u-boot/net/arp.c
2002-09-28 00:23:46 +00:00

121 lines
2.9 KiB
C

/*
* (C) Copyright 2000
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#include <common.h>
#include <command.h>
#include <net.h>
#include "bootp.h"
#include "tftp.h"
#include "arp.h"
#if (CONFIG_COMMANDS & CFG_CMD_NET)
#define TIMEOUT 5 /* Seconds before trying ARP again */
#ifndef CONFIG_NET_RETRY_COUNT
# define TIMEOUT_COUNT 5 /* # of timeouts before giving up */
#else
# define TIMEOUT_COUNT (CONFIG_NET_RETRY_COUNT)
#endif
static void ArpHandler(uchar *pkt, unsigned dest, unsigned src, unsigned len);
static void ArpTimeout(void);
int ArpTry = 0;
/*
* Handle a ARP received packet.
*/
static void
ArpHandler(uchar *pkt, unsigned dest, unsigned src, unsigned len)
{
/* Check if the frame is really an ARP reply */
if (memcmp (NetServerEther, NetBcastAddr, 6) != 0) {
#ifdef DEBUG
printf("Got good ARP - start TFTP\n");
#endif
TftpStart ();
}
}
/*
* Timeout on ARP request.
*/
static void
ArpTimeout(void)
{
if (ArpTry >= TIMEOUT_COUNT) {
puts ("\nRetry count exceeded; starting again\n");
NetStartAgain ();
} else {
NetSetTimeout (TIMEOUT * CFG_HZ, ArpTimeout);
ArpRequest ();
}
}
void
ArpRequest (void)
{
int i;
volatile uchar *pkt;
ARP_t * arp;
printf("ARP broadcast %d\n", ++ArpTry);
pkt = NetTxPacket;
NetSetEther(pkt, NetBcastAddr, PROT_ARP);
pkt += ETHER_HDR_SIZE;
arp = (ARP_t *)pkt;
arp->ar_hrd = htons(ARP_ETHER);
arp->ar_pro = htons(PROT_IP);
arp->ar_hln = 6;
arp->ar_pln = 4;
arp->ar_op = htons(ARPOP_REQUEST);
memcpy (&arp->ar_data[0], NetOurEther, 6); /* source ET addr */
NetWriteIP((uchar*)&arp->ar_data[6], NetOurIP); /* source IP addr */
for (i=10; i<16; ++i) {
arp->ar_data[i] = 0; /* dest ET addr = 0 */
}
if((NetServerIP & NetOurSubnetMask) != (NetOurIP & NetOurSubnetMask)) {
if (NetOurGatewayIP == 0) {
puts ("## Warning: gatewayip needed but not set\n");
}
NetWriteIP((uchar*)&arp->ar_data[16], NetOurGatewayIP);
} else {
NetWriteIP((uchar*)&arp->ar_data[16], NetServerIP);
}
NetSendPacket(NetTxPacket, ETHER_HDR_SIZE + ARP_HDR_SIZE);
NetSetTimeout(TIMEOUT * CFG_HZ, ArpTimeout);
NetSetHandler(ArpHandler);
}
#endif /* CFG_CMD_NET */