WORDS_DC ; + + //Trim the write words for use with WR_DATA_COUNT + num_write_words_sized_i = + num_write_words_dc[C_WR_PNTR_WIDTH : C_WR_PNTR_WIDTH-C_WR_DATA_COUNT_WIDTH+1]; + + end else begin + + //Calculate the Data Count value for the number of write words, when NOT + // using First-Word Fall-Through with extra logic for Data Counts. This + // calculates only the number of words in the internal FIFO. + //The expression (((A-1)/B))+1 divides A/B, but takes the + // ceiling of the result. + //This value is scaled to the Write Domain. + //When num_wr_bits==0, set the result manually to prevent + // division errors. + //This value is only a temporary value and not used in the code. + num_write_words_dc = (num_wr_bits==0) ? 0 : ((num_wr_bits-1)/C_DIN_WIDTH)+1; + + //Trim the read words for use with RD_DATA_COUNT + num_write_words_sized_i = + num_write_words_dc[C_WR_PNTR_WIDTH-1 : C_WR_PNTR_WIDTH-C_WR_DATA_COUNT_WIDTH]; + + end //if (C_USE_FWFT_DATA_COUNT) + end //always + + + + /*************************************************************************** + * Internal registers and wires + **************************************************************************/ + + //Temporary signals used for calculating the model's outputs. These + //are only used in the assign statements immediately following wire, + //parameter, and function declarations. + wire [C_DOUT_WIDTH-1:0] ideal_dout_out; + wire valid_i; + wire valid_out; + wire underflow_i; + + //Ideal FIFO signals. These are the raw output of the behavioral model, + //which behaves like an ideal FIFO. + reg [1:0] err_type = 0; + reg [1:0] err_type_d1 = 0; + reg [C_DOUT_WIDTH-1:0] ideal_dout = 0; + reg [C_DOUT_WIDTH-1:0] ideal_dout_d1 = 0; + reg ideal_wr_ack = 0; + reg ideal_valid = 0; + reg ideal_overflow = 0; + reg ideal_underflow = 0; + reg ideal_prog_full = 0; + reg ideal_prog_empty = 1; + reg [C_WR_DATA_COUNT_WIDTH-1 : 0] ideal_wr_count = 0; + reg [C_RD_DATA_COUNT_WIDTH-1 : 0] ideal_rd_count = 0; + + //Assorted reg values for delayed versions of signals + reg valid_d1 = 0; + + + //user specified value for reseting the size of the fifo + reg [C_DOUT_WIDTH-1:0] dout_reset_val = 0; + + //temporary registers for WR_RESPONSE_LATENCY feature + + integer tmp_wr_listsize; + integer tmp_rd_listsize; + + //Signal for registered version of prog full and empty + + //Threshold values for Programmable Flags + integer prog_empty_actual_thresh_assert; + integer prog_empty_actual_thresh_negate; + integer prog_full_actual_thresh_assert; + integer prog_full_actual_thresh_negate; + + + /**************************************************************************** + * Function Declarations + ***************************************************************************/ + + /************************************************************************** + * write_fifo + * This task writes a word to the FIFO memory and updates the + * write pointer. + * FIFO size is relative to write domain. + ***************************************************************************/ + task write_fifo; + begin + memory[wr_ptr] <= DIN; + wr_pntr <= #`TCQ wr_pntr + 1; + // Store the type of error injection (double/single) on write + case (C_ERROR_INJECTION_TYPE) + 3: ecc_err[wr_ptr] <= {INJECTDBITERR,INJECTSBITERR}; + 2: ecc_err[wr_ptr] <= {INJECTDBITERR,1'b0}; + 1: ecc_err[wr_ptr] <= {1'b0,INJECTSBITERR}; + default: ecc_err[wr_ptr] <= 0; + endcase + // (Works opposite to core: wr_ptr is a DOWN counter) + if (wr_ptr == 0) begin + wr_ptr <= C_WR_DEPTH - 1; + end else begin + wr_ptr <= wr_ptr - 1; + end + end + endtask // write_fifo + + /************************************************************************** + * read_fifo + * This task reads a word from the FIFO memory and updates the read + * pointer. It's output is the ideal_dout bus. + * FIFO size is relative to write domain. + ***************************************************************************/ + task read_fifo; + integer i; + reg [C_DOUT_WIDTH-1:0] tmp_dout; + reg [C_DIN_WIDTH-1:0] memory_read; + reg [31:0] tmp_rd_ptr; + reg [31:0] rd_ptr_high; + reg [31:0] rd_ptr_low; + reg [1:0] tmp_ecc_err; + begin + rd_pntr <= #`TCQ rd_pntr + 1; + // output is wider than input + if (reads_per_write == 0) begin + tmp_dout = 0; + tmp_rd_ptr = (rd_ptr << log2_writes_per_read)+(writes_per_read-1); + for (i = writes_per_read - 1; i >= 0; i = i - 1) begin + tmp_dout = tmp_dout << C_DIN_WIDTH; + tmp_dout = tmp_dout | memory[tmp_rd_ptr]; + + // (Works opposite to core: rd_ptr is a DOWN counter) + if (tmp_rd_ptr == 0) begin + tmp_rd_ptr = C_WR_DEPTH - 1; + end else begin + tmp_rd_ptr = tmp_rd_ptr - 1; + end + end + + // output is symmetric + end else if (reads_per_write == 1) begin + tmp_dout = memory[rd_ptr][C_DIN_WIDTH-1:0]; + // Retreive the error injection type. Based on the error injection type + // corrupt the output data. + tmp_ecc_err = ecc_err[rd_ptr]; + if (ENABLE_ERR_INJECTION && C_DIN_WIDTH == C_DOUT_WIDTH) begin + if (tmp_ecc_err[1]) begin // Corrupt the output data only for double bit error + if (C_DOUT_WIDTH == 1) + tmp_dout = tmp_dout[C_DOUT_WIDTH-1:0]; + else if (C_DOUT_WIDTH == 2) + tmp_dout = {~tmp_dout[C_DOUT_WIDTH-1],~tmp_dout[C_DOUT_WIDTH-2]}; + else + tmp_dout = {~tmp_dout[C_DOUT_WIDTH-1],~tmp_dout[C_DOUT_WIDTH-2],(tmp_dout << 2)}; + end else begin + tmp_dout = tmp_dout[C_DOUT_WIDTH-1:0]; + end + err_type <= {tmp_ecc_err[1], tmp_ecc_err[0] & !tmp_ecc_err[1]}; + end else begin + err_type <= 0; + end + + // input is wider than output + end else begin + rd_ptr_high = rd_ptr >> log2_reads_per_write; + rd_ptr_low = rd_ptr & (reads_per_write - 1); + memory_read = memory[rd_ptr_high]; + tmp_dout = memory_read >> (rd_ptr_low*C_DOUT_WIDTH); + end + ideal_dout <= tmp_dout; + + // (Works opposite to core: rd_ptr is a DOWN counter) + if (rd_ptr == 0) begin + rd_ptr <= C_RD_DEPTH - 1; + end else begin + rd_ptr <= rd_ptr - 1; + end + end + endtask + + /************************************************************************** + * log2_val + * Returns the 'log2' value for the input value for the supported ratios + ***************************************************************************/ + function [31:0] log2_val; + input [31:0] binary_val; + + begin + if (binary_val == 8) begin + log2_val = 3; + end else if (binary_val == 4) begin + log2_val = 2; + end else begin + log2_val = 1; + end + end + endfunction + + /*********************************************************************** + * hexstr_conv + * Converts a string of type hex to a binary value (for C_DOUT_RST_VAL) + ***********************************************************************/ + function [C_DOUT_WIDTH-1:0] hexstr_conv; + input [(C_DOUT_WIDTH*8)-1:0] def_data; + + integer index,i,j; + reg [3:0] bin; + + begin + index = 0; + hexstr_conv = 'b0; + for( i=C_DOUT_WIDTH-1; i>=0; i=i-1 ) + begin + case (def_data[7:0]) + 8'b00000000 : + begin + bin = 4'b0000; + i = -1; + end + 8'b00110000 : bin = 4'b0000; + 8'b00110001 : bin = 4'b0001; + 8'b00110010 : bin = 4'b0010; + 8'b00110011 : bin = 4'b0011; + 8'b00110100 : bin = 4'b0100; + 8'b00110101 : bin = 4'b0101; + 8'b00110110 : bin = 4'b0110; + 8'b00110111 : bin = 4'b0111; + 8'b00111000 : bin = 4'b1000; + 8'b00111001 : bin = 4'b1001; + 8'b01000001 : bin = 4'b1010; + 8'b01000010 : bin = 4'b1011; + 8'b01000011 : bin = 4'b1100; + 8'b01000100 : bin = 4'b1101; + 8'b01000101 : bin = 4'b1110; + 8'b01000110 : bin = 4'b1111; + 8'b01100001 : bin = 4'b1010; + 8'b01100010 : bin = 4'b1011; + 8'b01100011 : bin = 4'b1100; + 8'b01100100 : bin = 4'b1101; + 8'b01100101 : bin = 4'b1110; + 8'b01100110 : bin = 4'b1111; + default : + begin + bin = 4'bx; + end + endcase + for( j=0; j<4; j=j+1) + begin + if ((index*4)+j < C_DOUT_WIDTH) + begin + hexstr_conv[(index*4)+j] = bin[j]; + end + end + index = index + 1; + def_data = def_data >> 8; + end + end + endfunction + + /************************************************************************* + * Initialize Signals for clean power-on simulation + *************************************************************************/ + initial begin + num_wr_bits = 0; + num_rd_bits = 0; + next_num_wr_bits = 0; + next_num_rd_bits = 0; + rd_ptr = C_RD_DEPTH - 1; + wr_ptr = C_WR_DEPTH - 1; + wr_pntr = 0; + rd_pntr = 0; + rd_ptr_wrclk = rd_ptr; + wr_ptr_rdclk = wr_ptr; + dout_reset_val = hexstr_conv(C_DOUT_RST_VAL); + ideal_dout = dout_reset_val; + err_type = 0; + ideal_dout_d1 = dout_reset_val; + ideal_wr_ack = 1'b0; + ideal_valid = 1'b0; + valid_d1 = 1'b0; + ideal_overflow = 1'b0; + ideal_underflow = 1'b0; + ideal_wr_count = 0; + ideal_rd_count = 0; + ideal_prog_full = 1'b0; + ideal_prog_empty = 1'b1; + end + + + /************************************************************************* + * Connect the module inputs and outputs to the internal signals of the + * behavioral model. + *************************************************************************/ + //Inputs + /* + wire [C_DIN_WIDTH-1:0] DIN; + wire [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH; + wire [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_ASSERT; + wire [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_NEGATE; + wire [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH; + wire [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_ASSERT; + wire [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_NEGATE; + wire RD_CLK; + wire RD_EN; + wire RST; + wire WR_CLK; + wire WR_EN; + */ + + //*************************************************************************** + // Dout may change behavior based on latency + //*************************************************************************** + assign ideal_dout_out[C_DOUT_WIDTH-1:0] = (C_PRELOAD_LATENCY==2 && + (C_MEMORY_TYPE==0 || C_MEMORY_TYPE==1))? + ideal_dout_d1: ideal_dout; + assign DOUT[C_DOUT_WIDTH-1:0] = ideal_dout_out; + + //*************************************************************************** + // Assign SBITERR and DBITERR based on latency + //*************************************************************************** + assign SBITERR = (C_ERROR_INJECTION_TYPE == 1 || C_ERROR_INJECTION_TYPE == 3) && + (C_PRELOAD_LATENCY == 2 && + (C_MEMORY_TYPE==0 || C_MEMORY_TYPE==1)) ? + err_type_d1[0]: err_type[0]; + assign DBITERR = (C_ERROR_INJECTION_TYPE == 2 || C_ERROR_INJECTION_TYPE == 3) && + (C_PRELOAD_LATENCY==2 && (C_MEMORY_TYPE==0 || C_MEMORY_TYPE==1)) ? + err_type_d1[1]: err_type[1]; + + + //*************************************************************************** + // Overflow may be active-low + //*************************************************************************** + generate + if (C_HAS_OVERFLOW==1) begin : blockOF1 + assign OVERFLOW = ideal_overflow ? !C_OVERFLOW_LOW : C_OVERFLOW_LOW; + end + endgenerate + + assign PROG_EMPTY = ideal_prog_empty; + assign PROG_FULL = ideal_prog_full; + + //*************************************************************************** + // Valid may change behavior based on latency or active-low + //*************************************************************************** + generate + if (C_HAS_VALID==1) begin : blockVL1 + assign valid_i = (C_PRELOAD_LATENCY==0) ? (RD_EN & ~EMPTY) : ideal_valid; + assign valid_out = (C_PRELOAD_LATENCY==2 && + (C_MEMORY_TYPE==0 || C_MEMORY_TYPE==1))? + valid_d1: valid_i; + assign VALID = valid_out ? !C_VALID_LOW : C_VALID_LOW; + end + endgenerate + + + //*************************************************************************** + // Underflow may change behavior based on latency or active-low + //*************************************************************************** + generate + if (C_HAS_UNDERFLOW==1) begin : blockUF1 + assign underflow_i = (C_PRELOAD_LATENCY==0) ? (RD_EN & EMPTY) : ideal_underflow; + assign UNDERFLOW = underflow_i ? !C_UNDERFLOW_LOW : C_UNDERFLOW_LOW; + end + endgenerate + + //*************************************************************************** + // Write acknowledge may be active low + //*************************************************************************** + generate + if (C_HAS_WR_ACK==1) begin : blockWK1 + assign WR_ACK = ideal_wr_ack ? !C_WR_ACK_LOW : C_WR_ACK_LOW; + end + endgenerate + + + //*************************************************************************** + // Generate RD_DATA_COUNT if Use Extra Logic option is selected + //*************************************************************************** + generate + if (C_HAS_WR_DATA_COUNT == 1 && C_USE_FWFT_DATA_COUNT == 1) begin : wdc_fwft_ext + + reg [C_PNTR_WIDTH-1:0] adjusted_wr_pntr = 0; + reg [C_PNTR_WIDTH-1:0] adjusted_rd_pntr = 0; + wire [C_PNTR_WIDTH-1:0] diff_wr_rd_tmp; + wire [C_PNTR_WIDTH:0] diff_wr_rd; + reg [C_PNTR_WIDTH:0] wr_data_count_i = 0; + always @* begin + if (C_WR_PNTR_WIDTH > C_RD_PNTR_WIDTH) begin + adjusted_wr_pntr = wr_pntr; + adjusted_rd_pntr = 0; + adjusted_rd_pntr[C_PNTR_WIDTH-1:C_PNTR_WIDTH-C_RD_PNTR_WIDTH] = rd_pntr_wr; + end else if (C_WR_PNTR_WIDTH < C_RD_PNTR_WIDTH) begin + adjusted_rd_pntr = rd_pntr_wr; + adjusted_wr_pntr = 0; + adjusted_wr_pntr[C_PNTR_WIDTH-1:C_PNTR_WIDTH-C_WR_PNTR_WIDTH] = wr_pntr; + end else begin + adjusted_wr_pntr = wr_pntr; + adjusted_rd_pntr = rd_pntr_wr; + end + end // always @* + + assign diff_wr_rd_tmp = adjusted_wr_pntr - adjusted_rd_pntr; + assign diff_wr_rd = {1'b0,diff_wr_rd_tmp}; + + always @ (posedge wr_rst_i or posedge WR_CLK) + begin + if (wr_rst_i) + wr_data_count_i <= #`TCQ 0; + else + wr_data_count_i <= #`TCQ diff_wr_rd + EXTRA_WORDS_DC; + end // always @ (posedge WR_CLK or posedge WR_CLK) + + always @* begin + if (C_WR_PNTR_WIDTH >= C_RD_PNTR_WIDTH) + wdc_fwft_ext_as = wr_data_count_i[C_PNTR_WIDTH:0]; + else + wdc_fwft_ext_as = wr_data_count_i[C_PNTR_WIDTH:C_RD_PNTR_WIDTH-C_WR_PNTR_WIDTH]; + end // always @* + end // wdc_fwft_ext + endgenerate + + //*************************************************************************** + // Generate RD_DATA_COUNT if Use Extra Logic option is selected + //*************************************************************************** + reg [C_RD_PNTR_WIDTH:0] rdc_fwft_ext_as = 0; + + generate + if (C_HAS_RD_DATA_COUNT == 1 && C_USE_FWFT_DATA_COUNT == 1) begin : rdc_fwft_ext + reg [C_RD_PNTR_WIDTH-1:0] adjusted_wr_pntr_rd = 0; + wire [C_RD_PNTR_WIDTH-1:0] diff_rd_wr_tmp; + wire [C_RD_PNTR_WIDTH:0] diff_rd_wr; + always @* begin + if (C_RD_PNTR_WIDTH > C_WR_PNTR_WIDTH) begin + adjusted_wr_pntr_rd = 0; + adjusted_wr_pntr_rd[C_RD_PNTR_WIDTH-1:C_RD_PNTR_WIDTH-C_WR_PNTR_WIDTH] = wr_pntr_rd; + end else begin + adjusted_wr_pntr_rd = wr_pntr_rd[C_WR_PNTR_WIDTH-1:C_WR_PNTR_WIDTH-C_RD_PNTR_WIDTH]; + end + end // always @* + + assign diff_rd_wr_tmp = adjusted_wr_pntr_rd - rd_pntr; + assign diff_rd_wr = {1'b0,diff_rd_wr_tmp}; + + always @ (posedge rd_rst_i or posedge RD_CLK) + begin + if (rd_rst_i) begin + rdc_fwft_ext_as <= #`TCQ 0; + end else begin + if (!stage2_valid) + rdc_fwft_ext_as <= #`TCQ 0; + else if (!stage1_valid && stage2_valid) + rdc_fwft_ext_as <= #`TCQ 1; + else + rdc_fwft_ext_as <= #`TCQ diff_rd_wr + 2'h2; + end + end // always @ (posedge WR_CLK or posedge WR_CLK) + end // rdc_fwft_ext + endgenerate + + //*************************************************************************** + // Assign the read data count value only if it is selected, + // otherwise output zeros. + //*************************************************************************** + generate + if (C_HAS_RD_DATA_COUNT == 1) begin : grdc + assign RD_DATA_COUNT[C_RD_DATA_COUNT_WIDTH-1:0] = C_USE_FWFT_DATA_COUNT ? + rdc_fwft_ext_as[C_RD_PNTR_WIDTH:C_RD_PNTR_WIDTH+1-C_RD_DATA_COUNT_WIDTH] : + rd_data_count_int[C_RD_PNTR_WIDTH:C_RD_PNTR_WIDTH+1-C_RD_DATA_COUNT_WIDTH]; + end + endgenerate + + generate + if (C_HAS_RD_DATA_COUNT == 0) begin : gnrdc + assign RD_DATA_COUNT[C_RD_DATA_COUNT_WIDTH-1:0] = {C_RD_DATA_COUNT_WIDTH-1{1'b0}}; + end + endgenerate + + //*************************************************************************** + // Assign the write data count value only if it is selected, + // otherwise output zeros + //*************************************************************************** + generate + if (C_HAS_WR_DATA_COUNT == 1) begin : gwdc + assign WR_DATA_COUNT[C_WR_DATA_COUNT_WIDTH-1:0] = (C_USE_FWFT_DATA_COUNT == 1) ? + wdc_fwft_ext_as[C_WR_PNTR_WIDTH:C_WR_PNTR_WIDTH+1-C_WR_DATA_COUNT_WIDTH] : + wr_data_count_int[C_WR_PNTR_WIDTH:C_WR_PNTR_WIDTH+1-C_WR_DATA_COUNT_WIDTH]; + end + endgenerate + + generate + if (C_HAS_WR_DATA_COUNT == 0) begin : gnwdc + assign WR_DATA_COUNT[C_WR_DATA_COUNT_WIDTH-1:0] = {C_WR_DATA_COUNT_WIDTH-1{1'b0}}; + end + endgenerate + + + /************************************************************************** + * Assorted registers for delayed versions of signals + **************************************************************************/ + //Capture delayed version of valid + generate + if (C_HAS_VALID==1) begin : blockVL2 + always @(posedge RD_CLK or posedge rd_rst_i) begin + if (rd_rst_i == 1'b1) begin + valid_d1 <= #`TCQ 1'b0; + end else begin + valid_d1 <= #`TCQ valid_i; + end + end + end + endgenerate + + //Capture delayed version of dout + always @(posedge RD_CLK or posedge rd_rst_i) begin + if (rd_rst_i == 1'b1) begin + // Reset err_type only if ECC is not selected + if (C_USE_ECC == 0) + err_type_d1 <= #`TCQ 0; + end else if (ram_rd_en_d1) begin + ideal_dout_d1 <= #`TCQ ideal_dout; + err_type_d1 <= #`TCQ err_type; + end + end + + /************************************************************************** + * Overflow and Underflow Flag calculation + * (handled separately because they don't support rst) + **************************************************************************/ + generate + if (C_HAS_OVERFLOW==1) begin : blockOF2 + always @(posedge WR_CLK) begin + ideal_overflow <= #`TCQ WR_EN & FULL; + end + end + endgenerate + + generate + if (C_HAS_UNDERFLOW==1) begin : blockUF2 + always @(posedge RD_CLK) begin + ideal_underflow <= #`TCQ EMPTY & RD_EN; + end + end + endgenerate + + /************************************************************************** + * Write Domain Logic + **************************************************************************/ + reg [C_WR_PNTR_WIDTH-1:0] diff_pntr = 0; + always @(posedge WR_CLK or posedge wr_rst_i) begin : gen_fifo_w + + /****** Reset fifo (case 1)***************************************/ + if (wr_rst_i == 1'b1) begin + num_wr_bits <= #`TCQ 0; + next_num_wr_bits = #`TCQ 0; + wr_ptr <= #`TCQ C_WR_DEPTH - 1; + rd_ptr_wrclk <= #`TCQ C_RD_DEPTH - 1; + ideal_wr_ack <= #`TCQ 0; + ideal_wr_count <= #`TCQ 0; + tmp_wr_listsize = #`TCQ 0; + rd_ptr_wrclk_next <= #`TCQ 0; + wr_pntr <= #`TCQ 0; + wr_pntr_rd1 <= #`TCQ 0; + rd_pntr_wr2 <= #`TCQ 0; + rd_pntr_wr3 <= #`TCQ 0; + rd_pntr_wr4 <= #`TCQ 0; + rd_pntr_wr <= #`TCQ 0; + + + end else begin //wr_rst_i==0 + + wr_pntr_rd1 <= #`TCQ wr_pntr; + + // Synchronize the rd_pntr in read domain + rd_pntr_wr2 <= #`TCQ rd_pntr_wr1; + rd_pntr_wr3 <= #`TCQ rd_pntr_wr2; + rd_pntr_wr4 <= #`TCQ rd_pntr_wr2; + rd_pntr_wr <= #`TCQ rd_pntr_wr4; + + + + //Determine the current number of words in the FIFO + tmp_wr_listsize = (C_DEPTH_RATIO_RD > 1) ? num_wr_bits/C_DOUT_WIDTH : + num_wr_bits/C_DIN_WIDTH; + rd_ptr_wrclk_next = rd_ptr; + if (rd_ptr_wrclk < rd_ptr_wrclk_next) begin + next_num_wr_bits = num_wr_bits - + C_DOUT_WIDTH*(rd_ptr_wrclk + C_RD_DEPTH + - rd_ptr_wrclk_next); + end else begin + next_num_wr_bits = num_wr_bits - + C_DOUT_WIDTH*(rd_ptr_wrclk - rd_ptr_wrclk_next); + end + + //If this is a write, handle the write by adding the value + // to the linked list, and updating all outputs appropriately + if (WR_EN == 1'b1) begin + if (FULL == 1'b1) begin + + //If the FIFO is full, do NOT perform the write, + // update flags accordingly + if ((tmp_wr_listsize + C_DEPTH_RATIO_RD - 1)/C_DEPTH_RATIO_RD + >= C_FIFO_WR_DEPTH) begin + //write unsuccessful - do not change contents + + //Do not acknowledge the write + ideal_wr_ack <= #`TCQ 0; + //Reminder that FIFO is still full + + ideal_wr_count <= #`TCQ num_write_words_sized_i; + + //If the FIFO is one from full, but reporting full + end else + if ((tmp_wr_listsize + C_DEPTH_RATIO_RD - 1)/C_DEPTH_RATIO_RD == + C_FIFO_WR_DEPTH-1) begin + //No change to FIFO + + //Write not successful + ideal_wr_ack <= #`TCQ 0; + //With DEPTH-1 words in the FIFO, it is almost_full + + ideal_wr_count <= #`TCQ num_write_words_sized_i; + + + //If the FIFO is completely empty, but it is + // reporting FULL for some reason (like reset) + end else + if ((tmp_wr_listsize + C_DEPTH_RATIO_RD - 1)/C_DEPTH_RATIO_RD <= + C_FIFO_WR_DEPTH-2) begin + //No change to FIFO + + //Write not successful + ideal_wr_ack <= #`TCQ 0; + //FIFO is really not close to full, so change flag status. + + ideal_wr_count <= #`TCQ num_write_words_sized_i; + end //(tmp_wr_listsize == 0) + + end else begin + + //If the FIFO is full, do NOT perform the write, + // update flags accordingly + if ((tmp_wr_listsize + C_DEPTH_RATIO_RD - 1)/C_DEPTH_RATIO_RD >= + C_FIFO_WR_DEPTH) begin + //write unsuccessful - do not change contents + + //Do not acknowledge the write + ideal_wr_ack <= #`TCQ 0; + //Reminder that FIFO is still full + + ideal_wr_count <= #`TCQ num_write_words_sized_i; + + //If the FIFO is one from full + end else + if ((tmp_wr_listsize + C_DEPTH_RATIO_RD - 1)/C_DEPTH_RATIO_RD == + C_FIFO_WR_DEPTH-1) begin + //Add value on DIN port to FIFO + write_fifo; + next_num_wr_bits = next_num_wr_bits + C_DIN_WIDTH; + + //Write successful, so issue acknowledge + // and no error + ideal_wr_ack <= #`TCQ 1; + //This write is CAUSING the FIFO to go full + + ideal_wr_count <= #`TCQ num_write_words_sized_i; + + //If the FIFO is 2 from full + end else + if ((tmp_wr_listsize + C_DEPTH_RATIO_RD - 1)/C_DEPTH_RATIO_RD == + C_FIFO_WR_DEPTH-2) begin + //Add value on DIN port to FIFO + write_fifo; + next_num_wr_bits = next_num_wr_bits + C_DIN_WIDTH; + //Write successful, so issue acknowledge + // and no error + ideal_wr_ack <= #`TCQ 1; + //Still 2 from full + + ideal_wr_count <= #`TCQ num_write_words_sized_i; + + //If the FIFO is not close to being full + end else + if ((tmp_wr_listsize + C_DEPTH_RATIO_RD - 1)/C_DEPTH_RATIO_RD < + C_FIFO_WR_DEPTH-2) begin + //Add value on DIN port to FIFO + write_fifo; + next_num_wr_bits = next_num_wr_bits + C_DIN_WIDTH; + //Write successful, so issue acknowledge + // and no error + ideal_wr_ack <= #`TCQ 1; + //Not even close to full. + + ideal_wr_count <= num_write_words_sized_i; + + end + + end + + end else begin //(WR_EN == 1'b1) + + //If user did not attempt a write, then do not + // give ack or err + ideal_wr_ack <= #`TCQ 0; + ideal_wr_count <= #`TCQ num_write_words_sized_i; + end + num_wr_bits <= #`TCQ next_num_wr_bits; + rd_ptr_wrclk <= #`TCQ rd_ptr; + + end //wr_rst_i==0 + end // write always + + + /*************************************************************************** + * Programmable FULL flags + ***************************************************************************/ + + always @(posedge WR_CLK or posedge RST_FULL_FF) begin : gen_pf + + if (RST_FULL_FF == 1'b1) begin + diff_pntr <= 0; + ideal_prog_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + end else begin + if (ram_wr_en) + diff_pntr <= #`TCQ (wr_pntr - adj_rd_pntr_wr + 2'h1); + else if (!ram_wr_en) + diff_pntr <= #`TCQ (wr_pntr - adj_rd_pntr_wr); + + if (RST_FULL_GEN) + ideal_prog_full <= #`TCQ 0; + //Single Programmable Full Constant Threshold + else if (C_PROG_FULL_TYPE == 1) begin + if (FULL == 0) begin + if (diff_pntr >= C_PROG_FULL_THRESH_ASSERT_VAL) + ideal_prog_full <= #`TCQ 1; + else + ideal_prog_full <= #`TCQ 0; + end else + ideal_prog_full <= #`TCQ ideal_prog_full; + //Two Programmable Full Constant Thresholds + end else if (C_PROG_FULL_TYPE == 2) begin + if (FULL == 0) begin + if (diff_pntr >= C_PROG_FULL_THRESH_ASSERT_VAL) + ideal_prog_full <= #`TCQ 1; + else if (diff_pntr < C_PROG_FULL_THRESH_NEGATE_VAL) + ideal_prog_full <= #`TCQ 0; + else + ideal_prog_full <= #`TCQ ideal_prog_full; + end else + ideal_prog_full <= #`TCQ ideal_prog_full; + //Single Programmable Full Threshold Input + end else if (C_PROG_FULL_TYPE == 3) begin + if (FULL == 0) begin + if (diff_pntr >= PROG_FULL_THRESH) + ideal_prog_full <= #`TCQ 1; + else + ideal_prog_full <= #`TCQ 0; + end else + ideal_prog_full <= #`TCQ ideal_prog_full; + //Two Programmable Full Threshold Inputs + end else if (C_PROG_FULL_TYPE == 4) begin + if (FULL == 0) begin + if (diff_pntr >= PROG_FULL_THRESH_ASSERT) + ideal_prog_full <= #`TCQ 1; + else if (diff_pntr < PROG_FULL_THRESH_NEGATE) + ideal_prog_full <= #`TCQ 0; + else + ideal_prog_full <= #`TCQ ideal_prog_full; + end else + ideal_prog_full <= #`TCQ ideal_prog_full; + end // C_PROG_FULL_TYPE + + end //wr_rst_i==0 + end // + + + /************************************************************************** + * Read Domain Logic + **************************************************************************/ + + + /********************************************************* + * Programmable EMPTY flags + *********************************************************/ + //Determine the Assert and Negate thresholds for Programmable Empty + + reg [C_RD_PNTR_WIDTH-1:0] pe_thr_assert_val = 0; + reg [C_RD_PNTR_WIDTH-1:0] pe_thr_negate_val = 0; + reg [C_RD_PNTR_WIDTH-1:0] diff_pntr_rd = 0; + always @* begin + + if (C_PROG_EMPTY_TYPE == 3) begin + + // If empty input threshold is selected, then subtract 2 for FWFT to + // compensate the FWFT stage, otherwise assign the input value. + if (C_PRELOAD_REGS == 1 && C_PRELOAD_LATENCY == 0) // FWFT + pe_thr_assert_val <= PROG_EMPTY_THRESH - 2'h2; + else + pe_thr_assert_val <= PROG_EMPTY_THRESH; + + end else if (C_PROG_EMPTY_TYPE == 4) begin + + // If empty input threshold is selected, then subtract 2 for FWFT to + // compensate the FWFT stage, otherwise assign the input value. + if (C_PRELOAD_REGS == 1 && C_PRELOAD_LATENCY == 0) begin // FWFT + pe_thr_assert_val <= PROG_EMPTY_THRESH_ASSERT - 2'h2; + pe_thr_negate_val <= PROG_EMPTY_THRESH_NEGATE - 2'h2; + end else begin + pe_thr_assert_val <= PROG_EMPTY_THRESH_ASSERT; + pe_thr_negate_val <= PROG_EMPTY_THRESH_NEGATE; + end + end else begin + + if (C_PRELOAD_REGS == 1 && C_PRELOAD_LATENCY == 0) begin // FWFT + pe_thr_assert_val <= C_PROG_EMPTY_THRESH_ASSERT_VAL - 2; + pe_thr_negate_val <= C_PROG_EMPTY_THRESH_NEGATE_VAL - 2; + end else begin + pe_thr_assert_val <= C_PROG_EMPTY_THRESH_ASSERT_VAL; + pe_thr_negate_val <= C_PROG_EMPTY_THRESH_NEGATE_VAL; + end + end + end // always @* + + always @(posedge RD_CLK or posedge rd_rst_i) begin : gen_pe + + if (rd_rst_i) begin + diff_pntr_rd <= #`TCQ 0; + ideal_prog_empty <= #`TCQ 1'b1; + end else begin + if (ram_rd_en) + diff_pntr_rd <= #`TCQ (adj_wr_pntr_rd - rd_pntr) - 1'h1; + else if (!ram_rd_en) + diff_pntr_rd <= #`TCQ (adj_wr_pntr_rd - rd_pntr); + else + diff_pntr_rd <= #`TCQ diff_pntr_rd; + + if (C_PROG_EMPTY_TYPE == 1) begin + if (EMPTY == 0) begin + if (diff_pntr_rd <= pe_thr_assert_val) + ideal_prog_empty <= #`TCQ 1; + else + ideal_prog_empty <= #`TCQ 0; + end else + ideal_prog_empty <= #`TCQ ideal_prog_empty; + end else if (C_PROG_EMPTY_TYPE == 2) begin + if (EMPTY == 0) begin + if (diff_pntr_rd <= pe_thr_assert_val) + ideal_prog_empty <= #`TCQ 1; + else if (diff_pntr_rd > pe_thr_negate_val) + ideal_prog_empty <= #`TCQ 0; + else + ideal_prog_empty <= #`TCQ ideal_prog_empty; + end else + ideal_prog_empty <= #`TCQ ideal_prog_empty; + end else if (C_PROG_EMPTY_TYPE == 3) begin + if (EMPTY == 0) begin + if (diff_pntr_rd <= pe_thr_assert_val) + ideal_prog_empty <= #`TCQ 1; + else + ideal_prog_empty <= #`TCQ 0; + end else + ideal_prog_empty <= #`TCQ ideal_prog_empty; + end else if (C_PROG_EMPTY_TYPE == 4) begin + if (EMPTY == 0) begin + if (diff_pntr_rd >= pe_thr_assert_val) + ideal_prog_empty <= #`TCQ 1; + else if (diff_pntr_rd > pe_thr_negate_val) + ideal_prog_empty <= #`TCQ 0; + else + ideal_prog_empty <= #`TCQ ideal_prog_empty; + end else + ideal_prog_empty <= #`TCQ ideal_prog_empty; + end //C_PROG_EMPTY_TYPE + end + end + + // block memory has a synchronous reset + always @(posedge RD_CLK) begin : gen_fifo_blkmemdout + // make it consistent with the core. + if (rd_rst_i) begin + // Reset err_type only if ECC is not selected + if (C_USE_ECC == 0 && C_MEMORY_TYPE < 2) + err_type <= #`TCQ 0; + + // BRAM resets synchronously + if (C_USE_DOUT_RST == 1 && C_MEMORY_TYPE < 2) begin + ideal_dout <= #`TCQ dout_reset_val; + ideal_dout_d1 <= #`TCQ dout_reset_val; + end + end + end //always + + always @(posedge RD_CLK or posedge rd_rst_i) begin : gen_fifo_r + + /****** Reset fifo (case 1)***************************************/ + if (rd_rst_i) begin + num_rd_bits <= #`TCQ 0; + next_num_rd_bits = #`TCQ 0; + rd_ptr <= #`TCQ C_RD_DEPTH -1; + rd_pntr <= #`TCQ 0; + rd_pntr_wr1 <= #`TCQ 0; + wr_pntr_rd2 <= #`TCQ 0; + wr_pntr_rd3 <= #`TCQ 0; + wr_pntr_rd <= #`TCQ 0; + wr_ptr_rdclk <= #`TCQ C_WR_DEPTH -1; + + // DRAM resets asynchronously + if (C_MEMORY_TYPE == 2 && C_USE_DOUT_RST == 1) + ideal_dout <= #`TCQ dout_reset_val; + + // Reset err_type only if ECC is not selected + if (C_USE_ECC == 0) + err_type <= #`TCQ 0; + ideal_valid <= #`TCQ 1'b0; + ideal_rd_count <= #`TCQ 0; + + end else begin //rd_rst_i==0 + + rd_pntr_wr1 <= #`TCQ rd_pntr; + + // Synchronize the wr_pntr in read domain + wr_pntr_rd2 <= #`TCQ wr_pntr_rd1; + wr_pntr_rd3 <= #`TCQ wr_pntr_rd2; + wr_pntr_rd <= #`TCQ wr_pntr_rd3; + + + + //Determine the current number of words in the FIFO + tmp_rd_listsize = (C_DEPTH_RATIO_WR > 1) ? num_rd_bits/C_DIN_WIDTH : + num_rd_bits/C_DOUT_WIDTH; + wr_ptr_rdclk_next = wr_ptr; + + if (wr_ptr_rdclk < wr_ptr_rdclk_next) begin + next_num_rd_bits = num_rd_bits + + C_DIN_WIDTH*(wr_ptr_rdclk +C_WR_DEPTH + - wr_ptr_rdclk_next); + end else begin + next_num_rd_bits = num_rd_bits + + C_DIN_WIDTH*(wr_ptr_rdclk - wr_ptr_rdclk_next); + end + + /*****************************************************************/ + // Read Operation - Read Latency 1 + /*****************************************************************/ + if (C_PRELOAD_LATENCY==1 || C_PRELOAD_LATENCY==2) begin + ideal_valid <= #`TCQ 1'b0; + + if (ram_rd_en == 1'b1) begin + + if (EMPTY == 1'b1) begin + + //If the FIFO is completely empty, and is reporting empty + if (tmp_rd_listsize/C_DEPTH_RATIO_WR <= 0) + begin + //Do not change the contents of the FIFO + + //Do not acknowledge the read from empty FIFO + ideal_valid <= #`TCQ 1'b0; + //Reminder that FIFO is still empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + end // if (tmp_rd_listsize <= 0) + + //If the FIFO is one from empty, but it is reporting empty + else if (tmp_rd_listsize/C_DEPTH_RATIO_WR == 1) + begin + //Do not change the contents of the FIFO + + //Do not acknowledge the read from empty FIFO + ideal_valid <= #`TCQ 1'b0; + //Note that FIFO is no longer empty, but is almost empty (has one word left) + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // if (tmp_rd_listsize == 1) + + //If the FIFO is two from empty, and is reporting empty + else if (tmp_rd_listsize/C_DEPTH_RATIO_WR == 2) + begin + //Do not change the contents of the FIFO + + //Do not acknowledge the read from empty FIFO + ideal_valid <= #`TCQ 1'b0; + //Fifo has two words, so is neither empty or almost empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // if (tmp_rd_listsize == 2) + + //If the FIFO is not close to empty, but is reporting that it is + // Treat the FIFO as empty this time, but unset EMPTY flags. + if ((tmp_rd_listsize/C_DEPTH_RATIO_WR > 2) && (tmp_rd_listsize/C_DEPTH_RATIO_WR 2) && (tmp_rd_listsize<=C_FIFO_RD_DEPTH-1)) + end // else: if(ideal_empty == 1'b1) + + else //if (ideal_empty == 1'b0) + begin + + //If the FIFO is completely full, and we are successfully reading from it + if (tmp_rd_listsize/C_DEPTH_RATIO_WR >= C_FIFO_RD_DEPTH) + begin + //Read the value from the FIFO + read_fifo; + next_num_rd_bits = next_num_rd_bits - C_DOUT_WIDTH; + + //Acknowledge the read from the FIFO, no error + ideal_valid <= #`TCQ 1'b1; + //Not close to empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // if (tmp_rd_listsize == C_FIFO_RD_DEPTH) + + //If the FIFO is not close to being empty + else if ((tmp_rd_listsize/C_DEPTH_RATIO_WR > 2) && (tmp_rd_listsize/C_DEPTH_RATIO_WR<=C_FIFO_RD_DEPTH)) + begin + //Read the value from the FIFO + read_fifo; + next_num_rd_bits = next_num_rd_bits - C_DOUT_WIDTH; + + //Acknowledge the read from the FIFO, no error + ideal_valid <= #`TCQ 1'b1; + //Not close to empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // if ((tmp_rd_listsize > 2) && (tmp_rd_listsize<=C_FIFO_RD_DEPTH-1)) + + //If the FIFO is two from empty + else if (tmp_rd_listsize/C_DEPTH_RATIO_WR == 2) + begin + //Read the value from the FIFO + read_fifo; + next_num_rd_bits = next_num_rd_bits - C_DOUT_WIDTH; + + //Acknowledge the read from the FIFO, no error + ideal_valid <= #`TCQ 1'b1; + //Fifo is not yet empty. It is going almost_empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // if (tmp_rd_listsize == 2) + + //If the FIFO is one from empty + else if ((tmp_rd_listsize/C_DEPTH_RATIO_WR == 1)) + begin + //Read the value from the FIFO + read_fifo; + next_num_rd_bits = next_num_rd_bits - C_DOUT_WIDTH; + + //Acknowledge the read from the FIFO, no error + ideal_valid <= #`TCQ 1'b1; + //Note that FIFO is GOING empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // if (tmp_rd_listsize == 1) + + + //If the FIFO is completely empty + else if (tmp_rd_listsize/C_DEPTH_RATIO_WR <= 0) + begin + //Do not change the contents of the FIFO + + //Do not acknowledge the read from empty FIFO + ideal_valid <= #`TCQ 1'b0; + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // if (tmp_rd_listsize <= 0) + + end // if (ideal_empty == 1'b0) + + end //(RD_EN == 1'b1) + + else //if (RD_EN == 1'b0) + begin + //If user did not attempt a read, do not give an ack or err + ideal_valid <= #`TCQ 1'b0; + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // else: !if(RD_EN == 1'b1) + + /*****************************************************************/ + // Read Operation - Read Latency 0 + /*****************************************************************/ + end else if (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) begin + ideal_valid <= #`TCQ 1'b0; + if (ram_rd_en == 1'b1) begin + + if (EMPTY == 1'b1) begin + + //If the FIFO is completely empty, and is reporting empty + if (tmp_rd_listsize/C_DEPTH_RATIO_WR <= 0) begin + //Do not change the contents of the FIFO + + //Do not acknowledge the read from empty FIFO + ideal_valid <= #`TCQ 1'b0; + //Reminder that FIFO is still empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + //If the FIFO is one from empty, but it is reporting empty + end else if (tmp_rd_listsize/C_DEPTH_RATIO_WR == 1) begin + //Do not change the contents of the FIFO + + //Do not acknowledge the read from empty FIFO + ideal_valid <= #`TCQ 1'b0; + //Note that FIFO is no longer empty, but is almost empty (has one word left) + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + //If the FIFO is two from empty, and is reporting empty + end else if (tmp_rd_listsize/C_DEPTH_RATIO_WR == 2) begin + //Do not change the contents of the FIFO + + //Do not acknowledge the read from empty FIFO + ideal_valid <= #`TCQ 1'b0; + //Fifo has two words, so is neither empty or almost empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + //If the FIFO is not close to empty, but is reporting that it is + // Treat the FIFO as empty this time, but unset EMPTY flags. + end else if ((tmp_rd_listsize/C_DEPTH_RATIO_WR > 2) && + (tmp_rd_listsize/C_DEPTH_RATIO_WR 2) && (tmp_rd_listsize<=C_FIFO_RD_DEPTH-1)) + + end else begin + + //If the FIFO is completely full, and we are successfully reading from it + if (tmp_rd_listsize/C_DEPTH_RATIO_WR >= C_FIFO_RD_DEPTH) begin + //Read the value from the FIFO + read_fifo; + next_num_rd_bits = next_num_rd_bits - C_DOUT_WIDTH; + + //Acknowledge the read from the FIFO, no error + ideal_valid <= #`TCQ 1'b1; + //Not close to empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + //If the FIFO is not close to being empty + end else if ((tmp_rd_listsize/C_DEPTH_RATIO_WR > 2) && + (tmp_rd_listsize/C_DEPTH_RATIO_WR<=C_FIFO_RD_DEPTH)) begin + //Read the value from the FIFO + read_fifo; + next_num_rd_bits = next_num_rd_bits - C_DOUT_WIDTH; + + //Acknowledge the read from the FIFO, no error + ideal_valid <= #`TCQ 1'b1; + //Not close to empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + //If the FIFO is two from empty + end else if (tmp_rd_listsize/C_DEPTH_RATIO_WR == 2) begin + //Read the value from the FIFO + read_fifo; + next_num_rd_bits = next_num_rd_bits - C_DOUT_WIDTH; + + //Acknowledge the read from the FIFO, no error + ideal_valid <= #`TCQ 1'b1; + //Fifo is not yet empty. It is going almost_empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + //If the FIFO is one from empty + end else if (tmp_rd_listsize/C_DEPTH_RATIO_WR == 1) begin + //Read the value from the FIFO + read_fifo; + next_num_rd_bits = next_num_rd_bits - C_DOUT_WIDTH; + + //Acknowledge the read from the FIFO, no error + ideal_valid <= #`TCQ 1'b1; + //Note that FIFO is GOING empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + //If the FIFO is completely empty + end else if (tmp_rd_listsize/C_DEPTH_RATIO_WR <= 0) begin + //Do not change the contents of the FIFO + + //Do not acknowledge the read from empty FIFO + ideal_valid <= #`TCQ 1'b0; + //Reminder that FIFO is still empty + + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // if (tmp_rd_listsize <= 0) + + end // if (ideal_empty == 1'b0) + + end else begin//(RD_EN == 1'b0) + + + //If user did not attempt a read, do not give an ack or err + ideal_valid <= #`TCQ 1'b0; + ideal_rd_count <= #`TCQ num_read_words_sized_i; + + end // else: !if(RD_EN == 1'b1) + end //if (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) + + num_rd_bits <= #`TCQ next_num_rd_bits; + wr_ptr_rdclk <= #`TCQ wr_ptr; + end //rd_rst_i==0 + end //always + +endmodule // fifo_generator_v6_1_bhv_ver_as + + +/******************************************************************************* + * Declaration of top-level module + ******************************************************************************/ +module fifo_generator_v6_1_bhv_ver_ss + + /************************************************************************** + * Declare user parameters and their defaults + *************************************************************************/ + #( + parameter C_DATA_COUNT_WIDTH = 2, + parameter C_DIN_WIDTH = 8, + parameter C_DOUT_RST_VAL = "", + parameter C_DOUT_WIDTH = 8, + parameter C_FULL_FLAGS_RST_VAL = 1, + parameter C_HAS_ALMOST_EMPTY = 0, + parameter C_HAS_ALMOST_FULL = 0, + parameter C_HAS_DATA_COUNT = 0, + parameter C_HAS_OVERFLOW = 0, + parameter C_HAS_RD_DATA_COUNT = 0, + parameter C_HAS_RST = 0, + parameter C_HAS_SRST = 0, + parameter C_HAS_UNDERFLOW = 0, + parameter C_HAS_VALID = 0, + parameter C_HAS_WR_ACK = 0, + parameter C_HAS_WR_DATA_COUNT = 0, + parameter C_IMPLEMENTATION_TYPE = 0, + parameter C_MEMORY_TYPE = 1, + parameter C_OVERFLOW_LOW = 0, + parameter C_PRELOAD_LATENCY = 1, + parameter C_PRELOAD_REGS = 0, + parameter C_PROG_EMPTY_THRESH_ASSERT_VAL = 0, + parameter C_PROG_EMPTY_THRESH_NEGATE_VAL = 0, + parameter C_PROG_EMPTY_TYPE = 0, + parameter C_PROG_FULL_THRESH_ASSERT_VAL = 0, + parameter C_PROG_FULL_THRESH_NEGATE_VAL = 0, + parameter C_PROG_FULL_TYPE = 0, + parameter C_RD_DATA_COUNT_WIDTH = 2, + parameter C_RD_DEPTH = 256, + parameter C_RD_PNTR_WIDTH = 8, + parameter C_UNDERFLOW_LOW = 0, + parameter C_USE_DOUT_RST = 0, + parameter C_USE_EMBEDDED_REG = 0, + parameter C_USE_FWFT_DATA_COUNT = 0, + parameter C_VALID_LOW = 0, + parameter C_WR_ACK_LOW = 0, + parameter C_WR_DATA_COUNT_WIDTH = 2, + parameter C_WR_DEPTH = 256, + parameter C_WR_PNTR_WIDTH = 8, + parameter C_USE_ECC = 0, + parameter C_ENABLE_RST_SYNC = 1, + parameter C_ERROR_INJECTION_TYPE = 0 + ) + + /************************************************************************** + * Declare Input and Output Ports + *************************************************************************/ + ( + //Inputs + input CLK, + input [C_DIN_WIDTH-1:0] DIN, + input [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH, + input [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_ASSERT, + input [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_NEGATE, + input [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH, + input [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_ASSERT, + input [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_NEGATE, + input RD_EN, + input RST, + input RST_FULL_GEN, + input RST_FULL_FF, + input SRST, + input WR_EN, + input INJECTDBITERR, + input INJECTSBITERR, + + //Outputs + output ALMOST_EMPTY, + output ALMOST_FULL, + output reg [C_DATA_COUNT_WIDTH-1:0] DATA_COUNT, + output [C_DOUT_WIDTH-1:0] DOUT, + output EMPTY, + output FULL, + output OVERFLOW, + output PROG_EMPTY, + output PROG_FULL, + output VALID, + output UNDERFLOW, + output WR_ACK, + output SBITERR, + output DBITERR + ); + + + /*************************************************************************** + * Parameters used as constants + **************************************************************************/ + //When RST is present, set FULL reset value to '1'. + //If core has no RST, make sure FULL powers-on as '0'. + //The reset value assignments for FULL, ALMOST_FULL, and PROG_FULL are not + //changed for v3.2(IP2_Im). When the core has Sync Reset, C_HAS_SRST=1 and C_HAS_RST=0. + // Therefore, during SRST, all the FULL flags reset to 0. + parameter C_HAS_FAST_FIFO = 0; + parameter C_FIFO_WR_DEPTH = C_WR_DEPTH; + parameter C_FIFO_RD_DEPTH = C_RD_DEPTH; + + /************************************************************************** + * FIFO Contents Tracking and Data Count Calculations + *************************************************************************/ + // Memory which will be used to simulate a FIFO + reg [C_DIN_WIDTH-1:0] memory[C_WR_DEPTH-1:0]; + // Local parameters used to determine whether to inject ECC error or not + localparam SYMMETRIC_PORT = (C_DIN_WIDTH == C_DOUT_WIDTH) ? 1 : 0; + localparam ERR_INJECTION = (C_ERROR_INJECTION_TYPE != 0) ? 1 : 0; + localparam ENABLE_ERR_INJECTION = C_USE_ECC && SYMMETRIC_PORT && ERR_INJECTION; + // Array that holds the error injection type (single/double bit error) on + // a specific write operation, which is returned on read to corrupt the + // output data. + reg [1:0] ecc_err[C_WR_DEPTH-1:0]; + + //The amount of data stored in the FIFO at any time is given + // by num_bits. + //num_bits is calculated by from the total words in the FIFO. + reg [31:0] num_bits; + + //The write pointer - tracks write operations + // (Works opposite to core: wr_ptr is a DOWN counter) + reg [31:0] wr_ptr; + + //The write pointer - tracks read operations + // (Works opposite to core: rd_ptr is a DOWN counter) + reg [31:0] rd_ptr; + + /************************** + * Data Count + *************************/ + //Amount of data stored in the FIFO scaled to read words + wire [31:0] num_read_words = num_bits/C_DOUT_WIDTH; + //num_read_words delayed 1 clock cycle + reg [31:0] num_read_words_q; + + //Amount of data stored in the FIFO scaled to write words + wire [31:0] num_write_words = num_bits/C_DIN_WIDTH; + //num_write_words delayed 1 clock cycle + reg [31:0] num_write_words_q; + + + /************************************************************************** + * Internal Registers and wires + *************************************************************************/ + + //Temporary signals used for calculating the model's outputs. These + //are only used in the assign statements immediately following wire, + //parameter, and function declarations. + wire underflow_i; + wire valid_i; + wire valid_out; + + //Ideal FIFO signals. These are the raw output of the behavioral model, + //which behaves like an ideal FIFO. + reg [1:0] err_type = 0; + reg [1:0] err_type_d1 = 0; + reg [C_DOUT_WIDTH-1:0] ideal_dout = 0; + reg [C_DOUT_WIDTH-1:0] ideal_dout_d1 = 0; + wire [C_DOUT_WIDTH-1:0] ideal_dout_out; + wire fwft_enabled; + reg ideal_wr_ack = 0; + reg ideal_valid = 0; + reg ideal_overflow = 0; + reg ideal_underflow = 0; + reg ideal_full = 0; + reg ideal_empty = 1; + reg ideal_almost_full = 0; + reg ideal_almost_empty = 1; + reg ideal_prog_full = 0; + reg ideal_prog_empty = 1; + + //Assorted reg values for delayed versions of signals + reg valid_d1 = 0; + reg prog_full_d = 0; + reg prog_empty_d = 1; + + wire rst_i; + wire srst_i; + + //Delayed version of RST + reg rst_q; + reg rst_qq; + + //user specified value for reseting the size of the fifo + reg [C_DOUT_WIDTH-1:0] dout_reset_val = 0; + + + /**************************************************************************** + * Function Declarations + ***************************************************************************/ + + /************************************************************************** + * write_fifo + * This task writes a word to the FIFO memory and updates the + * write pointer. + * FIFO size is relative to write domain. + ***************************************************************************/ + task write_fifo; + reg [1:0] corrupted_data; + begin + memory[wr_ptr] <= DIN; + // Store the type of error injection (double/single) on write + case (C_ERROR_INJECTION_TYPE) + 3: ecc_err[wr_ptr] <= {INJECTDBITERR,INJECTSBITERR}; + 2: ecc_err[wr_ptr] <= {INJECTDBITERR,1'b0}; + 1: ecc_err[wr_ptr] <= {1'b0,INJECTSBITERR}; + default: ecc_err[wr_ptr] <= 0; + endcase + if (wr_ptr == 0) begin + wr_ptr <= C_WR_DEPTH - 1; + end else begin + wr_ptr <= wr_ptr - 1; + end + end + endtask // write_fifo + + /************************************************************************** + * read_fifo + * This task reads a word from the FIFO memory and updates the read + * pointer. It's output is the ideal_dout bus. + * FIFO size is relative to write domain. + ***************************************************************************/ + task read_fifo; + reg [C_DOUT_WIDTH-1:0] tmp_dout; + reg [1:0] tmp_ecc_err; + begin + tmp_dout = memory[rd_ptr][C_DOUT_WIDTH-1:0]; + // Retreive the error injection type. Based on the error injection type + // corrupt the output data. + tmp_ecc_err = ecc_err[rd_ptr]; + if (ENABLE_ERR_INJECTION) begin + if (tmp_ecc_err[1]) begin // Corrupt the output data only for double bit error + if (C_DOUT_WIDTH == 1) + tmp_dout = tmp_dout[C_DOUT_WIDTH-1:0]; + else if (C_DOUT_WIDTH == 2) + tmp_dout = {~tmp_dout[C_DOUT_WIDTH-1],~tmp_dout[C_DOUT_WIDTH-2]}; + else + tmp_dout = {~tmp_dout[C_DOUT_WIDTH-1],~tmp_dout[C_DOUT_WIDTH-2],(tmp_dout << 2)}; + end else begin + tmp_dout = tmp_dout[C_DOUT_WIDTH-1:0]; + end + err_type <= {tmp_ecc_err[1], tmp_ecc_err[0] & !tmp_ecc_err[1]}; + end else begin + err_type <= 0; + end + ideal_dout <= tmp_dout; + + if (rd_ptr == 0) begin + rd_ptr <= C_RD_DEPTH - 1; + end else begin + rd_ptr <= rd_ptr - 1; + end + end + endtask + + /**************************************************************************** + * log2_val + * Returns the 'log2' value for the input value for the supported ratios + ***************************************************************************/ + function [31:0] log2_val; + input [31:0] binary_val; + + begin + if (binary_val == 8) begin + log2_val = 3; + end else if (binary_val == 4) begin + log2_val = 2; + end else begin + log2_val = 1; + end + end + endfunction + + /**************************************************************************** + * hexstr_conv + * Converts a string of type hex to a binary value (for C_DOUT_RST_VAL) + ***************************************************************************/ + function [C_DOUT_WIDTH-1:0] hexstr_conv; + input [(C_DOUT_WIDTH*8)-1:0] def_data; + + integer index,i,j; + reg [3:0] bin; + + begin + index = 0; + hexstr_conv = 'b0; + for( i=C_DOUT_WIDTH-1; i>=0; i=i-1 ) + begin + case (def_data[7:0]) + 8'b00000000 : + begin + bin = 4'b0000; + i = -1; + end + 8'b00110000 : bin = 4'b0000; + 8'b00110001 : bin = 4'b0001; + 8'b00110010 : bin = 4'b0010; + 8'b00110011 : bin = 4'b0011; + 8'b00110100 : bin = 4'b0100; + 8'b00110101 : bin = 4'b0101; + 8'b00110110 : bin = 4'b0110; + 8'b00110111 : bin = 4'b0111; + 8'b00111000 : bin = 4'b1000; + 8'b00111001 : bin = 4'b1001; + 8'b01000001 : bin = 4'b1010; + 8'b01000010 : bin = 4'b1011; + 8'b01000011 : bin = 4'b1100; + 8'b01000100 : bin = 4'b1101; + 8'b01000101 : bin = 4'b1110; + 8'b01000110 : bin = 4'b1111; + 8'b01100001 : bin = 4'b1010; + 8'b01100010 : bin = 4'b1011; + 8'b01100011 : bin = 4'b1100; + 8'b01100100 : bin = 4'b1101; + 8'b01100101 : bin = 4'b1110; + 8'b01100110 : bin = 4'b1111; + default : + begin + bin = 4'bx; + end + endcase + for( j=0; j<4; j=j+1) + begin + if ((index*4)+j < C_DOUT_WIDTH) + begin + hexstr_conv[(index*4)+j] = bin[j]; + end + end + index = index + 1; + def_data = def_data >> 8; + end + end + endfunction + + + /************************************************************************* + * Initialize Signals for clean power-on simulation + *************************************************************************/ + initial begin + num_bits = 0; + num_read_words_q = 0; + num_write_words_q = 0; + rd_ptr = C_RD_DEPTH -1; + wr_ptr = C_WR_DEPTH -1; + dout_reset_val = hexstr_conv(C_DOUT_RST_VAL); + ideal_dout = dout_reset_val; + err_type = 0; + ideal_wr_ack = 1'b0; + ideal_valid = 1'b0; + valid_d1 = 1'b0; + ideal_overflow = 1'b0; + ideal_underflow = 1'b0; + ideal_full = 1'b0; + ideal_empty = 1'b1; + ideal_almost_full = 1'b0; + ideal_almost_empty = 1'b1; + ideal_prog_full = 1'b0; + ideal_prog_empty = 1'b1; + prog_full_d = 1'b0; + prog_empty_d = 1'b1; + rst_q = 1'b0; + rst_qq = 1'b0; + end + + + /************************************************************************* + * Connect the module inputs and outputs to the internal signals of the + * behavioral model. + *************************************************************************/ + //Inputs + /* + wire CLK; + wire [C_DIN_WIDTH-1:0] DIN; + wire [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH; + wire [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_ASSERT; + wire [C_RD_PNTR_WIDTH-1:0] PROG_EMPTY_THRESH_NEGATE; + wire [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH; + wire [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_ASSERT; + wire [C_WR_PNTR_WIDTH-1:0] PROG_FULL_THRESH_NEGATE; + wire RD_EN; + wire RST; + wire WR_EN; + */ + + //Outputs + generate + if (C_HAS_ALMOST_EMPTY==1) begin : blockAE10 + assign ALMOST_EMPTY = ideal_almost_empty; + end + endgenerate + + generate + if (C_HAS_ALMOST_FULL==1) begin : blockAF10 + assign ALMOST_FULL = ideal_almost_full; + end + endgenerate + + //Dout may change behavior based on latency + assign fwft_enabled = (C_PRELOAD_LATENCY == 0 && C_PRELOAD_REGS == 1)? + 1: 0; + assign ideal_dout_out= ((C_USE_EMBEDDED_REG==1 && (fwft_enabled == 0)) && + (C_MEMORY_TYPE==0 || C_MEMORY_TYPE==1))? + ideal_dout_d1: ideal_dout; + assign DOUT = ideal_dout_out; + + // Assign SBITERR and DBITERR based on latency + assign SBITERR = (C_ERROR_INJECTION_TYPE == 1 || C_ERROR_INJECTION_TYPE == 3) && + ((C_USE_EMBEDDED_REG==1 && (fwft_enabled == 0)) && + (C_MEMORY_TYPE==0 || C_MEMORY_TYPE==1)) ? + err_type_d1[0]: err_type[0]; + assign DBITERR = (C_ERROR_INJECTION_TYPE == 2 || C_ERROR_INJECTION_TYPE == 3) && + ((C_USE_EMBEDDED_REG==1 && (fwft_enabled == 0)) && + (C_MEMORY_TYPE==0 || C_MEMORY_TYPE==1)) ? + err_type_d1[1]: err_type[1]; + + assign EMPTY = ideal_empty; + assign FULL = ideal_full; + + //Overflow may be active-low + generate + if (C_HAS_OVERFLOW==1) begin : blockOF10 + assign OVERFLOW = ideal_overflow ? !C_OVERFLOW_LOW : C_OVERFLOW_LOW; + end + endgenerate + + assign PROG_EMPTY = ideal_prog_empty; + assign PROG_FULL = ideal_prog_full; + + //Valid may change behavior based on latency or active-low + generate + if (C_HAS_VALID==1) begin : blockVL10 + assign valid_i = (C_PRELOAD_LATENCY==0) ? (RD_EN & ~EMPTY) : ideal_valid; + assign valid_out = (C_PRELOAD_LATENCY==2 && + (C_MEMORY_TYPE==0 || C_MEMORY_TYPE==1))? + valid_d1: valid_i; + assign VALID = valid_out ? !C_VALID_LOW : C_VALID_LOW; + end + endgenerate + + //Trim data count differently depending on set widths + generate + if ((C_HAS_DATA_COUNT == 1) && + (C_DATA_COUNT_WIDTH > C_RD_PNTR_WIDTH)) begin : blockDC1 + always @(num_read_words) + DATA_COUNT = num_read_words[C_RD_PNTR_WIDTH:0]; + end else if (C_HAS_DATA_COUNT == 1) begin : blockDC2 + always @(num_read_words) + DATA_COUNT = num_read_words[C_RD_PNTR_WIDTH-1:C_RD_PNTR_WIDTH-C_DATA_COUNT_WIDTH]; + end //if + endgenerate + + //Underflow may change behavior based on latency or active-low + generate + if (C_HAS_UNDERFLOW==1) begin : blockUF10 + assign underflow_i = ideal_underflow; + assign UNDERFLOW = underflow_i ? !C_UNDERFLOW_LOW : C_UNDERFLOW_LOW; + end + endgenerate + + + //Write acknowledge may be active low + generate + if (C_HAS_WR_ACK==1) begin : blockWK10 + assign WR_ACK = ideal_wr_ack ? !C_WR_ACK_LOW : C_WR_ACK_LOW; + end + endgenerate + + + /***************************************************************************** + * Internal reset logic + ****************************************************************************/ + assign srst_i = C_HAS_SRST ? SRST : 0; + assign rst_i = C_HAS_RST ? RST : 0; + + /************************************************************************** + * Assorted registers for delayed versions of signals + **************************************************************************/ + //Capture delayed version of valid + generate + if (C_HAS_VALID==1) begin : blockVL20 + always @(posedge CLK or posedge rst_i) begin + if (rst_i == 1'b1) begin + valid_d1 <= #`TCQ 1'b0; + end else begin + if (srst_i) begin + valid_d1 <= #`TCQ 1'b0; + end else begin + valid_d1 <= #`TCQ valid_i; + end + end + end // always @ (posedge CLK or posedge rst_i) + end + endgenerate + + + // block memory has a synchronous reset + always @(posedge CLK) begin : gen_fifo_blkmemdout_emb + // make it consistent with the core. + if (rst_i || srst_i) begin + // BRAM resets synchronously + if (C_USE_DOUT_RST == 1 && C_MEMORY_TYPE < 2) begin + ideal_dout_d1 <= #`TCQ dout_reset_val; + end + end + end //always + + reg ram_rd_en_d1 = 1'b0; + //Capture delayed version of dout + always @(posedge CLK or posedge rst_i) begin + if (rst_i == 1'b1) begin + // Reset err_type only if ECC is not selected + if (C_USE_ECC == 0) + err_type_d1 <= #`TCQ 0; + + // DRAM and SRAM reset asynchronously + if ((C_MEMORY_TYPE == 2 || C_MEMORY_TYPE == 3) && C_USE_DOUT_RST == 1) + ideal_dout_d1 <= #`TCQ dout_reset_val; + + ram_rd_en_d1 <= #`TCQ 1'b0; + end else begin + ram_rd_en_d1 <= #`TCQ RD_EN & !EMPTY; + if (srst_i) begin + ram_rd_en_d1 <= #`TCQ 1'b0; + // Reset err_type only if ECC is not selected + if (C_USE_ECC == 0) + err_type_d1 <= #`TCQ 0; + // Reset DRAM and SRAM based FIFO, BRAM based FIFO is reset above + if ((C_MEMORY_TYPE == 2 || C_MEMORY_TYPE == 3) && C_USE_DOUT_RST == 1) + ideal_dout_d1 <= #`TCQ dout_reset_val; + end else if (ram_rd_en_d1) begin + ideal_dout_d1 <= #`TCQ ideal_dout; + err_type_d1 <= #`TCQ err_type; + end + end + end + + /************************************************************************** + * Overflow and Underflow Flag calculation + * (handled separately because they don't support rst) + **************************************************************************/ + generate + if (C_HAS_OVERFLOW==1) begin : blockOF20 + always @(posedge CLK) begin + ideal_overflow <= #`TCQ WR_EN & ideal_full; + end + end + endgenerate + + generate + if (C_HAS_UNDERFLOW==1) begin : blockUF20 + always @(posedge CLK) begin + ideal_underflow <= #`TCQ ideal_empty & RD_EN; + end + end + endgenerate + + /************************************************************************* + * Write and Read Logic + ************************************************************************/ + always @(posedge CLK or posedge rst_i) + begin : gen_wr_ack_resp + + //Register reset + rst_q <= #`TCQ rst_i; + rst_qq <= #`TCQ rst_q; + + end // block: gen_wr_ack_resp + + // block memory has a synchronous reset + always @(posedge CLK) begin : gen_fifo_blkmemdout + //Changed the latency of during async reset to '1' instead of '2' to + // make it consistent with the core. + if (rst_i || rst_q || srst_i) begin + // Reset err_type only if ECC is not selected + if (C_USE_ECC == 0 && C_MEMORY_TYPE == 1) + err_type <= #`TCQ 0; + /******Initialize Read Domain Signals*********************************/ + if (C_USE_DOUT_RST == 1 && C_MEMORY_TYPE < 2) begin + ideal_dout <= #`TCQ dout_reset_val; + end + end + end //always + + // FULL_FLAG_RESET value given for SRST as well. + reg srst_i_d1 = 0; + reg srst_i_d2 = 0; + always @(posedge CLK or posedge RST_FULL_FF) begin : gen_fifo + + /****** Reset fifo - Asynchronous Reset**********************************/ + //Changed the latency of during async reset to '1' instead of '2' to + // make it consistent with the core. + if (RST_FULL_FF) begin //v3.2 + /******Initialize Generic FIFO constructs*****************************/ + num_bits <= #`TCQ 0; + wr_ptr <= #`TCQ C_WR_DEPTH - 1; + rd_ptr <= #`TCQ C_RD_DEPTH - 1; + num_read_words_q <= #`TCQ 0; + num_write_words_q <= #`TCQ 0; + // Reset err_type only if ECC is not selected + if (C_USE_ECC == 0 && C_MEMORY_TYPE != 1) + err_type <= #`TCQ 0; + + + /******Initialize Write Domain Signals********************************/ + ideal_wr_ack <= #`TCQ 0; + ideal_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + ideal_almost_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + + /******Initialize Read Domain Signals*********************************/ + // DRAM and SRAM reset asynchronously + if (C_USE_DOUT_RST == 1 && (C_MEMORY_TYPE == 2 || C_MEMORY_TYPE == 3)) begin + ideal_dout <= #`TCQ dout_reset_val; + end + ideal_valid <= #`TCQ 1'b0; + ideal_empty <= #`TCQ 1'b1; + ideal_almost_empty <= #`TCQ 1'b1; + + end else begin + // Register SRST twice to be consistant with RST behavior + srst_i_d1 <= #`TCQ srst_i; + srst_i_d2 <= #`TCQ srst_i_d1; + if (srst_i) begin + // SRST is available only for Sync BRAM, DRAM and SRAM. + if (C_MEMORY_TYPE == 1 || C_MEMORY_TYPE == 2 || C_MEMORY_TYPE == 3) begin + /******Initialize Generic FIFO constructs***********************/ + num_bits <= #`TCQ 0; + wr_ptr <= #`TCQ C_WR_DEPTH - 1; + rd_ptr <= #`TCQ C_RD_DEPTH - 1; + num_read_words_q <= #`TCQ 0; + num_write_words_q <= #`TCQ 0; + // Reset err_type only if ECC is not selected + if (C_USE_ECC == 0) + err_type <= #`TCQ 0; + + /******Initialize Write Domain Signals**************************/ + ideal_wr_ack <= #`TCQ 0; + ideal_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + ideal_almost_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + + /******Initialize Read Domain Signals***************************/ + //Reset DOUT of Sync DRAM/Shift RAM. Sync BRAM DOUT was reset in the + // above always block. + if (C_USE_DOUT_RST == 1 && (C_MEMORY_TYPE == 2 || C_MEMORY_TYPE == 3)) begin + ideal_dout <= #`TCQ dout_reset_val; + end + ideal_valid <= #`TCQ 1'b0; + ideal_empty <= #`TCQ 1'b1; + ideal_almost_empty <= #`TCQ 1'b1; + end + + end else if ((srst_i_d1 || srst_i_d2) && (C_FULL_FLAGS_RST_VAL == 1)) begin //Hold full flag reset value set during RST/SRST + ideal_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + ideal_almost_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + end else begin //normal operating conditions + /********************************************************************/ + // Synchronous FIFO Condition #1 : Writing and not reading + /********************************************************************/ + ideal_valid <= #`TCQ 1'b0; + if (WR_EN & ~RD_EN) begin + + /*********************************/ + //If the FIFO is full, do NOT perform the write, + // update flags accordingly + /*********************************/ + if (num_write_words >= C_FIFO_WR_DEPTH) begin + ideal_wr_ack <= #`TCQ 0; + + //still full + ideal_full <= #`TCQ 1'b1; + ideal_almost_full <= #`TCQ 1'b1; + + //write unsuccessful - do not change contents + + // no read attempted + ideal_valid <= #`TCQ 1'b0; + + //Not near empty + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + + /*********************************/ + //If the FIFO is reporting FULL + // (Startup condition) + /*********************************/ + end else if ((num_write_words < C_FIFO_WR_DEPTH) && (ideal_full == 1'b1)) begin + ideal_wr_ack <= #`TCQ 0; + + //still full + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //write unsuccessful - do not change contents + + // no read attempted + ideal_valid <= #`TCQ 1'b0; + + //FIFO EMPTY in this state can not be determined + //ideal_empty <= 1'b0; + //ideal_almost_empty <= 1'b0; + + + /*********************************/ + //If the FIFO is one from full + /*********************************/ + end else if (num_write_words == C_FIFO_WR_DEPTH-1) begin + //good write + ideal_wr_ack <= #`TCQ 1; + + //FIFO is one from FULL and going FULL + ideal_full <= #`TCQ 1'b1; + ideal_almost_full <= #`TCQ 1'b1; + + //Add input data + write_fifo; + + // no read attempted + ideal_valid <= #`TCQ 1'b0; + + //Not near empty + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + num_bits <= num_bits + C_DIN_WIDTH; + + /*********************************/ + //If the FIFO is 2 from full + /*********************************/ + end else if (num_write_words == C_FIFO_WR_DEPTH-2) begin + //good write + ideal_wr_ack <= #`TCQ 1; + + //2 from full, and writing, so set almost_full + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b1; + + //Add input data + write_fifo; + + //no read attempted + ideal_valid <= #`TCQ 1'b0; + + //Not near empty + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + num_bits <= #`TCQ num_bits + C_DIN_WIDTH; + + /*********************************/ + //If the FIFO is ALMOST EMPTY + /*********************************/ + end else if (num_read_words == 1) begin + //good write + ideal_wr_ack <= #`TCQ 1; + + //Not near FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //Add input data + write_fifo; + + // no read attempted + ideal_valid <= #`TCQ 1'b0; + + //Leaving ALMOST_EMPTY + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + num_bits <= #`TCQ num_bits + C_DIN_WIDTH; + + /*********************************/ + //If the FIFO is EMPTY + /*********************************/ + end else if (num_read_words == 0) begin + // good write + ideal_wr_ack <= #`TCQ 1; + + //Not near FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //Add input data + write_fifo; + + // no read attempted + ideal_valid <= #`TCQ 1'b0; + + //Leaving EMPTY (still ALMOST_EMPTY) + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b1; + + num_bits <= #`TCQ num_bits + C_DIN_WIDTH; + + /*********************************/ + //If the FIFO is not near EMPTY or FULL + /*********************************/ + end else begin + // good write + ideal_wr_ack <= #`TCQ 1; + + //Not near FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //Add input data + write_fifo; + + // no read attempted + ideal_valid <= #`TCQ 1'b0; + + //Not near EMPTY + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + num_bits <= #`TCQ num_bits + C_DIN_WIDTH; + + end // average case + + + /******************************************************************/ + // Synchronous FIFO Condition #2 : Reading and not writing + /******************************************************************/ + end else if (~WR_EN & RD_EN) begin + + /*********************************/ + //If the FIFO is EMPTY + /*********************************/ + if ((num_read_words == 0) || (ideal_empty == 1'b1)) begin + //no write attemped + ideal_wr_ack <= #`TCQ 0; + + //FIFO is not near FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //Read will fail + ideal_valid <= #`TCQ 1'b0; + + //FIFO is still empty + ideal_empty <= #`TCQ 1'b1; + ideal_almost_empty <= #`TCQ 1'b1; + + //No read + + /*********************************/ + //If the FIFO is ALMOST EMPTY + /*********************************/ + end else if (num_read_words == 1) begin + //no write attempted + ideal_wr_ack <= #`TCQ 0; + + //FIFO is not near FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //Read successful + ideal_valid <= #`TCQ 1'b1; + + //This read will make FIFO go empty + ideal_empty <= #`TCQ 1'b1; + ideal_almost_empty <= #`TCQ 1'b1; + + //Get the data from the FIFO + read_fifo; + num_bits <= #`TCQ num_bits - C_DIN_WIDTH; + + + /*********************************/ + //If the FIFO is 2 from EMPTY + /*********************************/ + end else if (num_read_words == 2) begin + + //no write attempted + ideal_wr_ack <= #`TCQ 0; + + //FIFO is not near FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //Read successful + ideal_valid <= #`TCQ 1'b1; + + //FIFO is going ALMOST_EMPTY + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b1; + + //Get the data from the FIFO + read_fifo; + num_bits <= #`TCQ num_bits - C_DOUT_WIDTH; + + + + /*********************************/ + //If the FIFO is one from full + /*********************************/ + end else if (num_write_words == C_FIFO_WR_DEPTH-1) begin + + //no write attempted + ideal_wr_ack <= #`TCQ 0; + + //FIFO is leaving ALMOST FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //Read successful + ideal_valid <= #`TCQ 1'b1; + + //Not near empty + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + //Read from the FIFO + read_fifo; + num_bits <= #`TCQ num_bits - C_DOUT_WIDTH; + + + /*********************************/ + // FIFO is FULL + /*********************************/ + end else if (num_write_words >= C_FIFO_WR_DEPTH) + begin + //no write attempted + ideal_wr_ack <= #`TCQ 0; + + //FIFO is leaving FULL, but is still ALMOST_FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b1; + + //Read successful + ideal_valid <= #`TCQ 1'b1; + + //Not near empty + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + //Read from the FIFO + read_fifo; + num_bits <= #`TCQ num_bits - C_DOUT_WIDTH; + + /*********************************/ + //If the FIFO is not near EMPTY or FULL + /*********************************/ + end else begin + //no write attemped + ideal_wr_ack <= #`TCQ 0; + + //Not near empty + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //Read successful + ideal_valid <= #`TCQ 1'b1; + + //Not near empty + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + //Read from the FIFO + read_fifo; + num_bits <= #`TCQ num_bits - C_DOUT_WIDTH; + + + end // average read + + + /******************************************************************/ + // Synchronous FIFO Condition #3 : Reading and writing + /******************************************************************/ + end else if (WR_EN & RD_EN) begin + + /*********************************/ + // FIFO is FULL + /*********************************/ + if (num_write_words >= C_FIFO_WR_DEPTH) begin + + ideal_wr_ack <= #`TCQ 0; + + //Read will be successful, so FIFO will leave FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b1; + + //Read successful + ideal_valid <= #`TCQ 1'b1; + + //Not near empty + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + //Read from the FIFO + read_fifo; + num_bits <= #`TCQ num_bits - C_DOUT_WIDTH; + + + /*********************************/ + // FIFO is reporting FULL, but it is empty + // (This is a special case, when coming out of RST + /*********************************/ + end else if ((num_write_words == 0) && (ideal_full == 1'b1)) begin + + ideal_wr_ack <= #`TCQ 0; + + //Read will be successful, so FIFO will leave FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //Read unsuccessful + ideal_valid <= #`TCQ 1'b0; + + //Report empty condition + ideal_empty <= #`TCQ 1'b1; + ideal_almost_empty <= #`TCQ 1'b1; + + //Do not read from empty FIFO + // Read from the FIFO + + + /*********************************/ + //If the FIFO is one from full + /*********************************/ + end else if (num_write_words == C_FIFO_WR_DEPTH-1) begin + + //Write successful + ideal_wr_ack <= #`TCQ 1; + + //FIFO will remain ALMOST_FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b1; + + // put the data into the FIFO + write_fifo; + + //Read successful + ideal_valid <= #`TCQ 1'b1; + + //Not near empty + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + //Read from the FIFO + read_fifo; + num_bits <= #`TCQ num_bits + C_DIN_WIDTH - C_DOUT_WIDTH; + + /*********************************/ + //If the FIFO is ALMOST EMPTY + /*********************************/ + end else if (num_read_words == 1) begin + + //Write successful + ideal_wr_ack <= #`TCQ 1; + + // Not near FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + // put the data into the FIFO + write_fifo; + + //Read successful + ideal_valid <= #`TCQ 1'b1; + + //FIFO will stay ALMOST_EMPTY + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b1; + + //Read from the FIFO + read_fifo; + num_bits <= #`TCQ num_bits + C_DIN_WIDTH - C_DOUT_WIDTH; + + + /*********************************/ + //If the FIFO is EMPTY + /*********************************/ + end else if (num_read_words == 0) begin + + //Write successful + ideal_wr_ack <= #`TCQ 1; + + // Not near FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + // put the data into the FIFO + write_fifo; + + //Read will fail + ideal_valid <= #`TCQ 1'b0; + + //FIFO will leave EMPTY + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b1; + + // No read + num_bits <= #`TCQ num_bits + C_DIN_WIDTH; + + + /*********************************/ + //If the FIFO is not near EMPTY or FULL + /*********************************/ + end else begin + + //Write successful + ideal_wr_ack <= #`TCQ 1; + + // Not near FULL + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + // put the data into the FIFO + write_fifo; + + //Read successful + ideal_valid <= #`TCQ 1'b1; + + // Not near EMPTY + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + //Read from the FIFO + read_fifo; + num_bits <= #`TCQ num_bits + C_DIN_WIDTH - C_DOUT_WIDTH; + + end // average case + + /******************************************************************/ + // Synchronous FIFO Condition #4 : Not reading or writing + /******************************************************************/ + end else begin + + /*********************************/ + // FIFO is FULL + /*********************************/ + if (num_write_words >= C_FIFO_WR_DEPTH) begin + + //No write + ideal_wr_ack <= #`TCQ 0; + ideal_full <= #`TCQ 1'b1; + ideal_almost_full <= #`TCQ 1'b1; + + //No read + ideal_valid <= #`TCQ 1'b0; + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + //No change to memory + + /*********************************/ + //If the FIFO is one from full + /*********************************/ + end else if (num_write_words == C_FIFO_WR_DEPTH-1) begin + + //No write + ideal_wr_ack <= #`TCQ 0; + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b1; + + //No read + ideal_valid <= #`TCQ 1'b0; + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + //No change to memory + + /*********************************/ + //If the FIFO is ALMOST EMPTY + /*********************************/ + end else if (num_read_words == 1) begin + //No write + ideal_wr_ack <= #`TCQ 0; + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //No read + ideal_valid <= #`TCQ 1'b0; + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b1; + + //No change to memory + + end // almost empty + + + /*********************************/ + //If the FIFO is EMPTY + /*********************************/ + else if (num_read_words == 0) + begin + //No write + ideal_wr_ack <= #`TCQ 0; + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //No read + ideal_valid <= #`TCQ 1'b0; + ideal_empty <= #`TCQ 1'b1; + ideal_almost_empty <= #`TCQ 1'b1; + + //No change to memory + + /*********************************/ + //If the FIFO is not near EMPTY or FULL + /*********************************/ + end else begin + + //No write + ideal_wr_ack <= #`TCQ 0; + ideal_full <= #`TCQ 1'b0; + ideal_almost_full <= #`TCQ 1'b0; + + //No read + ideal_valid <= #`TCQ 1'b0; + ideal_empty <= #`TCQ 1'b0; + ideal_almost_empty <= #`TCQ 1'b0; + + //No change to memory + + end // average case + + end // neither reading or writing + + num_read_words_q <= #`TCQ num_read_words; + num_write_words_q <= #`TCQ num_write_words; + + end //normal operating conditions + end + + end // block: gen_fifo + + + always @(posedge CLK or posedge RST_FULL_FF) begin : gen_fifo_p + + /****** Reset fifo - Async Reset****************************************/ + //The latency of de-assertion of the flags is reduced by 1 to be + // consistent with the core. + if (RST_FULL_FF) begin + ideal_prog_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + ideal_prog_empty <= #`TCQ 1'b1; + prog_full_d <= #`TCQ C_FULL_FLAGS_RST_VAL; + prog_empty_d <= #`TCQ 1'b1; + + end else begin + if (srst_i) begin + //SRST is available only for Sync BRAM and Sync DRAM. Not for SSHFT. + if (C_MEMORY_TYPE == 1 || C_MEMORY_TYPE == 2 || C_MEMORY_TYPE == 3) begin + ideal_prog_empty <= #`TCQ 1'b1; + prog_empty_d <= #`TCQ 1'b1; + ideal_prog_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + prog_full_d <= #`TCQ C_FULL_FLAGS_RST_VAL; + end + end else if ((srst_i_d1 || srst_i_d2) && (C_FULL_FLAGS_RST_VAL == 1)) begin + ideal_prog_full <= #`TCQ C_FULL_FLAGS_RST_VAL; + prog_full_d <= #`TCQ C_FULL_FLAGS_RST_VAL; + end else begin + + /*************************************************************** + * Programmable FULL flags + ****************************************************************/ + //calculation for standard fifo and latency =2 + if (! (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) ) begin + //Single constant threshold + if (C_PROG_FULL_TYPE == 1) begin + if ((num_write_words >= C_PROG_FULL_THRESH_ASSERT_VAL-1) + && WR_EN && !RD_EN) begin + prog_full_d <= #`TCQ 1'b1; + end else if (((num_write_words == C_PROG_FULL_THRESH_ASSERT_VAL) + && RD_EN && !WR_EN) || (RST_FULL_GEN)) begin + prog_full_d <= #`TCQ 1'b0; + end + + //Dual constant thresholds + end else if (C_PROG_FULL_TYPE == 2) begin + if ((num_write_words == C_PROG_FULL_THRESH_ASSERT_VAL-1) + && WR_EN && !RD_EN) begin + prog_full_d <= #`TCQ 1'b1; + end else if ((num_write_words == C_PROG_FULL_THRESH_NEGATE_VAL) + && RD_EN && !WR_EN) begin + prog_full_d <= #`TCQ 1'b0; + end + + //Single input threshold + end else if (C_PROG_FULL_TYPE == 3) begin + if ((num_write_words == PROG_FULL_THRESH-1) + && WR_EN && !RD_EN) begin + prog_full_d <= #`TCQ 1'b1; + end else if ((num_write_words == PROG_FULL_THRESH) + && !WR_EN && RD_EN) begin + prog_full_d <= #`TCQ 1'b0; + end else if (num_write_words >= PROG_FULL_THRESH) begin + prog_full_d <= #`TCQ 1'b1; + end else if (num_write_words < PROG_FULL_THRESH) begin + prog_full_d <= #`TCQ 1'b0; + end + + //Dual input thresholds + end else begin + if ((num_write_words == PROG_FULL_THRESH_ASSERT-1) + && WR_EN && !RD_EN) begin + prog_full_d <= #`TCQ 1'b1; + end else if ((num_write_words == PROG_FULL_THRESH_NEGATE) + && !WR_EN && RD_EN)begin + prog_full_d <= #`TCQ 1'b0; + end else if (num_write_words >= PROG_FULL_THRESH_ASSERT) begin + prog_full_d <= #`TCQ 1'b1; + end else if (num_write_words < PROG_FULL_THRESH_NEGATE) begin + prog_full_d <= #`TCQ 1'b0; + end + end + end // (~ (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) ) + + + //calculation for FWFT fifo + if (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) begin + if (C_PROG_FULL_TYPE == 1) begin + if ((num_write_words >= C_PROG_FULL_THRESH_ASSERT_VAL-1 - 2) + && WR_EN && !RD_EN) begin + prog_full_d <= #`TCQ 1'b1; + end else if (((num_write_words == C_PROG_FULL_THRESH_ASSERT_VAL - 2) + && RD_EN && !WR_EN) || (RST_FULL_GEN)) begin + prog_full_d <= #`TCQ 1'b0; + end + + //Dual constant thresholds + end else if (C_PROG_FULL_TYPE == 2) begin + if ((num_write_words == C_PROG_FULL_THRESH_ASSERT_VAL-1 - 2) + && WR_EN && !RD_EN) begin + prog_full_d <= #`TCQ 1'b1; + end else if ((num_write_words == C_PROG_FULL_THRESH_NEGATE_VAL - 2) + && RD_EN && !WR_EN) begin + prog_full_d <= #`TCQ 1'b0; + end + + //Single input threshold + end else if (C_PROG_FULL_TYPE == 3) begin + if ((num_write_words == PROG_FULL_THRESH-1 - 2) + && WR_EN && !RD_EN) begin + prog_full_d <= #`TCQ 1'b1; + end else if ((num_write_words == PROG_FULL_THRESH - 2) + && !WR_EN && RD_EN) begin + prog_full_d <= #`TCQ 1'b0; + end else if (num_write_words >= PROG_FULL_THRESH - 2) begin + prog_full_d <= #`TCQ 1'b1; + end else if (num_write_words < PROG_FULL_THRESH - 2) begin + prog_full_d <= #`TCQ 1'b0; + end + + //Dual input thresholds + end else begin + if ((num_write_words == PROG_FULL_THRESH_ASSERT-1 - 2) + && WR_EN && !RD_EN) begin + prog_full_d <= #`TCQ 1'b1; + end else if ((num_write_words == PROG_FULL_THRESH_NEGATE - 2) + && !WR_EN && RD_EN)begin + prog_full_d <= #`TCQ 1'b0; + end else if (num_write_words >= PROG_FULL_THRESH_ASSERT - 2) begin + prog_full_d <= #`TCQ 1'b1; + end else if (num_write_words < PROG_FULL_THRESH_NEGATE - 2) begin + prog_full_d <= #`TCQ 1'b0; + end + end + end // (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) + + /***************************************************************** + * Programmable EMPTY flags + ****************************************************************/ + //calculation for standard fifo and latency = 2 + if (! (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) ) begin + //Single constant threshold + if (C_PROG_EMPTY_TYPE == 1) begin + if ((num_read_words == C_PROG_EMPTY_THRESH_ASSERT_VAL+1) + && RD_EN && !WR_EN) begin + prog_empty_d <= #`TCQ 1'b1; + end else if ((num_read_words == C_PROG_EMPTY_THRESH_ASSERT_VAL) + && WR_EN && !RD_EN) begin + prog_empty_d <= #`TCQ 1'b0; + end + //Dual constant thresholds + end else if (C_PROG_EMPTY_TYPE == 2) begin + if ((num_read_words == C_PROG_EMPTY_THRESH_ASSERT_VAL+1) + && RD_EN && !WR_EN) begin + prog_empty_d <= #`TCQ 1'b1; + end else if ((num_read_words == C_PROG_EMPTY_THRESH_NEGATE_VAL) + && !RD_EN && WR_EN) begin + prog_empty_d <= #`TCQ 1'b0; + end + + //Single input threshold + end else if (C_PROG_EMPTY_TYPE == 3) begin + if ((num_read_words == PROG_EMPTY_THRESH+1) + && RD_EN && !WR_EN) begin + prog_empty_d <= #`TCQ 1'b1; + end else if ((num_read_words == PROG_EMPTY_THRESH) + && !RD_EN && WR_EN) begin + prog_empty_d <= #`TCQ 1'b0; + end else if (num_read_words <= PROG_EMPTY_THRESH) begin + prog_empty_d <= #`TCQ 1'b1; + end else if (num_read_words > PROG_EMPTY_THRESH)begin + prog_empty_d <= #`TCQ 1'b0; + end + + //Dual input thresholds + end else begin + if (num_read_words <= PROG_EMPTY_THRESH_ASSERT) begin + prog_empty_d <= #`TCQ 1'b1; + end else if ((num_read_words == PROG_EMPTY_THRESH_ASSERT+1) + && RD_EN && !WR_EN) begin + prog_empty_d <= #`TCQ 1'b1; + end else if (num_read_words > PROG_EMPTY_THRESH_NEGATE)begin + prog_empty_d <= #`TCQ 1'b0; + end else if ((num_read_words == PROG_EMPTY_THRESH_NEGATE) + && !RD_EN && WR_EN) begin + prog_empty_d <= #`TCQ 1'b0; + end + end + end // (~ (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) ) + + //calculation for FWFT fifo + if (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) begin + //Single constant threshold + if (C_PROG_EMPTY_TYPE == 1) begin + if ((num_read_words == C_PROG_EMPTY_THRESH_ASSERT_VAL+1 - 2) + && RD_EN && !WR_EN) begin + prog_empty_d <= #`TCQ 1'b1; + end else if ((num_read_words == C_PROG_EMPTY_THRESH_ASSERT_VAL - 2) + && WR_EN && !RD_EN) begin + prog_empty_d <= #`TCQ 1'b0; + end + //Dual constant thresholds + end else if (C_PROG_EMPTY_TYPE == 2) begin + if ((num_read_words == C_PROG_EMPTY_THRESH_ASSERT_VAL+1 - 2) + && RD_EN && !WR_EN) begin + prog_empty_d <= #`TCQ 1'b1; + end else if ((num_read_words == C_PROG_EMPTY_THRESH_NEGATE_VAL - 2) + && !RD_EN && WR_EN) begin + prog_empty_d <= #`TCQ 1'b0; + end + + //Single input threshold + end else if (C_PROG_EMPTY_TYPE == 3) begin + if ((num_read_words == PROG_EMPTY_THRESH+1 - 2) + && RD_EN && !WR_EN) begin + prog_empty_d <= #`TCQ 1'b1; + end else if ((num_read_words == PROG_EMPTY_THRESH - 2) + && !RD_EN && WR_EN) begin + prog_empty_d <= #`TCQ 1'b0; + end else if (num_read_words <= PROG_EMPTY_THRESH - 2) begin + prog_empty_d <= #`TCQ 1'b1; + end else if (num_read_words > PROG_EMPTY_THRESH - 2)begin + prog_empty_d <= #`TCQ 1'b0; + end + + //Dual input thresholds + end else begin + if (num_read_words <= PROG_EMPTY_THRESH_ASSERT - 2) begin + prog_empty_d <= #`TCQ 1'b1; + end else if ((num_read_words == PROG_EMPTY_THRESH_ASSERT+1 - 2) + && RD_EN && !WR_EN) begin + prog_empty_d <= #`TCQ 1'b1; + end else if (num_read_words > PROG_EMPTY_THRESH_NEGATE - 2)begin + prog_empty_d <= #`TCQ 1'b0; + end else if ((num_read_words == PROG_EMPTY_THRESH_NEGATE - 2) + && !RD_EN && WR_EN) begin + prog_empty_d <= #`TCQ 1'b0; + end + end + end // (~ (C_PRELOAD_REGS==1 && C_PRELOAD_LATENCY==0) ) + + ideal_prog_empty <= prog_empty_d; + if (RST_FULL_GEN) begin + ideal_prog_full <= #`TCQ 1'b0; + prog_full_d <= #`TCQ 1'b0; + end else begin + ideal_prog_full <= #`TCQ prog_full_d; + end + + end //if (srst_i) begin + end //if (rst_i) begin + end //always @(posedge CLK or posedge rst_i) begin : gen_fifo_p +endmodule // fifo_generator_v6_1_bhv_ver_ss + + + +/************************************************************************** + * First-Word Fall-Through module (preload 0) + **************************************************************************/ +module fifo_generator_v6_1_bhv_ver_preload0 + ( + RD_CLK, + RD_RST, + SRST, + RD_EN, + FIFOEMPTY, + FIFODATA, + FIFOSBITERR, + FIFODBITERR, + USERDATA, + USERVALID, + USERUNDERFLOW, + USEREMPTY, + USERALMOSTEMPTY, + RAMVALID, + FIFORDEN, + USERSBITERR, + USERDBITERR + ); + + parameter C_DOUT_RST_VAL = ""; + parameter C_DOUT_WIDTH = 8; + parameter C_HAS_RST = 0; + parameter C_ENABLE_RST_SYNC = 0; + parameter C_HAS_SRST = 0; + parameter C_USE_DOUT_RST = 0; + parameter C_USE_ECC = 0; + parameter C_USERVALID_LOW = 0; + parameter C_USERUNDERFLOW_LOW = 0; + parameter C_MEMORY_TYPE = 0; + + //Inputs + input RD_CLK; + input RD_RST; + input SRST; + input RD_EN; + input FIFOEMPTY; + input [C_DOUT_WIDTH-1:0] FIFODATA; + input FIFOSBITERR; + input FIFODBITERR; + + //Outputs + output [C_DOUT_WIDTH-1:0] USERDATA; + output USERVALID; + output USERUNDERFLOW; + output USEREMPTY; + output USERALMOSTEMPTY; + output RAMVALID; + output FIFORDEN; + output USERSBITERR; + output USERDBITERR; + + //Inputs + wire RD_CLK; + wire RD_RST; + wire RD_EN; + wire FIFOEMPTY; + wire [C_DOUT_WIDTH-1:0] FIFODATA; + wire FIFOSBITERR; + wire FIFODBITERR; + + //Outputs + reg [C_DOUT_WIDTH-1:0] USERDATA; + wire USERVALID; + wire USERUNDERFLOW; + wire USEREMPTY; + wire USERALMOSTEMPTY; + wire RAMVALID; + wire FIFORDEN; + reg USERSBITERR; + reg USERDBITERR; + + //Internal signals + wire preloadstage1; + wire preloadstage2; + reg ram_valid_i; + reg read_data_valid_i; + wire ram_regout_en; + wire ram_rd_en; + reg empty_i = 1'b1; + reg empty_q = 1'b1; + reg rd_en_q = 1'b0; + reg almost_empty_i = 1'b1; + reg almost_empty_q = 1'b1; + wire rd_rst_i; + wire srst_i; + + +/************************************************************************* +* FUNCTIONS +*************************************************************************/ + + /************************************************************************* + * hexstr_conv + * Converts a string of type hex to a binary value (for C_DOUT_RST_VAL) + ***********************************************************************/ + function [C_DOUT_WIDTH-1:0] hexstr_conv; + input [(C_DOUT_WIDTH*8)-1:0] def_data; + + integer index,i,j; + reg [3:0] bin; + + begin + index = 0; + hexstr_conv = 'b0; + for( i=C_DOUT_WIDTH-1; i>=0; i=i-1 ) + begin + case (def_data[7:0]) + 8'b00000000 : + begin + bin = 4'b0000; + i = -1; + end + 8'b00110000 : bin = 4'b0000; + 8'b00110001 : bin = 4'b0001; + 8'b00110010 : bin = 4'b0010; + 8'b00110011 : bin = 4'b0011; + 8'b00110100 : bin = 4'b0100; + 8'b00110101 : bin = 4'b0101; + 8'b00110110 : bin = 4'b0110; + 8'b00110111 : bin = 4'b0111; + 8'b00111000 : bin = 4'b1000; + 8'b00111001 : bin = 4'b1001; + 8'b01000001 : bin = 4'b1010; + 8'b01000010 : bin = 4'b1011; + 8'b01000011 : bin = 4'b1100; + 8'b01000100 : bin = 4'b1101; + 8'b01000101 : bin = 4'b1110; + 8'b01000110 : bin = 4'b1111; + 8'b01100001 : bin = 4'b1010; + 8'b01100010 : bin = 4'b1011; + 8'b01100011 : bin = 4'b1100; + 8'b01100100 : bin = 4'b1101; + 8'b01100101 : bin = 4'b1110; + 8'b01100110 : bin = 4'b1111; + default : + begin + bin = 4'bx; + end + endcase + for( j=0; j<4; j=j+1) + begin + if ((index*4)+j < C_DOUT_WIDTH) + begin + hexstr_conv[(index*4)+j] = bin[j]; + end + end + index = index + 1; + def_data = def_data >> 8; + end + end + endfunction + + + //************************************************************************* + // Set power-on states for regs + //************************************************************************* + initial begin + ram_valid_i = 1'b0; + read_data_valid_i = 1'b0; + USERDATA = hexstr_conv(C_DOUT_RST_VAL); + USERSBITERR = 1'b0; + USERDBITERR = 1'b0; + end //initial + + //*************************************************************************** + // connect up optional reset + //*************************************************************************** + assign rd_rst_i = (C_HAS_RST == 1 || C_ENABLE_RST_SYNC == 0) ? RD_RST : 0; + assign srst_i = C_HAS_SRST ? SRST : 0; + + + //*************************************************************************** + // preloadstage2 indicates that stage2 needs to be updated. This is true + // whenever read_data_valid is false, and RAM_valid is true. + //*************************************************************************** + assign preloadstage2 = ram_valid_i & (~read_data_valid_i | RD_EN); + + //*************************************************************************** + // preloadstage1 indicates that stage1 needs to be updated. This is true + // whenever the RAM has data (RAM_EMPTY is false), and either RAM_Valid is + // false (indicating that Stage1 needs updating), or preloadstage2 is active + // (indicating that Stage2 is going to update, so Stage1, therefore, must + // also be updated to keep it valid. + //*************************************************************************** + assign preloadstage1 = ((~ram_valid_i | preloadstage2) & ~FIFOEMPTY); + + //*************************************************************************** + // Calculate RAM_REGOUT_EN + // The output registers are controlled by the ram_regout_en signal. + // These registers should be updated either when the output in Stage2 is + // invalid (preloadstage2), OR when the user is reading, in which case the + // Stage2 value will go invalid unless it is replenished. + //*************************************************************************** + assign ram_regout_en = preloadstage2; + + //*************************************************************************** + // Calculate RAM_RD_EN + // RAM_RD_EN will be asserted whenever the RAM needs to be read in order to + // update the value in Stage1. + // One case when this happens is when preloadstage1=true, which indicates + // that the data in Stage1 or Stage2 is invalid, and needs to automatically + // be updated. + // The other case is when the user is reading from the FIFO, which + // guarantees that Stage1 or Stage2 will be invalid on the next clock + // cycle, unless it is replinished by data from the memory. So, as long + // as the RAM has data in it, a read of the RAM should occur. + //*************************************************************************** + assign ram_rd_en = (RD_EN & ~FIFOEMPTY) | preloadstage1; + + //*************************************************************************** + // Calculate RAMVALID_P0_OUT + // RAMVALID_P0_OUT indicates that the data in Stage1 is valid. + // + // If the RAM is being read from on this clock cycle (ram_rd_en=1), then + // RAMVALID_P0_OUT is certainly going to be true. + // If the RAM is not being read from, but the output registers are being + // updated to fill Stage2 (ram_regout_en=1), then Stage1 will be emptying, + // therefore causing RAMVALID_P0_OUT to be false. + // Otherwise, RAMVALID_P0_OUT will remain unchanged. + //*************************************************************************** + // PROCESS regout_valid + always @ (posedge RD_CLK or posedge rd_rst_i) begin + if (rd_rst_i) begin + // asynchronous reset (active high) + ram_valid_i <= #`TCQ 1'b0; + end else begin + if (srst_i) begin + // synchronous reset (active high) + ram_valid_i <= #`TCQ 1'b0; + end else begin + if (ram_rd_en == 1'b1) begin + ram_valid_i <= #`TCQ 1'b1; + end else begin + if (ram_regout_en == 1'b1) + ram_valid_i <= #`TCQ 1'b0; + else + ram_valid_i <= #`TCQ ram_valid_i; + end + end //srst_i + end //rd_rst_i + end //always + + //*************************************************************************** + // Calculate READ_DATA_VALID + // READ_DATA_VALID indicates whether the value in Stage2 is valid or not. + // Stage2 has valid data whenever Stage1 had valid data and + // ram_regout_en_i=1, such that the data in Stage1 is propogated + // into Stage2. + //*************************************************************************** + always @ (posedge RD_CLK or posedge rd_rst_i) begin + if (rd_rst_i) + read_data_valid_i <= #`TCQ 1'b0; + else if (srst_i) + read_data_valid_i <= #`TCQ 1'b0; + else + read_data_valid_i <= #`TCQ ram_valid_i | (read_data_valid_i & ~RD_EN); + end //always + + + //************************************************************************** + // Calculate EMPTY + // Defined as the inverse of READ_DATA_VALID + // + // Description: + // + // If read_data_valid_i indicates that the output is not valid, + // and there is no valid data on the output of the ram to preload it + // with, then we will report empty. + // + // If there is no valid data on the output of the ram and we are + // reading, then the FIFO will go empty. + // + //************************************************************************** + always @ (posedge RD_CLK or posedge rd_rst_i) begin + if (rd_rst_i) begin + // asynchronous reset (active high) + empty_i <= #`TCQ 1'b1; + end else begin + if (srst_i) begin + // synchronous reset (active high) + empty_i <= #`TCQ 1'b1; + end else begin + // rising clock edge + empty_i <= #`TCQ (~ram_valid_i & ~read_data_valid_i) | (~ram_valid_i & RD_EN); + end + end + end //always + + // Register RD_EN from user to calculate USERUNDERFLOW. + // Register empty_i to calculate USERUNDERFLOW. + always @ (posedge RD_CLK) begin + rd_en_q <= #`TCQ RD_EN; + empty_q <= #`TCQ empty_i; + end //always + + + //*************************************************************************** + // Calculate user_almost_empty + // user_almost_empty is defined such that, unless more words are written + // to the FIFO, the next read will cause the FIFO to go EMPTY. + // + // In most cases, whenever the output registers are updated (due to a user + // read or a preload condition), then user_almost_empty will update to + // whatever RAM_EMPTY is. + // + // The exception is when the output is valid, the user is not reading, and + // Stage1 is not empty. In this condition, Stage1 will be preloaded from the + // memory, so we need to make sure user_almost_empty deasserts properly under + // this condition. + //*************************************************************************** + always @ (posedge RD_CLK or posedge rd_rst_i) + begin + if (rd_rst_i) begin // asynchronous reset (active high) + almost_empty_i <= #`TCQ 1'b1; + almost_empty_q <= #`TCQ 1'b1; + end else begin // rising clock edge + if (srst_i) begin // synchronous reset (active high) + almost_empty_i <= #`TCQ 1'b1; + almost_empty_q <= #`TCQ 1'b1; + end else begin + if ((ram_regout_en) | (~FIFOEMPTY & read_data_valid_i & ~RD_EN)) begin + almost_empty_i <= #`TCQ FIFOEMPTY; + end + almost_empty_q <= #`TCQ empty_i; + end + end + end //always + + + assign USEREMPTY = empty_i; + assign USERALMOSTEMPTY = almost_empty_i; + assign FIFORDEN = ram_rd_en; + assign RAMVALID = ram_valid_i; + assign USERVALID = C_USERVALID_LOW ? ~read_data_valid_i : read_data_valid_i; + assign USERUNDERFLOW = C_USERUNDERFLOW_LOW ? ~(empty_q & rd_en_q) : empty_q & rd_en_q; + + // BRAM resets synchronously + always @ (posedge RD_CLK) + begin + if (rd_rst_i || srst_i) begin + if (C_USE_DOUT_RST == 1 && C_MEMORY_TYPE < 2) + USERDATA <= #`TCQ hexstr_conv(C_DOUT_RST_VAL); + end + end //always + + + always @ (posedge RD_CLK or posedge rd_rst_i) + begin + if (rd_rst_i) begin //asynchronous reset (active high) + if (C_USE_ECC == 0) begin // Reset S/DBITERR only if ECC is OFF + USERSBITERR <= #`TCQ 0; + USERDBITERR <= #`TCQ 0; + end + // DRAM resets asynchronously + if (C_USE_DOUT_RST == 1 && C_MEMORY_TYPE == 2) //asynchronous reset (active high) + USERDATA <= #`TCQ hexstr_conv(C_DOUT_RST_VAL); + end else begin // rising clock edge + if (srst_i) begin + if (C_USE_ECC == 0) begin // Reset S/DBITERR only if ECC is OFF + USERSBITERR <= #`TCQ 0; + USERDBITERR <= #`TCQ 0; + end + if (C_USE_DOUT_RST == 1 && C_MEMORY_TYPE == 2) + USERDATA <= #`TCQ hexstr_conv(C_DOUT_RST_VAL); + end else begin + if (ram_regout_en) begin + USERDATA <= #`TCQ FIFODATA; + USERSBITERR <= #`TCQ FIFOSBITERR; + USERDBITERR <= #`TCQ FIFODBITERR; + end + end + end + end //always + +endmodule + -- cgit v1.2.3