/** | |
* @file | |
* Ethernet Interface Skeleton | |
* | |
*/ | |
/* | |
* Copyright (c) 2001-2004 Swedish Institute of Computer Science. | |
* All rights reserved. | |
* | |
* Redistribution and use in source and binary forms, with or without modification, | |
* are permitted provided that the following conditions are met: | |
* | |
* 1. Redistributions of source code must retain the above copyright notice, | |
* this list of conditions and the following disclaimer. | |
* 2. Redistributions in binary form must reproduce the above copyright notice, | |
* this list of conditions and the following disclaimer in the documentation | |
* and/or other materials provided with the distribution. | |
* 3. The name of the author may not be used to endorse or promote products | |
* derived from this software without specific prior written permission. | |
* | |
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED | |
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF | |
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT | |
* SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT | |
* OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | |
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | |
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING | |
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY | |
* OF SUCH DAMAGE. | |
* | |
* This file is part of the lwIP TCP/IP stack. | |
* | |
* Author: Adam Dunkels <adam@sics.se> | |
* | |
*/ | |
/* | |
* This file is a skeleton for developing Ethernet network interface | |
* drivers for lwIP. Add code to the low_level functions and do a | |
* search-and-replace for the word "ethernetif" to replace it with | |
* something that better describes your network interface. | |
*/ | |
#include "lwip/opt.h" | |
#if 0 /* don't build, this is only a skeleton, see previous comment */ | |
#include "lwip/def.h" | |
#include "lwip/mem.h" | |
#include "lwip/pbuf.h" | |
#include "lwip/sys.h" | |
#include <lwip/stats.h> | |
#include <lwip/snmp.h> | |
#include "netif/etharp.h" | |
#include "netif/ppp_oe.h" | |
/* Define those to better describe your network interface. */ | |
#define IFNAME0 'e' | |
#define IFNAME1 'n' | |
/** | |
* Helper struct to hold private data used to operate your ethernet interface. | |
* Keeping the ethernet address of the MAC in this struct is not necessary | |
* as it is already kept in the struct netif. | |
* But this is only an example, anyway... | |
*/ | |
struct ethernetif { | |
struct eth_addr *ethaddr; | |
/* Add whatever per-interface state that is needed here. */ | |
}; | |
/* Forward declarations. */ | |
static void ethernetif_input(struct netif *netif); | |
/** | |
* In this function, the hardware should be initialized. | |
* Called from ethernetif_init(). | |
* | |
* @param netif the already initialized lwip network interface structure | |
* for this ethernetif | |
*/ | |
static void | |
low_level_init(struct netif *netif) | |
{ | |
struct ethernetif *ethernetif = netif->state; | |
/* set MAC hardware address length */ | |
netif->hwaddr_len = ETHARP_HWADDR_LEN; | |
/* set MAC hardware address */ | |
netif->hwaddr[0] = ; | |
... | |
netif->hwaddr[5] = ; | |
/* maximum transfer unit */ | |
netif->mtu = 1500; | |
/* device capabilities */ | |
/* don't set NETIF_FLAG_ETHARP if this device is not an ethernet one */ | |
netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP; | |
/* Do whatever else is needed to initialize interface. */ | |
} | |
/** | |
* This function should do the actual transmission of the packet. The packet is | |
* contained in the pbuf that is passed to the function. This pbuf | |
* might be chained. | |
* | |
* @param netif the lwip network interface structure for this ethernetif | |
* @param p the MAC packet to send (e.g. IP packet including MAC addresses and type) | |
* @return ERR_OK if the packet could be sent | |
* an err_t value if the packet couldn't be sent | |
* | |
* @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to | |
* strange results. You might consider waiting for space in the DMA queue | |
* to become availale since the stack doesn't retry to send a packet | |
* dropped because of memory failure (except for the TCP timers). | |
*/ | |
static err_t | |
low_level_output(struct netif *netif, struct pbuf *p) | |
{ | |
struct ethernetif *ethernetif = netif->state; | |
struct pbuf *q; | |
initiate transfer(); | |
#if ETH_PAD_SIZE | |
pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */ | |
#endif | |
for(q = p; q != NULL; q = q->next) { | |
/* Send the data from the pbuf to the interface, one pbuf at a | |
time. The size of the data in each pbuf is kept in the ->len | |
variable. */ | |
send data from(q->payload, q->len); | |
} | |
signal that packet should be sent(); | |
#if ETH_PAD_SIZE | |
pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */ | |
#endif | |
LINK_STATS_INC(link.xmit); | |
return ERR_OK; | |
} | |
/** | |
* Should allocate a pbuf and transfer the bytes of the incoming | |
* packet from the interface into the pbuf. | |
* | |
* @param netif the lwip network interface structure for this ethernetif | |
* @return a pbuf filled with the received packet (including MAC header) | |
* NULL on memory error | |
*/ | |
static struct pbuf * | |
low_level_input(struct netif *netif) | |
{ | |
struct ethernetif *ethernetif = netif->state; | |
struct pbuf *p, *q; | |
u16_t len; | |
/* Obtain the size of the packet and put it into the "len" | |
variable. */ | |
len = ; | |
#if ETH_PAD_SIZE | |
len += ETH_PAD_SIZE; /* allow room for Ethernet padding */ | |
#endif | |
/* We allocate a pbuf chain of pbufs from the pool. */ | |
p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL); | |
if (p != NULL) { | |
#if ETH_PAD_SIZE | |
pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */ | |
#endif | |
/* We iterate over the pbuf chain until we have read the entire | |
* packet into the pbuf. */ | |
for(q = p; q != NULL; q = q->next) { | |
/* Read enough bytes to fill this pbuf in the chain. The | |
* available data in the pbuf is given by the q->len | |
* variable. */ | |
read data into(q->payload, q->len); | |
} | |
acknowledge that packet has been read(); | |
#if ETH_PAD_SIZE | |
pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */ | |
#endif | |
LINK_STATS_INC(link.recv); | |
} else { | |
drop packet(); | |
LINK_STATS_INC(link.memerr); | |
LINK_STATS_INC(link.drop); | |
} | |
return p; | |
} | |
/** | |
* This function should be called when a packet is ready to be read | |
* from the interface. It uses the function low_level_input() that | |
* should handle the actual reception of bytes from the network | |
* interface. Then the type of the received packet is determined and | |
* the appropriate input function is called. | |
* | |
* @param netif the lwip network interface structure for this ethernetif | |
*/ | |
static void | |
ethernetif_input(struct netif *netif) | |
{ | |
struct ethernetif *ethernetif; | |
struct eth_hdr *ethhdr; | |
struct pbuf *p; | |
ethernetif = netif->state; | |
/* move received packet into a new pbuf */ | |
p = low_level_input(netif); | |
/* no packet could be read, silently ignore this */ | |
if (p == NULL) return; | |
/* points to packet payload, which starts with an Ethernet header */ | |
ethhdr = p->payload; | |
switch (htons(ethhdr->type)) { | |
/* IP or ARP packet? */ | |
case ETHTYPE_IP: | |
case ETHTYPE_ARP: | |
#if PPPOE_SUPPORT | |
/* PPPoE packet? */ | |
case ETHTYPE_PPPOEDISC: | |
case ETHTYPE_PPPOE: | |
#endif /* PPPOE_SUPPORT */ | |
/* full packet send to tcpip_thread to process */ | |
if (netif->input(p, netif)!=ERR_OK) | |
{ LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n")); | |
pbuf_free(p); | |
p = NULL; | |
} | |
break; | |
default: | |
pbuf_free(p); | |
p = NULL; | |
break; | |
} | |
} | |
/** | |
* Should be called at the beginning of the program to set up the | |
* network interface. It calls the function low_level_init() to do the | |
* actual setup of the hardware. | |
* | |
* This function should be passed as a parameter to netif_add(). | |
* | |
* @param netif the lwip network interface structure for this ethernetif | |
* @return ERR_OK if the loopif is initialized | |
* ERR_MEM if private data couldn't be allocated | |
* any other err_t on error | |
*/ | |
err_t | |
ethernetif_init(struct netif *netif) | |
{ | |
struct ethernetif *ethernetif; | |
LWIP_ASSERT("netif != NULL", (netif != NULL)); | |
ethernetif = mem_malloc(sizeof(struct ethernetif)); | |
if (ethernetif == NULL) { | |
LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_init: out of memory\n")); | |
return ERR_MEM; | |
} | |
#if LWIP_NETIF_HOSTNAME | |
/* Initialize interface hostname */ | |
netif->hostname = "lwip"; | |
#endif /* LWIP_NETIF_HOSTNAME */ | |
/* | |
* Initialize the snmp variables and counters inside the struct netif. | |
* The last argument should be replaced with your link speed, in units | |
* of bits per second. | |
*/ | |
NETIF_INIT_SNMP(netif, snmp_ifType_ethernet_csmacd, ???); | |
netif->state = ethernetif; | |
netif->name[0] = IFNAME0; | |
netif->name[1] = IFNAME1; | |
/* We directly use etharp_output() here to save a function call. | |
* You can instead declare your own function an call etharp_output() | |
* from it if you have to do some checks before sending (e.g. if link | |
* is available...) */ | |
netif->output = etharp_output; | |
netif->linkoutput = low_level_output; | |
ethernetif->ethaddr = (struct eth_addr *)&(netif->hwaddr[0]); | |
/* initialize the hardware */ | |
low_level_init(netif); | |
return ERR_OK; | |
} | |
#endif /* 0 */ |