up_axi 一个将axi_lite接口转换成寄存器接口的模块

本文介绍了一个由ADI提供的AXI4到P-Core的桥接模块,该模块包含防止死机的机制和严谨的握手信号处理,确保了在8个周期内未完成操作时能够响应ACK总线,并在master端撤销写请求时释放写通道。

摘要生成于 C知道 ,由 DeepSeek-R1 满血版支持, 前往体验 >

 

这是ADI提供的小模块。

1,加入了防止死机的判断,8个周期后没有完成操作自动相应ack总线。

2,会一直保持up_wreq,直到master端撤销写请求。这就需要检测第一个up_wreq的跳变作为实际的写,或者有严谨的握手信号处理。

 


`timescale 1ns/100ps

module up_axi (

  // reset and clocks

  up_rstn,
  up_clk,

  // axi4 interface

  up_axi_awvalid,
  up_axi_awaddr,
  up_axi_awready,
  up_axi_wvalid,
  up_axi_wdata,
  up_axi_wstrb,
  up_axi_wready,
  up_axi_bvalid,
  up_axi_bresp,
  up_axi_bready,
  up_axi_arvalid,
  up_axi_araddr,
  up_axi_arready,
  up_axi_rvalid,
  up_axi_rresp,
  up_axi_rdata,
  up_axi_rready,

  // pcore interface

  up_wreq,
  up_waddr,
  up_wdata,
  up_wack,
  
  up_rreq,
  up_raddr,
  up_rdata,
  up_rack
  
  );

  // parameters

  parameter   ADDRESS_WIDTH = 14;
  localparam  AW = ADDRESS_WIDTH - 1;

  // reset and clocks

  input           up_rstn;
  input           up_clk;

  // axi4 interface

  input           up_axi_awvalid;
  input   [31:0]  up_axi_awaddr;
  output          up_axi_awready;
  input           up_axi_wvalid;
  input   [31:0]  up_axi_wdata;
  input   [ 3:0]  up_axi_wstrb;
  output          up_axi_wready;
  output          up_axi_bvalid;
  output  [ 1:0]  up_axi_bresp;
  input           up_axi_bready;
  input           up_axi_arvalid;
  input   [31:0]  up_axi_araddr;
  output          up_axi_arready;
  output          up_axi_rvalid;
  output  [ 1:0]  up_axi_rresp;
  output  [31:0]  up_axi_rdata;
  input           up_axi_rready;

  // pcore interface

  output          up_wreq;
  output  [AW:0]  up_waddr;
  output  [31:0]  up_wdata;
  input           up_wack;
  output          up_rreq;
  output  [AW:0]  up_raddr;
  input   [31:0]  up_rdata;
  input           up_rack;

  // internal registers

  reg             up_axi_awready = 'd0;
  reg             up_axi_wready = 'd0;
  reg             up_axi_bvalid = 'd0;
  reg             up_wsel = 'd0;
  reg             up_wreq = 'd0;
  reg     [AW:0]  up_waddr = 'd0;
  reg     [31:0]  up_wdata = 'd0;
  reg     [ 2:0]  up_wcount = 'd0;
  reg             up_wack_int = 'd0;
  reg             up_wack_int_d = 'd0;
  reg             up_axi_arready = 'd0;
  reg             up_axi_rvalid = 'd0;
  reg     [31:0]  up_axi_rdata = 'd0;
  reg             up_rsel = 'd0;
  reg             up_rreq = 'd0;
  reg     [AW:0]  up_raddr = 'd0;
  reg     [ 3:0]  up_rcount = 'd0;
  reg             up_rack_int = 'd0;
  reg     [31:0]  up_rdata_int = 'd0;
  reg             up_rack_int_d = 'd0;
  reg     [31:0]  up_rdata_int_d = 'd0;

  // write channel interface
 
  assign up_axi_bresp = 2'd0;

  always @(negedge up_rstn or posedge up_clk) begin
    if (up_rstn == 1'b0) begin
      up_axi_awready <= 'd0;
      up_axi_wready <= 'd0;
      up_axi_bvalid <= 'd0;
    end else begin
      if (up_axi_awready == 1'b1) begin
        up_axi_awready <= 1'b0;
      end else if (up_wack_int == 1'b1) begin
        up_axi_awready <= 1'b1;
      end
      if (up_axi_wready == 1'b1) begin
        up_axi_wready <= 1'b0;
      end else if (up_wack_int == 1'b1) begin
        up_axi_wready <= 1'b1;
      end
      if ((up_axi_bready == 1'b1) && (up_axi_bvalid == 1'b1)) begin
        up_axi_bvalid <= 1'b0;
      end else if (up_wack_int_d == 1'b1) begin
        up_axi_bvalid <= 1'b1;
      end
    end
  end       

  always @(negedge up_rstn or posedge up_clk) begin
    if (up_rstn == 1'b0) begin
      up_wsel <= 'd0;
      up_wreq <= 'd0;
      up_waddr <= 'd0;
      up_wdata <= 'd0;
      up_wcount <= 'd0;
    end else begin
      if (up_wsel == 1'b1) begin
        if ((up_axi_bready == 1'b1) && (up_axi_bvalid == 1'b1)) begin up_wsel <= 1'b0; end
        up_wreq <= 1'b0;
        up_waddr <= up_waddr;
        up_wdata <= up_wdata;
        up_wcount <= up_wcount + 1'b1;
      end else begin
        up_wsel <= up_axi_awvalid & up_axi_wvalid;
        up_wreq <= up_axi_awvalid & up_axi_wvalid;
        up_waddr <= up_axi_awaddr[AW+2:2];
        up_wdata <= up_axi_wdata;
        up_wcount <= 3'd0;
      end
    end
  end

  always @(negedge up_rstn or posedge up_clk) begin
    if (up_rstn == 0) begin
      up_wack_int <= 'd0;
      up_wack_int_d <= 'd0;
    end else begin
      if ((up_wcount == 3'h7) && (up_wack == 1'b0)) begin
        up_wack_int <= 1'b1;
      end else if (up_wsel == 1'b1) begin
        up_wack_int <= up_wack;
      end
      up_wack_int_d <= up_wack_int;
    end
  end

  // read channel interface

  assign up_axi_rresp = 2'd0;

  always @(negedge up_rstn or posedge up_clk) begin
    if (up_rstn == 1'b0) begin
      up_axi_arready <= 'd0;
      up_axi_rvalid <= 'd0;
      up_axi_rdata <= 'd0;
    end else begin
      if (up_axi_arready == 1'b1) begin
        up_axi_arready <= 1'b0;
      end else if (up_rack_int == 1'b1) begin
        up_axi_arready <= 1'b1;
      end
      if ((up_axi_rready == 1'b1) && (up_axi_rvalid == 1'b1)) begin
        up_axi_rvalid <= 1'b0;
        up_axi_rdata <= 32'd0;
      end else if (up_rack_int_d == 1'b1) begin
        up_axi_rvalid <= 1'b1;
        up_axi_rdata <= up_rdata_int_d;
      end
    end
  end       

  always @(negedge up_rstn or posedge up_clk) begin
    if (up_rstn == 1'b0) begin
      up_rsel <= 'd0;
      up_rreq <= 'd0;
      up_raddr <= 'd0;
      up_rcount <= 'd0;
    end else begin
      if (up_rsel == 1'b1) begin
        if ((up_axi_rready == 1'b1) && (up_axi_rvalid == 1'b1)) begin
          up_rsel <= 1'b0;
        end
        up_rreq <= 1'b0;
        up_raddr <= up_raddr;
      end else begin
        up_rsel <= up_axi_arvalid;
        up_rreq <= up_axi_arvalid;
        up_raddr <= up_axi_araddr[AW+2:2];
      end
      if (up_rack_int == 1'b1) begin
        up_rcount <= 4'd0;
      end else if (up_rcount[3] == 1'b1) begin
        up_rcount <= up_rcount + 1'b1;
      end else if (up_rreq == 1'b1) begin
        up_rcount <= 4'd8;
      end
    end
  end

  always @(negedge up_rstn or posedge up_clk) begin
    if (up_rstn == 0) begin
      up_rack_int <= 'd0;
      up_rdata_int <= 'd0;
      up_rack_int_d <= 'd0;
      up_rdata_int_d <= 'd0;
    end else begin
      if ((up_rcount == 4'hf) && (up_rack == 1'b0)) begin
        up_rack_int <= 1'b1;
        up_rdata_int <= {2{16'hdead}};
      end else begin
        up_rack_int <= up_rack;
        up_rdata_int <= up_rdata;
      end
      up_rack_int_d <= up_rack_int;
      up_rdata_int_d <= up_rdata_int;
    end
  end

endmodule

// ***************************************************************************
// ***************************************************************************
<think>好的,用户之前询问了Vivado中MIG IP核的作用,现在他们又问到了M_AXI_LITE接口的作用。我需要先确认这两个问题之间的关联,可能用户正在使用Xilinx FPGA进行设计,涉及到了AXI接口的相关知识。 首先,M_AXI_LITEAXI4-Lite接口的主设备端,常用于低带宽的配置和控制。用户可能在项目中需要连接一些需要配置的IP核,比如DMA、定时器或者其他外设,这时候AXI-Lite接口就派上用场了。 接下来,我需要回忆AXI4协议的不同类型。AXI4有三种:AXI4、AXI4-LiteAXI4-Stream。AXI4-Lite是简化版,用于简单的寄存器访问,不支持突发传输,适合配置寄存器。而M_AXI_LITE中的“M”代表Master,主设备,负责发起读写请求。 用户可能想知道这个接口的具体应用场景,比如在Zynq SoC中,PS和PL之间的通信,或者FPGA内部不同IP核之间的控制信号传递。需要举一些例子,比如通过AXI-Lite配置一个GPIO模块的寄存器,或者读取状态寄存器的值。 另外,用户可能对接口的信号线感兴趣,比如地址、数据、读写控制信号等。需要简要描述这些信号的作用,但不需要太深入,保持易懂。 还要注意和之前MIG IP核的回答结构类似,分点说明,保持结构清晰。可能需要分点讲作用、特点、应用场景、优势等。 需要确保术语正确,比如AXI-Lite的特性,如不支持突发,每次传输一个数据,32位或64位地址和数据宽度等。同时要强调其低功耗和简化设计的好处。 用户可能有更深层的需求,比如在设计中如何正确使用这个接口,或者遇到相关问题时如何调试。但当前问题只需要介绍作用,所以可以提到它简化设计,但不需要展开调试方法。 最后,检查是否有需要补充的地方,比如与AXI4-Full的区别,或者在实际工程中的典型用例,如MicroBlaze处理器通过AXI-Lite控制外设。确保回答准确、易懂,符合用户的知识水平。</think>在FPGA或SoC设计中,**M_AXI_LITE接口**是一种基于AXI4-Lite协议的主设备接口(Master Interface),主要用于**低带宽、低复杂度的寄存器配置和状态读取**。以下是其核心作用的分步说明: --- ### 1. **核心功能定位** - **简化控制通路**:专为寄存器级访问设计,适合传输少量控制命令或状态信息(如使能信号、中断标志)。 - **典型场景**: - 配置外设IP核(如DMA、定时器、ADC驱动) - 读取传感器状态(如温度值$25.5^\circ\text{C}$) - 与处理器(如ARM Cortex-A9 in Zynq)进行低速通信 --- ### 2. **协议特性** - **AXI4-Lite子集**: - **单次传输**:不支持突发(Burst)操作,每次读写仅传输1个数据(如32位数据$0x12345678$)。 - **地址范围小**:通常寻址范围不超过32位(4GB空间),实际应用常映射到局部寄存器(如$0x4000\_0000$到$0x4000\_FFFF$)。 - **信号精简**:相比AXI4-Full,信号线减少约70%,仅包含: ```verilog AWADDR/WDATA/WVALID → 写地址、数据、有效信号 ARADDR/RDATA/RVALID → 读地址、数据、有效信号 BVALID → 写响应完成 ``` --- ### 3. **典型应用架构** - **SoC控制中枢**(如Xilinx Zynq): ```plaintext [ARM Cortex-A9] --M_AXI_LITE--> [FPGA逻辑IP核(如PWM、SPI)] ↳ 配置IP寄存器/读取状态 ``` - **FPGA内部管理**: ```plaintext [MicroBlaze软核] --M_AXI_LITE--> [自定义逻辑模块] ↳ 设置工作模式/读取错误计数器 ``` --- ### 4. **设计优势** - **资源节省**: - 逻辑资源消耗比AXI4-Full减少约50%(无突发控制逻辑) - 适合低功耗场景(如IoT设备) - **易用性**: - Vivado IP Integrator可自动生成接口适配逻辑 - 与Xilinx SDK/C语言驱动程序天然兼容(通过`xil_io.h`库函数) --- ### 5. **与AXI4-Full接口对比** | 特性 | M_AXI_LITE | M_AXIAXI4-Full) | |--------------------|---------------------|---------------------| | 突发传输 | ❌ 不支持 | ✅ 支持(最大256拍)| | 数据位宽 | 通常32/64位 | 可扩展至1024位 | | 适用场景 | 控制/状态寄存器 | 高速数据传输(如DDR)| | 延迟敏感性 | 容忍较高延迟 | 需严格时序优化 | --- ### 实际案例 - **PWM调光控制**: - 通过M_AXI_LITE设置占空比(如写入$0x3FF$对应100%亮度) - 读取过温报警标志(`0x1`表示温度超限) - **以太网MAC配置**: - 设置MAC地址(如`0x001B638A12C3`) - 查询链路状态(`0x0`表示断开) 通过M_AXI_LITE接口,开发者能以最小资源开销实现可靠的配置通信,特别适合控制密集型但数据量小的系统设计。
评论 3
添加红包

请填写红包祝福语或标题

红包个数最小为10个

红包金额最低5元

当前余额3.43前往充值 >
需支付:10.00
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明:

1.余额是钱包充值的虚拟货币,按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载,可以购买VIP、付费专栏及课程。

余额充值