xref: /openbmc/u-boot/net/rarp.c (revision 53efa1f1)
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 #if defined(CONFIG_CMD_NET)
33 
34 #define TIMEOUT		5000UL	/* Milliseconds before trying BOOTP again */
35 #ifndef	CONFIG_NET_RETRY_COUNT
36 # define TIMEOUT_COUNT	5		/* # of timeouts before giving up  */
37 #else
38 # define TIMEOUT_COUNT  (CONFIG_NET_RETRY_COUNT)
39 #endif
40 
41 
42 int		RarpTry;
43 
44 /*
45  *	Handle a RARP received packet.
46  */
47 static void
48 RarpHandler(uchar * dummi0, unsigned dummi1, unsigned dummi2, unsigned dummi3)
49 {
50 	char *s;
51 	debug("Got good RARP\n");
52 	if ((s = getenv("autoload")) != NULL) {
53 		if (*s == 'n') {
54 			/*
55 			 * Just use RARP to configure system;
56 			 * Do not use TFTP/NFS to to load the bootfile.
57 			 */
58 			NetState = NETLOOP_SUCCESS;
59 			return;
60 #if defined(CONFIG_CMD_NFS)
61 		} else if ((s != NULL) && !strcmp(s, "NFS")) {
62 			NfsStart();
63 			return;
64 #endif
65 		}
66 	}
67 	TftpStart ();
68 }
69 
70 
71 /*
72  *	Timeout on BOOTP request.
73  */
74 static void
75 RarpTimeout(void)
76 {
77 	if (RarpTry >= TIMEOUT_COUNT) {
78 		puts ("\nRetry count exceeded; starting again\n");
79 		NetStartAgain ();
80 	} else {
81 		NetSetTimeout (TIMEOUT, RarpTimeout);
82 		RarpRequest ();
83 	}
84 }
85 
86 
87 void
88 RarpRequest (void)
89 {
90 	int i;
91 	volatile uchar *pkt;
92 	ARP_t *	rarp;
93 
94 	printf("RARP broadcast %d\n", ++RarpTry);
95 	pkt = NetTxPacket;
96 
97 	pkt += NetSetEther(pkt, NetBcastAddr, PROT_RARP);
98 
99 	rarp = (ARP_t *)pkt;
100 
101 	rarp->ar_hrd = htons (ARP_ETHER);
102 	rarp->ar_pro = htons (PROT_IP);
103 	rarp->ar_hln = 6;
104 	rarp->ar_pln = 4;
105 	rarp->ar_op  = htons (RARPOP_REQUEST);
106 	memcpy (&rarp->ar_data[0],  NetOurEther, 6);	/* source ET addr */
107 	memcpy (&rarp->ar_data[6],  &NetOurIP,   4);	/* source IP addr */
108 	memcpy (&rarp->ar_data[10], NetOurEther, 6);	/* dest ET addr = source ET addr ??*/
109 	/* dest. IP addr set to broadcast */
110 	for (i = 0; i <= 3; i++) {
111 		rarp->ar_data[16 + i] = 0xff;
112 	}
113 
114 	NetSendPacket(NetTxPacket, (pkt - NetTxPacket) + ARP_HDR_SIZE);
115 
116 	NetSetTimeout(TIMEOUT, RarpTimeout);
117 	NetSetHandler(RarpHandler);
118 }
119 
120 #endif
121