[U-Boot-Users] [PATCH] net: make ARP timeout configurable

[Guennadi Liakhovetski]

Currently the timeout waiting for an ARP reply is hard set to 5 seconds. 
On i.MX31ADS due to a hardware "strangeness" up to four first IP packets 
to the boards get lost, which typically are ARP replies. By configuring 
the timeout to a lower value we significantly improve the first network 
transfer time on this board. The timeout is specified in deciseconds, 
because it has to be converted to hardware ticks, and CFG_HZ ranges from 
900 to 27000000 on different boards.

Signed-off-by: Guennadi Liakhovetski <lg at denx.de>

---

diff --git a/README b/README
index a9663a3..9249064 100644
--- a/README
+++ b/README
@@ -1547,6 +1547,10 @@ The following options need to be configured:
 		before giving up the operation. If not defined, a
 		default value of 5 is used.
 
+		CONFIG_ARP_TIMEOUT
+
+		Timeout waiting for an ARP reply in deciseconds.
+
 - Command Interpreter:
 		CONFIG_AUTO_COMPLETE
 
diff --git a/net/net.c b/net/net.c
index 44feee2..2128bd4 100644
--- a/net/net.c
+++ b/net/net.c
@@ -94,11 +94,16 @@
 
 DECLARE_GLOBAL_DATA_PTR;
 
-#define ARP_TIMEOUT		5UL		/* Seconds before trying ARP again */
+#ifndef	CONFIG_ARP_TIMEOUT
+# define ARP_TIMEOUT		50UL	/* Deciseconds before trying ARP again */
+#else
+# define ARP_TIMEOUT		CONFIG_ARP_TIMEOUT
+#endif
+
 #ifndef	CONFIG_NET_RETRY_COUNT
-# define ARP_TIMEOUT_COUNT	5		/* # of timeouts before giving up  */
+# define ARP_TIMEOUT_COUNT	5	/* # of timeouts before giving up  */
 #else
-# define ARP_TIMEOUT_COUNT  (CONFIG_NET_RETRY_COUNT)
+# define ARP_TIMEOUT_COUNT	CONFIG_NET_RETRY_COUNT
 #endif
 
 #if 0
@@ -129,7 +134,7 @@ uchar		NetOurEther[6];		/* Our ethernet address			*/
 uchar		NetServerEther[6] =	/* Boot server enet address		*/
 			{ 0, 0, 0, 0, 0, 0 };
 IPaddr_t	NetOurIP;		/* Our IP addr (0 = unknown)		*/
-IPaddr_t	NetServerIP;		/* Our IP addr (0 = unknown)		*/
+IPaddr_t	NetServerIP;		/* Server IP addr (0 = unknown)		*/
 volatile uchar *NetRxPkt;		/* Current receive packet		*/
 int		NetRxPktLen;		/* Current rx packet length		*/
 unsigned	NetIPID;		/* IP packet ID				*/
@@ -253,7 +258,7 @@ void ArpTimeoutCheck(void)
 	t = get_timer(0);
 
 	/* check for arp timeout */
-	if ((t - NetArpWaitTimerStart) > ARP_TIMEOUT * CFG_HZ) {
+	if ((t - NetArpWaitTimerStart) > ARP_TIMEOUT * CFG_HZ / 10) {
 		NetArpWaitTry++;
 
 		if (NetArpWaitTry >= ARP_TIMEOUT_COUNT) {
@@ -494,7 +499,7 @@ restart:
 		 *	Check the ethernet for a new packet.  The ethernet
 		 *	receive routine will process it.
 		 */
-			eth_rx();
+		eth_rx();
 
 		/*
 		 *	Abort if ctrl-c was pressed.