zynq-7000学习笔记(十)——Linux下通过UIO配置FAST corner寄存器

PC平台：WINDOWS 10 64位 + 虚拟机Ubuntu 14.04

Xilinx设计开发套件：Xilinx_vivado_sdk_2015.4

开发板：Zed Board

USB摄像头：罗技 C270(720P)

Linux源码：2016_R1

Linaro文件系统：linaro-vivid-developer-20150618-705.tar.gz

       在zynq平台上做开发，肯定避免不了在linux下对有AXI Lite接口的IP进行寄存器的配置，UIO是一个很方便的方法，不管你有多少个IP，都可以搞定；原理很简单，就是物理地址的映射，把IP的AXI Lite寄存器基地址映射出来，就可以对所有的寄存器进行操作了；通过HLS综合出来的IP，如果使用了AXI Lite接口，会自动生成相应的驱动代码，包括standalone和linux的驱动，直接拿来用就好了，这里说的驱动并不是指linux底层的设备驱动，而是UIO用户端的驱动；前面我已经在standalone模式下验证了FAST
corner，当时只是一张预先准备好的图片，因为环境有限，在PL端还没接摄像头，无法实时地采集到图像，而现在经过一段时间的准备，可以先在linux下就把USB摄像头采集的图像进行验证了。

一、配置linux，支持UIO



二、修改Env.txt，启动参数增加：uio_pdrv_genirq.of_id="generic-uio"

三、修改设备书，把FAST corner加上去，

hls_fast_corner {
compatible = "generic-uio";
reg = < 0x43c00000 0x10000>;
};

四、FAST corner的linux驱动代码如下，在HLS的项目目录下可以找到

// ==============================================================
// File generated by Vivado(TM) HLS - High-Level Synthesis from C, C++ and SystemC
// Version: 2015.4
// Copyright (C) 2015 Xilinx Inc. All rights reserved.
//
// ==============================================================

#ifdef __linux__

/***************************** Include Files *********************************/
#include "xhls_fast_corner.h"

/***************** Macros (Inline Functions) Definitions *********************/
#define MAX_UIO_PATH_SIZE       256
#define MAX_UIO_NAME_SIZE       64
#define MAX_UIO_MAPS            5
#define UIO_INVALID_ADDR        0

/**************************** Type Definitions ******************************/
typedef struct {
u32 addr;
u32 size;
} XHls_fast_corner_uio_map;

typedef struct {
int  uio_fd;
int  uio_num;
char name[ MAX_UIO_NAME_SIZE ];
char version[ MAX_UIO_NAME_SIZE ];
XHls_fast_corner_uio_map maps[ MAX_UIO_MAPS ];
} XHls_fast_corner_uio_info;

/***************** Variable Definitions **************************************/
static XHls_fast_corner_uio_info uio_info;

/************************** Function Implementation *************************/
static int line_from_file(char* filename, char* linebuf) {
char* s;
int i;
FILE* fp = fopen(filename, "r");
if (!fp) return -1;
s = fgets(linebuf, MAX_UIO_NAME_SIZE, fp);
fclose(fp);
if (!s) return -2;
for (i=0; (*s)&&(i<MAX_UIO_NAME_SIZE); i++) {
if (*s == '\n') *s = 0;
s++;
}
printf("linebuf:%s\n", linebuf);
return 0;
}

static int uio_info_read_name(XHls_fast_corner_uio_info* info) {
char file[ MAX_UIO_PATH_SIZE ];
sprintf(file, "/sys/class/uio/uio%d/name", info->uio_num);
return line_from_file(file, info->name);
}

static int uio_info_read_version(XHls_fast_corner_uio_info* info) {
char file[ MAX_UIO_PATH_SIZE ];
sprintf(file, "/sys/class/uio/uio%d/version", info->uio_num);
return line_from_file(file, info->version);
}

static int uio_info_read_map_addr(XHls_fast_corner_uio_info* info, int n) {
int ret;
char file[ MAX_UIO_PATH_SIZE ];
info->maps
.addr = UIO_INVALID_ADDR;
sprintf(file, "/sys/class/uio/uio%d/maps/map%d/addr", info->uio_num, n);
FILE* fp = fopen(file, "r");
if (!fp) return -1;
ret = fscanf(fp, "0x%x", &info->maps
.addr);
fclose(fp);
if (ret < 0) return -2;
return 0;
}

static int uio_info_read_map_size(XHls_fast_corner_uio_info* info, int n) {
int ret;
char file[ MAX_UIO_PATH_SIZE ];
sprintf(file, "/sys/class/uio/uio%d/maps/map%d/size", info->uio_num, n);
FILE* fp = fopen(file, "r");
if (!fp) return -1;
ret = fscanf(fp, "0x%x", &info->maps
.size);
fclose(fp);
if (ret < 0) return -2;
return 0;
}

int XHls_fast_corner_Initialize(XHls_fast_corner *InstancePtr, const char* InstanceName) {
XHls_fast_corner_uio_info *InfoPtr = &uio_info;
struct dirent **namelist;
int i, n;
char* s;
char file[ MAX_UIO_PATH_SIZE ];
char name[ MAX_UIO_NAME_SIZE ];
int flag = 0;

assert(InstancePtr != NULL);

n = scandir("/sys/class/uio", &namelist, 0, alphasort);
if (n < 0)  return XST_DEVICE_NOT_FOUND;
for (i = 0;  i < n; i++) {
strcpy(file, "/sys/class/uio/");
strcat(file, namelist[i]->d_name);
strcat(file, "/name");
if ((line_from_file(file, name) == 0) && (strcmp(name, InstanceName) == 0)) {
flag = 1;
s = namelist[i]->d_name;
s += 3; // "uio"
InfoPtr->uio_num = atoi(s);
break;
}
}
if (flag == 0)  return XST_DEVICE_NOT_FOUND;

uio_info_read_name(InfoPtr);
uio_info_read_version(InfoPtr);
for (n = 0; n < MAX_UIO_MAPS; ++n) {
uio_info_read_map_addr(InfoPtr, n);
uio_info_read_map_size(InfoPtr, n);
}

sprintf(file, "/dev/uio%d", InfoPtr->uio_num);
if ((InfoPtr->uio_fd = open(file, O_RDWR)) < 0) {
return XST_OPEN_DEVICE_FAILED;
}

// NOTE: slave interface 'Control_bus' should be mapped to uioX/map0
InstancePtr->Control_bus_BaseAddress = (u32)mmap(NULL, InfoPtr->maps[0].size, PROT_READ|PROT_WRITE, MAP_SHARED, InfoPtr->uio_fd, 0 * getpagesize());
assert(InstancePtr->Control_bus_BaseAddress);

InstancePtr->IsReady = XIL_COMPONENT_IS_READY;

return XST_SUCCESS;
}

int XHls_fast_corner_Release(XHls_fast_corner *InstancePtr) {
XHls_fast_corner_uio_info *InfoPtr = &uio_info;

assert(InstancePtr != NULL);
assert(InstancePtr->IsReady == XIL_COMPONENT_IS_READY);

munmap((void*)InstancePtr->Control_bus_BaseAddress, InfoPtr->maps[0].size);

close(InfoPtr->uio_fd);

return XST_SUCCESS;
}

#endif

五、写一个main.c调用上面的初始化函数，然后进行相应寄存器的配置

// init hls_fast_corner
if(XST_SUCCESS != XHls_sobel_Initialize(&sobel, "hls_sobel"))
{
printf("XHls_sobel_Initialize failed\n");
return 0;
}

XHls_sobel_SetRows(&sobel, IMAGE_HEIGHT);
<span style="white-space:pre">	</span>XHls_sobel_SetCols(&sobel, IMAGE_WIDTH);
<span style="white-space:pre">	</span>XHls_sobel_DisableAutoRestart(&sobel);
<span style="white-space:pre">	</span>XHls_sobel_InterruptGlobalDisable(&sobel);

我现在还没用到中断，所有先禁用掉了