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//////////////////////////////////////////////////////////////////////

////                                                              ////

////  OR1200 Top Level                                            ////

////                                                              ////

////  This file is part of the OpenRISC 1200 project              ////

////  http://opencores.org/project,or1k                           ////

////                                                              ////

////  Description                                                 ////

////  OR1200 Top Level                                            ////

////                                                              ////

////  To Do:                                                      ////

////   - make it smaller and faster                               ////

////                                                              ////

////  Author(s):                                                  ////

////      - Damjan Lampret, lampret@opencores.org                 ////

////                                                              ////

//////////////////////////////////////////////////////////////////////

////                                                              ////

//// Copyright (C) 2000 Authors and OPENCORES.ORG                 ////

////                                                              ////

//// This source file may be used and distributed without         ////

//// restriction provided that this copyright statement is not    ////

//// removed from the file and that any derivative work contains  ////

//// the original copyright notice and the associated disclaimer. ////

////                                                              ////

//// This source file is free software; you can redistribute it   ////

//// and/or modify it under the terms of the GNU Lesser General   ////

//// Public License as published by the Free Software Foundation; ////

//// either version 2.1 of the License, or (at your option) any   ////

//// later version.                                               ////

////                                                              ////

//// This source is distributed in the hope that it will be       ////

//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////

//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////

//// PURPOSE.  See the GNU Lesser General Public License for more ////

//// details.                                                     ////

////                                                              ////

//// You should have received a copy of the GNU Lesser General    ////

//// Public License along with this source; if not, download it   ////

//// from http://www.opencores.org/lgpl.shtml                     ////

////                                                              ////

//////////////////////////////////////////////////////////////////////

//

// CVS Revision History

//

// $Log: or1200_top.v,v $

// Revision 2.0  2010/06/30 11:00:00  ORSoC

// Major update: 

// Structure reordered. 

//

// synopsys translate_off

`include "timescale.v"

// synopsys translate_on

`include "or1200_defines.v"

module or1200_top(

        // System

        clk_i, rst_i, pic_ints_i, clmode_i,

        // Instruction WISHBONE INTERFACE

        iwb_clk_i, iwb_rst_i, iwb_ack_i, iwb_err_i, iwb_rty_i, iwb_dat_i,

        iwb_cyc_o, iwb_adr_o, iwb_stb_o, iwb_we_o, iwb_sel_o, iwb_dat_o,

`ifdef OR1200_WB_CAB

        iwb_cab_o,

`endif

`ifdef OR1200_WB_B3

        iwb_cti_o, iwb_bte_o,

`endif

        // Data WISHBONE INTERFACE

        dwb_clk_i, dwb_rst_i, dwb_ack_i, dwb_err_i, dwb_rty_i, dwb_dat_i,

        dwb_cyc_o, dwb_adr_o, dwb_stb_o, dwb_we_o, dwb_sel_o, dwb_dat_o,

`ifdef OR1200_WB_CAB

        dwb_cab_o,

`endif

`ifdef OR1200_WB_B3

        dwb_cti_o, dwb_bte_o,

`endif

        // External Debug Interface

        dbg_stall_i, dbg_ewt_i, dbg_lss_o, dbg_is_o, dbg_wp_o, dbg_bp_o,

        dbg_stb_i, dbg_we_i, dbg_adr_i, dbg_dat_i, dbg_dat_o, dbg_ack_o,

`ifdef OR1200_BIST

        // RAM BIST

        mbist_si_i, mbist_so_o, mbist_ctrl_i,

`endif

        // Power Management

        pm_cpustall_i,

        pm_clksd_o, pm_dc_gate_o, pm_ic_gate_o, pm_dmmu_gate_o,

        pm_immu_gate_o, pm_tt_gate_o, pm_cpu_gate_o, pm_wakeup_o, pm_lvolt_o

,sig_tick

);

parameter dw = `OR1200_OPERAND_WIDTH;

parameter aw = `OR1200_OPERAND_WIDTH;

parameter ppic_ints = `OR1200_PIC_INTS;

//

// I/O

//

//

// System

//

input                   clk_i;

input                   rst_i;

input   [1:0]            clmode_i;       // 00 WB=RISC, 01 WB=RISC/2, 10 N/A, 11 WB=RISC/4

input   [ppic_ints-1:0]  pic_ints_i;

//

// Instruction WISHBONE interface

//

input                   iwb_clk_i;      // clock input

input                   iwb_rst_i;      // reset input

input                   iwb_ack_i;      // normal termination

input                   iwb_err_i;      // termination w/ error

input                   iwb_rty_i;      // termination w/ retry

input   [dw-1:0] iwb_dat_i;      // input data bus

output                  iwb_cyc_o;      // cycle valid output

output  [aw-1:0] iwb_adr_o;      // address bus outputs

output                  iwb_stb_o;      // strobe output

output                  iwb_we_o;       // indicates write transfer

output  [3:0]            iwb_sel_o;      // byte select outputs

output  [dw-1:0] iwb_dat_o;      // output data bus

`ifdef OR1200_WB_CAB

output                  iwb_cab_o;      // indicates consecutive address burst

`endif

`ifdef OR1200_WB_B3

output  [2:0]            iwb_cti_o;      // cycle type identifier

output  [1:0]            iwb_bte_o;      // burst type extension

`endif

//

// Data WISHBONE interface

//

input                   dwb_clk_i;      // clock input

input                   dwb_rst_i;      // reset input

input                   dwb_ack_i;      // normal termination

input                   dwb_err_i;      // termination w/ error

input                   dwb_rty_i;      // termination w/ retry

input   [dw-1:0] dwb_dat_i;      // input data bus

output                  dwb_cyc_o;      // cycle valid output

output  [aw-1:0] dwb_adr_o;      // address bus outputs

output                  dwb_stb_o;      // strobe output

output                  dwb_we_o;       // indicates write transfer

output  [3:0]            dwb_sel_o;      // byte select outputs

output  [dw-1:0] dwb_dat_o;      // output data bus

`ifdef OR1200_WB_CAB

output                  dwb_cab_o;      // indicates consecutive address burst

`endif

`ifdef OR1200_WB_B3

output  [2:0]            dwb_cti_o;      // cycle type identifier

output  [1:0]            dwb_bte_o;      // burst type extension

`endif

//

// External Debug Interface

//

input                   dbg_stall_i;    // External Stall Input

input                   dbg_ewt_i;      // External Watchpoint Trigger Input

output  [3:0]            dbg_lss_o;      // External Load/Store Unit Status

output  [1:0]            dbg_is_o;       // External Insn Fetch Status

output  [10:0]           dbg_wp_o;       // Watchpoints Outputs

output                  dbg_bp_o;       // Breakpoint Output

input                   dbg_stb_i;      // External Address/Data Strobe

input                   dbg_we_i;       // External Write Enable

input   [aw-1:0] dbg_adr_i;      // External Address Input

input   [dw-1:0] dbg_dat_i;      // External Data Input

output  [dw-1:0] dbg_dat_o;      // External Data Output

output                  dbg_ack_o;      // External Data Acknowledge (not WB compatible)

`ifdef OR1200_BIST

//

// RAM BIST

//

input mbist_si_i;

input [`OR1200_MBIST_CTRL_WIDTH - 1:0] mbist_ctrl_i;

output mbist_so_o;

`endif

//

// Power Management

//

input                   pm_cpustall_i;

output  [3:0]            pm_clksd_o;

output                  pm_dc_gate_o;

output                  pm_ic_gate_o;

output                  pm_dmmu_gate_o;

output                  pm_immu_gate_o;

output                  pm_tt_gate_o;

output                  pm_cpu_gate_o;

output                  pm_wakeup_o;

output                  pm_lvolt_o;

//

// Internal wires and regs

//

//

// DC to SB

//

wire    [dw-1:0] dcsb_dat_dc;

wire    [aw-1:0] dcsb_adr_dc;

wire                    dcsb_cyc_dc;

wire                    dcsb_stb_dc;

wire                    dcsb_we_dc;

wire    [3:0]            dcsb_sel_dc;

wire                    dcsb_cab_dc;

wire    [dw-1:0] dcsb_dat_sb;

wire                    dcsb_ack_sb;

wire                    dcsb_err_sb;

//

// SB to BIU

//

wire    [dw-1:0] sbbiu_dat_sb;

wire    [aw-1:0] sbbiu_adr_sb;

wire                    sbbiu_cyc_sb;

wire                    sbbiu_stb_sb;

wire                    sbbiu_we_sb;

wire    [3:0]            sbbiu_sel_sb;

wire                    sbbiu_cab_sb;

wire    [dw-1:0] sbbiu_dat_biu;

wire                    sbbiu_ack_biu;

wire                    sbbiu_err_biu;

//

// IC to BIU

//

wire    [dw-1:0] icbiu_dat_ic;

wire    [aw-1:0] icbiu_adr_ic;

wire    [aw-1:0] icbiu_adr_ic_word;

wire                    icbiu_cyc_ic;

wire                    icbiu_stb_ic;

wire                    icbiu_we_ic;

wire    [3:0]            icbiu_sel_ic;

wire    [3:0]            icbiu_tag_ic;

wire                    icbiu_cab_ic;

wire    [dw-1:0] icbiu_dat_biu;

wire                    icbiu_ack_biu;

wire                    icbiu_err_biu;

wire    [3:0]            icbiu_tag_biu;

//

// SR Interface (this signal can be connected to the input pin)

//

wire                    boot_adr_sel = `OR1200_SR_EPH_DEF;

//

// CPU's SPR access to various RISC units (shared wires)

//

wire                    supv;

wire    [aw-1:0] spr_addr;

wire    [dw-1:0] spr_dat_cpu;

wire    [31:0]           spr_cs;

wire                    spr_we;

//

// SB

//

wire                    sb_en;

//

// DMMU and CPU

//

wire                    dmmu_en;

wire    [31:0]           spr_dat_dmmu;

//

// DMMU and QMEM

//

wire                    qmemdmmu_err_qmem;

wire    [3:0]            qmemdmmu_tag_qmem;

wire    [aw-1:0] qmemdmmu_adr_dmmu;

wire                    qmemdmmu_cycstb_dmmu;

wire                    qmemdmmu_ci_dmmu;

//

// CPU and data memory subsystem

//

wire                    dc_en;

wire    [31:0]           dcpu_adr_cpu;

wire                    dcpu_cycstb_cpu;

wire                    dcpu_we_cpu;

wire    [3:0]            dcpu_sel_cpu;

wire    [3:0]            dcpu_tag_cpu;

wire    [31:0]           dcpu_dat_cpu;

wire    [31:0]           dcpu_dat_qmem;

wire                    dcpu_ack_qmem;

wire                    dcpu_rty_qmem;

wire                    dcpu_err_dmmu;

wire    [3:0]            dcpu_tag_dmmu;

wire                    dc_no_writethrough;

//

// IMMU and CPU

//

wire                    immu_en;

wire    [31:0]           spr_dat_immu;

//

// CPU and insn memory subsystem

//

wire                    ic_en;

wire    [31:0]           icpu_adr_cpu;

wire                    icpu_cycstb_cpu;

wire    [3:0]            icpu_sel_cpu;

wire    [3:0]            icpu_tag_cpu;

wire    [31:0]           icpu_dat_qmem;

wire                    icpu_ack_qmem;

wire    [31:0]           icpu_adr_immu;

wire                    icpu_err_immu;

wire    [3:0]            icpu_tag_immu;

wire                    icpu_rty_immu;

//

// IMMU and QMEM

//

wire    [aw-1:0] qmemimmu_adr_immu;

wire                    qmemimmu_rty_qmem;

wire                    qmemimmu_err_qmem;

wire    [3:0]            qmemimmu_tag_qmem;

wire                    qmemimmu_cycstb_immu;

wire                    qmemimmu_ci_immu;

//

// QMEM and IC

//

wire    [aw-1:0] icqmem_adr_qmem;

wire                    icqmem_rty_ic;

wire                    icqmem_err_ic;

wire    [3:0]            icqmem_tag_ic;

wire                    icqmem_cycstb_qmem;

wire                    icqmem_ci_qmem;

wire    [31:0]           icqmem_dat_ic;

wire                    icqmem_ack_ic;

//

// QMEM and DC

//

wire    [aw-1:0] dcqmem_adr_qmem;

wire                    dcqmem_rty_dc;

wire                    dcqmem_err_dc;

wire    [3:0]            dcqmem_tag_dc;

wire                    dcqmem_cycstb_qmem;

wire                    dcqmem_ci_qmem;

wire    [31:0]           dcqmem_dat_dc;

wire    [31:0]           dcqmem_dat_qmem;

wire                    dcqmem_we_qmem;

wire    [3:0]            dcqmem_sel_qmem;

wire                    dcqmem_ack_dc;

//

// Connection between CPU and PIC

//

wire    [dw-1:0] spr_dat_pic;

wire                    pic_wakeup;

wire                    sig_int;

//

// Connection between CPU and PM

//

wire    [dw-1:0] spr_dat_pm;

//

// CPU and TT

//

wire    [dw-1:0] spr_dat_tt;

output wire                     sig_tick; // jb

//

// Debug port and caches/MMUs

//

wire    [dw-1:0] spr_dat_du;

wire                    du_stall;

wire    [dw-1:0] du_addr;

wire    [dw-1:0] du_dat_du;

wire                    du_read;

wire                    du_write;

wire    [13:0]           du_except_trig;

wire    [13:0]           du_except_stop;

wire    [`OR1200_DU_DSR_WIDTH-1:0]     du_dsr;

wire    [24:0]           du_dmr1;

wire    [dw-1:0] du_dat_cpu;

wire    [dw-1:0] du_lsu_store_dat;

wire    [dw-1:0] du_lsu_load_dat;

wire                    du_hwbkpt;

wire                    du_hwbkpt_ls_r = 1'b0;

wire                    flushpipe;

wire                    ex_freeze;

wire                    wb_freeze;

wire                    id_void;

wire                    ex_void;

wire    [31:0]           id_insn;

wire    [31:0]           ex_insn;

wire    [31:0]           wb_insn;

wire    [31:0]           id_pc;

wire    [31:0]           ex_pc;

wire    [31:0]           wb_pc;

wire    [`OR1200_BRANCHOP_WIDTH-1:0]     branch_op;

wire    [31:0]           spr_dat_npc;

wire    [31:0]           rf_dataw;

wire                    abort_ex;

wire                    abort_mvspr;

`ifdef OR1200_BIST

//

// RAM BIST

//

wire                    mbist_immu_so;

wire                    mbist_ic_so;

wire                    mbist_dmmu_so;

wire                    mbist_dc_so;

wire                    mbist_qmem_so;

wire                    mbist_immu_si = mbist_si_i;

wire                    mbist_ic_si = mbist_immu_so;

wire                    mbist_qmem_si = mbist_ic_so;

wire                    mbist_dmmu_si = mbist_qmem_so;

wire                    mbist_dc_si = mbist_dmmu_so;

assign                  mbist_so_o = mbist_dc_so;

`endif

wire  [3:0] icqmem_sel_qmem;

wire  [3:0] icqmem_tag_qmem;

wire  [3:0] dcqmem_tag_qmem;

//

// Instantiation of Instruction WISHBONE BIU

//

or1200_wb_biu iwb_biu(

        // RISC clk, rst and clock control

        .clk(clk_i),

        .rst(rst_i),

        .clmode(clmode_i),

        // WISHBONE interface

        .wb_clk_i(iwb_clk_i),

        .wb_rst_i(iwb_rst_i),

        .wb_ack_i(iwb_ack_i),

        .wb_err_i(iwb_err_i),

        .wb_rty_i(iwb_rty_i),

        .wb_dat_i(iwb_dat_i),

        .wb_cyc_o(iwb_cyc_o),

        .wb_adr_o(iwb_adr_o),

        .wb_stb_o(iwb_stb_o),

        .wb_we_o(iwb_we_o),

        .wb_sel_o(iwb_sel_o),

        .wb_dat_o(iwb_dat_o),

`ifdef OR1200_WB_CAB

        .wb_cab_o(iwb_cab_o),

`endif

`ifdef OR1200_WB_B3

        .wb_cti_o(iwb_cti_o),

        .wb_bte_o(iwb_bte_o),

`endif

        // Internal RISC bus

        .biu_dat_i(icbiu_dat_ic),

        .biu_adr_i(icbiu_adr_ic_word),

        .biu_cyc_i(icbiu_cyc_ic),

        .biu_stb_i(icbiu_stb_ic),

        .biu_we_i(icbiu_we_ic),

        .biu_sel_i(icbiu_sel_ic),

        .biu_cab_i(icbiu_cab_ic),

        .biu_dat_o(icbiu_dat_biu),

        .biu_ack_o(icbiu_ack_biu),

        .biu_err_o(icbiu_err_biu)

);

assign icbiu_adr_ic_word = {icbiu_adr_ic[31:2], 2'h0};

//

// Instantiation of Data WISHBONE BIU

//

or1200_wb_biu dwb_biu(

        // RISC clk, rst and clock control

        .clk(clk_i),

        .rst(rst_i),

        .clmode(clmode_i),

        // WISHBONE interface

        .wb_clk_i(dwb_clk_i),

        .wb_rst_i(dwb_rst_i),

        .wb_ack_i(dwb_ack_i),

        .wb_err_i(dwb_err_i),

        .wb_rty_i(dwb_rty_i),

        .wb_dat_i(dwb_dat_i),

        .wb_cyc_o(dwb_cyc_o),

        .wb_adr_o(dwb_adr_o),

        .wb_stb_o(dwb_stb_o),

        .wb_we_o(dwb_we_o),

        .wb_sel_o(dwb_sel_o),

        .wb_dat_o(dwb_dat_o),

`ifdef OR1200_WB_CAB

        .wb_cab_o(dwb_cab_o),

`endif

`ifdef OR1200_WB_B3

        .wb_cti_o(dwb_cti_o),

        .wb_bte_o(dwb_bte_o),

`endif

        // Internal RISC bus

        .biu_dat_i(sbbiu_dat_sb),

        .biu_adr_i(sbbiu_adr_sb),

        .biu_cyc_i(sbbiu_cyc_sb),

        .biu_stb_i(sbbiu_stb_sb),

        .biu_we_i(sbbiu_we_sb),

        .biu_sel_i(sbbiu_sel_sb),

        .biu_cab_i(sbbiu_cab_sb),

        .biu_dat_o(sbbiu_dat_biu),

        .biu_ack_o(sbbiu_ack_biu),

        .biu_err_o(sbbiu_err_biu)

);

//

// Instantiation of IMMU

//

or1200_immu_top or1200_immu_top(

        // Rst and clk

        .clk(clk_i),

        .rst(rst_i),

`ifdef OR1200_BIST

        // RAM BIST

        .mbist_si_i(mbist_immu_si),

        .mbist_so_o(mbist_immu_so),

        .mbist_ctrl_i(mbist_ctrl_i),

`endif

        // CPU and IMMU

        .ic_en(ic_en),

        .immu_en(immu_en),

        .supv(supv),

        .icpu_adr_i(icpu_adr_cpu),

        .icpu_cycstb_i(icpu_cycstb_cpu),

        .icpu_adr_o(icpu_adr_immu),

        .icpu_tag_o(icpu_tag_immu),

        .icpu_rty_o(icpu_rty_immu),

        .icpu_err_o(icpu_err_immu),

        // SR Interface

        .boot_adr_sel_i(boot_adr_sel),

        // SPR access

        .spr_cs(spr_cs[`OR1200_SPR_GROUP_IMMU]),

        .spr_write(spr_we),

        .spr_addr(spr_addr),

        .spr_dat_i(spr_dat_cpu),

        .spr_dat_o(spr_dat_immu),

        // QMEM and IMMU

        .qmemimmu_rty_i(qmemimmu_rty_qmem),

        .qmemimmu_err_i(qmemimmu_err_qmem),

        .qmemimmu_tag_i(qmemimmu_tag_qmem),

        .qmemimmu_adr_o(qmemimmu_adr_immu),

        .qmemimmu_cycstb_o(qmemimmu_cycstb_immu),

        .qmemimmu_ci_o(qmemimmu_ci_immu)

);

//

// Instantiation of Instruction Cache

//

or1200_ic_top or1200_ic_top(

        .clk(clk_i),

        .rst(rst_i),

`ifdef OR1200_BIST

        // RAM BIST

        .mbist_si_i(mbist_ic_si),

        .mbist_so_o(mbist_ic_so),

        .mbist_ctrl_i(mbist_ctrl_i),

`endif

        // IC and QMEM

        .ic_en(ic_en),

        .icqmem_adr_i(icqmem_adr_qmem),

        .icqmem_cycstb_i(icqmem_cycstb_qmem),

        .icqmem_ci_i(icqmem_ci_qmem),

        .icqmem_sel_i(icqmem_sel_qmem),

        .icqmem_tag_i(icqmem_tag_qmem),

        .icqmem_dat_o(icqmem_dat_ic),

        .icqmem_ack_o(icqmem_ack_ic),

        .icqmem_rty_o(icqmem_rty_ic),

        .icqmem_err_o(icqmem_err_ic),

        .icqmem_tag_o(icqmem_tag_ic),

        // SPR access

        .spr_cs(spr_cs[`OR1200_SPR_GROUP_IC]),

        .spr_write(spr_we),

        .spr_dat_i(spr_dat_cpu),

        // IC and BIU

        .icbiu_dat_o(icbiu_dat_ic),

        .icbiu_adr_o(icbiu_adr_ic),

        .icbiu_cyc_o(icbiu_cyc_ic),

        .icbiu_stb_o(icbiu_stb_ic),

        .icbiu_we_o(icbiu_we_ic),

        .icbiu_sel_o(icbiu_sel_ic),

        .icbiu_cab_o(icbiu_cab_ic),

        .icbiu_dat_i(icbiu_dat_biu),

        .icbiu_ack_i(icbiu_ack_biu),

        .icbiu_err_i(icbiu_err_biu)

);

//

// Instantiation of Instruction Cache

//

or1200_cpu or1200_cpu(

        .clk(clk_i),

        .rst(rst_i),

        // Connection QMEM and IFETCHER inside CPU

        .ic_en(ic_en),

        .icpu_adr_o(icpu_adr_cpu),

        .icpu_cycstb_o(icpu_cycstb_cpu),

        .icpu_sel_o(icpu_sel_cpu),

        .icpu_tag_o(icpu_tag_cpu),

        .icpu_dat_i(icpu_dat_qmem),

        .icpu_ack_i(icpu_ack_qmem),

        .icpu_rty_i(icpu_rty_immu),

        .icpu_adr_i(icpu_adr_immu),

        .icpu_err_i(icpu_err_immu),

        .icpu_tag_i(icpu_tag_immu),

        // Connection CPU to external Debug port

        .id_void(id_void),

        .id_insn(id_insn),

        .ex_void(ex_void),

        .ex_insn(ex_insn),

        .ex_freeze(ex_freeze),

        .wb_insn(wb_insn),

        .wb_freeze(wb_freeze),

        .id_pc(id_pc),

        .ex_pc(ex_pc),

        .wb_pc(wb_pc),

        .branch_op(branch_op),

        .rf_dataw(rf_dataw),

        .ex_flushpipe(flushpipe),

        .du_stall(du_stall),

        .du_addr(du_addr),

        .du_dat_du(du_dat_du),

        .du_read(du_read),

        .du_write(du_write),

        .du_except_trig(du_except_trig),

        .du_except_stop(du_except_stop),

        .du_dsr(du_dsr),

        .du_dmr1(du_dmr1),

        .du_hwbkpt(du_hwbkpt),

        .du_hwbkpt_ls_r(du_hwbkpt_ls_r),

        .du_dat_cpu(du_dat_cpu),

        .du_lsu_store_dat(du_lsu_store_dat),

        .du_lsu_load_dat(du_lsu_load_dat),

        .abort_mvspr(abort_mvspr),

        .abort_ex(abort_ex),

        // Connection IMMU and CPU internally

        .immu_en(immu_en),

        // Connection QMEM and CPU

        .dc_en(dc_en),

        .dcpu_adr_o(dcpu_adr_cpu),

        .dcpu_cycstb_o(dcpu_cycstb_cpu),

        .dcpu_we_o(dcpu_we_cpu),

        .dcpu_sel_o(dcpu_sel_cpu),

        .dcpu_tag_o(dcpu_tag_cpu),

        .dcpu_dat_o(dcpu_dat_cpu),

        .dcpu_dat_i(dcpu_dat_qmem),

        .dcpu_ack_i(dcpu_ack_qmem),

        .dcpu_rty_i(dcpu_rty_qmem),

        .dcpu_err_i(dcpu_err_dmmu),

        .dcpu_tag_i(dcpu_tag_dmmu),

        .dc_no_writethrough(dc_no_writethrough),

        // Connection DMMU and CPU internally