net/rarp.c

   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         5UL             /* Seconds 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 #ifdef  DEBUG
  52         puts ("Got good RARP\n");
  53 #endif
  54         if ((s = getenv("autoload")) != NULL) {
  55                 if (*s == 'n') {
  56                         /*
  57                          * Just use RARP to configure system;
  58                          * Do not use TFTP/NFS to to load the bootfile.
  59                          */
  60                         NetState = NETLOOP_SUCCESS;
  61                         return;
  62 #if defined(CONFIG_CMD_NFS)
  63                 } else if ((s != NULL) && !strcmp(s, "NFS")) {
  64                         NfsStart();
  65                         return;
  66 #endif
  67                 }
  68         }
  69         TftpStart ();
  70 }
  71
  72
  73 /*
  74  *      Timeout on BOOTP request.
  75  */
  76 static void
  77 RarpTimeout(void)
  78 {
  79         if (RarpTry >= TIMEOUT_COUNT) {
  80                 puts ("\nRetry count exceeded; starting again\n");
  81                 NetStartAgain ();
  82         } else {
  83                 NetSetTimeout (TIMEOUT * CFG_HZ, RarpTimeout);
  84                 RarpRequest ();
  85         }
  86 }
  87
  88
  89 void
  90 RarpRequest (void)
  91 {
  92         int i;
  93         volatile uchar *pkt;
  94         ARP_t * rarp;
  95
  96         printf("RARP broadcast %d\n", ++RarpTry);
  97         pkt = NetTxPacket;
  98
  99         pkt += NetSetEther(pkt, NetBcastAddr, PROT_RARP);
 100
 101         rarp = (ARP_t *)pkt;
 102
 103         rarp->ar_hrd = htons (ARP_ETHER);
 104         rarp->ar_pro = htons (PROT_IP);
 105         rarp->ar_hln = 6;
 106         rarp->ar_pln = 4;
 107         rarp->ar_op  = htons (RARPOP_REQUEST);
 108         memcpy (&rarp->ar_data[0],  NetOurEther, 6);    /* source ET addr */
 109         memcpy (&rarp->ar_data[6],  &NetOurIP,   4);    /* source IP addr */
 110         memcpy (&rarp->ar_data[10], NetOurEther, 6);    /* dest ET addr = source ET addr ??*/
 111         /* dest. IP addr set to broadcast */
 112         for (i = 0; i <= 3; i++) {
 113                 rarp->ar_data[16 + i] = 0xff;
 114         }
 115
 116         NetSendPacket(NetTxPacket, (pkt - NetTxPacket) + ARP_HDR_SIZE);
 117
 118         NetSetTimeout(TIMEOUT * CFG_HZ, RarpTimeout);
 119         NetSetHandler(RarpHandler);
 120 }
 121
 122 #endif