xref: /openbmc/u-boot/net/rarp.c (revision e2a53458)
1 /*
2  * (C) Copyright 2000-2002
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * See file CREDITS for list of people who contributed to this
6  * project.
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 of
11  * the License, or (at your option) any later version.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License
19  * along with this program; if not, write to the Free Software
20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
21  * MA 02111-1307 USA
22  */
23 
24 #include <common.h>
25 #include <command.h>
26 #include <net.h>
27 #include "nfs.h"
28 #include "bootp.h"
29 #include "rarp.h"
30 #include "tftp.h"
31 
32 #define TIMEOUT		5000UL	/* Milliseconds before trying BOOTP again */
33 #ifndef	CONFIG_NET_RETRY_COUNT
34 # define TIMEOUT_COUNT	5		/* # of timeouts before giving up  */
35 #else
36 # define TIMEOUT_COUNT  (CONFIG_NET_RETRY_COUNT)
37 #endif
38 
39 
40 int		RarpTry;
41 
42 /*
43  *	Handle a RARP received packet.
44  */
45 static void
46 RarpHandler(uchar *dummi0, unsigned dummi1, IPaddr_t sip, unsigned dummi2,
47 	    unsigned dummi3)
48 {
49 	char *s;
50 	debug("Got good RARP\n");
51 	if ((s = getenv("autoload")) != NULL) {
52 		if (*s == 'n') {
53 			/*
54 			 * Just use RARP to configure system;
55 			 * Do not use TFTP/NFS to to load the bootfile.
56 			 */
57 			NetState = NETLOOP_SUCCESS;
58 			return;
59 #if defined(CONFIG_CMD_NFS)
60 		} else if ((s != NULL) && !strcmp(s, "NFS")) {
61 			NfsStart();
62 			return;
63 #endif
64 		}
65 	}
66 	TftpStart ();
67 }
68 
69 
70 /*
71  *	Timeout on BOOTP request.
72  */
73 static void
74 RarpTimeout(void)
75 {
76 	if (RarpTry >= TIMEOUT_COUNT) {
77 		puts ("\nRetry count exceeded; starting again\n");
78 		NetStartAgain ();
79 	} else {
80 		NetSetTimeout (TIMEOUT, RarpTimeout);
81 		RarpRequest ();
82 	}
83 }
84 
85 
86 void
87 RarpRequest (void)
88 {
89 	int i;
90 	volatile uchar *pkt;
91 	ARP_t *	rarp;
92 
93 	printf("RARP broadcast %d\n", ++RarpTry);
94 	pkt = NetTxPacket;
95 
96 	pkt += NetSetEther(pkt, NetBcastAddr, PROT_RARP);
97 
98 	rarp = (ARP_t *)pkt;
99 
100 	rarp->ar_hrd = htons (ARP_ETHER);
101 	rarp->ar_pro = htons (PROT_IP);
102 	rarp->ar_hln = 6;
103 	rarp->ar_pln = 4;
104 	rarp->ar_op  = htons (RARPOP_REQUEST);
105 	memcpy (&rarp->ar_data[0],  NetOurEther, 6);	/* source ET addr */
106 	memcpy (&rarp->ar_data[6],  &NetOurIP,   4);	/* source IP addr */
107 	memcpy (&rarp->ar_data[10], NetOurEther, 6);	/* dest ET addr = source ET addr ??*/
108 	/* dest. IP addr set to broadcast */
109 	for (i = 0; i <= 3; i++) {
110 		rarp->ar_data[16 + i] = 0xff;
111 	}
112 
113 	NetSendPacket(NetTxPacket, (pkt - NetTxPacket) + ARP_HDR_SIZE);
114 
115 	NetSetTimeout(TIMEOUT, RarpTimeout);
116 	NetSetHandler(RarpHandler);
117 }
118