ap_ctrl_none协议和hls::stream的错误使用-vivado hls设计第九例

hahaha6016

837人浏览 · 2025-11-04 14:36:57

hahaha6016 · 2025-11-04 14:36:57 发布

一、关于ap_ctrl_none协议
1.将接口上的ap_start和ap_done,ap_idle,ap_ready去掉

二、使用ap_ctrl_none协议协议情况下，将接口信号使用ap_none
1.如果用户设计的顶层使用了ap_ctrl_none协议
2.并且又将接口信号使用ap_none
3.使用了ap_none的变量何时被取值是很重要的
4.顶层接口有ap_none修饰的变量，也有hls::stream变量，容易出问题
5.因为ap_none修饰的变量会造成数据的读写时机不受控制

失败案例：
顶层：
#include "top.h"

#include "hls_opencv.h"

#include "iostream"

using namespace std;

using namespace cv;

int main (int argc, char** argv)
{

IplImage* src = cvLoadImage("D:/vivado_hls/tt.jpg");
int depth = src->depth;

CvSize s;

s.width = 585*2;

s.height = 335*2;

IplImage* dst = cvCreateImage(s, 8, 3);

AXI_STREAM src_axi, dst_axi;

IplImage2AXIvideo(src, src_axi);

hls_video_scaler_top(src_axi, dst_axi, src->height, src->width,s.height,s.width);

//AXIvideo2IplImage(dst_axi, dst);

for(int i=0;i<(585*335*4);i++){
   if(!dst_axi.empty()){
       AXIvideo2IplImage(dst_axi, dst);
   }
}

cvShowImage("src",src);

cvShowImage("dst_hls",dst);

//cv::imwrite("test1.bmp",dst);

cvSaveImage("D:/output_image.jpg", dst);
cvReleaseImage(&dst); // 释放图像内存

//waitKey(0);

return 0;

}

主体设计：
#include "top.h"

void hls_video_scaler_top(AXI_STREAM& input, AXI_STREAM& output,int rows, int cols,int drows, int dcols)

{
#pragma HLS INTERFACE ap_ctrl_none port=return

#pragma HLS INTERFACE axis port=input

#pragma HLS INTERFACE axis port=output

#pragma HLS INTERFACE ap_none port=dcols

#pragma HLS INTERFACE ap_none port=drows

#pragma HLS INTERFACE ap_none port=rows

#pragma HLS INTERFACE ap_none port=cols

RGB_IMAGE img_0(rows, cols);

RGB_IMAGE img_1(drows, dcols);

#pragma HLS dataflow

hls::AXIvideo2Mat(input,img_0);

hls::Resize(img_0,img_1,HLS_INTER_LINEAR);

hls::Mat2AXIvideo(img_1, output);

}

由于上述代码使用了ap_none修饰变量：
#pragma HLS INTERFACE ap_none port=dcols

#pragma HLS INTERFACE ap_none port=drows

#pragma HLS INTERFACE ap_none port=rows

#pragma HLS INTERFACE ap_none port=cols

c/rtl仿真时候，testbench对数据流的读取，必须使用stream.empty()作为判断：
需要使用代码
for(int i=0;i<(s.width*s.high);i++){
   if(!dst_axi.empty()){
       AXIvideo2IplImage(dst_axi, dst);
   }
}
而不能使用
AXIvideo2IplImage(dst_axi, dst);
否则，rtl仿真会挂起
c/rtl仿真，会出现：WARNING: Hls::stream 'hls::stream<ap_axiu<24, 1, 1, 1> >.2' is read while empty, which may result in RTL simulation hanging.
WARNING: Hls::stream 'hls::stream<ap_axiu<24, 1, 1, 1> >.2' is read while empty, which may result in RTL simulation hanging.
WARNING: Hls::stream 'hls::stream<ap_axiu<24, 1, 1, 1> >.2' is read while empty, which may result in RTL simulation hanging.
WARNING: Hls::stream 'hls::stream<ap_axiu<24, 1, 1, 1> >.2' is read while empty, which may result in RTL simulation hanging.
WARNING: Hls::stream 'hls::stream<ap_axiu<24, 1, 1, 1> >.2' is read while empty, which may result in RTL simulation hanging.
WARNING: Hls::stream 'hls::stream<ap_axiu<24, 1, 1, 1> >.2' is read while empty, which may result in RTL simulation hanging.
WARNING: Hls::stream 'hls::stream<ap_axiu<24, 1, 1, 1> >.2' is read while empty, which may result in RTL simulation hanging.
WARNING: Hls::stream 'hls::stream<ap_axiu<24, 1, 1, 1> >.2' is read while empty, which may result in RTL simulation hanging.
WARNING: Hls::stream 'hls::stream<ap_axiu<24, 1, 1, 1> >.2' is read while empty, which may result in RTL simulation hanging
告知用户，仿真会挂起。

总结：
1.ap_none和hls::stream搭配使用的时候问题很多。
2.ap_none和hls::stream搭配使用容易造成c仿真的结果和rtl仿真的结果不一致
3.ap_ctrl_none和hls::stream搭配使用，无问题
4.ap_none信号的取值时机是靠用户和TB找准时机取值，比如ap_none的变量取值一次，hls::stream变量也是取值一次，
但是如果你ap_none取值一次，hls::stream取值row*col次，最后你发现仿真的结果是不对的。

仿真波形: