Das U-Boot: Universal Boot Loader

diff --git a/net/arp.c b/net/arp.c
new file mode 100644 (file)
index 0000000..c09dc1a
--- /dev/null
+++ b/net/arp.c
@@ -0,0 +1,120 @@
+/*
+ * (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 */