rt thread lwip协议栈培训驱动结构

RT-ThreadlwIP协议栈培训驱动、协议栈结构RT-ThreadlwIP系统结构网络应用lwIP协议栈lwIP移植RT-ThreadRTOS以太网发送任务以太网接收任务网络驱动程序RT-ThreadlwIP网络驱动03_single_ethernet\drivers\fm3_emac.c03_single_ethernet\drivers\fm3_emac.h03_single_ethernet\drivers\eth_driver.c03_dual_ethernet\drivers\fm3_emac.c03_dual_ethernet\drivers\fm3_emac.h03_dual_ethernet\drivers\eth_driver.cRT-ThreadlwIP驱动结构fm3_emac_hw_initrt_device::init

openclosereadwriteeth_dstrevice::uct

netif

*netif;etheth_rx_txeth_device_init(eth_device)rt_device_registerRT-ThreadlwIP驱动结构netifnetifnetif_listtcp

threadtcpip_init_done_callbacknetif_adddhcp_startnetif_set_linkupRT-ThreadlwIP驱动结构etxtcp

threadetx

threadlink_output(netif,

p)eth_tx_thread_entryenetif->eth_tx(p);rt_sem_releaseRT-ThreadlwIP驱动结构erxEMAC

ISReth_device_readyerx

threadtcp

threadeth_rx_thread_entrynetifdevice->eth_rx(p)netif->input(p,

netif);//

tcpip_input(p,

netif);RT-ThreadlwIP驱动总结驱动结构体#define

MAX_ADDR_LEN6struct

rt_skeleton_eth{/*

inherit

from

ethernet

device

*/struct

eth_device

parent;/*

interface

address

info.

*/rt_uint8_t

dev_addr[MAX_ADDR_LEN];};static

struct

rt_skeleton_eth

_skeleton_device;RT-ThreadlwIP驱动总结设备接口static

rt_err_t

rt_skeleton_init(rt_device_t

dev){return

RT_EOK;}static

rt_err_t

rt_skeleton_open(rt_device_tdev,

rt_uint16_t

oflag){return

RT_EOK;}static

rt_err_t

rt_skeleton_close(rt_device_t

dev){return

RT_EOK;}static

rt_size_t

rt_skeleton_read(rt_device_t

dev,

rt_off_t

pos,

void*

buffer,rt_size_t

size){rt_set_errno(-RT_ENOSYS);return

0;}static

rt_size_t

rt_skeleton_write

(rt_device_t

dev,

rt_off_t

pos,

const

void*buffer,

rt_size_t

size){rt_set_errno(-RT_ENOSYS);return

0;}RT-ThreadlwIP驱动结构设备控制static

rt_err_t

rt_skeleton_control(rt_device_t

dev,

rt_uint8_t

cmd,

void

*args){struct

rt_skeleton_eth

*eth;eth

=

(struct

rt_skeleton_eth*)dev;RT_ASSERT(eth

!=

RT_NULL);switch

(cmd){case

NIOCTL_GADDR:/*

get

mac

address

*/if

(args)

rt_memcpy(args,

_skeleton_device.dev_addr,

6);else

return

-RT_ERROR;break;default

:break;}return

RT_EOK;}RT-ThreadlwIP驱动总结中断通知void

rt_skeleton_isr(int

irqno){rt_uint32_t

status;/*

read

status

*//*

Received

the

coming

packet

*/if

(status){/*

disable

receive

interrupt

*//*

a

frame

has

been

received

*/eth_device_ready(&(_skeleton_device.parent));}/*

Transmit

Interrupt

check

*/if

(status){}}RT-ThreadlwIP驱动总结接收struct

pbuf

*rt_skeltion_rx(struct

rt_device

*device){struct

pbuf

*p

=

RT_NULL;rt_uint32_t

pkt_len;/*

get

rx

packet

length

*/if

(pkt_len

>

0){p

=

pbuf_alloc(PBUF_LINK,

rx_len,

PBUF_RAM);/*

read

packet

to

pbuf

*/}else{/*

enable

interrupt

*/}return

p;}RT-ThreadlwIP驱动结构总结发送rt_err_t

rt_skeletion_tx(struct

rt_device

*device,

struct

pbuf*

p){struct

pbuf*

q;for

(q

=

p;

q

!=

RT_NULL;

q

=

q->next){/*

write

pbuf

to

device

*/}/*

wait

transmition

complete

*/return

RT_EOK;}MB9BF618网络驱动MB9BF618内置双EMAC，每个EMAC都单独有DMA。DMA描述符（初始化成DMA链）StatusBufferSizeBufferAddrNextDescAddrStatusBufferSizeBufferAddrNextDescAddrStatusBufferSizeBufferAddrNextDescAddrDescriptor

#1Descriptor

#2Descriptor

#3MB9BF618网络驱动发送时流程获取信号量（tx_buf_free）写入pbuf到DMA

buffer中获得DMA

buffer触发发送DMADMAbuffer换下一个位置发送完成中断释放信号量（tx_buf_free）MB9BF618网络驱动接收流程检查当前DMAbuffer状态分配pbuf，并读出数据到pbuf获得有效数据长度清除DMA

buffer状态DMAbuffer换下一个位置接收中断eth_device_ready();lwIP代码结构tcp主线程，tcpip.c入口：void

tcpip_thread(void*

arg)case

TCPIP_MSG_API:break;case

TCPIP_MSG_INPKT:break;case

TCPIP_MSG_NETIFAPI:break;case

TCPIP_MSG_TIMEOUT/UNTIMEOUT:break;case

TCPIP_MSG_CALLBACK:break;case

TCPIP_MSG_CALLBACK_STATIC:break;接收到数据包。回调消息。lwIP代码结构应用TCPIPETX网卡lwip_sendtoTCPIP_API_MSGnetif->outputethernetif_linkoutputfm3_emac_txlwIP代码结构以邮箱为基础；大多数工作都在tcp线程中完成；很多类似这样的代码：struct

api_msg

msg;msg.function

=

do_send;msg.msg.conn

=

conn;msg.msg.msg.b

=

buf;err

=

TCPIP_APIMSG(&msg);lwIP

pbuf，buffer管理nextpayloadtotal

lengthlengthtypeflagsrefpayloadnextpayloadtotal

lengthlengthtypeflagsrefpayloadfreespacenextpayloadtotal

lengthlengthtypeflagsreffreespacepayloadlwIP

pbuf，buffer管理struct

pbuf*

pbuf_alloc(pbuf_layer

layer,u16_t

length,

pbuf_type

type);u8_t

pbuf_free(struct

pbuf

*p);PBUF分配和释放u16_t

pbuf_copy_partial(struct

pbuf

*bu