Xilinx ISE中DDR3 IP核的使用（1）
ISE 中mig IP的调用与仿真环境的搭建
- 项目简介简述
- MIG IP建立的步骤
- MIG自带示例工程的搭建
- MIG 仿真环境的搭建
- 仿真结果
- 结束语
项目简介简述
Xilinx的MIG IP核是官方给出的DDR驱动，是一个FPGA工程师由入门更近一步必学的一个IP，因为FPGA本身的优势就是吞吐量特别大，而这一定伴随着内存的操作。Xlinx的软件版本主要有ISE与vivado两个软件，两个软件MIG的使用方法又不一样，接下来，我们将分别介绍两种软件MIG IP的使用。本篇文章，我们主要讲解以下内容：
1、使用ISE软件建立一个MIG IP核
2、建立一个MIG IP完整的仿真环境，以便于我们接下来的调试
MIG IP建立的步骤
熟悉我博客的同学应该知道，我对一些软件的使用都没有过多的介绍，只是给出了时序图与代码供大家自己理解，但是由于MIG IP比较复杂，这里我们给出详细的MIG调用流程。
1、首先在1处输入MIG
2、双击标号2的MIG IP核
1、首先对比以下1处的设置信息，防止出错
2、点击2出的Next
1、其中上面1为建立一个新的MIG IP核，2为官方开发板的选择，3为更改一个已存在的MIG IP，在本次实验中我们选择1建立一个新的MIG IP核
2、点击4Next，进行下一步
1、其中1中的选项勾选了代表我们的这个IP不光只对该型号有用，也适用于选中的型号
2、这里我们不勾选1中的选项，直接点击2Next
1、其中1为使能AXI接口，该接口在7系列的非常常见，在这里我们不选择，AXI协议我们之后也会有文章来讲解，2会扩展外设的使用范围，我们这里不需要，也不选择，3是说明该FPGA芯片中两个bank中含有MCB硬件，我们查看具体的FPGA硬件板卡DDR连接在哪个bank，这里我们选择了bank3。
2、在3出下拉选择DDR3 SDRAM，然后点击Next
1、其中1有两个含义，一个是DDR3硬件的时钟频率，另一个是MIG的输入参考频率，2是对应的DDR3硬件的型号
2、在选择对应的型号之后，点击Next
1、这里1、2是与硬件的电阻情况有关，正常情况下默认即可
2、3为使能自动刷新操作，不需要我们再个MIG相应的刷新命令，这里选择使能该操作，点击Next
1、这里1是ISE比vivado中好的地方，就是说可以选择多通道模式，但是vivado中不可以，需要自己编写相应的程序，这里我们选择双通道可读可写64位模式，并且打上对号
2、2是MIG地址对应到DDR硬件地址中的顺序，这里选择第二个，然后点击Next
1、这里是两个通道同时有读写指令的情况下的先执行哪一个通道的顺序问题，这里我们使用默认的Round策略即可，然后点击Next。
1、其中1位硬件电路中的DDR与FPGA相连的电阻管脚，与2、3对应，然后查看开发板硬件手册找到RZQ、ZTQ两个引脚与FPGA连接的管脚，并且写在对应的2、3上面
2、4使能代表给添加了一些测试文件供我们调试，我们这里不使能，想调试我们自己添加ila进行调试
3、5是时钟的形式，这里选择单端即可
1、上面是选中的总结，点击Next
1、选择接受该协议，然后点击Next
然后一路Next，最后生成MIG IP核即可。到此为止，我们建立了一个完整新的MIG IP，并且知道了MIG IP核调用过程中每个选项所代表的意义。
MIG自带示例工程的搭建
我们班接下来要对该我们的MIG IP核搭建仿真环境，为了掌握仿真环境的搭建，我们先对MIG生成的示例工程进行搭建，然后再搭建我们的MIG仿真环境，因为其中的代码都是借鉴的示例工程中的代码，这里我们也给出了学习一个新的IP的完整流程。
首先找到相应的示例工程所存储的文件，如下：
1、这里ISE与VIVADO不同，这个示例工程需要我们自己建立，这里新建一个工程，将上述的文件添加进去。
2、注意要添加的文件都在sim与rtl（里面的文件全部加入）中，如下图：
然后进行Modelsim仿真，这里既然做到了DDR应该就都熟悉了，不再多说。仿真的结果如下：
仿真出现上面两种界面，说明了我们示例工程的仿真环境搭建成功，接下来我们将利用这个示例工程搭建我们的MIG IP核的工程，里面具体很多代码都是参考的该示例工程。
MIG 仿真环境的搭建
这里我们将给出代码，大家可以对比一下代码与上面示例工程的代码，在仿真模型的处理上几乎一样。
这里注意一点为了加快仿真速度，将上面的C3_SIMULATION改成TURE，
ddr3_top模块：
`timescale 1ns / 1ps
// *********************************************************************************
// Project Name : OSXXXX
// Author : zhangningning
// Email : [email protected]
// Website :
// Module Name : ddr3_top.v
// Create Time : 2020-02-21 22:56:59
// Editor : sublime text3, tab size (4)
// CopyRight(c) : All Rights Reserved
//
// *********************************************************************************
// Modification History:
// Date By Version Change Description
// -----------------------------------------------------------------------
// XXXX zhangningning 1.0 Original
//
// *********************************************************************************
module ddr3_top(
// DDR3 Interfaces
inout [15:0] mcb3_dram_dq ,
output wire [12:0] mcb3_dram_a ,
output wire [02:0] mcb3_dram_ba ,
output wire mcb3_dram_ras_n ,
output wire mcb3_dram_cas_n ,
output wire mcb3_dram_we_n ,
output wire mcb3_dram_odt ,
output wire mcb3_dram_reset_n ,
output wire mcb3_dram_cke ,
output wire mcb3_dram_dm ,
inout mcb3_dram_udqs ,
inout mcb3_dram_udqs_n ,
inout mcb3_rzq ,
inout mcb3_zio ,
output wire mcb3_dram_udm ,
input c3_sys_clk ,
input c3_sys_rst_i ,
inout mcb3_dram_dqs ,
inout mcb3_dram_dqs_n ,
output wire mcb3_dram_ck ,
output wire mcb3_dram_ck_n
);
//========================================================================================\
//**************Define Parameter and Internal Signals**********************************
//========================================================================================/
//========================================================================================\
//************** Main Code **********************************
//========================================================================================/
mig_39_2 # (
.C3_P0_MASK_SIZE (8 ),
.C3_P0_DATA_PORT_SIZE (64 ),
.C3_P1_MASK_SIZE (8 ),
.C3_P1_DATA_PORT_SIZE (64 ),
.DEBUG_EN (0 ),
.C3_MEMCLK_PERIOD (3200 ),
.C3_CALIB_SOFT_IP ("TRUE" ),
.C3_SIMULATION ("TURE" ),
.C3_RST_ACT_LOW (0 ),
.C3_INPUT_CLK_TYPE ("SINGLE_ENDED" ),
.C3_MEM_ADDR_ORDER ("BANK_ROW_COLUMN" ),
.C3_NUM_DQ_PINS (16 ),
.C3_MEM_ADDR_WIDTH (13 ),
.C3_MEM_BANKADDR_WIDTH (3 )
)
u_mig_39_2 (
.c3_sys_clk (c3_sys_clk ),
.c3_sys_rst_i (c3_sys_rst_i ),
.mcb3_dram_dq (mcb3_dram_dq ),
.mcb3_dram_a (mcb3_dram_a ),
.mcb3_dram_ba (mcb3_dram_ba ),
.mcb3_dram_ras_n (mcb3_dram_ras_n ),
.mcb3_dram_cas_n (mcb3_dram_cas_n ),
.mcb3_dram_we_n (mcb3_dram_we_n ),
.mcb3_dram_odt (mcb3_dram_odt ),
.mcb3_dram_cke (mcb3_dram_cke ),
.mcb3_dram_ck (mcb3_dram_ck ),
.mcb3_dram_ck_n (mcb3_dram_ck_n ),
.mcb3_dram_dqs (mcb3_dram_dqs ),
.mcb3_dram_dqs_n (mcb3_dram_dqs_n ),
.mcb3_dram_udqs (mcb3_dram_udqs ), // for X16 parts
.mcb3_dram_udqs_n (mcb3_dram_udqs_n ), // for X16 parts
.mcb3_dram_udm (mcb3_dram_udm ), // for X16 parts
.mcb3_dram_dm (mcb3_dram_dm ),
.mcb3_dram_reset_n (mcb3_dram_reset_n ),
.mcb3_rzq (mcb3_rzq ),
.mcb3_zio (mcb3_zio ),
.c3_clk0 (c3_clk0 ),
.c3_rst0 (c3_rst0 ),
.c3_calib_done (c3_calib_done ),
.c3_p0_cmd_clk (c3_p0_cmd_clk ),
.c3_p0_cmd_en (c3_p0_cmd_en ),
.c3_p0_cmd_instr (c3_p0_cmd_instr ),
.c3_p0_cmd_bl (c3_p0_cmd_bl ),
.c3_p0_cmd_byte_addr (c3_p0_cmd_byte_addr ),
.c3_p0_cmd_empty (c3_p0_cmd_empty ),
.c3_p0_cmd_full (c3_p0_cmd_full ),
.c3_p0_wr_clk (c3_p0_wr_clk ),
.c3_p0_wr_en (c3_p0_wr_en ),
.c3_p0_wr_mask (c3_p0_wr_mask ),
.c3_p0_wr_data (c3_p0_wr_data ),
.c3_p0_wr_full (c3_p0_wr_full ),
.c3_p0_wr_empty (c3_p0_wr_empty ),
.c3_p0_wr_count (c3_p0_wr_count ),
.c3_p0_wr_underrun (c3_p0_wr_underrun ),
.c3_p0_wr_error (c3_p0_wr_error ),
.c3_p0_rd_clk (c3_p0_rd_clk ),
.c3_p0_rd_en (c3_p0_rd_en ),
.c3_p0_rd_data (c3_p0_rd_data ),
.c3_p0_rd_full (c3_p0_rd_full ),
.c3_p0_rd_empty (c3_p0_rd_empty ),
.c3_p0_rd_count (c3_p0_rd_count ),
.c3_p0_rd_overflow (c3_p0_rd_overflow ),
.c3_p0_rd_error (c3_p0_rd_error ),
.c3_p1_cmd_clk (c3_p1_cmd_clk ),
.c3_p1_cmd_en (c3_p1_cmd_en ),
.c3_p1_cmd_instr (c3_p1_cmd_instr ),
.c3_p1_cmd_bl (c3_p1_cmd_bl ),
.c3_p1_cmd_byte_addr (c3_p1_cmd_byte_addr ),
.c3_p1_cmd_empty (c3_p1_cmd_empty ),
.c3_p1_cmd_full (c3_p1_cmd_full ),
.c3_p1_wr_clk (c3_p1_wr_clk ),
.c3_p1_wr_en (c3_p1_wr_en ),
.c3_p1_wr_mask (c3_p1_wr_mask ),
.c3_p1_wr_data (c3_p1_wr_data ),
.c3_p1_wr_full (c3_p1_wr_full ),
.c3_p1_wr_empty (c3_p1_wr_empty ),
.c3_p1_wr_count (c3_p1_wr_count ),
.c3_p1_wr_underrun (c3_p1_wr_underrun ),
.c3_p1_wr_error (c3_p1_wr_error ),
.c3_p1_rd_clk (c3_p1_rd_clk ),
.c3_p1_rd_en (c3_p1_rd_en ),
.c3_p1_rd_data (c3_p1_rd_data ),
.c3_p1_rd_full (c3_p1_rd_full ),
.c3_p1_rd_empty (c3_p1_rd_empty ),
.c3_p1_rd_count (c3_p1_rd_count ),
.c3_p1_rd_overflow (c3_p1_rd_overflow ),
.c3_p1_rd_error (c3_p1_rd_error )
);
endmodule
tb_ddr3_top模块：
`timescale 1ps / 1ps
// *********************************************************************************
// Project Name : OSXXXX
// Author : zhangningning
// Email : [email protected]
// Website :
// Module Name : tb_ddr3_top.v
// Create Time : 2020-02-21 23:21:37
// Editor : sublime text3, tab size (4)
// CopyRight(c) : All Rights Reserved
//
// *********************************************************************************
// Modification History:
// Date By Version Change Description
// -----------------------------------------------------------------------
// XXXX zhangningning 1.0 Original
//
// *********************************************************************************
module tb_ddr3_top;
parameter C3_MEMCLK_PERIOD = 3200 ;
wire [12:0] mcb3_dram_a ;
wire [02:0] mcb3_dram_ba ;
wire mcb3_dram_ck ;
wire mcb3_dram_ck_n ;
wire [15:0] mcb3_dram_dq ;
wire mcb3_dram_dqs ;
wire mcb3_dram_dqs_n ;
wire mcb3_dram_dm ;
wire mcb3_dram_ras_n ;
wire mcb3_dram_cas_n ;
wire mcb3_dram_we_n ;
wire mcb3_dram_cke ;
wire mcb3_dram_odt ;
wire mcb3_dram_reset_n ;
wire mcb3_dram_udqs ; // for X16 parts
wire mcb3_dram_udqs_n ; // for X16 parts
wire mcb3_dram_udm ; // for X16 parts
wire mcb3_rzq ;
wire mcb3_zio ;
reg c3_sys_clk ;
reg c3_sys_rst_i ;
initial c3_sys_clk = 1'b0;
always #(C3_MEMCLK_PERIOD/2) c3_sys_clk = ~c3_sys_clk;
initial begin
c3_sys_rst_i <= 1'b1;
#(100*C3_MEMCLK_PERIOD);
c3_sys_rst_i <= 1'b0;
end
PULLDOWN zio_pulldown3 (.O(mcb3_zio) );
PULLDOWN rzq_pulldown3 (.O(mcb3_rzq) );
ddr3_top ddr3_top_inst(
// DDR3 Interfaces
.mcb3_dram_dq (mcb3_dram_dq ),
.mcb3_dram_a (mcb3_dram_a ),
.mcb3_dram_ba (mcb3_dram_ba ),
.mcb3_dram_ras_n (mcb3_dram_ras_n ),
.mcb3_dram_cas_n (mcb3_dram_cas_n ),
.mcb3_dram_we_n (mcb3_dram_we_n ),
.mcb3_dram_odt (mcb3_dram_odt ),
.mcb3_dram_reset_n (mcb3_dram_reset_n ),
.mcb3_dram_cke (mcb3_dram_cke ),
.mcb3_dram_dm (mcb3_dram_dm ),
.mcb3_dram_udqs (mcb3_dram_udqs ),
.mcb3_dram_udqs_n (mcb3_dram_udqs_n ),
.mcb3_rzq (mcb3_rzq ),
.mcb3_zio (mcb3_zio ),
.mcb3_dram_udm (mcb3_dram_udm ),
.c3_sys_clk (c3_sys_clk ),
.c3_sys_rst_i (c3_sys_rst_i ),
.mcb3_dram_dqs (mcb3_dram_dqs ),
.mcb3_dram_dqs_n (mcb3_dram_dqs_n ),
.mcb3_dram_ck (mcb3_dram_ck ),
.mcb3_dram_ck_n (mcb3_dram_ck_n )
);
ddr3_model_c3 u_mem_c3(
.ck (mcb3_dram_ck ),
.ck_n (mcb3_dram_ck_n ),
.cke (mcb3_dram_cke ),
.cs_n (1'b0 ),
.ras_n (mcb3_dram_ras_n ),
.cas_n (mcb3_dram_cas_n ),
.we_n (mcb3_dram_we_n ),
.dm_tdqs ({mcb3_dram_udm,mcb3_dram_dm}),
.ba (mcb3_dram_ba ),
.addr (mcb3_dram_a ),
.dq (mcb3_dram_dq ),
.dqs ({mcb3_dram_udqs,mcb3_dram_dqs}),
.dqs_n ({mcb3_dram_udqs_n,mcb3_dram_dqs_n}),
.tdqs_n ( ),
.odt (mcb3_dram_odt ),
.rst_n (mcb3_dram_reset_n )
);
endmodule
仿真模型文件：
/****************************************************************************************
*
* File Name: ddr3.v
* Version: 1.61
* Model: BUS Functional
*
* Dependencies: ddr3_model_parameters_c3.vh
*
* Description: Micron SDRAM DDR3 (Double Data Rate 3)
*
* Limitation: - doesn't check for average refresh timings
* - positive ck and ck_n edges are used to form internal clock
* - positive dqs and dqs_n edges are used to latch data
* - test mode is not modeled
* - Duty Cycle Corrector is not modeled
* - Temperature Compensated Self Refresh is not modeled
* - DLL off mode is not modeled.
*
* Note: - Set simulator resolution to "ps" accuracy
* - Set DEBUG = 0 to disable $display messages
*
* Disclaimer This software code and all associated documentation, comments or other
* of Warranty: information (collectively "Software") is provided "AS IS" without
* warranty of any kind. MICRON TECHNOLOGY, INC. ("MTI") EXPRESSLY
* DISCLAIMS ALL WARRANTIES EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
* TO, NONINFRINGEMENT OF THIRD PARTY RIGHTS, AND ANY IMPLIED WARRANTIES
* OF MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE. MTI DOES NOT
* WARRANT THAT THE SOFTWARE WILL MEET YOUR REQUIREMENTS, OR THAT THE
* OPERATION OF THE SOFTWARE WILL BE UNINTERRUPTED OR ERROR-FREE.
* FURTHERMORE, MTI DOES NOT MAKE ANY REPRESENTATIONS REGARDING THE USE OR
* THE RESULTS OF THE USE OF THE SOFTWARE IN TERMS OF ITS CORRECTNESS,
* ACCURACY, RELIABILITY, OR OTHERWISE. THE ENTIRE RISK ARISING OUT OF USE
* OR PERFORMANCE OF THE SOFTWARE REMAINS WITH YOU. IN NO EVENT SHALL MTI,
* ITS AFFILIATED COMPANIES OR THEIR SUPPLIERS BE LIABLE FOR ANY DIRECT,
* INDIRECT, CONSEQUENTIAL, INCIDENTAL, OR SPECIAL DAMAGES (INCLUDING,
* WITHOUT LIMITATION, DAMAGES FOR LOSS OF PROFITS, BUSINESS INTERRUPTION,
* OR LOSS OF INFORMATION) ARISING OUT OF YOUR USE OF OR INABILITY TO USE
* THE SOFTWARE, EVEN IF MTI HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGES. Because some jurisdictions prohibit the exclusion or
* limitation of liability for consequential or incidental damages, the
* above limitation may not apply to you.
*
* Copyright 2003 Micron Technology, Inc. All rights reserved.
*
* Rev Author Date Changes
* ---------------------------------------------------------------------------------------
* 0.41 JMK 05/12/06 Removed auto-precharge to power down error check.
* 0.42 JMK 08/25/06 Created internal clock using ck and ck_n.
* TDQS can only be enabled in EMR for x8 configurations.
* CAS latency is checked vs frequency when DLL locks.
* Improved checking of DQS during writes.
* Added true BL4 operation.
* 0.43 JMK 08/14/06 Added checking for setting reserved bits in Mode Registers.
* Added ODTS Readout.
* Replaced tZQCL with tZQinit and tZQoper
* Fixed tWRPDEN and tWRAPDEN during BC4MRS and BL4MRS.
* Added tRFC checking for Refresh to Power-Down Re-Entry.
* Added tXPDLL checking for Power-Down Exit to Refresh to Power-Down Entry
* Added Clock Frequency Change during Precharge Power-Down.
* Added -125x speed grades.
* Fixed tRCD checking during Write.
* 1.00 JMK 05/11/07 Initial release
* 1.10 JMK 06/26/07 Fixed ODTH8 check during BLOTF
* Removed temp sensor readout from MPR
* Updated initialization sequence
* Updated timing parameters
* 1.20 JMK 09/05/07 Updated clock frequency change
* Added ddr3_dimm module
* 1.30 JMK 01/23/08 Updated timing parameters
* 1.40 JMK 12/02/08 Added support for DDR3-1866 and DDR3-2133
* renamed ddr3_dimm.v to ddr3_module.v and added SODIMM support.
* Added multi-chip package model support in ddr3_mcp.v
* 1.50 JMK 05/04/08 Added 1866 and 2133 speed grades.
* 1.60 MYY 07/10/09 Merging of 1.50 version and pre-1.0 version changes
* 1.61 SPH 12/10/09 Only check tIH for cmd_addr if CS# LOW
*****************************************************************************************/
// DO NOT CHANGE THE TIMESCALE
// MAKE SURE YOUR SIMULATOR USES "PS" RESOLUTION
`timescale 1ps / 1ps
// model flags
// `define MODEL_PASR
module ddr3_model_c3(
rst_n,
ck,
ck_n,
cke,
cs_n,
ras_n,
cas_n,
we_n,
dm_tdqs,
ba,
addr,
dq,
dqs,
dqs_n,
tdqs_n,
odt
);
`include "ddr3_model_parameters_c3.vh"
parameter check_strict_mrbits = 1;
parameter check_strict_timing = 1;
parameter feature_pasr = 1;
parameter feature_truebl4 = 0;
// text macros
`define DQ_PER_DQS DQ_BITS/DQS_BITS
`define BANKS (1<<BA_BITS)
`define MAX_BITS (BA_BITS+ROW_BITS+COL_BITS-BL_BITS)
`define MAX_SIZE (1<<(BA_BITS+ROW_BITS+COL_BITS-BL_BITS))
`define MEM_SIZE (1<<MEM_BITS)
`define MAX_PIPE 4*CL_MAX
// Declare Ports
input rst_n;
input ck;
input ck_n;
input cke;
input cs_n;
input ras_n;
input cas_n;
input we_n;
inout [DM_BITS-1:0] dm_tdqs;
input [BA_BITS-1:0] ba;
input [ADDR_BITS-1:0] addr;
inout [DQ_BITS-1:0] dq;
inout [DQS_BITS-1:0] dqs;
inout [DQS_BITS-1:0] dqs_n;
output [DQS_BITS-1:0] tdqs_n;
input odt;
// clock jitter
real tck_avg;
time tck_sample [TDLLK-1:0];
time tch_sample [TDLLK-1:0];
time tcl_sample [TDLLK-1:0];
time tck_i;
time tch_i;
time tcl_i;
real tch_avg;
real tcl_avg;
time tm_ck_pos;
time tm_ck_neg;
real tjit_per_rtime;
integer tjit_cc_time;
real terr_nper_rtime;
//DDR3 clock jitter variables
real tjit_ch_rtime;
real duty_cycle;
// clock skew
real out_delay;
integer dqsck [DQS_BITS-1:0];
integer dqsck_min;
integer dqsck_max;
integer dqsq_min;
integer dqsq_max;
integer seed;
// Mode Registers
reg [ADDR_BITS-1:0] mode_reg [`BANKS-1:0];
reg burst_order;
reg [BL_BITS:0] burst_length;
reg blotf;
reg truebl4;
integer cas_latency;
reg dll_reset;
reg dll_locked;
integer write_recovery;
reg low_power;
reg dll_en;
reg [2:0] odt_rtt_nom;
reg [1:0] odt_rtt_wr;
reg odt_en;
reg dyn_odt_en;
reg [1:0] al;
integer additive_latency;
reg write_levelization;
reg duty_cycle_corrector;
reg tdqs_en;
reg out_en;
reg [2:0] pasr;
integer cas_write_latency;
reg asr; // auto self refresh
reg srt; // self refresh temperature range
reg [1:0] mpr_select;
reg mpr_en;
reg odts_readout;
integer read_latency;
integer write_latency;
// cmd encoding
parameter // {cs, ras, cas, we}
LOAD_MODE = 4'b0000,
REFRESH = 4'b0001,
PRECHARGE = 4'b0010,
ACTIVATE = 4'b0011,
WRITE = 4'b0100,
READ = 4'b0101,
ZQ = 4'b0110,
NOP = 4'b0111,
// DESEL = 4'b1xxx,
PWR_DOWN = 4'b1000,
SELF_REF = 4'b1001
;
reg [8*9-1:0] cmd_string [9:0];
initial begin
cmd_string[LOAD_MODE] = "Load Mode";
cmd_string[REFRESH ] = "Refresh ";
cmd_string[PRECHARGE] = "Precharge";
cmd_string[ACTIVATE ] = "Activate ";
cmd_string[WRITE ] = "Write ";
cmd_string[READ ] = "Read ";
cmd_string[ZQ ] = "ZQ ";
cmd_string[NOP ] = "No Op ";
cmd_string[PWR_DOWN ] = "Pwr Down ";
cmd_string[SELF_REF ] = "Self Ref ";
end
// command state
reg [`BANKS-1:0] active_bank;
reg [`BANKS-1:0] auto_precharge_bank;
reg [`BANKS-1:0] write_precharge_bank;
reg [`BANKS-1:0] read_precharge_bank;
reg [ROW_BITS-1:0] active_row [`BANKS-1:0];
reg in_power_down;
reg in_self_refresh;
reg [3:0] init_mode_reg;
reg init_dll_reset;
reg init_done;
integer init_step;
reg zq_set;
reg er_trfc_max;
reg odt_state;
reg odt_state_dly;
reg dyn_odt_state;
reg dyn_odt_state_dly;
reg prev_odt;
wire [7:0] calibration_pattern = 8'b10101010; // value returned during mpr pre-defined pattern readout
wire [7:0] temp_sensor = 8'h01; // value returned during mpr temp sensor readout
reg [1:0] mr_chk;
reg rd_bc;
integer banki;
// cmd timers/counters
integer ref_cntr;
integer odt_cntr;
integer ck_cntr;
integer ck_txpr;
integer ck_load_mode;
integer ck_refresh;
integer ck_precharge;
integer ck_activate;
integer ck_write;
integer ck_read;
integer ck_zqinit;
integer ck_zqoper;
integer ck_zqcs;
integer ck_power_down;
integer ck_slow_exit_pd;
integer ck_self_refresh;
integer ck_freq_change;
integer ck_odt;
integer ck_odth8;
integer ck_dll_reset;
integer ck_cke_cmd;
integer ck_bank_write [`BANKS-1:0];
integer ck_bank_read [`BANKS-1:0];
integer ck_group_activate [1:0];
integer ck_group_write [1:0];
integer ck_group_read [1:0];
time tm_txpr;
time tm_load_mode;
time tm_refresh;
time tm_precharge;
time tm_activate;
time tm_write_end;
time tm_power_down;
time tm_slow_exit_pd;
time tm_self_refresh;
time tm_freq_change;
time tm_cke_cmd;
time tm_ttsinit;
time tm_bank_precharge [`BANKS-1:0];
time tm_bank_activate [`BANKS-1:0];
time tm_bank_write_end [`BANKS-1:0];
time tm_bank_read_end [`BANKS-1:0];
time tm_group_activate [1:0];
time tm_group_write_end [1:0];
// pipelines
reg [`MAX_PIPE:0] al_pipeline;
reg [`MAX_PIPE:0] wr_pipeline;
reg [`MAX_PIPE:0] rd_pipeline;
reg [`MAX_PIPE:0] odt_pipeline;
reg [`MAX_PIPE:0] dyn_odt_pipeline;
reg [BL_BITS:0] bl_pipeline [`MAX_PIPE:0];
reg [BA_BITS-1:0] ba_pipeline [`MAX_PIPE:0];
reg [ROW_BITS-1:0] row_pipeline [`MAX_PIPE:0];
reg [COL_BITS-1:0] col_pipeline [`MAX_PIPE:0];
reg prev_cke;
// data state
reg [BL_MAX*DQ_BITS-1:0] memory_data;
reg [BL_MAX*DQ_BITS-1:0] bit_mask;
reg [BL_BITS-1:0] burst_position;
reg [BL_BITS:0] burst_cntr;
reg [DQ_BITS-1:0] dq_temp;
reg [31:0] check_write_postamble;
reg [31:0] check_write_preamble;
reg [31:0] check_write_dqs_high;
reg [31:0] check_write_dqs_low;
reg [15:0] check_dm_tdipw;
reg [63:0] check_dq_tdipw;
// data timers/counters
time tm_rst_n;
time tm_cke;
time tm_odt;
time tm_tdqss;
time tm_dm [15:0];
time tm_dqs [15:0];
time tm_dqs_pos [31:0];
time tm_dqss_pos [31:0];
time tm_dqs_neg [31:0];
time tm_dq [63:0];
time tm_cmd_addr [22:0];
reg [8*7-1:0] cmd_addr_string [22:0];
initial begin
cmd_addr_string[ 0] = "CS_N ";
cmd_addr_string[ 1] = "RAS_N ";
cmd_addr_string[ 2] = "CAS_N ";
cmd_addr_string[ 3] = "WE_N ";
cmd_addr_string[ 4] = "BA 0 ";
cmd_addr_string[ 5] = "BA 1 ";
cmd_addr_string[ 6] = "BA 2 ";
cmd_addr_string[ 7] = "ADDR 0";
cmd_addr_string[ 8] = "ADDR 1";
cmd_addr_string[ 9] = "ADDR 2";
cmd_addr_string[10] = "ADDR 3";
cmd_addr_string[11] = "ADDR 4";
cmd_addr_string[12] = "ADDR 5";
cmd_addr_string[13] = "ADDR 6";
cmd_addr_string[14] = "ADDR 7";
cmd_addr_string[15] = "ADDR 8";
cmd_addr_string[16] = "ADDR 9";
cmd_addr_string[17] = "ADDR 10";
cmd_addr_string[18] = "ADDR 11";
cmd_addr_string[19] = "ADDR 12";
cmd_addr_string[20] = "ADDR 13";
cmd_addr_string[21] = "ADDR 14";
cmd_addr_string[22] = "ADDR 15";
end
reg [8*5-1:0] dqs_string [1:0];
initial begin
dqs_string[0] = "DQS ";
dqs_string[1] = "DQS_N";
end
// Memory Storage
`ifdef MAX_MEM
parameter RFF_BITS = DQ_BITS*BL_MAX;
// %z format uses 8 bytes for every 32 bits or less.
parameter RFF_CHUNK = 8 * (RFF_BITS/32 + (RFF_BITS%32 ? 1 : 0));
reg [1024:1] tmp_model_dir;
integer memfd[`BANKS-1:0];
initial
begin : file_io_open
integer bank;
if (!$value$plusargs("model_data+%s", tmp_model_dir))
begin
tmp_model_dir = "/tmp";
$display(
"%m: at time %t WARNING: no +model_data option specified, using /tmp.",
$time
);
end
for (bank = 0; bank < `BANKS; bank = bank + 1)
memfd[bank] = open_bank_file(bank);
end
`else
reg [BL_MAX*DQ_BITS-1:0] memory [0:`MEM_SIZE-1];
reg [`MAX_BITS-1:0] address [0:`MEM_SIZE-1];
reg [MEM_BITS:0] memory_index;
reg [MEM_BITS:0] memory_used = 0;
`endif
// receive
reg rst_n_in;
reg ck_in;
reg ck_n_in;
reg cke_in;
reg cs_n_in;
reg ras_n_in;
reg cas_n_in;
reg we_n_in;
reg [15:0] dm_in;
reg [2:0] ba_in;
reg [15:0] addr_in;
reg [63:0] dq_in;
reg [31:0] dqs_in;
reg odt_in;
reg [15:0] dm_in_pos;
reg [15:0] dm_in_neg;
reg [63:0] dq_in_pos;
reg [63:0] dq_in_neg;
reg dq_in_valid;
reg dqs_in_valid;
integer wdqs_cntr;
integer wdq_cntr;
integer wdqs_pos_cntr [31:0];
reg b2b_write;
reg [BL_BITS:0] wr_burst_length;
reg [31:0] prev_dqs_in;
reg diff_ck;
always @(rst_n ) rst_n_in <= #BUS_DELAY rst_n;
always @(ck ) ck_in <= #BUS_DELAY ck;
always @(ck_n ) ck_n_in <= #BUS_DELAY ck_n;
always @(cke ) cke_in <= #BUS_DELAY cke;
always @(cs_n ) cs_n_in <= #BUS_DELAY cs_n;
always @(ras_n ) ras_n_in <= #BUS_DELAY ras_n;
always @(cas_n ) cas_n_in <= #BUS_DELAY cas_n;
always @(we_n ) we_n_in <= #BUS_DELAY we_n;
always @(dm_tdqs) dm_in <= #BUS_DELAY dm_tdqs;
always @(ba ) ba_in <= #BUS_DELAY ba;
always @(addr ) addr_in <= #BUS_DELAY addr;
always @(dq ) dq_in <= #BUS_DELAY dq;
always @(dqs or dqs_n) dqs_in <= #BUS_DELAY (dqs_n<<16) | dqs;
always @(odt ) odt_in <= #BUS_DELAY odt;
// create internal clock
always @(posedge ck_in) diff_ck <= ck_in;
always @(posedge ck_n_in) diff_ck <= ~ck_n_in;
wire [15:0] dqs_even = dqs_in[15:0];
wire [15:0] dqs_odd = dqs_in[31:16];
wire [3:0] cmd_n_in = !cs_n_in ? {ras_n_in, cas_n_in, we_n_in} : NOP; //deselect = nop
// transmit
reg dqs_out_en;
reg [DQS_BITS-1:0] dqs_out_en_dly;
reg dqs_out;
reg [DQS_BITS-1:0] dqs_out_dly;
reg dq_out_en;
reg [DQ_BITS-1:0] dq_out_en_dly;
reg [DQ_BITS-1:0] dq_out;
reg [DQ_BITS-1:0] dq_out_dly;
integer rdqsen_cntr;
integer rdqs_cntr;
integer rdqen_cntr;
integer rdq_cntr;
bufif1 buf_dqs [DQS_BITS-1:0] (dqs, dqs_out_dly, dqs_out_en_dly & {DQS_BITS{out_en}});
bufif1 buf_dqs_n [DQS_BITS-1:0] (dqs_n, ~dqs_out_dly, dqs_out_en_dly & {DQS_BITS{out_en}});
bufif1 buf_dq [DQ_BITS-1:0] (dq, dq_out_dly, dq_out_en_dly & {DQ_BITS {out_en}});
assign tdqs_n = {DQS_BITS{1'bz}};
initial begin
if (BL_MAX < 2)
$display("%m ERROR: BL_MAX parameter must be >= 2. \nBL_MAX = %d", BL_MAX);
if ((1<<BO_BITS) > BL_MAX)
$display("%m ERROR: 2^BO_BITS cannot be greater than BL_MAX parameter.");
$timeformat (-12, 1, " ps", 1);
seed = RANDOM_SEED;
ck_cntr = 0;
end
function integer get_rtt_wr;
input [1:0] rtt;
begin
get_rtt_wr = RZQ/{rtt[0], rtt[1], 1'b0};
end
endfunction
function integer get_rtt_nom;
input [2:0] rtt;
begin
case (rtt)
1: get_rtt_nom = RZQ/4;
2: get_rtt_nom = RZQ/2;
3: get_rtt_nom = RZQ/6;
4: get_rtt_nom = RZQ/12;
5: get_rtt_nom = RZQ/8;
default : get_rtt_nom = 0;
endcase
end
endfunction
// calculate the absolute value of a real number
function real abs_value;
input arg;
real arg;
begin
if (arg < 0.0)
abs_value = -1.0 * arg;
else
abs_value = arg;
end
endfunction
function integer ceil;
input number;
real number;
// LMR 4.1.7
// When either operand of a relational expression is a real operand then the other operand shall be converted
// to an equivalent real value, and the expression shall be interpreted as a comparison between two real values.
if (number > $rtoi(number))
ceil = $rtoi(number) + 1;
else
ceil = number;
endfunction
function integer floor;
input number;
real number;
// LMR 4.1.7
// When either operand of a relational expression is a real operand then the other operand shall be converted
// to an equivalent real value, and the expression shall be interpreted as a comparison between two real values.
if (number < $rtoi(number))
floor = $rtoi(number) - 1;
else
floor = number;
endfunction
`ifdef MAX_MEM
function integer open_bank_file( input integer bank );
integer fd;
reg [2048:1] filename;
begin
$sformat( filename, "%0s/%m.%0d", tmp_model_dir, bank );
fd = $fopen(filename, "w+");
if (fd == 0)
begin
$display("%m: at time %0t ERROR: failed to open %0s.", $time, filename);
$finish;
end
else
begin
if (DEBUG) $display("%m: at time %0t INFO: opening %0s.", $time, filename);
open_bank_file = fd;
end
end
endfunction
function [RFF_BITS:1] read_from_file(
input integer fd,
input integer index
);
integer code;
integer offset;
reg [1024:1] msg;
reg [RFF_BITS:1] read_value;
begin
offset = index * RFF_CHUNK;
code = $fseek( fd, offset, 0 );
// $fseek returns 0 on success, -1 on failure
if (code != 0)
begin
$display("%m: at time %t ERROR: fseek to %d failed", $time, offset);
$finish;
end
code = $fscanf(fd, "%z", read_value);
// $fscanf returns number of items read
if (code != 1)
begin
if ($ferror(fd,msg) != 0)
begin
$display("%m: at time %t ERROR: fscanf failed at %d", $time, index);
$display(msg);
$finish;
end
else
read_value = 'hx;
end
/* when reading from unwritten portions of the file, 0 will be returned.
* Use 0 in bit 1 as indicator that invalid data has been read.
* A true 0 is encoded as Z.
*/
if (read_value[1] === 1'bz)
// true 0 encoded as Z, data is valid
read_value[1] = 1'b0;
else if (read_value[1] === 1'b0)
// read from file section that has not been written
read_value = 'hx;
read_from_file = read_value;
end
endfunction
task write_to_file(
input integer fd,
input integer index,
input [RFF_BITS:1] data
);
integer code;
integer offset;
begin
offset = index * RFF_CHUNK;
code = $fseek( fd, offset, 0 );
if (code != 0)
begin
$display("%m: at time %t ERROR: fseek to %d failed", $time, offset);
$finish;
end
// encode a valid data
if (data[1] === 1'bz)
data[1] = 1'bx;
else if (data[1] === 1'b0)
data[1] = 1'bz;
$fwrite( fd, "%z", data );
end
endtask
`else
function get_index;
input [`MAX_BITS-1:0] addr;
begin : index
get_index = 0;
for (memory_index=0; memory_index<memory_used; memory_index=memory_index+1) begin
if (address[memory_index] == addr) begin
get_index = 1;
disable index;
end
end
end
endfunction
`endif
task memory_write;
input [BA_BITS-1:0] bank;
input [ROW_BITS-1:0] row;
input [COL_BITS-1:0] col;
input [BL_MAX*DQ_BITS-1:0] data;
reg [`MAX_BITS-1:0] addr;
begin
`ifdef MAX_MEM
addr = {row, col}/BL_MAX;
write_to_file( memfd[bank], addr, data );
`else
// chop off the lowest address bits
addr = {bank, row, col}/BL_MAX;
if (get_index(addr)) begin
address[memory_index] = addr;
memory[memory_index] = data;
end else if (memory_used == `MEM_SIZE) begin
$display ("%m: at time %t ERROR: Memory overflow. Write to Address %h with Data %h will be lost.\nYou must increase the MEM_BITS parameter or define MAX_MEM.", $time, addr, data);
if (STOP_ON_ERROR) $stop(0);
end else begin
address[memory_used] = addr;
memory[memory_used] = data;
memory_used = memory_used + 1;
end
`endif
end
endtask
task memory_read;
input [BA_BITS-1:0] bank;
input [ROW_BITS-1:0] row;
input [COL_BITS-1:0] col;
output [BL_MAX*DQ_BITS-1:0] data;
reg [`MAX_BITS-1:0] addr;
begin
`ifdef MAX_MEM
addr = {row, col}/BL_MAX;
data = read_from_file( memfd[bank], addr );
`else
// chop off the lowest address bits
addr = {bank, row, col}/BL_MAX;
if (get_index(addr)) begin
data = memory[memory_index];
end else begin
data = {BL_MAX*DQ_BITS{1'bx}};
end
`endif
end
endtask
task set_latency;
begin
if (al == 0) begin
additive_latency = 0;
end else begin
additive_latency = cas_latency - al;
end
read_latency = cas_latency + additive_latency;
write_latency = cas_write_latency + additive_latency;
end
endtask
// this task will erase the contents of 0 or more banks
task erase_banks;
input [`BANKS-1:0] banks; //one select bit per bank
reg [BA_BITS-1:0] ba;
reg [`MAX_BITS-1:0] i;
integer bank;
begin
`ifdef MAX_MEM
for (bank = 0; bank < `BANKS; bank = bank + 1)
if (banks[bank] === 1'b1) begin
$fclose(memfd[bank]);
memfd[bank] = open_bank_file(bank);
end
`else
memory_index = 0;
i = 0;
// remove the selected banks
for (memory_index=0; memory_index<memory_used; memory_index=memory_index+1) begin
ba = (address[memory_index]>>(ROW_BITS+COL_BITS-BL_BITS));
if (!banks[ba]) begin //bank is selected to keep
address[i] = address[memory_index];
memory[i] = memory[memory_index];
i = i + 1;
end
end
// clean up the unused banks
for (memory_index=i; memory_index<memory_used; memory_index=memory_index+1) begin
address[memory_index] = 'bx;
memory[memory_index] = {8*DQ_BITS{1'bx}};
end
memory_used = i;
`endif
end
endtask
// Before this task runs, the model must be in a valid state for precharge power down and out of reset.
// After this task runs, NOP commands must be issued until TZQINIT has been met
task initialize;
input [ADDR_BITS-1:0] mode_reg0;
input [ADDR_BITS-1:0] mode_reg1;
input [ADDR_BITS-1:0] mode_reg2;
input [ADDR_BITS-1:0] mode_reg3;
begin
if (DEBUG) $display ("%m: at time %t INFO: Performing Initialization Sequence", $time);
cmd_task(1, NOP, 'bx, 'bx);
cmd_task(1, ZQ, 'bx, 'h400); //ZQCL
cmd_task(1, LOAD_MODE, 3, mode_reg3);
cmd_task(1, LOAD_MODE, 2, mode_reg2);
cmd_task(1, LOAD_MODE, 1, mode_reg1);
cmd_task(1, LOAD_MODE, 0, mode_reg0 | 'h100); // DLL Reset
cmd_task(0, NOP, 'bx, 'bx);
end
endtask
task reset_task;
integer i;
begin
// disable inputs
dq_in_valid = 0;
dqs_in_valid <= 0;
wdqs_cntr = 0;
wdq_cntr = 0;
for (i=0; i<31; i=i+1) begin
wdqs_pos_cntr[i] <= 0;
end
b2b_write <= 0;
// disable outputs
out_en = 0;
dq_out_en = 0;
rdq_cntr = 0;
dqs_out_en = 0;
rdqs_cntr = 0;
// disable ODT
odt_en = 0;
dyn_odt_en = 0;
odt_state = 0;
dyn_odt_state = 0;
// reset bank state
active_bank = 0;
auto_precharge_bank = 0;
read_precharge_bank = 0;
write_precharge_bank = 0;
// require initialization sequence
init_done = 0;
mpr_en = 0;
init_step = 0;
init_mode_reg = 0;
init_dll_reset = 0;
zq_set = 0;
// reset DLL
dll_en = 0;
dll_reset = 0;
dll_locked = 0;
// exit power down and self refresh
prev_cke = 1'bx;
in_power_down = 0;
in_self_refresh = 0;
// clear pipelines
al_pipeline = 0;
wr_pipeline = 0;
rd_pipeline = 0;
odt_pipeline = 0;
dyn_odt_pipeline = 0;
end
endtask
parameter SAME_BANK = 2'd0; // same bank, same group
parameter DIFF_BANK = 2'd1; // different bank, same group
parameter DIFF_GROUP = 2'd2; // different bank, different group
task chk_err;
input [1:0] relationship;
input [BA_BITS-1:0] bank;
input [3:0] fromcmd;
input [3:0] cmd;
reg err;
begin
// $display ("truebl4 = %d, relationship = %d, fromcmd = %h, cmd = %h", truebl4, relationship, fromcmd, cmd);
casex ({truebl4, relationship, fromcmd, cmd})
// load mode
{1'bx, DIFF_BANK , LOAD_MODE, LOAD_MODE} : begin if (ck_cntr - ck_load_mode < TMRD) $display ("%m: at time %t ERROR: tMRD violation during %s", $time, cmd_string[cmd]); end
{1'bx, DIFF_BANK , LOAD_MODE, READ } : begin if (($time - tm_load_mode < TMOD) || (ck_cntr - ck_load_mode < TMOD_TCK)) $display ("%m: at time %t ERROR: tMOD violation during %s", $time, cmd_string[cmd]); end
{1'bx, DIFF_BANK , LOAD_MODE, REFRESH } ,
{1'bx, DIFF_BANK , LOAD_MODE, PRECHARGE} ,
{1'bx, DIFF_BANK , LOAD_MODE, ACTIVATE } ,
{1'bx, DIFF_BANK , LOAD_MODE, ZQ } ,
{1'bx, DIFF_BANK , LOAD_MODE, PWR_DOWN } ,
{1'bx, DIFF_BANK , LOAD_MODE, SELF_REF } : begin if (($time - tm_load_mode < TMOD) || (ck_cntr - ck_load_mode < TMOD_TCK)) $display ("%m: at time %t ERROR: tMOD violation during %s", $time, cmd_string[cmd]); end
// refresh
{1'bx, DIFF_BANK , REFRESH , LOAD_MODE} ,
{1'bx, DIFF_BANK , REFRESH , REFRESH } ,
{1'bx, DIFF_BANK , REFRESH , PRECHARGE} ,
{1'bx, DIFF_BANK , REFRESH , ACTIVATE } ,
{1'bx, DIFF_BANK , REFRESH , ZQ } ,
{1'bx, DIFF_BANK , REFRESH , SELF_REF } : begin if ($time - tm_refresh < TRFC_MIN) $display ("%m: at time %t ERROR: tRFC violation during %s", $time, cmd_string[cmd]); end
{1'bx, DIFF_BANK , REFRESH , PWR_DOWN } : begin if (ck_cntr - ck_refresh < TREFPDEN) $display ("%m: at time %t ERROR: tREFPDEN violation during %s", $time, cmd_string[cmd]); end
// precharge
{1'bx, SAME_BANK , PRECHARGE, ACTIVATE } : begin if ($time - tm_bank_precharge[bank] < TRP) $display ("%m: at time %t ERROR: tRP violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'bx, DIFF_BANK , PRECHARGE, LOAD_MODE} ,
{1'bx, DIFF_BANK , PRECHARGE, REFRESH } ,
{1'bx, DIFF_BANK , PRECHARGE, ZQ } ,
{1'bx, DIFF_BANK , PRECHARGE, SELF_REF } : begin if ($time - tm_precharge < TRP) $display ("%m: at time %t ERROR: tRP violation during %s", $time, cmd_string[cmd]); end
{1'bx, DIFF_BANK , PRECHARGE, PWR_DOWN } : ; //tPREPDEN = 1 tCK, can be concurrent with auto precharge
// activate
{1'bx, SAME_BANK , ACTIVATE , PRECHARGE} : begin if ($time - tm_bank_activate[bank] > TRAS_MAX) $display ("%m: at time %t ERROR: tRAS maximum violation during %s to bank %d", $time, cmd_string[cmd], bank);
if ($time - tm_bank_activate[bank] < TRAS_MIN) $display ("%m: at time %t ERROR: tRAS minimum violation during %s to bank %d", $time, cmd_string[cmd], bank);end
{1'bx, SAME_BANK , ACTIVATE , ACTIVATE } : begin if ($time - tm_bank_activate[bank] < TRC) $display ("%m: at time %t ERROR: tRC violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'bx, SAME_BANK , ACTIVATE , WRITE } ,
{1'bx, SAME_BANK , ACTIVATE , READ } : ; // tRCD is checked outside this task
{1'b0, DIFF_BANK , ACTIVATE , ACTIVATE } : begin if (($time - tm_activate < TRRD) || (ck_cntr - ck_activate < TRRD_TCK)) $display ("%m: at time %t ERROR: tRRD violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b1, DIFF_BANK , ACTIVATE , ACTIVATE } : begin if (($time - tm_group_activate[bank[1]] < TRRD) || (ck_cntr - ck_group_activate[bank[1]] < TRRD_TCK)) $display ("%m: at time %t ERROR: tRRD violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b1, DIFF_GROUP, ACTIVATE , ACTIVATE } : begin if (($time - tm_activate < TRRD_DG) || (ck_cntr - ck_activate < TRRD_DG_TCK)) $display ("%m: at time %t ERROR: tRRD_DG violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'bx, DIFF_BANK , ACTIVATE , REFRESH } : begin if ($time - tm_activate < TRC) $display ("%m: at time %t ERROR: tRC violation during %s", $time, cmd_string[cmd]); end
{1'bx, DIFF_BANK , ACTIVATE , PWR_DOWN } : begin if (ck_cntr - ck_activate < TACTPDEN) $display ("%m: at time %t ERROR: tACTPDEN violation during %s", $time, cmd_string[cmd]); end
// write
{1'bx, SAME_BANK , WRITE , PRECHARGE} : begin if (($time - tm_bank_write_end[bank] < TWR) || (ck_cntr - ck_bank_write[bank] <= write_latency + burst_length/2)) $display ("%m: at time %t ERROR: tWR violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b0, DIFF_BANK , WRITE , WRITE } : begin if (ck_cntr - ck_write < TCCD) $display ("%m: at time %t ERROR: tCCD violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b1, DIFF_BANK , WRITE , WRITE } : begin if (ck_cntr - ck_group_write[bank[1]] < TCCD) $display ("%m: at time %t ERROR: tCCD violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b0, DIFF_BANK , WRITE , READ } : begin if (ck_cntr - ck_write < write_latency + burst_length/2 + TWTR_TCK - additive_latency) $display ("%m: at time %t ERROR: tWTR violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b1, DIFF_BANK , WRITE , READ } : begin if (ck_cntr - ck_group_write[bank[1]] < write_latency + burst_length/2 + TWTR_TCK - additive_latency) $display ("%m: at time %t ERROR: tWTR violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b1, DIFF_GROUP, WRITE , WRITE } : begin if (ck_cntr - ck_write < TCCD_DG) $display ("%m: at time %t ERROR: tCCD_DG violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b1, DIFF_GROUP, WRITE , READ } : begin if (ck_cntr - ck_write < write_latency + burst_length/2 + TWTR_DG_TCK - additive_latency) $display ("%m: at time %t ERROR: tWTR_DG violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'bx, DIFF_BANK , WRITE , PWR_DOWN } : begin if (($time - tm_write_end < TWR) || (ck_cntr - ck_write < write_latency + burst_length/2)) $display ("%m: at time %t ERROR: tWRPDEN violation during %s", $time, cmd_string[cmd]); end
// read
{1'bx, SAME_BANK , READ , PRECHARGE} : begin if (($time - tm_bank_read_end[bank] < TRTP) || (ck_cntr - ck_bank_read[bank] < additive_latency + TRTP_TCK)) $display ("%m: at time %t ERROR: tRTP violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b0, DIFF_BANK , READ , WRITE } : ; // tRTW is checked outside this task
{1'b1, DIFF_BANK , READ , WRITE } : ; // tRTW is checked outside this task
{1'b0, DIFF_BANK , READ , READ } : begin if (ck_cntr - ck_read < TCCD) $display ("%m: at time %t ERROR: tCCD violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b1, DIFF_BANK , READ , READ } : begin if (ck_cntr - ck_group_read[bank[1]] < TCCD) $display ("%m: at time %t ERROR: tCCD violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'b1, DIFF_GROUP, READ , WRITE } : ; // tRTW is checked outside this task
{1'b1, DIFF_GROUP, READ , READ } : begin if (ck_cntr - ck_read < TCCD_DG) $display ("%m: at time %t ERROR: tCCD_DG violation during %s to bank %d", $time, cmd_string[cmd], bank); end
{1'bx, DIFF_BANK , READ , PWR_DOWN } : begin if (ck_cntr - ck_read < read_latency + 5) $display ("%m: at time %t ERROR: tRDPDEN violation during %s", $time, cmd_string[cmd]); end
// zq
{1'bx, DIFF_BANK , ZQ , LOAD_MODE} : ; // 1 tCK
{1'bx, DIFF_BANK , ZQ , REFRESH } ,
{1'bx, DIFF_BANK , ZQ , PRECHARGE} ,
{1'bx, DIFF_BANK , ZQ , ACTIVATE } ,
{1'bx, DIFF_BANK , ZQ , ZQ } ,
{1'bx, DIFF_BANK , ZQ , PWR_DOWN } ,
{1'bx, DIFF_BANK , ZQ , SELF_REF } : begin if (ck_cntr - ck_zqinit < TZQINIT) $display ("%m: at time %t ERROR: tZQinit violation during %s", $time, cmd_string[cmd]);
if (ck_cntr - ck_zqoper < TZQOPER) $display ("%m: at time %t ERROR: tZQoper violation during %s", $time, cmd_string[cmd]);
if (ck_cntr - ck_zqcs < TZQCS) $display ("%m: at time %t ERROR: tZQCS violation during %s", $time, cmd_string[cmd]); end
// power down
{1'bx, DIFF_BANK , PWR_DOWN , LOAD_MODE} ,
{1'bx, DIFF_BANK , PWR_DOWN , REFRESH } ,
{1'bx, DIFF_BANK , PWR_DOWN , PRECHARGE} ,
{1'bx, DIFF_BANK , PWR_DOWN , ACTIVATE } ,
{1'bx, DIFF_BANK , PWR_DOWN , WRITE } ,
{1'bx, DIFF_BANK , PWR_DOWN , ZQ } : begin if (($time - tm_power_down < TXP) || (ck_cntr - ck_power_down < TXP_TCK)) $display ("%m: at time %t ERROR: tXP violation during %s", $time, cmd_string[cmd]); end
{1'bx, DIFF_BANK , PWR_DOWN , READ } : begin if (($time - tm_power_down < TXP) || (ck_cntr - ck_power_down < TXP_TCK)) $display ("%m: at time %t ERROR: tXP violation during %s", $time, cmd_string[cmd]);
else if (($time - tm_slow_exit_pd < TXPDLL) || (ck_cntr - ck_slow_exit_pd < TXPDLL_TCK)) $display ("%m: at time %t ERROR: tXPDLL violation during %s", $time, cmd_string[cmd]); end
{1'bx, DIFF_BANK , PWR_DOWN , PWR_DOWN } ,
{1'bx, DIFF_BANK , PWR_DOWN , SELF_REF } : begin if (($time - tm_power_down < TXP) || (ck_cntr - ck_power_down < TXP_TCK)) $display ("%m: at time %t ERROR: tXP violation during %s", $time, cmd_string[cmd]);
if ((tm_power_down > tm_refresh) && ($time - tm_refresh < TRFC_MIN)) $display ("%m: at time %t ERROR: tRFC violation during %s", $time, cmd_string[cmd]);
if ((tm_refresh > tm_power_down) && (($time - tm_power_down < TXPDLL) || (ck_cntr - ck_power_down < TXPDLL_TCK))) $display ("%m: at time %t ERROR: tXPDLL violation during %s", $time, cmd_string[cmd]);
if (($time - tm_cke_cmd < TCKE) || (ck_cntr - ck_cke_cmd < TCKE_TCK)) $display ("%m: at time %t ERROR: tCKE violation on CKE", $time); end
// self refresh
{1'bx, DIFF_BANK , SELF_REF , LOAD_MODE} ,
{1'bx, DIFF_BANK , SELF_REF , REFRESH } ,
{1'bx, DIFF_BANK , SELF_REF , PRECHARGE} ,
{1'bx, DIFF_BANK , SELF_REF , ACTIVATE } ,
{1'bx, DIFF_BANK , SELF_REF , WRITE } ,
{1'bx, DIFF_BANK , SELF_REF , ZQ } : begin if (($time - tm_self_refresh < TXS) || (ck_cntr - ck_self_refresh < TXS_TCK)) $display ("%m: at time %t ERROR: tXS violation during %s", $time, cmd_string[cmd]); end
{1'bx, DIFF_BANK , SELF_REF , READ } : begin if (ck_cntr - ck_self_refresh < TXSDLL) $display ("%m: at time %t ERROR: tXSDLL violation during %s", $time, cmd_string[cmd]); end
{1'bx, DIFF_BANK , SELF_REF , PWR_DOWN } ,
{1'bx, DIFF_BANK , SELF_REF , SELF_REF } : begin if (($time - tm_self_refresh < TXS) || (ck_cntr - ck_self_refresh < TXS_TCK)) $display ("%m: at time %t ERROR: tXS violation during %s", $time, cmd_string[cmd]);
if (($time - tm_cke_cmd < TCKE) || (ck_cntr - ck_cke_cmd < TCKE_TCK)) $display ("%m: at time %t ERROR: tCKE violation on CKE", $time); end
endcase
end
endtask
task cmd_task;
input cke;
input [2:0] cmd;
input [BA_BITS-1:0] bank;
input [ADDR_BITS-1:0] addr;
reg [`BANKS:0] i;
integer j;
reg [`BANKS:0] tfaw_cntr;
reg [COL_BITS-1:0] col;
reg group;
begin
// tRFC max check
if (!er_trfc_max && !in_self_refresh) begin
if ($time - tm_refresh > TRFC_MAX && check_strict_timing) begin
$display ("%m: at time %t ERROR: tRFC maximum violation during %s", $time, cmd_string[cmd]);
er_trfc_max = 1;
end
end
if (cke) begin
if ((cmd < NOP) && (cmd != PRECHARGE)) begin
if (($time - tm_txpr < TXPR) || (ck_cntr - ck_txpr < TXPR_TCK))
$display ("%m: at time %t ERROR: tXPR violation during %s", $time, cmd_string[cmd]);
for (j=0; j<=SELF_REF; j=j+1) begin
chk_err(SAME_BANK , bank, j, cmd);
chk_err(DIFF_BANK , bank, j, cmd);
chk_err(DIFF_GROUP, bank, j, cmd);
end
end
case (cmd)
LOAD_MODE : begin
if (|odt_pipeline)
$display ("%m: at time %t ERROR: ODTL violation during %s", $time, cmd_string[cmd]);
if (odt_state)
$display ("%m: at time %t ERROR: ODT must be off prior to %s", $time, cmd_string[cmd]);
if (|active_bank) begin
$display ("%m: at time %t ERROR: %s Failure. All banks must be Precharged.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d", $time, cmd_string[cmd], bank);
if (bank>>2) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved bank bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
case (bank)
0 : begin
// Burst Length
if (addr[1:0] == 2'b00) begin
burst_length = 8;
blotf = 0;
truebl4 = 0;
if (DEBUG) $display ("%m: at time %t INFO: %s %d Burst Length = %d", $time, cmd_string[cmd], bank, burst_length);
end else if (addr[1:0] == 2'b01) begin
burst_length = 8;
blotf = 1;
truebl4 = 0;
if (DEBUG) $display ("%m: at time %t INFO: %s %d Burst Length = Select via A12", $time, cmd_string[cmd], bank);
end else if (addr[1:0] == 2'b10) begin
burst_length = 4;
blotf = 0;
truebl4 = 0;
if (DEBUG) $display ("%m: at time %t INFO: %s %d Burst Length = Fixed %d (chop)", $time, cmd_string[cmd], bank, burst_length);
end else if (feature_truebl4 && (addr[1:0] == 2'b11)) begin
burst_length = 4;
blotf = 0;
truebl4 = 1;
if (DEBUG) $display ("%m: at time %t INFO: %s %d Burst Length = True %d", $time, cmd_string[cmd], bank, burst_length);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Burst Length = %d", $time, cmd_string[cmd], bank, addr[1:0]);
end
// Burst Order
burst_order = addr[3];
if (!burst_order) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Burst Order = Sequential", $time, cmd_string[cmd], bank);
end else if (burst_order) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Burst Order = Interleaved", $time, cmd_string[cmd], bank);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Burst Order = %d", $time, cmd_string[cmd], bank, burst_order);
end
// CAS Latency
cas_latency = {addr[2],addr[6:4]} + 4;
set_latency;
if ((cas_latency >= CL_MIN) && (cas_latency <= CL_MAX)) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d CAS Latency = %d", $time, cmd_string[cmd], bank, cas_latency);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal CAS Latency = %d", $time, cmd_string[cmd], bank, cas_latency);
end
// Reserved
if (addr[7] !== 0 && check_strict_mrbits) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved address bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
// DLL Reset
dll_reset = addr[8];
if (!dll_reset) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d DLL Reset = Normal", $time, cmd_string[cmd], bank);
end else if (dll_reset) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d DLL Reset = Reset DLL", $time, cmd_string[cmd], bank);
dll_locked = 0;
init_dll_reset = 1;
ck_dll_reset <= ck_cntr;
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal DLL Reset = %d", $time, cmd_string[cmd], bank, dll_reset);
end
// Write Recovery
if (addr[11:9] == 0) begin
write_recovery = 16;
end else if (addr[11:9] < 4) begin
write_recovery = addr[11:9] + 4;
end else begin
write_recovery = 2*addr[11:9];
end
if ((write_recovery >= WR_MIN) && (write_recovery <= WR_MAX)) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Write Recovery = %d", $time, cmd_string[cmd], bank, write_recovery);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Write Recovery = %d", $time, cmd_string[cmd], bank, write_recovery);
end
// Power Down Mode
low_power = !addr[12];
if (!low_power) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Power Down Mode = DLL on", $time, cmd_string[cmd], bank);
end else if (low_power) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Power Down Mode = DLL off", $time, cmd_string[cmd], bank);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Power Down Mode = %d", $time, cmd_string[cmd], bank, low_power);
end
// Reserved
if (ADDR_BITS>13 && addr[13] !== 0 && check_strict_mrbits) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved address bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
end
1 : begin
// DLL Enable
dll_en = !addr[0];
if (!dll_en) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d DLL Enable = Disabled", $time, cmd_string[cmd], bank);
if (check_strict_mrbits) $display ("%m: at time %t WARNING: %s %d DLL off mode is not modeled", $time, cmd_string[cmd], bank);
end else if (dll_en) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d DLL Enable = Enabled", $time, cmd_string[cmd], bank);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal DLL Enable = %d", $time, cmd_string[cmd], bank, dll_en);
end
// Output Drive Strength
if ({addr[5], addr[1]} == 2'b00) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Output Drive Strength = %d Ohm", $time, cmd_string[cmd], bank, RZQ/6);
end else if ({addr[5], addr[1]} == 2'b01) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Output Drive Strength = %d Ohm", $time, cmd_string[cmd], bank, RZQ/7);
end else if ({addr[5], addr[1]} == 2'b11) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Output Drive Strength = %d Ohm", $time, cmd_string[cmd], bank, RZQ/5);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Output Drive Strength = %d", $time, cmd_string[cmd], bank, {addr[5], addr[1]});
end
// ODT Rtt (Rtt_NOM)
odt_rtt_nom = {addr[9], addr[6], addr[2]};
if (odt_rtt_nom == 3'b000) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d ODT Rtt = Disabled", $time, cmd_string[cmd], bank);
odt_en = 0;
end else if ((odt_rtt_nom < 4) || ((!addr[7] || (addr[7] && addr[12])) && (odt_rtt_nom < 6))) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d ODT Rtt = %d Ohm", $time, cmd_string[cmd], bank, get_rtt_nom(odt_rtt_nom));
odt_en = 1;
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal ODT Rtt = %d", $time, cmd_string[cmd], bank, odt_rtt_nom);
odt_en = 0;
end
// Report the additive latency value
al = addr[4:3];
set_latency;
if (al == 0) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Additive Latency = %d", $time, cmd_string[cmd], bank, al);
end else if ((al >= AL_MIN) && (al <= AL_MAX)) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Additive Latency = CL - %d", $time, cmd_string[cmd], bank, al);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Additive Latency = %d", $time, cmd_string[cmd], bank, al);
end
// Write Levelization
write_levelization = addr[7];
if (!write_levelization) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Write Levelization = Disabled", $time, cmd_string[cmd], bank);
end else if (write_levelization) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Write Levelization = Enabled", $time, cmd_string[cmd], bank);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Write Levelization = %d", $time, cmd_string[cmd], bank, write_levelization);
end
// Reserved
if (addr[8] !== 0 && check_strict_mrbits) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved address bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
// Reserved
if (addr[10] !== 0 && check_strict_mrbits) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved address bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
// TDQS Enable
tdqs_en = addr[11];
if (!tdqs_en) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d TDQS Enable = Disabled", $time, cmd_string[cmd], bank);
end else if (tdqs_en) begin
if (8 == DQ_BITS) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d TDQS Enable = Enabled", $time, cmd_string[cmd], bank);
end
else begin
$display ("%m: at time %t WARNING: %s %d Illegal TDQS Enable. TDQS only exists on a x8 part", $time, cmd_string[cmd], bank);
tdqs_en = 0;
end
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal TDQS Enable = %d", $time, cmd_string[cmd], bank, tdqs_en);
end
// Output Enable
out_en = !addr[12];
if (!out_en) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Qoff = Disabled", $time, cmd_string[cmd], bank);
end else if (out_en) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Qoff = Enabled", $time, cmd_string[cmd], bank);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Qoff = %d", $time, cmd_string[cmd], bank, out_en);
end
// Reserved
if (ADDR_BITS>13 && addr[13] !== 0 && check_strict_mrbits) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved address bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
end
2 : begin
if (feature_pasr) begin
// Partial Array Self Refresh
pasr = addr[2:0];
case (pasr)
3'b000 : if (DEBUG) $display ("%m: at time %t INFO: %s %d Partial Array Self Refresh = Bank 0-7", $time, cmd_string[cmd], bank);
3'b001 : if (DEBUG) $display ("%m: at time %t INFO: %s %d Partial Array Self Refresh = Bank 0-3", $time, cmd_string[cmd], bank);
3'b010 : if (DEBUG) $display ("%m: at time %t INFO: %s %d Partial Array Self Refresh = Bank 0-1", $time, cmd_string[cmd], bank);
3'b011 : if (DEBUG) $display ("%m: at time %t INFO: %s %d Partial Array Self Refresh = Bank 0", $time, cmd_string[cmd], bank);
3'b100 : if (DEBUG) $display ("%m: at time %t INFO: %s %d Partial Array Self Refresh = Bank 2-7", $time, cmd_string[cmd], bank);
3'b101 : if (DEBUG) $display ("%m: at time %t INFO: %s %d Partial Array Self Refresh = Bank 4-7", $time, cmd_string[cmd], bank);
3'b110 : if (DEBUG) $display ("%m: at time %t INFO: %s %d Partial Array Self Refresh = Bank 6-7", $time, cmd_string[cmd], bank);
3'b111 : if (DEBUG) $display ("%m: at time %t INFO: %s %d Partial Array Self Refresh = Bank 7", $time, cmd_string[cmd], bank);
default : $display ("%m: at time %t ERROR: %s %d Illegal Partial Array Self Refresh = %d", $time, cmd_string[cmd], bank, pasr);
endcase
end
else
if (addr[2:0] !== 0 && check_strict_mrbits) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved address bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
// CAS Write Latency
cas_write_latency = addr[5:3]+5;
set_latency;
if ((cas_write_latency >= CWL_MIN) && (cas_write_latency <= CWL_MAX)) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d CAS Write Latency = %d", $time, cmd_string[cmd], bank, cas_write_latency);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal CAS Write Latency = %d", $time, cmd_string[cmd], bank, cas_write_latency);
end
// Auto Self Refresh Method
asr = addr[6];
if (!asr) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Auto Self Refresh = Disabled", $time, cmd_string[cmd], bank);
end else if (asr) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Auto Self Refresh = Enabled", $time, cmd_string[cmd], bank);
if (check_strict_mrbits) $display ("%m: at time %t WARNING: %s %d Auto Self Refresh is not modeled", $time, cmd_string[cmd], bank);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Auto Self Refresh = %d", $time, cmd_string[cmd], bank, asr);
end
// Self Refresh Temperature
srt = addr[7];
if (!srt) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Self Refresh Temperature = Normal", $time, cmd_string[cmd], bank);
end else if (srt) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Self Refresh Temperature = Extended", $time, cmd_string[cmd], bank);
if (check_strict_mrbits) $display ("%m: at time %t WARNING: %s %d Self Refresh Temperature is not modeled", $time, cmd_string[cmd], bank);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Self Refresh Temperature = %d", $time, cmd_string[cmd], bank, srt);
end
if (asr && srt)
$display ("%m: at time %t ERROR: %s %d SRT must be set to 0 when ASR is enabled.", $time, cmd_string[cmd], bank);
// Reserved
if (addr[8] !== 0 && check_strict_mrbits) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved address bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
// Dynamic ODT (Rtt_WR)
odt_rtt_wr = addr[10:9];
if (odt_rtt_wr == 2'b00) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Dynamic ODT = Disabled", $time, cmd_string[cmd], bank);
dyn_odt_en = 0;
end else if ((odt_rtt_wr > 0) && (odt_rtt_wr < 3)) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d Dynamic ODT Rtt = %d Ohm", $time, cmd_string[cmd], bank, get_rtt_wr(odt_rtt_wr));
dyn_odt_en = 1;
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal Dynamic ODT = %d", $time, cmd_string[cmd], bank, odt_rtt_wr);
dyn_odt_en = 0;
end
// Reserved
if (ADDR_BITS>13 && addr[13:11] !== 0 && check_strict_mrbits) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved address bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
end
3 : begin
mpr_select = addr[1:0];
// MultiPurpose Register Select
if (mpr_select == 2'b00) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d MultiPurpose Register Select = Pre-defined pattern", $time, cmd_string[cmd], bank);
end else begin
if (check_strict_mrbits) $display ("%m: at time %t ERROR: %s %d Illegal MultiPurpose Register Select = %d", $time, cmd_string[cmd], bank, mpr_select);
end
// MultiPurpose Register Enable
mpr_en = addr[2];
if (!mpr_en) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d MultiPurpose Register Enable = Disabled", $time, cmd_string[cmd], bank);
end else if (mpr_en) begin
if (DEBUG) $display ("%m: at time %t INFO: %s %d MultiPurpose Register Enable = Enabled", $time, cmd_string[cmd], bank);
end else begin
$display ("%m: at time %t ERROR: %s %d Illegal MultiPurpose Register Enable = %d", $time, cmd_string[cmd], bank, mpr_en);
end
// Reserved
if (ADDR_BITS>13 && addr[13:3] !== 0 && check_strict_mrbits) begin
$display ("%m: at time %t ERROR: %s %d Illegal value. Reserved address bits must be programmed to zero", $time, cmd_string[cmd], bank);
end
end
endcase
if (dyn_odt_en && write_levelization)
$display ("%m: at time %t ERROR: Dynamic ODT is not available during Write Leveling mode.", $time);
init_mode_reg[bank] = 1;
mode_reg[bank] = addr;
tm_load_mode <= $time;
ck_load_mode <= ck_cntr;
end
end
REFRESH : begin
if (mpr_en) begin
$display ("%m: at time %t ERROR: %s Failure. Multipurpose Register must be disabled.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else if (|active_bank) begin
$display ("%m: at time %t ERROR: %s Failure. All banks must be Precharged.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (DEBUG) $display ("%m: at time %t INFO: %s", $time, cmd_string[cmd]);
er_trfc_max = 0;
ref_cntr = ref_cntr + 1;
tm_refresh <= $time;
ck_refresh <= ck_cntr;
end
end
PRECHARGE : begin
if (addr[AP]) begin
if (DEBUG) $display ("%m: at time %t INFO: %s All", $time, cmd_string[cmd]);
end
// PRECHARGE command will be treated as a NOP if there is no open row in that bank (idle state),
// or if the previously open row is already in the process of precharging
if (|active_bank) begin
if (($time - tm_txpr < TXPR) || (ck_cntr - ck_txpr < TXPR_TCK))
$display ("%m: at time %t ERROR: tXPR violation during %s", $time, cmd_string[cmd]);
if (mpr_en) begin
$display ("%m: at time %t ERROR: %s Failure. Multipurpose Register must be disabled.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else begin
for (i=0; i<`BANKS; i=i+1) begin
if (active_bank[i]) begin
if (addr[AP] || (i == bank)) begin
for (j=0; j<=SELF_REF; j=j+1) begin
chk_err(SAME_BANK, i, j, cmd);
chk_err(DIFF_BANK, i, j, cmd);
end
if (auto_precharge_bank[i]) begin
$display ("%m: at time %t ERROR: %s Failure. Auto Precharge is scheduled to bank %d.", $time, cmd_string[cmd], i);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (DEBUG) $display ("%m: at time %t INFO: %s bank %d", $time, cmd_string[cmd], i);
active_bank[i] = 1'b0;
tm_bank_precharge[i] <= $time;
tm_precharge <= $time;
ck_precharge <= ck_cntr;
end
end
end
end
end
end
end
ACTIVATE : begin
tfaw_cntr = 0;
for (i=0; i<`BANKS; i=i+1) begin
if ($time - tm_bank_activate[i] < TFAW) begin
tfaw_cntr = tfaw_cntr + 1;
end
end
if (tfaw_cntr > 3) begin
$display ("%m: at time %t ERROR: tFAW violation during %s to bank %d", $time, cmd_string[cmd], bank);
end
if (mpr_en) begin
$display ("%m: at time %t ERROR: %s Failure. Multipurpose Register must be disabled.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else if (!init_done) begin
$display ("%m: at time %t ERROR: %s Failure. Initialization sequence is not complete.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else if (active_bank[bank]) begin
$display ("%m: at time %t ERROR: %s Failure. Bank %d must be Precharged.", $time, cmd_string[cmd], bank);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (addr >= 1<<ROW_BITS) begin
$display ("%m: at time %t WARNING: row = %h does not exist. Maximum row = %h", $time, addr, (1<<ROW_BITS)-1);
end
if (DEBUG) $display ("%m: at time %t INFO: %s bank %d row %h", $time, cmd_string[cmd], bank, addr);
active_bank[bank] = 1'b1;
active_row[bank] = addr;
tm_group_activate[bank[1]] <= $time;
tm_activate <= $time;
tm_bank_activate[bank] <= $time;
ck_group_activate[bank[1]] <= ck_cntr;
ck_activate <= ck_cntr;
end
end
WRITE : begin
if ((!rd_bc && blotf) || (burst_length == 4)) begin // BL=4
if (truebl4) begin
if (ck_cntr - ck_group_read[bank[1]] < read_latency + TCCD/2 + 2 - write_latency)
$display ("%m: at time %t ERROR: tRTW violation during %s to bank %d", $time, cmd_string[cmd], bank);
if (ck_cntr - ck_read < read_latency + TCCD_DG/2 + 2 - write_latency)
$display ("%m: at time %t ERROR: tRTW_DG violation during %s to bank %d", $time, cmd_string[cmd], bank);
end else begin
if (ck_cntr - ck_read < read_latency + TCCD/2 + 2 - write_latency)
$display ("%m: at time %t ERROR: tRTW violation during %s to bank %d", $time, cmd_string[cmd], bank);
end
end else begin // BL=8
if (ck_cntr - ck_read < read_latency + TCCD + 2 - write_latency)
$display ("%m: at time %t ERROR: tRTW violation during %s to bank %d", $time, cmd_string[cmd], bank);
end
if (mpr_en) begin
$display ("%m: at time %t ERROR: %s Failure. Multipurpose Register must be disabled.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else if (!init_done) begin
$display ("%m: at time %t ERROR: %s Failure. Initialization sequence is not complete.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else if (!active_bank[bank]) begin
if (check_strict_timing) $display ("%m: at time %t ERROR: %s Failure. Bank %d must be Activated.", $time, cmd_string[cmd], bank);
if (STOP_ON_ERROR) $stop(0);
end else if (auto_precharge_bank[bank]) begin
$display ("%m: at time %t ERROR: %s Failure. Auto Precharge is scheduled to bank %d.", $time, cmd_string[cmd], bank);
if (STOP_ON_ERROR) $stop(0);
end else if (ck_cntr - ck_write < burst_length/2) begin
$display ("%m: at time %t ERROR: %s Failure. Illegal burst interruption.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (addr[AP]) begin
auto_precharge_bank[bank] = 1'b1;
write_precharge_bank[bank] = 1'b1;
end
col = {addr[BC-1:AP+1], addr[AP-1:0]}; // assume BC > AP
if (col >= 1<<COL_BITS) begin
$display ("%m: at time %t WARNING: col = %h does not exist. Maximum col = %h", $time, col, (1<<COL_BITS)-1);
end
if ((!addr[BC] && blotf) || (burst_length == 4)) begin // BL=4
col = col & -4;
end else begin // BL=8
col = col & -8;
end
if (DEBUG) $display ("%m: at time %t INFO: %s bank %d col %h, auto precharge %d", $time, cmd_string[cmd], bank, col, addr[AP]);
wr_pipeline[2*write_latency + 1] = 1;
ba_pipeline[2*write_latency + 1] = bank;
row_pipeline[2*write_latency + 1] = active_row[bank];
col_pipeline[2*write_latency + 1] = col;
if ((!addr[BC] && blotf) || (burst_length == 4)) begin // BL=4
bl_pipeline[2*write_latency + 1] = 4;
if (mpr_en && col%4) begin
$display ("%m: at time %t WARNING: col[1:0] must be set to 2'b00 during a BL4 Multipurpose Register read", $time);
end
end else begin // BL=8
bl_pipeline[2*write_latency + 1] = 8;
if (odt_in) begin
ck_odth8 <= ck_cntr;
end
end
for (j=0; j<(burst_length + 4); j=j+1) begin
dyn_odt_pipeline[2*(write_latency - 2) + j] = 1'b1; // ODTLcnw = WL - 2, ODTLcwn = BL/2 + 2
end
ck_bank_write[bank] <= ck_cntr;
ck_group_write[bank[1]] <= ck_cntr;
ck_write <= ck_cntr;
end
end
READ : begin
if (!dll_locked)
$display ("%m: at time %t WARNING: tDLLK violation during %s.", $time, cmd_string[cmd]);
if (mpr_en && (addr[1:0] != 2'b00)) begin
$display ("%m: at time %t ERROR: %s Failure. addr[1:0] must be zero during Multipurpose Register Read.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else if (!init_done) begin
$display ("%m: at time %t ERROR: %s Failure. Initialization sequence is not complete.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else if (!active_bank[bank] && !mpr_en) begin
if (check_strict_timing) $display ("%m: at time %t ERROR: %s Failure. Bank %d must be Activated.", $time, cmd_string[cmd], bank);
if (STOP_ON_ERROR) $stop(0);
end else if (auto_precharge_bank[bank]) begin
$display ("%m: at time %t ERROR: %s Failure. Auto Precharge is scheduled to bank %d.", $time, cmd_string[cmd], bank);
if (STOP_ON_ERROR) $stop(0);
end else if (ck_cntr - ck_read < burst_length/2) begin
$display ("%m: at time %t ERROR: %s Failure. Illegal burst interruption.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (addr[AP] && !mpr_en) begin
auto_precharge_bank[bank] = 1'b1;
read_precharge_bank[bank] = 1'b1;
end
col = {addr[BC-1:AP+1], addr[AP-1:0]}; // assume BC > AP
if (col >= 1<<COL_BITS) begin
$display ("%m: at time %t WARNING: col = %h does not exist. Maximum col = %h", $time, col, (1<<COL_BITS)-1);
end
if (DEBUG) $display ("%m: at time %t INFO: %s bank %d col %h, auto precharge %d", $time, cmd_string[cmd], bank, col, addr[AP]);
rd_pipeline[2*read_latency - 1] = 1;
ba_pipeline[2*read_latency - 1] = bank;
row_pipeline[2*read_latency - 1] = active_row[bank];
col_pipeline[2*read_latency - 1] = col;
if ((!addr[BC] && blotf) || (burst_length == 4)) begin // BL=4
bl_pipeline[2*read_latency - 1] = 4;
if (mpr_en && col%4) begin
$display ("%m: at time %t WARNING: col[1:0] must be set to 2'b00 during a BL4 Multipurpose Register read", $time);
end
end else begin // BL=8
bl_pipeline[2*read_latency - 1] = 8;
if (mpr_en && col%8) begin
$display ("%m: at time %t WARNING: col[2:0] must be set to 3'b000 during a BL8 Multipurpose Register read", $time);
end
end
rd_bc = addr[BC];
ck_bank_read[bank] <= ck_cntr;
ck_group_read[bank[1]] <= ck_cntr;
ck_read <= ck_cntr;
end
end
ZQ : begin
if (mpr_en) begin
$display ("%m: at time %t ERROR: %s Failure. Multipurpose Register must be disabled.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else if (|active_bank) begin
$display ("%m: at time %t ERROR: %s Failure. All banks must be Precharged.", $time, cmd_string[cmd]);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (DEBUG) $display ("%m: at time %t INFO: %s long = %d", $time, cmd_string[cmd], addr[AP]);
if (addr[AP]) begin
zq_set = 1;
if (init_done) begin
ck_zqoper <= ck_cntr;
end else begin
ck_zqinit <= ck_cntr;
end
end else begin
ck_zqcs <= ck_cntr;
end
end
end
NOP: begin
if (in_power_down) begin
if (($time - tm_freq_change < TCKSRX) || (ck_cntr - ck_freq_change < TCKSRX_TCK))
$display ("%m: at time %t ERROR: tCKSRX violation during Power Down Exit", $time);
if ($time - tm_cke_cmd > TPD_MAX)
$display ("%m: at time %t ERROR: tPD maximum violation during Power Down Exit", $time);
if (DEBUG) $display ("%m: at time %t INFO: Power Down Exit", $time);
in_power_down = 0;
if ((active_bank == 0) && low_power) begin // precharge power down with dll off
if (ck_cntr - ck_odt < write_latency - 1)
$display ("%m: at time %t WARNING: tANPD violation during Power Down Exit. Synchronous or asynchronous change in termination resistance is possible.", $time);
tm_slow_exit_pd <= $time;
ck_slow_exit_pd <= ck_cntr;
end
tm_power_down <= $time;
ck_power_down <= ck_cntr;
end
if (in_self_refresh) begin
if (($time - tm_freq_change < TCKSRX) || (ck_cntr - ck_freq_change < TCKSRX_TCK))
$display ("%m: at time %t ERROR: tCKSRX violation during Self Refresh Exit", $time);
if (ck_cntr - ck_cke_cmd < TCKESR_TCK)
$display ("%m: at time %t ERROR: tCKESR violation during Self Refresh Exit", $time);
if ($time - tm_cke < TISXR)
$display ("%m: at time %t ERROR: tISXR violation during Self Refresh Exit", $time);
if (DEBUG) $display ("%m: at time %t INFO: Self Refresh Exit", $time);
in_self_refresh = 0;
ck_dll_reset <= ck_cntr;
ck_self_refresh <= ck_cntr;
tm_self_refresh <= $time;
tm_refresh <= $time;
end
end
endcase
if ((prev_cke !== 1) && (cmd !== NOP)) begin
$display ("%m: at time %t ERROR: NOP or Deselect is required when CKE goes active.", $time);
end
if (!init_done) begin
case (init_step)
0 : begin
if ($time - tm_rst_n < 500000000 && check_strict_timing)
$display ("%m at time %t WARNING: 500 us is required after RST_N goes inactive before CKE goes active.", $time);
tm_txpr <= $time;
ck_txpr <= ck_cntr;
init_step = init_step + 1;
end
1 : if (dll_en) init_step = init_step + 1;
2 : begin
if (&init_mode_reg && init_dll_reset && zq_set) begin
if (DEBUG) $display ("%m: at time %t INFO: Initialization Sequence is complete", $time);
init_done = 1;
end
end
endcase
end
end else if (prev_cke) begin
if ((!init_done) && (init_step > 1)) begin
$display ("%m: at time %t ERROR: CKE must remain active until the initialization sequence is complete.", $time);
if (STOP_ON_ERROR) $stop(0);
end
case (cmd)
REFRESH : begin
if ($time - tm_txpr < TXPR)
$display ("%m: at time %t ERROR: tXPR violation during %s", $time, cmd_string[SELF_REF]);
for (j=0; j<=SELF_REF; j=j+1) begin
chk_err(DIFF_BANK, bank, j, SELF_REF);
end
if (mpr_en) begin
$display ("%m: at time %t ERROR: Self Refresh Failure. Multipurpose Register must be disabled.", $time);
if (STOP_ON_ERROR) $stop(0);
end else if (|active_bank) begin
$display ("%m: at time %t ERROR: Self Refresh Failure. All banks must be Precharged.", $time);
if (STOP_ON_ERROR) $stop(0);
end else if (odt_state) begin
$display ("%m: at time %t ERROR: Self Refresh Failure. ODT must be off prior to entering Self Refresh", $time);
if (STOP_ON_ERROR) $stop(0);
end else if (!init_done) begin
$display ("%m: at time %t ERROR: Self Refresh Failure. Initialization sequence is not complete.", $time);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (DEBUG) $display ("%m: at time %t INFO: Self Refresh Enter", $time);
if (feature_pasr)
// Partial Array Self Refresh
case (pasr)
3'b000 : ;//keep Bank 0-7
3'b001 : begin if (DEBUG) $display("%m: at time %t INFO: Banks 4-7 will be lost due to Partial Array Self Refresh", $time); erase_banks(8'hF0); end
3'b010 : begin if (DEBUG) $display("%m: at time %t INFO: Banks 2-7 will be lost due to Partial Array Self Refresh", $time); erase_banks(8'hFC); end
3'b011 : begin if (DEBUG) $display("%m: at time %t INFO: Banks 1-7 will be lost due to Partial Array Self Refresh", $time); erase_banks(8'hFE); end
3'b100 : begin if (DEBUG) $display("%m: at time %t INFO: Banks 0-1 will be lost due to Partial Array Self Refresh", $time); erase_banks(8'h03); end
3'b101 : begin if (DEBUG) $display("%m: at time %t INFO: Banks 0-3 will be lost due to Partial Array Self Refresh", $time); erase_banks(8'h0F); end
3'b110 : begin if (DEBUG) $display("%m: at time %t INFO: Banks 0-5 will be lost due to Partial Array Self Refresh", $time); erase_banks(8'h3F); end
3'b111 : begin if (DEBUG) $display("%m: at time %t INFO: Banks 0-6 will be lost due to Partial Array Self Refresh", $time); erase_banks(8'h7F); end
endcase
in_self_refresh = 1;
dll_locked = 0;
end
end
NOP : begin
// entering precharge power down with dll off and tANPD has not been satisfied
if (low_power && (active_bank == 0) && |odt_pipeline)
$display ("%m: at time %t WARNING: tANPD violation during %s. Synchronous or asynchronous change in termination resistance is possible.", $time, cmd_string[PWR_DOWN]);
if ($time - tm_txpr < TXPR)
$display ("%m: at time %t ERROR: tXPR violation during %s", $time, cmd_string[PWR_DOWN]);
for (j=0; j<=SELF_REF; j=j+1) begin
chk_err(DIFF_BANK, bank, j, PWR_DOWN);
end
if (mpr_en) begin
$display ("%m: at time %t ERROR: Power Down Failure. Multipurpose Register must be disabled.", $time);
if (STOP_ON_ERROR) $stop(0);
end else if (!init_done) begin
$display ("%m: at time %t ERROR: Power Down Failure. Initialization sequence is not complete.", $time);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (DEBUG) begin
if (|active_bank) begin
$display ("%m: at time %t INFO: Active Power Down Enter", $time);
end else begin
$display ("%m: at time %t INFO: Precharge Power Down Enter", $time);
end
end
in_power_down = 1;
end
end
default : begin
$display ("%m: at time %t ERROR: NOP, Deselect, or Refresh is required when CKE goes inactive.", $time);
end
endcase
end else if (in_self_refresh || in_power_down) begin
if ((ck_cntr - ck_cke_cmd <= TCPDED) && (cmd !== NOP))
$display ("%m: at time %t ERROR: tCPDED violation during Power Down or Self Refresh Entry. NOP or Deselect is required.", $time);
end
prev_cke = cke;
end
endtask
task data_task;
reg [BA_BITS-1:0] bank;
reg [ROW_BITS-1:0] row;
reg [COL_BITS-1:0] col;
integer i;
integer j;
begin
if (diff_ck) begin
for (i=0; i<32; i=i+1) begin
if (dq_in_valid && dll_locked && ($time - tm_dqs_neg[i] < $rtoi(TDSS*tck_avg)))
$display ("%m: at time %t ERROR: tDSS violation on %s bit %d", $time, dqs_string[i/16], i%16);
if (check_write_dqs_high[i])
$display ("%m: at time %t ERROR: %s bit %d latching edge required during the preceding clock period.", $time, dqs_string[i/16], i%16);
end
check_write_dqs_high <= 0;
end else begin
for (i=0; i<32; i=i+1) begin
if (dll_locked && dq_in_valid) begin
tm_tdqss = abs_value(1.0*tm_ck_pos - tm_dqss_pos[i]);
if ((tm_tdqss < tck_avg/2.0) && (tm_tdqss > TDQSS*tck_avg))
$display ("%m: at time %t ERROR: tDQSS violation on %s bit %d", $time, dqs_string[i/16], i%16);
end
if (check_write_dqs_low[i])
$display ("%m: at time %t ERROR: %s bit %d latching edge required during the preceding clock period", $time, dqs_string[i/16], i%16);
end
check_write_preamble <= 0;
check_write_postamble <= 0;
check_write_dqs_low <= 0;
end
if (wr_pipeline[0] || rd_pipeline[0]) begin
bank = ba_pipeline[0];
row = row_pipeline[0];
col = col_pipeline[0];
burst_cntr = 0;
memory_read(bank, row, col, memory_data);
end
// burst counter
if (burst_cntr < burst_length) begin
burst_position = col ^ burst_cntr;
if (!burst_order) begin
burst_position[BO_BITS-1:0] = col + burst_cntr;
end
burst_cntr = burst_cntr + 1;
end
// write dqs counter
if (wr_pipeline[WDQS_PRE + 1]) begin
wdqs_cntr = WDQS_PRE + bl_pipeline[WDQS_PRE + 1] + WDQS_PST - 1;
end
// write dqs
if ((wr_pipeline[2]) && (wdq_cntr == 0)) begin //write preamble
check_write_preamble <= ({DQS_BITS{1'b1}}<<16) | {DQS_BITS{1'b1}};
end
if (wdqs_cntr > 1) begin // write data
if ((wdqs_cntr - WDQS_PST)%2) begin
check_write_dqs_high <= ({DQS_BITS{1'b1}}<<16) | {DQS_BITS{1'b1}};
end else begin
check_write_dqs_low <= ({DQS_BITS{1'b1}}<<16) | {DQS_BITS{1'b1}};
end
end
if (wdqs_cntr == WDQS_PST) begin // write postamble
check_write_postamble <= ({DQS_BITS{1'b1}}<<16) | {DQS_BITS{1'b1}};
end
if (wdqs_cntr > 0) begin
wdqs_cntr = wdqs_cntr - 1;
end
// write dq
if (dq_in_valid) begin // write data
bit_mask = 0;
if (diff_ck) begin
for (i=0; i<DM_BITS; i=i+1) begin
bit_mask = bit_mask | ({`DQ_PER_DQS{~dm_in_neg[i]}}<<(burst_position*DQ_BITS + i*`DQ_PER_DQS));
end
memory_data = (dq_in_neg<<(burst_position*DQ_BITS) & bit_mask) | (memory_data & ~bit_mask);
end else begin
for (i=0; i<DM_BITS; i=i+1) begin
bit_mask = bit_mask | ({`DQ_PER_DQS{~dm_in_pos[i]}}<<(burst_position*DQ_BITS + i*`DQ_PER_DQS));
end
memory_data = (dq_in_pos<<(burst_position*DQ_BITS) & bit_mask) | (memory_data & ~bit_mask);
end
dq_temp = memory_data>>(burst_position*DQ_BITS);
if (DEBUG) $display ("%m: at time %t INFO: WRITE @ DQS= bank = %h row = %h col = %h data = %h",$time, bank, row, (-1*BL_MAX & col) + burst_position, dq_temp);
if (burst_cntr%BL_MIN == 0) begin
memory_write(bank, row, col, memory_data);
end
end
if (wr_pipeline[1]) begin
wdq_cntr = bl_pipeline[1];
end
if (wdq_cntr > 0) begin
wdq_cntr = wdq_cntr - 1;
dq_in_valid = 1'b1;
end else begin
dq_in_valid = 1'b0;
dqs_in_valid <= 1'b0;
for (i=0; i<31; i=i+1) begin
wdqs_pos_cntr[i] <= 0;
end
end
if (wr_pipeline[0]) begin
b2b_write <= 1'b0;
end
if (wr_pipeline[2]) begin
if (dqs_in_valid) begin
b2b_write <= 1'b1;
end
dqs_in_valid <= 1'b1;
wr_burst_length = bl_pipeline[2];
end
// read dqs enable counter
if (rd_pipeline[RDQSEN_PRE]) begin
rdqsen_cntr = RDQSEN_PRE + bl_pipeline[RDQSEN_PRE] + RDQSEN_PST - 1;
end
if (rdqsen_cntr > 0) begin
rdqsen_cntr = rdqsen_cntr - 1;
dqs_out_en = 1'b1;
end else begin
dqs_out_en = 1'b0;
end
// read dqs counter
if (rd_pipeline[RDQS_PRE]) begin
rdqs_cntr = RDQS_PRE + bl_pipeline[RDQS_PRE] + RDQS_PST - 1;
end
// read dqs
if (((rd_pipeline>>1 & {RDQS_PRE{1'b1}}) > 0) && (rdq_cntr == 0)) begin //read preamble
dqs_out = 1'b0;
end else if (rdqs_cntr > RDQS_PST) begin // read data
dqs_out = rdqs_cntr - RDQS_PST;
end else if (rdqs_cntr > 0) begin // read postamble
dqs_out = 1'b0;
end else begin
dqs_out = 1'b1;
end
if (rdqs_cntr > 0) begin
rdqs_cntr = rdqs_cntr - 1;
end
// read dq enable counter
if (rd_pipeline[RDQEN_PRE]) begin
rdqen_cntr = RDQEN_PRE + bl_pipeline[RDQEN_PRE] + RDQEN_PST;
end
if (rdqen_cntr > 0) begin
rdqen_cntr = rdqen_cntr - 1;
dq_out_en = 1'b1;
end else begin
dq_out_en = 1'b0;
end
// read dq
if (rd_pipeline[0]) begin
rdq_cntr = bl_pipeline[0];
end
if (rdq_cntr > 0) begin // read data
if (mpr_en) begin
`ifdef MPR_DQ0 // DQ0 output MPR data, other DQ low
if (mpr_select == 2'b00) begin // Calibration Pattern
dq_temp = {DQS_BITS{{`DQ_PER_DQS-1{1'b0}}, calibration_pattern[burst_position]}};
end else if (odts_readout && (mpr_select == 2'b11)) begin // Temp Sensor (ODTS)
dq_temp = {DQS_BITS{{`DQ_PER_DQS-1{1'b0}}, temp_sensor[burst_position]}};
end else begin // Reserved
dq_temp = {DQS_BITS{{`DQ_PER_DQS-1{1'b0}}, 1'bx}};
end
`else // all DQ output MPR data
if (mpr_select == 2'b00) begin // Calibration Pattern
dq_temp = {DQS_BITS{{`DQ_PER_DQS{calibration_pattern[burst_position]}}}};
end else if (odts_readout && (mpr_select == 2'b11)) begin // Temp Sensor (ODTS)
dq_temp = {DQS_BITS{{`DQ_PER_DQS{temp_sensor[burst_position]}}}};
end else begin // Reserved
dq_temp = {DQS_BITS{{`DQ_PER_DQS{1'bx}}}};
end
`endif
if (DEBUG) $display ("%m: at time %t READ @ DQS MultiPurpose Register %d, col = %d, data = %b", $time, mpr_select, burst_position, dq_temp[0]);
end else begin
dq_temp = memory_data>>(burst_position*DQ_BITS);
if (DEBUG) $display ("%m: at time %t INFO: READ @ DQS= bank = %h row = %h col = %h data = %h",$time, bank, row, (-1*BL_MAX & col) + burst_position, dq_temp);
end
dq_out = dq_temp;
rdq_cntr = rdq_cntr - 1;
end else begin
dq_out = {DQ_BITS{1'b1}};
end
// delay signals prior to output
if (RANDOM_OUT_DELAY && (dqs_out_en || (|dqs_out_en_dly) || dq_out_en || (|dq_out_en_dly))) begin
for (i=0; i<DQS_BITS; i=i+1) begin
// DQSCK requirements
// 1.) less than tDQSCK
// 2.) greater than -tDQSCK
// 3.) cannot change more than tQH + tDQSQ from previous DQS edge
dqsck_max = TDQSCK;
if (dqsck_max > dqsck[i] + TQH*tck_avg + TDQSQ) begin
dqsck_max = dqsck[i] + TQH*tck_avg + TDQSQ;
end
dqsck_min = -1*TDQSCK;
if (dqsck_min < dqsck[i] - TQH*tck_avg - TDQSQ) begin
dqsck_min = dqsck[i] - TQH*tck_avg - TDQSQ;
end
// DQSQ requirements
// 1.) less than tDQSQ
// 2.) greater than 0
// 3.) greater than tQH from the previous DQS edge
dqsq_min = 0;
if (dqsq_min < dqsck[i] - TQH*tck_avg) begin
dqsq_min = dqsck[i] - TQH*tck_avg;
end
if (dqsck_min == dqsck_max) begin
dqsck[i] = dqsck_min;
end else begin
dqsck[i] = $dist_uniform(seed, dqsck_min, dqsck_max);
end
dqsq_max = TDQSQ + dqsck[i];
dqs_out_en_dly[i] <= #(tck_avg/2) dqs_out_en;
dqs_out_dly[i] <= #(tck_avg/2 + dqsck[i]) dqs_out;
if (!write_levelization) begin
for (j=0; j<`DQ_PER_DQS; j=j+1) begin
dq_out_en_dly[i*`DQ_PER_DQS + j] <= #(tck_avg/2) dq_out_en;
if (dqsq_min == dqsq_max) begin
dq_out_dly [i*`DQ_PER_DQS + j] <= #(tck_avg/2 + dqsq_min) dq_out[i*`DQ_PER_DQS + j];
end else begin
dq_out_dly [i*`DQ_PER_DQS + j] <= #(tck_avg/2 + $dist_uniform(seed, dqsq_min, dqsq_max)) dq_out[i*`DQ_PER_DQS + j];
end
end
end
end
end else begin
out_delay = tck_avg/2;
dqs_out_en_dly <= #(out_delay) {DQS_BITS{dqs_out_en}};
dqs_out_dly <= #(out_delay) {DQS_BITS{dqs_out }};
if (write_levelization !== 1'b1) begin
dq_out_en_dly <= #(out_delay) {DQ_BITS {dq_out_en }};
dq_out_dly <= #(out_delay) {DQ_BITS {dq_out }};
end
end
end
endtask
always @ (posedge rst_n_in) begin : reset
integer i;
if (rst_n_in) begin
if ($time < 200000000 && check_strict_timing)
$display ("%m at time %t WARNING: 200 us is required before RST_N goes inactive.", $time);
if (cke_in !== 1'b0)
$display ("%m: at time %t ERROR: CKE must be inactive when RST_N goes inactive.", $time);
if ($time - tm_cke < 10000)
$display ("%m: at time %t ERROR: CKE must be maintained inactive for 10 ns before RST_N goes inactive.", $time);
// clear memory
`ifdef MAX_MEM
// verification group does not erase memory
// for (banki = 0; banki < `BANKS; banki = banki + 1) begin
// $fclose(memfd[banki]);
// memfd[banki] = open_bank_file(banki);
// end
`else
memory_used <= 0; //erase memory
`endif
end
end
always @(negedge rst_n_in or posedge diff_ck or negedge diff_ck) begin : main
integer i;
if (!rst_n_in) begin
reset_task;
end else begin
if (!in_self_refresh && (diff_ck !== 1'b0) && (diff_ck !== 1'b1))
$display ("%m: at time %t ERROR: CK and CK_N are not allowed to go to an unknown state.", $time);
data_task;
// Clock Frequency Change is legal:
// 1.) During Self Refresh
// 2.) During Precharge Power Down (DLL on or off)
if (in_self_refresh || (in_power_down && (active_bank == 0))) begin
if (diff_ck) begin
tjit_per_rtime = $time - tm_ck_pos - tck_avg;
end else begin
tjit_per_rtime = $time - tm_ck_neg - tck_avg;
end
if (dll_locked && (abs_value(tjit_per_rtime) > TJIT_PER)) begin
if ((tm_ck_pos - tm_cke_cmd < TCKSRE) || (ck_cntr - ck_cke_cmd < TCKSRE_TCK))
$display ("%m: at time %t ERROR: tCKSRE violation during Self Refresh or Precharge Power Down Entry", $time);
if (odt_state) begin
$display ("%m: at time %t ERROR: Clock Frequency Change Failure. ODT must be off prior to Clock Frequency Change.", $time);
if (STOP_ON_ERROR) $stop(0);
end else begin
if (DEBUG) $display ("%m: at time %t INFO: Clock Frequency Change detected. DLL Reset is Required.", $time);
tm_freq_change <= $time;
ck_freq_change <= ck_cntr;
dll_locked = 0;
end
end
end
if (diff_ck) begin
// check setup of command signals
if ($time > TIS) begin
if ($time - tm_cke < TIS)
$display ("%m: at time %t ERROR: tIS violation on CKE by %t", $time, tm_cke + TIS - $time);
if (cke_in) begin
for (i=0; i<22; i=i+1) begin
if ($time - tm_cmd_addr[i] < TIS)
$display ("%m: at time %t ERROR: tIS violation on %s by %t", $time, cmd_addr_string[i], tm_cmd_addr[i] + TIS - $time);
end
end
end
// update current state
if (dll_locked) begin
if (mr_chk == 0) begin
mr_chk = 1;
end else if (init_mode_reg[0] && (mr_chk == 1)) begin
// check CL value against the clock frequency
if (cas_latency*tck_avg < CL_TIME && check_strict_timing)
$display ("%m: at time %t ERROR: CAS Latency = %d is illegal @tCK(avg) = %f", $time, cas_latency, tck_avg);
// check WR value against the clock frequency
if (ceil(write_recovery*tck_avg) < TWR)
$display ("%m: at time %t ERROR: Write Recovery = %d is illegal @tCK(avg) = %f", $time, write_recovery, tck_avg);
// check the CWL value against the clock frequency
if (check_strict_timing) begin
case (cas_write_latency)
5 : if (tck_avg < 2500.0) $display ("%m: at time %t ERROR: CWL = %d is illegal @tCK(avg) = %f", $time, cas_write_latency, tck_avg);
6 : if ((tck_avg < 1875.0) || (tck_avg >= 2500.0)) $display ("%m: at time %t ERROR: CWL = %d is illegal @tCK(avg) = %f", $time, cas_write_latency, tck_avg);
7 : if ((tck_avg < 1500.0) || (tck_avg >= 1875.0)) $display ("%m: at time %t ERROR: CWL = %d is illegal @tCK(avg) = %f", $time, cas_write_latency, tck_avg);
8 : if ((tck_avg < 1250.0) || (tck_avg >= 1500.0)) $display ("%m: at time %t ERROR: CWL = %d is illegal @tCK(avg) = %f", $time, cas_write_latency, tck_avg);
9 : if ((tck_avg < 15e3/14) || (tck_avg >= 1250.0)) $display ("%m: at time %t ERROR: CWL = %d is illegal @tCK(avg) = %f", $time, cas_write_latency, tck_avg);
10: if ((tck_avg < 937.5) || (tck_avg >= 15e3/14)) $display ("%m: at time %t ERROR: CWL = %d is illegal @tCK(avg) = %f", $time, cas_write_latency, tck_avg);
default : $display ("%m: at time %t ERROR: CWL = %d is illegal @tCK(avg) = %f", $time, cas_write_latency, tck_avg);
endcase
// check the CL value against the clock frequency
if (!valid_cl(cas_latency, cas_write_latency))
$display ("%m: at time %t ERROR: CAS Latency = %d is not valid when CAS Write Latency = %d", $time, cas_latency, cas_write_latency);
end
mr_chk = 2;
end
end else if (!in_self_refresh) begin
mr_chk = 0;
if (ck_cntr - ck_dll_reset == TDLLK) begin
dll_locked = 1;
end
end
if (|auto_precharge_bank) begin
for (i=0; i<`BANKS; i=i+1) begin
// Write with Auto Precharge Calculation
// 1. Meet minimum tRAS requirement
// 2. Write Latency PLUS BL/2 cycles PLUS WR after Write command
if (write_precharge_bank[i]) begin
if ($time - tm_bank_activate[i] >= TRAS_MIN) begin
if (ck_cntr - ck_bank_write[i] >= write_latency + burst_length/2 + write_recovery) begin
if (DEBUG) $display ("%m: at time %t INFO: Auto Precharge bank %d", $time, i);
write_precharge_bank[i] = 0;
active_bank[i] = 0;
auto_precharge_bank[i] = 0;
tm_bank_precharge[i] = $time;
tm_precharge = $time;
ck_precharge = ck_cntr;
end
end
end
// Read with Auto Precharge Calculation
// 1. Meet minimum tRAS requirement
// 2. Additive Latency plus 4 cycles after Read command
// 3. tRTP after the last 8-bit prefetch
if (read_precharge_bank[i]) begin
if (($time - tm_bank_activate[i] >= TRAS_MIN) && (ck_cntr - ck_bank_read[i] >= additive_latency + TRTP_TCK)) begin
read_precharge_bank[i] = 0;
// In case the internal precharge is pushed out by tRTP, tRP starts at the point where
// the internal precharge happens (not at the next rising clock edge after this event).
if ($time - tm_bank_read_end[i] < TRTP) begin
if (DEBUG) $display ("%m: at time %t INFO: Auto Precharge bank %d", tm_bank_read_end[i] + TRTP, i);
active_bank[i] <= #(tm_bank_read_end[i] + TRTP - $time) 0;
auto_precharge_bank[i] <= #(tm_bank_read_end[i] + TRTP - $time) 0;
tm_bank_precharge[i] <= #(tm_bank_read_end[i] + TRTP - $time) tm_bank_read_end[i] + TRTP;
tm_precharge <= #(tm_bank_read_end[i] + TRTP - $time) tm_bank_read_end[i] + TRTP;
ck_precharge = ck_cntr;
end else begin
if (DEBUG) $display ("%m: at time %t INFO: Auto Precharge bank %d", $time, i);
active_bank[i] = 0;
auto_precharge_bank[i] = 0;
tm_bank_precharge[i] = $time;
tm_precharge = $time;
ck_precharge = ck_cntr;
end
end
end
end
end
// respond to incoming command
if (cke_in ^ prev_cke) begin
tm_cke_cmd <= $time;
ck_cke_cmd <= ck_cntr;
end
cmd_task(cke_in, cmd_n_in, ba_in, addr_in);
if ((cmd_n_in == WRITE) || (cmd_n_in == READ)) begin
al_pipeline[2*additive_latency] = 1'b1;
end
if (al_pipeline[0]) begin
// check tRCD after additive latency
if ((rd_pipeline[2*cas_latency - 1]) && ($time - tm_bank_activate[ba_pipeline[2*cas_latency - 1]] < TRCD))
$display ("%m: at time %t ERROR: tRCD violation during %s", $time, cmd_string[READ]);
if ((wr_pipeline[2*cas_write_latency + 1]) && ($time - tm_bank_activate[ba_pipeline[2*cas_write_latency + 1]] < TRCD))
$display ("%m: at time %t ERROR: tRCD violation during %s", $time, cmd_string[WRITE]);
// check tWTR after additive latency
if (rd_pipeline[2*cas_latency - 1]) begin //{
if (truebl4) begin //{
i = ba_pipeline[2*cas_latency - 1];
if ($time - tm_group_write_end[i[1]] < TWTR)
$display ("%m: at time %t ERROR: tWTR violation during %s", $time, cmd_string[READ]);
if ($time - tm_write_end < TWTR_DG)
$display ("%m: at time %t ERROR: tWTR_DG violation during %s", $time, cmd_string[READ]);
end else begin
if ($time - tm_write_end < TWTR)
$display ("%m: at time %t ERROR: tWTR violation during %s", $time, cmd_string[READ]);
end
end
end
if (rd_pipeline) begin
if (rd_pipeline[2*cas_latency - 1]) begin
tm_bank_read_end[ba_pipeline[2*cas_latency - 1]] <= $time;
end
end
for (i=0; i<`BANKS; i=i+1) begin
if ((ck_cntr - ck_bank_write[i] > write_latency) && (ck_cntr - ck_bank_write[i] <= write_latency + burst_length/2)) begin
tm_bank_write_end[i] <= $time;
tm_group_write_end[i[1]] <= $time;
tm_write_end <= $time;
end
end
// clk pin is disabled during self refresh
if (!in_self_refresh && tm_ck_pos ) begin
tjit_cc_time = $time - tm_ck_pos - tck_i;
tck_i = $time - tm_ck_pos;
tck_avg = tck_avg - tck_sample[ck_cntr%TDLLK]/$itor(TDLLK);
tck_avg = tck_avg + tck_i/$itor(TDLLK);
tck_sample[ck_cntr%TDLLK] = tck_i;
tjit_per_rtime = tck_i - tck_avg;
if (dll_locked && check_strict_timing) begin
// check accumulated error
terr_nper_rtime = 0;
for (i=0; i<12; i=i+1) begin
terr_nper_rtime = terr_nper_rtime + tck_sample[i] - tck_avg;
terr_nper_rtime = abs_value(terr_nper_rtime);
case (i)
0 :;
1 : if (terr_nper_rtime - TERR_2PER >= 1.0) $display ("%m: at time %t ERROR: tERR(2per) violation by %f ps.", $time, terr_nper_rtime - TERR_2PER);
2 : if (terr_nper_rtime - TERR_3PER >= 1.0) $display ("%m: at time %t ERROR: tERR(3per) violation by %f ps.", $time, terr_nper_rtime - TERR_3PER);
3 : if (terr_nper_rtime - TERR_4PER >= 1.0) $display ("%m: at time %t ERROR: tERR(4per) violation by %f ps.", $time, terr_nper_rtime - TERR_4PER);
4 : if (terr_nper_rtime - TERR_5PER >= 1.0) $display ("%m: at time %t ERROR: tERR(5per) violation by %f ps.", $time, terr_nper_rtime - TERR_5PER);
5 : if (terr_nper_rtime - TERR_6PER >= 1.0) $display ("%m: at time %t ERROR: tERR(6per) violation by %f ps.", $time, terr_nper_rtime - TERR_6PER);
6 : if (terr_nper_rtime - TERR_7PER >= 1.0) $display ("%m: at time %t ERROR: tERR(7per) violation by %f ps.", $time, terr_nper_rtime - TERR_7PER);
7 : if (terr_nper_rtime - TERR_8PER >= 1.0) $display ("%m: at time %t ERROR: tERR(8per) violation by %f ps.", $time, terr_nper_rtime - TERR_8PER);
8 : if (terr_nper_rtime - TERR_9PER >= 1.0) $display ("%m: at time %t ERROR: tERR(9per) violation by %f ps.", $time, terr_nper_rtime - TERR_9PER);
9 : if (terr_nper_rtime - TERR_10PER >= 1.0) $display ("%m: at time %t ERROR: tERR(10per) violation by %f ps.", $time, terr_nper_rtime - TERR_10PER);
10 : if (terr_nper_rtime - TERR_11PER >= 1.0) $display ("%m: at time %t ERROR: tERR(11per) violation by %f ps.", $time, terr_nper_rtime - TERR_11PER);
11 : if (terr_nper_rtime - TERR_12PER >= 1.0) $display ("%m: at time %t ERROR: tERR(12per) violation by %f ps.", $time, terr_nper_rtime - TERR_12PER);
endcase
end
// check tCK min/max/jitter
if (abs_value(tjit_per_rtime) - TJIT_PER >= 1.0)
$display ("%m: at time %t ERROR: tJIT(per) violation by %f ps.", $time, abs_value(tjit_per_rtime) - TJIT_PER);
if (abs_value(tjit_cc_time) - TJIT_CC >= 1.0)
$display ("%m: at time %t ERROR: tJIT(cc) violation by %f ps.", $time, abs_value(tjit_cc_time) - TJIT_CC);
if (TCK_MIN - tck_avg >= 1.0)
$display ("%m: at time %t ERROR: tCK(avg) minimum violation by %f ps.", $time, TCK_MIN - tck_avg);
if (tck_avg - TCK_MAX >= 1.0)
$display ("%m: at time %t ERROR: tCK(avg) maximum violation by %f ps.", $time, tck_avg - TCK_MAX);
// check tCL
if (tm_ck_neg - $time < TCL_ABS_MIN*tck_avg)
$display ("%m: at time %t ERROR: tCL(abs) minimum violation on CLK by %t", $time, TCL_ABS_MIN*tck_avg - tm_ck_neg + $time);
if (tcl_avg < TCL_AVG_MIN*tck_avg)
$display ("%m: at time %t ERROR: tCL(avg) minimum violation on CLK by %t", $time, TCL_AVG_MIN*tck_avg - tcl_avg);
if (tcl_avg > TCL_AVG_MAX*tck_avg)
$display ("%m: at time %t ERROR: tCL(avg) maximum violation on CLK by %t", $time, tcl_avg - TCL_AVG_MAX*tck_avg);
end
// calculate the tch avg jitter
tch_avg = tch_avg - tch_sample[ck_cntr%TDLLK]/$itor(TDLLK);
tch_avg = tch_avg + tch_i/$itor(TDLLK);
tch_sample[ck_cntr%TDLLK] = tch_i;
tjit_ch_rtime = tch_i - tch_avg;
duty_cycle = tch_avg/tck_avg;
// update timers/counters
tcl_i <= $time - tm_ck_neg;
end
prev_odt <= odt_in;
// update timers/counters
ck_cntr <= ck_cntr + 1;
tm_ck_pos = $time;
end else begin
// clk pin is disabled during self refresh
if (!in_self_refresh) begin
if (dll_locked && check_strict_timing) begin
if ($time - tm_ck_pos < TCH_ABS_MIN*tck_avg)
$display ("%m: at time %t ERROR: tCH(abs) minimum violation on CLK by %t", $time, TCH_ABS_MIN*tck_avg - $time + tm_ck_pos);
if (tch_avg < TCH_AVG_MIN*tck_avg)
$display ("%m: at time %t ERROR: tCH(avg) minimum violation on CLK by %t", $time, TCH_AVG_MIN*tck_avg - tch_avg);
if (tch_avg > TCH_AVG_MAX*tck_avg)
$display ("%m: at time %t ERROR: tCH(avg) maximum violation on CLK by %t", $time, tch_avg - TCH_AVG_MAX*tck_avg);
end
// calculate the tcl avg jitter
tcl_avg = tcl_avg - tcl_sample[ck_cntr%TDLLK]/$itor(TDLLK);
tcl_avg = tcl_avg + tcl_i/$itor(TDLLK);
tcl_sample[ck_cntr%TDLLK] = tcl_i;
// update timers/counters
tch_i <= $time - tm_ck_pos;
end
tm_ck_neg = $time;
end
// on die termination
if (odt_en || dyn_odt_en) begin
// odt pin is disabled during self refresh
if (!in_self_refresh && diff_ck) begin
if ($time - tm_odt < TIS)
$display ("%m: at time %t ERROR: tIS violation on ODT by %t", $time, tm_odt + TIS - $time);
if (prev_odt ^ odt_in) begin
if (!dll_locked)
$display ("%m: at time %t WARNING: tDLLK violation during ODT transition.", $time);
if (($time - tm_load_mode < TMOD) || (ck_cntr - ck_load_mode < TMOD_TCK))
$display ("%m: at time %t ERROR: tMOD violation during ODT transition", $time);
if (ck_cntr - ck_zqinit < TZQINIT)
$display ("%m: at time %t ERROR: TZQinit violation during ODT transition", $time);
if (ck_cntr - ck_zqoper < TZQOPER)
$display ("%m: at time %t ERROR: TZQoper violation during ODT transition", $time);
if (ck_cntr - ck_zqcs < TZQCS)
$display ("%m: at time %t ERROR: tZQcs violation during ODT transition", $time);
// if (($time - tm_slow_exit_pd < TXPDLL) || (ck_cntr - ck_slow_exit_pd < TXPDLL_TCK))
// $display ("%m: at time %t ERROR: tXPDLL violation during ODT transition", $time);
if (ck_cntr - ck_self_refresh < TXSDLL)
$display ("%m: at time %t ERROR: tXSDLL violation during ODT transition", $time);
if (in_self_refresh)
$display ("%m: at time %t ERROR: Illegal ODT transition during Self Refresh.", $time);
if (!odt_in && (ck_cntr - ck_odt < ODTH4))
$display ("%m: at time %t ERROR: ODTH4 violation during ODT transition", $time);
if (!odt_in && (ck_cntr - ck_odth8 < ODTH8))
$display ("%m: at time %t ERROR: ODTH8 violation during ODT transition", $time);
if (($time - tm_slow_exit_pd < TXPDLL) || (ck_cntr - ck_slow_exit_pd < TXPDLL_TCK))
$display ("%m: at time %t WARNING: tXPDLL during ODT transition. Synchronous or asynchronous change in termination resistance is possible.", $time);
// async ODT mode applies:
// 1.) during precharge power down with DLL off
// 2.) if tANPD has not been satisfied
// 3.) until tXPDLL has been satisfied
if ((in_power_down && low_power && (active_bank == 0)) || ($time - tm_slow_exit_pd < TXPDLL) || (ck_cntr - ck_slow_exit_pd < TXPDLL_TCK)) begin
odt_state = odt_in;
if (DEBUG && odt_en) $display ("%m: at time %t INFO: Async On Die Termination Rtt_NOM = %d Ohm", $time, {32{odt_state}} & get_rtt_nom(odt_rtt_nom));
if (odt_state) begin
odt_state_dly <= #(TAONPD) odt_state;
end else begin
odt_state_dly <= #(TAOFPD) odt_state;
end
// sync ODT mode applies:
// 1.) during normal operation
// 2.) during active power down
// 3.) during precharge power down with DLL on
end else begin
odt_pipeline[2*(write_latency - 2)] = 1'b1; // ODTLon, ODTLoff
end
ck_odt <= ck_cntr;
end
end
if (odt_pipeline[0]) begin
odt_state = ~odt_state;
if (DEBUG && odt_en) $display ("%m: at time %t INFO: Sync On Die Termination Rtt_NOM = %d Ohm", $time, {32{odt_state}} & get_rtt_nom(odt_rtt_nom));
if (odt_state) begin
odt_state_dly <= #(TAON) odt_state;
end else begin
odt_state_dly <= #(TAOF*tck_avg) odt_state;
end
end
if (rd_pipeline[RDQSEN_PRE]) begin
odt_cntr = 1 + RDQSEN_PRE + bl_pipeline[RDQSEN_PRE] + RDQSEN_PST - 1;
end
if (odt_cntr > 0) begin
if (odt_state) begin
$display ("%m: at time %t ERROR: On Die Termination must be OFF during Read data transfer.", $time);
end
odt_cntr = odt_cntr - 1;
end
if (dyn_odt_en && odt_state) begin
if (DEBUG && (dyn_odt_state ^ dyn_odt_pipeline[0]))
$display ("%m: at time %t INFO: Sync On Die Termination Rtt_WR = %d Ohm", $time, {32{dyn_odt_pipeline[0]}} & get_rtt_wr(odt_rtt_wr));
dyn_odt_state = dyn_odt_pipeline[0];
end
dyn_odt_state_dly <= #(TADC*tck_avg) dyn_odt_state;
end
if (cke_in && write_levelization) begin
for (i=0; i<DQS_BITS; i=i+1) begin
if ($time - tm_dqs_pos[i] < TWLH)
$display ("%m: at time %t WARNING: tWLH violation on DQS bit %d positive edge. Indeterminate CK capture is possible.", $time, i);
end
end
// shift pipelines
if (|wr_pipeline || |rd_pipeline || |al_pipeline) begin
al_pipeline = al_pipeline>>1;
wr_pipeline = wr_pipeline>>1;
rd_pipeline = rd_pipeline>>1;
for (i=0; i<`MAX_PIPE; i=i+1) begin
bl_pipeline[i] = bl_pipeline[i+1];
ba_pipeline[i] = ba_pipeline[i+1];
row_pipeline[i] = row_pipeline[i+1];
col_pipeline[i] = col_pipeline[i+1];
end
end
if (|odt_pipeline || |dyn_odt_pipeline) begin
odt_pipeline = odt_pipeline>>1;
dyn_odt_pipeline = dyn_odt_pipeline>>1;
end
end
end
// receiver(s)
task dqs_even_receiver;
input [3:0] i;
reg [63:0] bit_mask;
begin
bit_mask = {`DQ_PER_DQS{1'b1}}<<(i*`DQ_PER_DQS);
if (dqs_even[i]) begin
if (tdqs_en) begin // tdqs disables dm
dm_in_pos[i] = 1'b0;
end else begin
dm_in_pos[i] = dm_in[i];
end
dq_in_pos = (dq_in & bit_mask) | (dq_in_pos & ~bit_mask);
end
end
endtask
always @(posedge dqs_even[ 0]) dqs_even_receiver( 0);
always @(posedge dqs_even[ 1]) dqs_even_receiver( 1);
always @(posedge dqs_even[ 2]) dqs_even_receiver( 2);
always @(posedge dqs_even[ 3]) dqs_even_receiver( 3);
always @(posedge dqs_even[ 4]) dqs_even_receiver( 4);
always @(posedge dqs_even[ 5]) dqs_even_receiver( 5);
always @(posedge dqs_even[ 6]) dqs_even_receiver( 6);
always @(posedge dqs_even[ 7]) dqs_even_receiver( 7);
always @(posedge dqs_even[ 8]) dqs_even_receiver( 8);
always @(posedge dqs_even[ 9]) dqs_even_receiver( 9);
always @(posedge dqs_even[10]) dqs_even_receiver(10);
always @(posedge dqs_even[11]) dqs_even_receiver(11);
always @(posedge dqs_even[12]) dqs_even_receiver(12);
always @(posedge dqs_even[13]) dqs_even_receiver(13);
always @(posedge dqs_even[14]) dqs_even_receiver(14);
always @(posedge dqs_even[15]) dqs_even_receiver(15);
task dqs_odd_receiver;
input [3:0] i;
reg [63:0] bit_mask;
begin
bit_mask = {`DQ_PER_DQS{1'b1}}<<(i*`DQ_PER_DQS);
if (dqs_odd[i]) begin
if (tdqs_en) begin // tdqs disables dm
dm_in_neg[i] = 1'b0;
end else begin
dm_in_neg[i] = dm_in[i];
end
dq_in_neg = (dq_in & bit_mask) | (dq_in_neg & ~bit_mask);
end
end
endtask
always @(posedge dqs_odd[ 0]) dqs_odd_receiver( 0);
always @(posedge dqs_odd[ 1]) dqs_odd_receiver( 1);
always @(posedge dqs_odd[ 2]) dqs_odd_receiver( 2);
always @(posedge dqs_odd[ 3]) dqs_odd_receiver( 3);
always @(posedge dqs_odd[ 4]) dqs_odd_receiver( 4);
always @(posedge dqs_odd[ 5]) dqs_odd_receiver( 5);
always @(posedge dqs_odd[ 6]) dqs_odd_receiver( 6);
always @(posedge dqs_odd[ 7]) dqs_odd_receiver( 7);
always @(posedge dqs_odd[ 8]) dqs_odd_receiver( 8);
always @(posedge dqs_odd[ 9]) dqs_odd_receiver( 9);
always @(posedge dqs_odd[10]) dqs_odd_receiver(10);
always @(posedge dqs_odd[11]) dqs_odd_receiver(11);
always @(posedge dqs_odd[12]) dqs_odd_receiver(12);
always @(posedge dqs_odd[13]) dqs_odd_receiver(13);
always @(posedge dqs_odd[14]) dqs_odd_receiver(14);
always @(posedge dqs_odd[15]) dqs_odd_receiver(15);
// Processes to check hold and pulse width of control signals
always @(posedge rst_n_in) begin
if ($time > 100000) begin
if (tm_rst_n + 100000 > $time)
$display ("%m: at time %t ERROR: RST_N pulse width violation by %t", $time, tm_rst_n + 100000 - $time);
end
tm_rst_n = $time;
end
always @(cke_in) begin
if (rst_n_in) begin
if ($time > TIH) begin
if ($time - tm_ck_pos < TIH)
$display ("%m: at time %t ERROR: tIH violation on CKE by %t", $time, tm_ck_pos + TIH - $time);
end
if ($time - tm_cke < TIPW)
$display ("%m: at time %t ERROR: tIPW violation on CKE by %t", $time, tm_cke + TIPW - $time);
end
tm_cke = $time;
end
always @(odt_in) begin
if (rst_n_in && odt_en && !in_self_refresh) begin
if ($time - tm_ck_pos < TIH)
$display ("%m: at time %t ERROR: tIH violation on ODT by %t", $time, tm_ck_pos + TIH - $time);
if ($time - tm_odt < TIPW)
$display ("%m: at time %t ERROR: tIPW violation on ODT by %t", $time, tm_odt + TIPW - $time);
end
tm_odt = $time;
end
task cmd_addr_timing_check;
input i;
reg [4:0] i;
begin
if (rst_n_in && prev_cke) begin
if ((i == 0) && ($time - tm_ck_pos < TIH)) // always check tIH for CS#
$display ("%m: at time %t ERROR: tIH violation on %s by %t", $time, cmd_addr_string[i], tm_ck_pos + TIH - $time);
if ((i > 0) && (cs_n_in == 0) &&($time - tm_ck_pos < TIH)) // Only check tIH for cmd_addr if CS# is low
$display ("%m: at time %t ERROR: tIH violation on %s by %t", $time, cmd_addr_string[i], tm_ck_pos + TIH - $time);
if ($time - tm_cmd_addr[i] < TIPW)
$display ("%m: at time %t ERROR: tIPW violation on %s by %t", $time, cmd_addr_string[i], tm_cmd_addr[i] + TIPW - $time);
end
tm_cmd_addr[i] = $time;
end
endtask
always @(cs_n_in ) cmd_addr_timing_check( 0);
always @(ras_n_in ) cmd_addr_timing_check( 1);
always @(cas_n_in ) cmd_addr_timing_check( 2);
always @(we_n_in ) cmd_addr_timing_check( 3);
always @(ba_in [ 0]) cmd_addr_timing_check( 4);
always @(ba_in [ 1]) cmd_addr_timing_check( 5);
always @(ba_in [ 2]) cmd_addr_timing_check( 6);
always @(addr_in[ 0]) cmd_addr_timing_check( 7);
always @(addr_in[ 1]) cmd_addr_timing_check( 8);
always @(addr_in[ 2]) cmd_addr_timing_check( 9);
always @(addr_in[ 3]) cmd_addr_timing_check(10);
always @(addr_in[ 4]) cmd_addr_timing_check(11);
always @(addr_in[ 5]) cmd_addr_timing_check(12);
always @(addr_in[ 6]) cmd_addr_timing_check(13);
always @(addr_in[ 7]) cmd_addr_timing_check(14);
always @(addr_in[ 8]) cmd_addr_timing_check(15);
always @(addr_in[ 9]) cmd_addr_timing_check(16);
always @(addr_in[10]) cmd_addr_timing_check(17);
always @(addr_in[11]) cmd_addr_timing_check(18);
always @(addr_in[12]) cmd_addr_timing_check(19);
always @(addr_in[13]) cmd_addr_timing_check(20);
always @(addr_in[14]) cmd_addr_timing_check(21);
always @(addr_in[15]) cmd_addr_timing_check(22);
// Processes to check setup and hold of data signals
task dm_timing_check;
input i;
reg [3:0] i;
begin
if (dqs_in_valid) begin
if ($time - tm_dqs[i] < TDH)
$display ("%m: at time %t ERROR: tDH violation on DM bit %d by %t", $time, i, tm_dqs[i] + TDH - $time);
if (check_dm_tdipw[i]) begin
if ($time - tm_dm[i] < TDIPW)
$display ("%m: at time %t ERROR: tDIPW violation on DM bit %d by %t", $time, i, tm_dm[i] + TDIPW - $time);
end
end
check_dm_tdipw[i] <= 1'b0;
tm_dm[i] = $time;
end
endtask
always @(dm_in[ 0]) dm_timing_check( 0);
always @(dm_in[ 1]) dm_timing_check( 1);
always @(dm_in[ 2]) dm_timing_check( 2);
always @(dm_in[ 3]) dm_timing_check( 3);
always @(dm_in[ 4]) dm_timing_check( 4);
always @(dm_in[ 5]) dm_timing_check( 5);
always @(dm_in[ 6]) dm_timing_check( 6);
always @(dm_in[ 7]) dm_timing_check( 7);
always @(dm_in[ 8]) dm_timing_check( 8);
always @(dm_in[ 9]) dm_timing_check( 9);
always @(dm_in[10]) dm_timing_check(10);
always @(dm_in[11]) dm_timing_check(11);
always @(dm_in[12]) dm_timing_check(12);
always @(dm_in[13]) dm_timing_check(13);
always @(dm_in[14]) dm_timing_check(14);
always @(dm_in[15]) dm_timing_check(15);
task dq_timing_check;
input i;
reg [5:0] i;
begin
if (dqs_in_valid) begin
if ($time - tm_dqs[i/`DQ_PER_DQS] < TDH)
$display ("%m: at time %t ERROR: tDH violation on DQ bit %d by %t", $time, i, tm_dqs[i/`DQ_PER_DQS] + TDH - $time);
if (check_dq_tdipw[i]) begin
if ($time - tm_dq[i] < TDIPW)
$display ("%m: at time %t ERROR: tDIPW violation on DQ bit %d by %t", $time, i, tm_dq[i] + TDIPW - $time);
end
end
check_dq_tdipw[i] <= 1'b0;
tm_dq[i] = $time;
end
endtask
always @(dq_in[ 0]) dq_timing_check( 0);
always @(dq_in[ 1]) dq_timing_check( 1);
always @(dq_in[ 2]) dq_timing_check( 2);
always @(dq_in[ 3]) dq_timing_check( 3);
always @(dq_in[ 4]) dq_timing_check( 4);
always @(dq_in[ 5]) dq_timing_check( 5);
always @(dq_in[ 6]) dq_timing_check( 6);
always @(dq_in[ 7]) dq_timing_check( 7);
always @(dq_in[ 8]) dq_timing_check( 8);
always @(dq_in[ 9]) dq_timing_check( 9);
always @(dq_in[10]) dq_timing_check(10);
always @(dq_in[11]) dq_timing_check(11);
always @(dq_in[12]) dq_timing_check(12);
always @(dq_in[13]) dq_timing_check(13);
always @(dq_in[14]) dq_timing_check(14);
always @(dq_in[15]) dq_timing_check(15);
always @(dq_in[16]) dq_timing_check(16);
always @(dq_in[17]) dq_timing_check(17);
always @(dq_in[18]) dq_timing_check(18);
always @(dq_in[19]) dq_timing_check(19);
always @(dq_in[20]) dq_timing_check(20);
always @(dq_in[21]) dq_timing_check(21);
always @(dq_in[22]) dq_timing_check(22);
always @(dq_in[23]) dq_timing_check(23);
always @(dq_in[24]) dq_timing_check(24);
always @(dq_in[25]) dq_timing_check(25);
always @(dq_in[26]) dq_timing_check(26);
always @(dq_in[27]) dq_timing_check(27);
always @(dq_in[28]) dq_timing_check(28);
always @(dq_in[29]) dq_timing_check(29);
always @(dq_in[30]) dq_timing_check(30);
always @(dq_in[31]) dq_timing_check(31);
always @(dq_in[32]) dq_timing_check(32);
always @(dq_in[33]) dq_timing_check(33);
always @(dq_in[34]) dq_timing_check(34);
always @(dq_in[35]) dq_timing_check(35);
always @(dq_in[36]) dq_timing_check(36);
always @(dq_in[37]) dq_timing_check(37);
always @(dq_in[38]) dq_timing_check(38);
always @(dq_in[39]) dq_timing_check(39);
always @(dq_in[40]) dq_timing_check(40);
always @(dq_in[41]) dq_timing_check(41);
always @(dq_in[42]) dq_timing_check(42);
always @(dq_in[43]) dq_timing_check(43);
always @(dq_in[44]) dq_timing_check(44);
always @(dq_in[45]) dq_timing_check(45);
always @(dq_in[46]) dq_timing_check(46);
always @(dq_in[47]) dq_timing_check(47);
always @(dq_in[48]) dq_timing_check(48);
always @(dq_in[49]) dq_timing_check(49);
always @(dq_in[50]) dq_timing_check(50);
always @(dq_in[51]) dq_timing_check(51);
always @(dq_in[52]) dq_timing_check(52);
always @(dq_in[53]) dq_timing_check(53);
always @(dq_in[54]) dq_timing_check(54);
always @(dq_in[55]) dq_timing_check(55);
always @(dq_in[56]) dq_timing_check(56);
always @(dq_in[57]) dq_timing_check(57);
always @(dq_in[58]) dq_timing_check(58);
always @(dq_in[59]) dq_timing_check(59);
always @(dq_in[60]) dq_timing_check(60);
always @(dq_in[61]) dq_timing_check(61);
always @(dq_in[62]) dq_timing_check(62);
always @(dq_in[63]) dq_timing_check(63);
task dqs_pos_timing_check;
input i;
reg [4:0] i;
reg [3:0] j;
begin
if (write_levelization && i<16) begin
if (ck_cntr - ck_load_mode < TWLMRD)
$display ("%m: at time %t ERROR: tWLMRD violation on DQS bit %d positive edge.", $time, i);
if (($time - tm_ck_pos < TWLS) || ($time - tm_ck_neg < TWLS))
$display ("%m: at time %t WARNING: tWLS violation on DQS bit %d positive edge. Indeterminate CK capture is possible.", $time, i);
if (DEBUG)
$display ("%m: at time %t Write Leveling @ DQS ck = %b", $time, diff_ck);
dq_out_en_dly[i*`DQ_PER_DQS] <= #(TWLO) 1'b1;
dq_out_dly[i*`DQ_PER_DQS] <= #(TWLO) diff_ck;
for (j=1; j<`DQ_PER_DQS; j=j+1) begin
dq_out_en_dly[i*`DQ_PER_DQS+j] <= #(TWLO + TWLOE) 1'b1;
dq_out_dly[i*`DQ_PER_DQS+j] <= #(TWLO + TWLOE) 1'b0;
end
end
if (dqs_in_valid && ((wdqs_pos_cntr[i] < wr_burst_length/2) || b2b_write)) begin
if (dqs_in[i] ^ prev_dqs_in[i]) begin
if (dll_locked) begin
if (check_write_preamble[i]) begin
if ($time - tm_dqs_pos[i] < $rtoi(TWPRE*tck_avg))
$display ("%m: at time %t ERROR: tWPRE violation on &s bit %d", $time, dqs_string[i/16], i%16);
end else if (check_write_postamble[i]) begin
if ($time - tm_dqs_neg[i] < $rtoi(TWPST*tck_avg))
$display ("%m: at time %t ERROR: tWPST violation on %s bit %d", $time, dqs_string[i/16], i%16);
end else begin
if ($time - tm_dqs_neg[i] < $rtoi(TDQSL*tck_avg))
$display ("%m: at time %t ERROR: tDQSL violation on %s bit %d", $time, dqs_string[i/16], i%16);
end
end
if ($time - tm_dm[i%16] < TDS)
$display ("%m: at time %t ERROR: tDS violation on DM bit %d by %t", $time, i, tm_dm[i%16] + TDS - $time);
if (!dq_out_en) begin
for (j=0; j<`DQ_PER_DQS; j=j+1) begin
if ($time - tm_dq[(i%16)*`DQ_PER_DQS+j] < TDS)
$display ("%m: at time %t ERROR: tDS violation on DQ bit %d by %t", $time, i*`DQ_PER_DQS+j, tm_dq[(i%16)*`DQ_PER_DQS+j] + TDS - $time);
check_dq_tdipw[(i%16)*`DQ_PER_DQS+j] <= 1'b1;
end
end
if ((wdqs_pos_cntr[i] < wr_burst_length/2) && !b2b_write) begin
wdqs_pos_cntr[i] <= wdqs_pos_cntr[i] + 1;
end else begin
wdqs_pos_cntr[i] <= 1;
end
check_dm_tdipw[i%16] <= 1'b1;
check_write_preamble[i] <= 1'b0;
check_write_postamble[i] <= 1'b0;
check_write_dqs_low[i] <= 1'b0;
tm_dqs[i%16] <= $time;
end else begin
$display ("%m: at time %t ERROR: Invalid latching edge on %s bit %d", $time, dqs_string[i/16], i%16);
end
end
tm_dqss_pos[i] <= $time;
tm_dqs_pos[i] = $time;
prev_dqs_in[i] <= dqs_in[i];
end
endtask
always @(posedge dqs_in[ 0]) dqs_pos_timing_check( 0);
always @(posedge dqs_in[ 1]) dqs_pos_timing_check( 1);
always @(posedge dqs_in[ 2]) dqs_pos_timing_check( 2);
always @(posedge dqs_in[ 3]) dqs_pos_timing_check( 3);
always @(posedge dqs_in[ 4]) dqs_pos_timing_check( 4);
always @(posedge dqs_in[ 5]) dqs_pos_timing_check( 5);
always @(posedge dqs_in[ 6]) dqs_pos_timing_check( 6);
always @(posedge dqs_in[ 7]) dqs_pos_timing_check( 7);
always @(posedge dqs_in[ 8]) dqs_pos_timing_check( 8);
always @(posedge dqs_in[ 9]) dqs_pos_timing_check( 9);
always @(posedge dqs_in[10]) dqs_pos_timing_check(10);
always @(posedge dqs_in[11]) dqs_pos_timing_check(11);
always @(posedge dqs_in[12]) dqs_pos_timing_check(12);
always @(posedge dqs_in[13]) dqs_pos_timing_check(13);
always @(posedge dqs_in[14]) dqs_pos_timing_check(14);
always @(posedge dqs_in[15]) dqs_pos_timing_check(15);
always @(negedge dqs_in[16]) dqs_pos_timing_check(16);
always @(negedge dqs_in[17]) dqs_pos_timing_check(17);
always @(negedge dqs_in[18]) dqs_pos_timing_check(18);
always @(negedge dqs_in[19]) dqs_pos_timing_check(19);
always @(negedge dqs_in[20]) dqs_pos_timing_check(20);
always @(negedge dqs_in[21]) dqs_pos_timing_check(21);
always @(negedge dqs_in[22]) dqs_pos_timing_check(22);
always @(negedge dqs_in[23]) dqs_pos_timing_check(23);
always @(negedge dqs_in[24]) dqs_pos_timing_check(24);
always @(negedge dqs_in[25]) dqs_pos_timing_check(25);
always @(negedge dqs_in[26]) dqs_pos_timing_check(26);
always @(negedge dqs_in[27]) dqs_pos_timing_check(27);
always @(negedge dqs_in[28]) dqs_pos_timing_check(28);
always @(negedge dqs_in[29]) dqs_pos_timing_check(29);
always @(negedge dqs_in[30]) dqs_pos_timing_check(30);
always @(negedge dqs_in[31]) dqs_pos_timing_check(31);
task dqs_neg_timing_check;
input i;
reg [4:0] i;
reg [3:0] j;
begin
if (write_levelization && i<16) begin
if (ck_cntr - ck_load_mode < TWLDQSEN)
$display ("%m: at time %t ERROR: tWLDQSEN violation on DQS bit %d.", $time, i);
if ($time - tm_dqs_pos[i] < $rtoi(TDQSH*tck_avg))
$display ("%m: at time %t ERROR: tDQSH violation on DQS bit %d by %t", $time, i, tm_dqs_pos[i] + TDQSH*tck_avg - $time);
end
if (dqs_in_valid && (wdqs_pos_cntr[i] > 0) && check_write_dqs_high[i]) begin
if (dqs_in[i] ^ prev_dqs_in[i]) begin
if (dll_locked) begin
if ($time - tm_dqs_pos[i] < $rtoi(TDQSH*tck_avg))
$display ("%m: at time %t ERROR: tDQSH violation on %s bit %d", $time, dqs_string[i/16], i%16);
if ($time - tm_ck_pos < $rtoi(TDSH*tck_avg))
$display ("%m: at time %t ERROR: tDSH violation on %s bit %d", $time, dqs_string[i/16], i%16);
end
if ($time - tm_dm[i%16] < TDS)
$display ("%m: at time %t ERROR: tDS violation on DM bit %d by %t", $time, i, tm_dm[i%16] + TDS - $time);
if (!dq_out_en) begin
for (j=0; j<`DQ_PER_DQS; j=j+1) begin
if ($time - tm_dq[(i%16)*`DQ_PER_DQS+j] < TDS)
$display ("%m: at time %t ERROR: tDS violation on DQ bit %d by %t", $time, i*`DQ_PER_DQS+j, tm_dq[(i%16)*`DQ_PER_DQS+j] + TDS - $time);
check_dq_tdipw[(i%16)*`DQ_PER_DQS+j] <= 1'b1;
end
end
check_dm_tdipw[i%16] <= 1'b1;
tm_dqs[i%16] <= $time;
end else begin
$display ("%m: at time %t ERROR: Invalid latching edge on %s bit %d", $time, dqs_string[i/16], i%16);
end
end
check_write_dqs_high[i] <= 1'b0;
tm_dqs_neg[i] = $time;
prev_dqs_in[i] <= dqs_in[i];
end
endtask
always @(negedge dqs_in[ 0]) dqs_neg_timing_check( 0);
always @(negedge dqs_in[ 1]) dqs_neg_timing_check( 1);
always @(negedge dqs_in[ 2]) dqs_neg_timing_check( 2);
always @(negedge dqs_in[ 3]) dqs_neg_timing_check( 3);
always @(negedge dqs_in[ 4]) dqs_neg_timing_check( 4);
always @(negedge dqs_in[ 5]) dqs_neg_timing_check( 5);
always @(negedge dqs_in[ 6]) dqs_neg_timing_check( 6);
always @(negedge dqs_in[ 7]) dqs_neg_timing_check( 7);
always @(negedge dqs_in[ 8]) dqs_neg_timing_check( 8);
always @(negedge dqs_in[ 9]) dqs_neg_timing_check( 9);
always @(negedge dqs_in[10]) dqs_neg_timing_check(10);
always @(negedge dqs_in[11]) dqs_neg_timing_check(11);
always @(negedge dqs_in[12]) dqs_neg_timing_check(12);
always @(negedge dqs_in[13]) dqs_neg_timing_check(13);
always @(negedge dqs_in[14]) dqs_neg_timing_check(14);
always @(negedge dqs_in[15]) dqs_neg_timing_check(15);
always @(posedge dqs_in[16]) dqs_neg_timing_check(16);
always @(posedge dqs_in[17]) dqs_neg_timing_check(17);
always @(posedge dqs_in[18]) dqs_neg_timing_check(18);
always @(posedge dqs_in[19]) dqs_neg_timing_check(19);
always @(posedge dqs_in[20]) dqs_neg_timing_check(20);
always @(posedge dqs_in[21]) dqs_neg_timing_check(21);
always @(posedge dqs_in[22]) dqs_neg_timing_check(22);
always @(posedge dqs_in[23]) dqs_neg_timing_check(23);
always @(posedge dqs_in[24]) dqs_neg_timing_check(24);
always @(posedge dqs_in[25]) dqs_neg_timing_check(25);
always @(posedge dqs_in[26]) dqs_neg_timing_check(26);
always @(posedge dqs_in[27]) dqs_neg_timing_check(27);
always @(posedge dqs_in[28]) dqs_neg_timing_check(28);
always @(posedge dqs_in[29]) dqs_neg_timing_check(29);
always @(posedge dqs_in[30]) dqs_neg_timing_check(30);
always @(posedge dqs_in[31]) dqs_neg_timing_check(31);
endmodule
除了仿真文件还有参数文件，如下：
这里由于空间原因不再给出源代码，其中上面两个最大的程序是DDR example中自带的文件并不需要我们手写，因为第一次写该DDR所以这里给出一些源代码。
仿真结果
运行MODELSIM可以看到如下结果：
其中c3_calib_done拉高证明该仿真平台搭建正确。接下来的文章将给出读写时序，我们会发现ISE的MIG操作起来要比VIVADO简单很多。
结束语
对文章有什么看法或者需要更近一步交流的同学，可以加入下面的群：
