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1 Introduction
To transplant LWIP 2.1.2 functions on the STM32 platform, you need to do some preparatory work first, such as:
- Download
lwip-2.1.2Information:contrib-2.1.0, ,STM32F4x7_ETH_LwIP_V1.1.1, Reference: "data preparation based on the STM32 transplant LWIP" - Prepare the FreeRTOS project that has been ported to STM32.
The target platform for transplantation is STM32F429 . It was mentioned in the previous data preparation that the STM32 official website has STM32F4x7 microcontrollers.LwIP TCP/IP protocol stackFor the demo code, we can refer to the target platform to a large extent.
2. System block diagram of STM32 running LwIP
We transplant LwIP on the STM32 platform, and mainly complete the following 4 parts:
- The RTOS : In the FreeRTOS STM32 running, and to LwIP providing protocol stacks
Mutex,Mail boxandCreate Threadother API interface. - Network System Config : Mainlysystem settingsfor the LwIP protocol stack.
- LwIP Stack : This is the LwIP 2.1.2 TCP/IP protocol stack, we only need to add the source code to the project.
- Driver Hardware : ETH main driver layer STM32 internet interface, for example:
GPIOs,clocks,MAC,DMAis provided.
The connection block diagram between these 4 parts is as follows:
3. Porting part of LwIP RTOS
For the transplantation of the LwIP RTOS part, we can refer to contrib-2.1.0 . This part mainly provides API interfaces for the LwIP protocol stack Mutex, Mail boxand so Create Threadon. Because each OS has different specific implementations of these API interfaces, LwIP officially provides a template. It happens that contrib-2.1.0 provides the implementation of these interfaces of FreeRTOS, we can directly transplant them, the code path is as follows:
PATH:contrib-2.1.0\ports\freertos\sys_arch.c
RTOS provides an interface to provide architecture, as follows:
4. Porting of LwIP System Config
For the transplantation of the LwIP System Config part, we can refer to STM32F4x7_ETH_LwIP_V1.1.1 (PATH: STM32F4x7_ETH_LwIP_V1.1.1\Project\FreeRTOS\udptcp_echo_server_netconn\src\netconf.c), the main steps are as follows:
- tcpip_init() : Mainly create a tcp_ip stack thread, and call a
lwip_init()function to initialize the LwIP protocol stack. - netif_add() : Apply for one
struct netif, set the default IP address, subnet mask and gateway, and add its network interface to itnetif_list. - netif_set_default() : Register the newly applied network interface as the default network interface.
- netif_set_up() : Start the network interface.
- dhcp_start() : Start DHCP to automatically obtain an IP address. If the default IP address is set, it may not be called. ( Note: Optional call )
There is a more important part of LwIP System Config, which is the header file of LwIP system option configuration lwipopts.h. My configuration here is as follows: (for reference only)
#ifndef __LWIPOPTS_H__
#define __LWIPOPTS_H__
/**
* SYS_LIGHTWEIGHT_PROT==1: if you want inter-task protection for certain
* critical regions during buffer allocation, deallocation and memory
* allocation and deallocation.
*/
#define SYS_LIGHTWEIGHT_PROT 0
#define ETHARP_TRUST_IP_MAC 0
#define IP_REASSEMBLY 0
#define IP_FRAG 0
#define ARP_QUEUEING 0
#define LWIP_IPV4 1
/**
* NO_SYS==1: Provides VERY minimal functionality. Otherwise,
* use lwIP facilities.
*/
#define NO_SYS 0
/* ---------- Memory options ---------- */
/* MEM_ALIGNMENT: should be set to the alignment of the CPU for which
lwIP is compiled. 4 byte alignment -> define MEM_ALIGNMENT to 4, 2
byte alignment -> define MEM_ALIGNMENT to 2. */
#define MEM_ALIGNMENT 4
/* MEM_SIZE: the size of the heap memory. If the application will send
a lot of data that needs to be copied, this should be set high. */
#define MEM_SIZE (5*1024)
/* MEMP_NUM_PBUF: the number of memp struct pbufs. If the application
sends a lot of data out of ROM (or other static memory), this
should be set high. */
#define MEMP_NUM_PBUF 100
/* MEMP_NUM_UDP_PCB: the number of UDP protocol control blocks. One
per active UDP "connection". */
#define MEMP_NUM_UDP_PCB 6
/* MEMP_NUM_TCP_PCB: the number of simulatenously active TCP
connections. */
#define MEMP_NUM_TCP_PCB 10
/* MEMP_NUM_TCP_PCB_LISTEN: the number of listening TCP
connections. */
#define MEMP_NUM_TCP_PCB_LISTEN 5
/* MEMP_NUM_TCP_SEG: the number of simultaneously queued TCP
segments. */
#define MEMP_NUM_TCP_SEG 20
/* MEMP_NUM_SYS_TIMEOUT: the number of simulateously active
timeouts. */
#define MEMP_NUM_SYS_TIMEOUT 10
/* ---------- Pbuf options ---------- */
/* PBUF_POOL_SIZE: the number of buffers in the pbuf pool. */
#define PBUF_POOL_SIZE 20
/* PBUF_POOL_BUFSIZE: the size of each pbuf in the pbuf pool. */
#define PBUF_POOL_BUFSIZE 500
/* ---------- TCP options ---------- */
#define LWIP_TCP 1
#define TCP_TTL 255
/* Controls if TCP should queue segments that arrive out of
order. Define to 0 if your device is low on memory. */
#define TCP_QUEUE_OOSEQ 0
/* TCP Maximum segment size. */
#define TCP_MSS (1500 - 40) /* TCP_MSS = (Ethernet MTU - IP header size - TCP header size) */
/* TCP sender buffer space (bytes). */
#define TCP_SND_BUF (5*TCP_MSS)
/* TCP_SND_QUEUELEN: TCP sender buffer space (pbufs). This must be at least
as much as (2 * TCP_SND_BUF/TCP_MSS) for things to work. */
#define TCP_SND_QUEUELEN (4* TCP_SND_BUF/TCP_MSS)
/* TCP receive window. */
#define TCP_WND (2*TCP_MSS)
/* ---------- ICMP options ---------- */
#define LWIP_ICMP 1
/* ---------- DHCP options ---------- */
/* Define LWIP_DHCP to 1 if you want DHCP configuration of
interfaces. DHCP is not implemented in lwIP 0.5.1, however, so
turning this on does currently not work. */
#define LWIP_DHCP 1
/* ---------- UDP options ---------- */
#define LWIP_UDP 1
#define UDP_TTL 255
/* ---------- Statistics options ---------- */
#define LWIP_STATS 0
#define LWIP_PROVIDE_ERRNO 1
/* ---------- link callback options ---------- */
/* LWIP_NETIF_LINK_CALLBACK==1: Support a callback function from an interface
* whenever the link changes (i.e., link down)
*/
#define LWIP_NETIF_LINK_CALLBACK 1
/*
--------------------------------------
---------- Checksum options ----------
--------------------------------------
*/
/*
The STM32F4x7 allows computing and verifying the IP, UDP, TCP and ICMP checksums by hardware:
- To use this feature let the following define uncommented.
- To disable it and process by CPU comment the the checksum.
*/
#define CHECKSUM_BY_HARDWARE
#ifdef CHECKSUM_BY_HARDWARE
/* CHECKSUM_GEN_IP==0: Generate checksums by hardware for outgoing IP packets.*/
#define CHECKSUM_GEN_IP 0
/* CHECKSUM_GEN_UDP==0: Generate checksums by hardware for outgoing UDP packets.*/
#define CHECKSUM_GEN_UDP 0
/* CHECKSUM_GEN_TCP==0: Generate checksums by hardware for outgoing TCP packets.*/
#define CHECKSUM_GEN_TCP 0
/* CHECKSUM_CHECK_IP==0: Check checksums by hardware for incoming IP packets.*/
#define CHECKSUM_CHECK_IP 0
/* CHECKSUM_CHECK_UDP==0: Check checksums by hardware for incoming UDP packets.*/
#define CHECKSUM_CHECK_UDP 0
/* CHECKSUM_CHECK_TCP==0: Check checksums by hardware for incoming TCP packets.*/
#define CHECKSUM_CHECK_TCP 0
/* CHECKSUM_CHECK_ICMP==0: Check checksums by hardware for incoming ICMP packets.*/
#define CHECKSUM_GEN_ICMP 0
#else
/* CHECKSUM_GEN_IP==1: Generate checksums in software for outgoing IP packets.*/
#define CHECKSUM_GEN_IP 1
/* CHECKSUM_GEN_UDP==1: Generate checksums in software for outgoing UDP packets.*/
#define CHECKSUM_GEN_UDP 1
/* CHECKSUM_GEN_TCP==1: Generate checksums in software for outgoing TCP packets.*/
#define CHECKSUM_GEN_TCP 1
/* CHECKSUM_CHECK_IP==1: Check checksums in software for incoming IP packets.*/
#define CHECKSUM_CHECK_IP 1
/* CHECKSUM_CHECK_UDP==1: Check checksums in software for incoming UDP packets.*/
#define CHECKSUM_CHECK_UDP 1
/* CHECKSUM_CHECK_TCP==1: Check checksums in software for incoming TCP packets.*/
#define CHECKSUM_CHECK_TCP 1
/* CHECKSUM_CHECK_ICMP==1: Check checksums by hardware for incoming ICMP packets.*/
#define CHECKSUM_GEN_ICMP 1
#endif
/*
----------------------------------------------
---------- Sequential layer options ----------
----------------------------------------------
*/
/**
* LWIP_NETCONN==1: Enable Netconn API (require to use api_lib.c)
*/
#define LWIP_NETCONN 1
/*
------------------------------------
---------- Socket options ----------
------------------------------------
*/
/**
* LWIP_SOCKET==1: Enable Socket API (require to use sockets.c)
*/
#define LWIP_SOCKET 0
/*
-----------------------------------
---------- DEBUG options ----------
-----------------------------------
*/
#define LWIP_DEBUG 0
/*
---------------------------------
---------- OS options ----------
---------------------------------
*/
#define TCPIP_THREAD_NAME "TCP/IP"
#define TCPIP_THREAD_STACKSIZE 1000
#define TCPIP_MBOX_SIZE 5
#define DEFAULT_UDP_RECVMBOX_SIZE 2000
#define DEFAULT_TCP_RECVMBOX_SIZE 2000
#define DEFAULT_ACCEPTMBOX_SIZE 2000
#define DEFAULT_THREAD_STACKSIZE 500
#define TCPIP_THREAD_PRIO 3
//#define LWIP_COMPAT_MUTEX 1
#endif /* __LWIPOPTS_H__ */
5. Porting of LwIP Stack
- Add the LwIP 2.1.2 source code to the project, respectively
api, ,core,netifdetailed as follows:
- Add the header file path of LwIP 2.1.2 to Keil:
6. Porting of LwIP Hardware Driver
The migration of the LwIP Hardware Driver part is mainly two files, as follows:
- bsp_eth.c : Mainly set up GPIOs, clocks, MAC, DMA of Ethernet, refer to:
STM32F4x7_ETH_LwIP_V1.1.1\Project\FreeRTOS\udptcp_echo_server_netconn\src\stm32f4x7_eth_bsp.c - ethernetif.c : Mainly create a
ETH_MACthread to read Ethernet messages.low_level_inputAfter receiving the message, it isethernet_inputpassed to the LwIP layer for analysisthrough the callback call. If the LwIP layer has a message to be sent, itethernet_outputislow_level_outputsent outbycalling the ETH Hardware Driver layer. reference:STM32F4x7_ETH_LwIP_V1.1.1\Utilities\Third_Party\lwip-1.4.1\port\STM32F4x7\FreeRTOS\ethernetif.c
7. Verification Test
Finally, the verification test is successful, as follows
8. Data download address
The complete code download address for successful transplantation is as follows:
https://download.csdn.net/download/ZHONGCAI0901/13100126