mirror of https://github.com/ARMmbed/mbed-os.git
Implement low-level Ethernet interface for lwIP
Based on lwip_ethernetif.c skeleton file, use init, receive and transfer functionality of SMSC9220 Ethernet driver for the lightweight IP stack. Receive mechanism is interrupt driven. HW buffer sizes: Tx = 4608 bytes (MTU) Rx = 10560 bytes lwIP fine tuning: mbed-os/features/FEATURE_LWIP/lwip-interface/lwip/src/include/lwip/opt.h Change-Id: I0ea95650c65fb32cafb5c2d3dde11420c61dba66 Signed-off-by: Gabor Kertesz <gabor.kertesz@arm.com>pull/4596/head
gabker01
adbridge
parent
87d4003edb
commit
9b890198dd
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/* Copyright (c) 2017 ARM Limited
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#ifndef LWIPOPTS_CONF_H
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#define LWIPOPTS_CONF_H
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#define LWIP_TRANSPORT_ETHERNET 1
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/* The IEEE 802.3ac standard says the maximum Ethernet frame */
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/* size is 1522 bytes to accommodate the four-byte VLAN tag. */
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#define ETH_MAX_FLEN 1522u /* recommended size for a VLAN frame */
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/* Maximum Transfer Unit
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* The IEEE 802.3 specification limits the data portion of the 802.3 frame
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* to a minimum of 46 and a maximum of 1500 bytes, this is on L3 level.
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*/
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#define ETH_L2_HEADER_LEN 22u
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#define ETH_MAX_PAYLOAD_LEN (ETH_MAX_FLEN - ETH_L2_HEADER_LEN)
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#endif /* LWIPOPTS_CONF_H */
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@ -0,0 +1,397 @@
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/* mbed Microcontroller Library
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* Copyright (c) 2017 ARM Limited
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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#include <ctype.h>
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#include <stdio.h>
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#include <string.h>
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#include <stdlib.h>
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#include "ethernet_api.h"
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#include "eth_arch.h"
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#include "lwip/def.h"
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#include "lwip/ethip6.h"
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#include "lwip/igmp.h"
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#include "lwip/mem.h"
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#include "lwip/mld6.h"
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#include "lwip/opt.h"
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#include "lwip/pbuf.h"
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#include "lwip/snmp.h"
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#include "lwip/stats.h"
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#include "lwip/sys.h"
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#include "lwip/tcpip.h"
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#include "mbed_interface.h"
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#include "mbed_wait_api.h"
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#include "netif/etharp.h"
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#include "netif/ppp/pppoe.h"
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#include "smsc9220_eth.h"
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#include "sys_arch.h"
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/**
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* @file mps2_emac.c
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*
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* @brief Connects the lwIP stack to the SMSC9220 Ethernet controller driver,
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* by implementing the low-level Ethernet interface layer of lwIP,
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* according to the skeleton file:
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* \mbed-os\features\FEATURE_LWIP\lwip-interface\lwip\src\netif\lwip_ethernetif.c
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*
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*/
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#define HOSTNAME_STRING "lwip_mps2"
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static sys_sem_t rx_ready_sem;
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struct ethernetif {
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const struct eth_addr *ethaddr;
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int is_enabled;
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sys_mutex_t tx_mutex;
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};
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/**
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* Should allocate a pbuf and transfer the bytes of the incoming
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* packet from the interface into the pbuf.
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*
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* @param netif the lwip network interface structure for this ethernetif
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* @return a pbuf filled with the received packet (including MAC header)
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* NULL on memory error
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*/
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static struct pbuf *low_level_input(struct netif *netif)
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{
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struct pbuf *p, *q;
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uint16_t len;
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int unread_bytes = 0;
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len = ETH_MAX_FLEN;
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#if ETH_PAD_SIZE
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len += ETH_PAD_SIZE; /* allow room for Ethernet padding */
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#endif
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/* We allocate a pbuf chain of pbufs from the pool. */
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p = pbuf_alloc(PBUF_RAW, len, PBUF_POOL);
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if (p != NULL) {
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#if ETH_PAD_SIZE
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pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
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#endif
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/* It iterates over the pbuf chain until it has read the entire
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* packet into the pbuf. */
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for (q = p; q != NULL; q = q->next) {
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/* Read enough bytes to fill this pbuf in the chain. The
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* available data in the pbuf is given by the q->len
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* variable.
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* This does not necessarily have to be a memcpy, you can also preallocate
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* pbufs for a DMA-enabled MAC and after receiving truncate it to the
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* actually received size. In this case, ensure the tot_len member of the
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* pbuf is the sum of the chained pbuf len members.
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*/
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unread_bytes = ethernet_read(q->payload, q->len);
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if (unread_bytes == 0) {
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break;
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}
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}
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/* package has been read */
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MIB2_STATS_NETIF_ADD(netif, ifinoctets, p->tot_len);
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if (((u8_t*)p->payload)[0] & 1) {
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/* broadcast or multicast packet */
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MIB2_STATS_NETIF_INC(netif, ifinnucastpkts);
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} else {
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/* unicast packet */
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MIB2_STATS_NETIF_INC(netif, ifinucastpkts);
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}
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#if ETH_PAD_SIZE
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pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
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#endif
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LINK_STATS_INC(link.recv);
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} else {
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/* drop packet */
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LINK_STATS_INC(link.memerr);
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LINK_STATS_INC(link.drop);
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MIB2_STATS_NETIF_INC(netif, ifindiscards);
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}
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return p;
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}
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/**
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* This function should be called when a packet is ready to be read
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* from the interface. It uses the function low_level_input() that
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* should handle the actual reception of bytes from the network
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* interface. Then the type of the received packet is determined and
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* the appropriate input function is called.
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*
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* @param netif the lwip network interface structure for this ethernetif
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*/
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static void ethernetif_input(struct netif *netif)
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{
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struct pbuf *p;
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/* move received packet into a new pbuf */
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p = low_level_input(netif);
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/* if no packet could be read, silently ignore this */
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if (p != NULL) {
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/* pass all packets to ethernet_input, which decides what packets it supports */
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if (netif->input(p, netif) != ERR_OK) {
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LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: IP input error\n"));
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pbuf_free(p);
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}
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} else {
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LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_input: buffer null pointer error\n"));
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}
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}
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/**
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* This task is called when a packet is received. It will
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* pass the packet to the LWIP core.
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*
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* @param pvParameters pointer to the interface data
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*/
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static void packet_rx(void* pvParameters)
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{
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struct netif *netif = pvParameters;
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while (1) {
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sys_arch_sem_wait(&rx_ready_sem, 0);
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ethernetif_input(netif);
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smsc9220_enable_interrupt(enum_smsc9220_interrupt_rxstatus_fifo_level);
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}
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}
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/**
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* This function should do the actual transmission of the packet. The packet is
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* contained in the pbuf that is passed to the function. This pbuf
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* might be chained.
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*
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* @param netif the lwip network interface structure for this ethernetif
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* @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
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* @return ERR_OK if the packet could be sent
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* an err_t value if the packet couldn't be sent
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*
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* @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
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* strange results. You might consider waiting for space in the DMA queue
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* to become available since the stack doesn't retry to send a packet
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* dropped because of memory failure (except for the TCP timers).
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*/
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static err_t low_level_output(struct netif *netif, struct pbuf *p)
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{
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struct pbuf *q;
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err_t error = ERR_OK;
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unsigned int is_new_packet = 1;
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const unsigned int packet_length = p->tot_len;
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#if ETH_PAD_SIZE
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pbuf_header(p, -ETH_PAD_SIZE); /* drop the padding word */
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#endif
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/* fragmented packet sending should not be used concurrently */
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sys_mutex_lock(&(((struct ethernetif*)(netif->state))->tx_mutex));
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for (q = p; (q != NULL) && (error == ERR_OK); q = q->next) {
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/* Send the data from the pbuf to the interface, one pbuf at a
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* time.
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* The SMSC9220 driver should be used directly for sending by
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* buffer chain, because the SMSC9220 Ethernet API cannot support
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* ethernet_send and ethernet_write functions without additional
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* SW FIFO, what would increase the memory footprint.
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*/
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error = smsc9220_send_by_chunks(packet_length, is_new_packet,
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q->payload, q->len);
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if (error != ERR_OK) {
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LWIP_ASSERT("smsc9220_send_by_chunks error", 0);
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return error;
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}
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is_new_packet = 0;
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}
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sys_mutex_unlock(&(((struct ethernetif*)(netif->state))->tx_mutex));
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/* packet should be sent now */
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MIB2_STATS_NETIF_ADD(netif, ifoutoctets, p->tot_len);
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if (((u8_t*)p->payload)[0] & 1) {
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/* broadcast or multicast packet */
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MIB2_STATS_NETIF_INC(netif, ifoutnucastpkts);
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} else {
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/* unicast packet */
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MIB2_STATS_NETIF_INC(netif, ifoutucastpkts);
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}
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/* increase ifoutdiscards or ifouterrors on error */
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#if ETH_PAD_SIZE
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pbuf_header(p, ETH_PAD_SIZE); /* reclaim the padding word */
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#endif
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LINK_STATS_INC(link.xmit);
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return error;
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}
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/**
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* In this function, the hardware should be initialized.
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* Called from ethernetif_init().
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*
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* @param netif the already initialized lwip network interface structure
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* for this ethernetif
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*/
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static err_t low_level_init(struct netif *netif)
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{
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err_t error = ERR_OK;
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int low_level_error = 0;
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/* set MAC hardware address length */
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netif->hwaddr_len = ETHARP_HWADDR_LEN;
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/* set MAC hardware address */
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#if (MBED_MAC_ADDRESS_SUM != MBED_MAC_ADDR_INTERFACE)
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netif->hwaddr[0] = MBED_MAC_ADDR_0;
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netif->hwaddr[1] = MBED_MAC_ADDR_1;
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netif->hwaddr[2] = MBED_MAC_ADDR_2;
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netif->hwaddr[3] = MBED_MAC_ADDR_3;
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netif->hwaddr[4] = MBED_MAC_ADDR_4;
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netif->hwaddr[5] = MBED_MAC_ADDR_5;
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#else
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ethernet_address((char *)netif->hwaddr);
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#endif
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/* device capabilities */
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/* don't set NETIF_FLAG_ETHARP if this device is not an ethernet one */
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netif->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP;
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#if LWIP_IPV6 && LWIP_IPV6_MLD
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/*
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* For hardware/netifs that implement MAC filtering.
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* All-nodes link-local is handled by default, so it must let the hardware know
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* to allow multicast packets in.
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* Should set mld_mac_filter previously. */
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if (netif->mld_mac_filter != NULL) {
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ip6_addr_t ip6_allnodes_ll;
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ip6_addr_set_allnodes_linklocal(&ip6_allnodes_ll);
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netif->mld_mac_filter(netif, &ip6_allnodes_ll, MLD6_ADD_MAC_FILTER);
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}
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#endif /* LWIP_IPV6 && LWIP_IPV6_MLD */
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low_level_error = ethernet_init();
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if (low_level_error != 0) {
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return ERR_IF;
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}
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error = sys_mutex_new(&(((struct ethernetif*)(netif->state))->tx_mutex));
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/* Maximum Transfer Unit */
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netif->mtu = ETH_MAX_PAYLOAD_LEN;
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return error;
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}
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/**
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* Should be called at the beginning of the program to set up the
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* network interface. It calls the function low_level_init() to do the
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* actual setup of the hardware.
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*
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* This function should be passed as a parameter to netif_add().
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*
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* @param netif the lwip network interface structure for this ethernetif
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* @return ERR_OK if the loopif is initialized
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* ERR_MEM if private data couldn't be allocated
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* any other err_t on error
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*/
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err_t eth_arch_enetif_init(struct netif *netif)
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{
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err_t error = ERR_OK;
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struct ethernetif *ethernetif;
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ethernetif->is_enabled = 0;
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LWIP_ASSERT("netif != NULL", (netif != NULL));
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ethernetif = mem_malloc(sizeof(struct ethernetif));
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if (ethernetif == NULL) {
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LWIP_DEBUGF(NETIF_DEBUG, ("ethernetif_init: out of memory\n"));
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return ERR_MEM;
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}
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#if LWIP_NETIF_HOSTNAME
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/* Initialize interface hostname */
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netif->hostname = HOSTNAME_STRING;
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|
#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.
|
||||||
|
*/
|
||||||
|
MIB2_INIT_NETIF(netif, snmp_ifType_ethernet_csmacd,
|
||||||
|
LINK_SPEED_OF_YOUR_NETIF_IN_BPS);
|
||||||
|
|
||||||
|
netif->state = ethernetif;
|
||||||
|
/* Two-character name, "en" for Ethernet.
|
||||||
|
* This can be used to get a netif by name, via netif_find */
|
||||||
|
netif->name[0] = 'e';
|
||||||
|
netif->name[1] = 'n';
|
||||||
|
/* 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;
|
||||||
|
#if LWIP_IPV6
|
||||||
|
netif->output_ip6 = ethip6_output;
|
||||||
|
#endif /* LWIP_IPV6 */
|
||||||
|
netif->linkoutput = low_level_output;
|
||||||
|
|
||||||
|
ethernetif->ethaddr = (struct eth_addr *)&(netif->hwaddr[0]);
|
||||||
|
|
||||||
|
/* initialize the hardware */
|
||||||
|
error = low_level_init(netif);
|
||||||
|
|
||||||
|
if (error == ERR_OK) {
|
||||||
|
sys_thread_new("receive_thread", packet_rx, netif,
|
||||||
|
DEFAULT_THREAD_STACKSIZE, osPriorityNormal);
|
||||||
|
sys_sem_new(&rx_ready_sem, 0);
|
||||||
|
ethernetif->is_enabled = 1;
|
||||||
|
}
|
||||||
|
|
||||||
|
return error;
|
||||||
|
}
|
||||||
|
|
||||||
|
void eth_arch_enable_interrupts(void)
|
||||||
|
{
|
||||||
|
smsc9220_enable_interrupt(enum_smsc9220_interrupt_rxstatus_fifo_level);
|
||||||
|
NVIC_EnableIRQ(ETHERNET_IRQn);
|
||||||
|
}
|
||||||
|
|
||||||
|
void eth_arch_disable_interrupts(void)
|
||||||
|
{
|
||||||
|
NVIC_DisableIRQ(ETHERNET_IRQn);
|
||||||
|
}
|
||||||
|
|
||||||
|
void ETHERNET_IRQHandler(void)
|
||||||
|
{
|
||||||
|
if (smsc9220_get_interrupt(enum_smsc9220_interrupt_rxstatus_fifo_level)) {
|
||||||
|
sys_sem_signal(&rx_ready_sem);
|
||||||
|
smsc9220_clear_interrupt(enum_smsc9220_interrupt_rxstatus_fifo_level);
|
||||||
|
smsc9220_disable_interrupt(enum_smsc9220_interrupt_rxstatus_fifo_level);
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
/**
|
||||||
|
* @}
|
||||||
|
*/
|
||||||
|
|
||||||
|
/* --------------------------------- End Of File ------------------------------ */
|
||||||
|
|
||||||
|
|
@ -0,0 +1,24 @@
|
||||||
|
/* mbed Microcontroller Library
|
||||||
|
|
||||||
|
* Copyright (c) 2006-2017 ARM Limited
|
||||||
|
*
|
||||||
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
||||||
|
* you may not use this file except in compliance with the License.
|
||||||
|
* You may obtain a copy of the License at
|
||||||
|
*
|
||||||
|
* http://www.apache.org/licenses/LICENSE-2.0
|
||||||
|
*
|
||||||
|
* Unless required by applicable law or agreed to in writing, software
|
||||||
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
||||||
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||||||
|
* See the License for the specific language governing permissions and
|
||||||
|
* limitations under the License.
|
||||||
|
*/
|
||||||
|
|
||||||
|
#include "smsc9220_eth.h"
|
||||||
|
|
||||||
|
/* Provide ethernet devices with a semi-unique MAC address from the UUID */
|
||||||
|
void mbed_mac_address(char *mac)
|
||||||
|
{
|
||||||
|
smsc9220_read_mac_address(mac);
|
||||||
|
}
|
||||||
Loading…
Reference in New Issue