Linux内核4.14版本——DMA Engine框架分析(6)-实战(测试dma驱动)
作者:互联网
1. dw-axi-dmac驱动
dw-axi-dmac驱动4.14版本没有,是从5.4版本移植的,基本没有修改,这里不做介绍。linux-5.4\drivers\dma\dw-axi-dmac\dw-axi-dmac-platform.c
2. dma的测试程序
2.1 内核程序
以模块.ko的模式加载如内核
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/miscdevice.h>
#include <linux/fs.h>
#include <linux/init.h>
#include <asm/uaccess.h>
#include <linux/dmaengine.h>
#include <linux/uaccess.h> /* For copy_to_user/put_user/... */
#include <linux/dma-mapping.h>
#define DRIVER_NAME "axidma"
#define AXIDMA_IOC_MAGIC 'A'
#define AXIDMA_IOCGETCHN _IO(AXIDMA_IOC_MAGIC, 0)
#define AXIDMA_IOCCFGANDSTART _IO(AXIDMA_IOC_MAGIC, 1)
#define AXIDMA_IOCGETSTATUS _IO(AXIDMA_IOC_MAGIC, 2)
#define AXIDMA_IOCRELEASECHN _IO(AXIDMA_IOC_MAGIC, 3)
struct dma_chan *dmaTest_chan = NULL;
static int dmaTest_Flag = -1;
#define DMA_STATUS_UNFINISHED 0
#define DMA_STATUS_FINISHED 1
static void *src11;
static u64 src_phys;
#define BUF_SIZE (512)
static void *dst11;
static u64 dst_phys;
static int axidma_open(struct inode *inode, struct file *file)
{
printk("Open: do nothing\n");
return 0;
}
static int axidma_release(struct inode *inode, struct file *file)
{
printk("Release: do nothing\n");
return 0;
}
static ssize_t axidma_write(struct file *file, const char __user *data, size_t len, loff_t *ppos)
{
printk("Write: do nothing\n");
return 0;
}
static void dma_complete_func(void *status)
{
printk("dma_complete_func dma_complete!\n");
}
static long axidma_unlocked_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{
struct dma_device *dma_dev;
struct dma_async_tx_descriptor *tx = NULL;
dma_cap_mask_t mask;
dma_cookie_t cookie;
enum dma_ctrl_flags flags;
unsigned char *su1, *su2;
unsigned char count;
switch(cmd)
{
case AXIDMA_IOCGETCHN:
{
dma_cap_zero(mask);
dma_cap_set(DMA_MEMCPY, mask);
dmaTest_chan = dma_request_channel(mask, NULL, NULL);
if(!dmaTest_chan){
printk("dma request channel failed\n");
goto error;
}
printk("dmaTest_chan = %d\n",dmaTest_chan->chan_id);
break;
}
case AXIDMA_IOCCFGANDSTART:
{
dma_dev = dmaTest_chan->device;
src11 = dma_alloc_wc(dma_dev->dev, BUF_SIZE, &src_phys, GFP_KERNEL);
if (NULL == src11)
{
printk("can't alloc buffer for src\n");
return -ENOMEM;
}
dst11 = dma_alloc_wc(dma_dev->dev, BUF_SIZE, &dst_phys, GFP_KERNEL);
if (NULL == dst11)
{
printk("can't alloc buffer for dst\n");
return -ENOMEM;
}
memset(src11, 0xAA, BUF_SIZE);
memset(dst11, 0x55, BUF_SIZE);
flags = DMA_CTRL_ACK | DMA_PREP_INTERRUPT;
tx = dmaengine_prep_dma_memcpy(dmaTest_chan, dst_phys, src_phys, BUF_SIZE, flags);
if(!tx){
printk("Failed to prepare DMA memcpy\n");
goto error;
}
//printk("\r\nsrc_addr = 0x%llx, dst_addr = 0x%llx, len = %d\r\n", src_phys, dst_phys, BUF_SIZE);
tx->callback = dma_complete_func;
dmaTest_Flag = DMA_STATUS_UNFINISHED;
tx->callback_param = &dmaTest_Flag;
cookie = dmaengine_submit(tx);
if(dma_submit_error(cookie)){
printk("Failed to dma tx_submit\n");
goto error;
}
dma_async_issue_pending(dmaTest_chan);
break;
}
case AXIDMA_IOCGETSTATUS:
{
if (memcmp(src11, dst11, BUF_SIZE) == 0)
{
printk("COPY OK\n");
}
else
{
printk("COPY ERROR\n");
}
for (su1 = src11, su2 = dst11, count = 0; count < 16; ++su1, ++su2, count++)
{
//printk("%x %x\n", *su1, *su2);
}
break;
}
case AXIDMA_IOCRELEASECHN:
{
dma_release_channel(dmaTest_chan);
dmaTest_Flag = DMA_STATUS_UNFINISHED;
}
break;
default:
printk("Don't support cmd [%d]\n", cmd);
break;
}
return 0;
error:
return -EFAULT;
}
/*
* Kernel Interfaces
*/
static struct file_operations axidma_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.write = axidma_write,
.unlocked_ioctl = axidma_unlocked_ioctl,
.open = axidma_open,
.release = axidma_release,
};
static struct miscdevice axidma_miscdev = {
.minor = MISC_DYNAMIC_MINOR,
.name = DRIVER_NAME,
.fops = &axidma_fops,
};
static int __init axidma_init(void)
{
int ret = 0;
ret = misc_register(&axidma_miscdev);
if(ret) {
printk (KERN_ERR "cannot register miscdev (err=%d)\n", ret);
return ret;
}
return 0;
}
static void __exit axidma_exit(void)
{
misc_deregister(&axidma_miscdev);
}
module_init(axidma_init);
module_exit(axidma_exit);
MODULE_AUTHOR("ygy");
MODULE_DESCRIPTION("Axi Dmac Driver");
MODULE_LICENSE("GPL");
2.2 用户测试程序
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/ioctl.h>
#include <fcntl.h>
#include <sys/mman.h>
#define DRIVER_NAME "/dev/axidma"
#define AXIDMA_IOC_MAGIC 'A'
#define AXIDMA_IOCGETCHN _IO(AXIDMA_IOC_MAGIC, 0)
#define AXIDMA_IOCCFGANDSTART _IO(AXIDMA_IOC_MAGIC, 1)
#define AXIDMA_IOCGETSTATUS _IO(AXIDMA_IOC_MAGIC, 2)
#define AXIDMA_IOCRELEASECHN _IO(AXIDMA_IOC_MAGIC, 3)
int main(void)
{
int fd = -1;
int ret;
/* open dev */
fd = open(DRIVER_NAME, O_RDWR);
if(fd < 0){
printf("open %s failed\n", DRIVER_NAME);
return -1;
}
/* get channel */
ret = ioctl(fd, AXIDMA_IOCGETCHN, NULL);
if(ret){
printf("ioctl: get channel failed\n");
goto error;
}
ret = ioctl(fd, AXIDMA_IOCCFGANDSTART, NULL);
if(ret){
printf("ioctl: config and start dma failed\n");
goto error;
}
/* wait finish */
while(1){
ret = ioctl(fd, AXIDMA_IOCGETSTATUS, NULL);
if(ret){
printf("ioctl: AXIDMA_IOCGETSTATUS dma failed\n");
goto error;
}
sleep(60);
}
/* release channel */
ret = ioctl(fd, AXIDMA_IOCRELEASECHN, NULL);
if(ret){
printf("ioctl: release channel failed\n");
goto error;
}
close(fd);
return 0;
error:
close(fd);
return -1;
}
标签:Engine,DMA,4.14,dma,axidma,printk,include,AXIDMA,define 来源: https://blog.csdn.net/yangguoyu8023/article/details/121991819