mgcoge make ether_scc.c work with CONFIG_NET_MULTI

This change is needed for mgcoge because it uses two ethernet drivers.

Add a check for the presence of the PIGGY board on mgcoge.  Without this
board networking cannot work and the initialization must be aborted.

Only allocate rtx once to prevent DPRAM exhaustion.

Initialize ether_scc.c and the keymile-specific HDLC driver (to be added
soon) in eth.c.

Signed-off-by: Gary Jennejohn <garyj@denx.de>
Signed-off-by: Ben Warren <biggerbadderben@gmail.com>
diff --git a/cpu/mpc8260/ether_scc.c b/cpu/mpc8260/ether_scc.c
index c65f0e0..3671ef1 100644
--- a/cpu/mpc8260/ether_scc.c
+++ b/cpu/mpc8260/ether_scc.c
@@ -10,6 +10,12 @@
  * Advent Networks, Inc. <http://www.adventnetworks.com>
  * Jay Monkman <jtm@smoothsmoothie.com>
  *
+ * Modified so that it plays nicely when more than one ETHERNET interface
+ * is in use a la ether_fcc.c.
+ * (C) Copyright 2008
+ * DENX Software Engineerin GmbH
+ * Gary Jennejohn <garyj@denx.de>
+ *
  * See file CREDITS for list of people who contributed to this
  * project.
  *
@@ -32,11 +38,14 @@
 #include <common.h>
 #include <asm/cpm_8260.h>
 #include <mpc8260.h>
+#include <malloc.h>
 #include <net.h>
 #include <command.h>
 #include <config.h>
 
-#if defined(CONFIG_ETHER_ON_SCC) && defined(CONFIG_CMD_NET)
+#ifndef CONFIG_NET_MULTI
+#error "CONFIG_NET_MULTI must be defined."
+#endif
 
 #if (CONFIG_ETHER_INDEX == 1)
 #  define PROFF_ENET            PROFF_SCC1
@@ -100,7 +109,7 @@
 static RTXBD *rtx;
 
 
-int eth_send(volatile void *packet, int length)
+static int sec_send(struct eth_device *dev, volatile void *packet, int length)
 {
     int i;
     int result = 0;
@@ -137,7 +146,7 @@
 }
 
 
-int eth_rx(void)
+static int sec_rx(struct eth_device *dev)
 {
     int length;
 
@@ -184,7 +193,7 @@
  *
  *************************************************************/
 
-int eth_init(bd_t *bis)
+static int sec_init(struct eth_device *dev, bd_t *bis)
 {
     int i;
     volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
@@ -194,9 +203,14 @@
     rxIdx = 0;
     txIdx = 0;
 
-    /* assign static pointer to BD area */
-    dpaddr = m8260_cpm_dpalloc(sizeof(RTXBD) + 2, 16);
-    rtx = (RTXBD *)&immr->im_dprambase[dpaddr];
+    /*
+     * Assign static pointer to BD area.
+     * Avoid exhausting DPRAM, which would cause a panic.
+     */
+    if (rtx == NULL) {
+	    dpaddr = m8260_cpm_dpalloc(sizeof(RTXBD) + 2, 16);
+	    rtx = (RTXBD *)&immr->im_dprambase[dpaddr];
+    }
 
     /* 24.21 - (1-3): ioports have been set up already */
 
@@ -338,7 +352,7 @@
 }
 
 
-void eth_halt(void)
+static void sec_halt(struct eth_device *dev)
 {
     volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
     immr->im_scc[CONFIG_ETHER_INDEX-1].scc_gsmrl &= ~(SCC_GSMRL_ENR |
@@ -346,7 +360,7 @@
 }
 
 #if 0
-void restart(void)
+static void sec_restart(void)
 {
     volatile immap_t *immr = (immap_t *)CONFIG_SYS_IMMR;
     immr->im_cpm.cp_scc[CONFIG_ETHER_INDEX-1].scc_gsmrl |= (SCC_GSMRL_ENR |
@@ -354,4 +368,20 @@
 }
 #endif
 
-#endif
+int mpc82xx_scc_enet_initialize(bd_t *bis)
+{
+	struct eth_device *dev;
+
+	dev = (struct eth_device *) malloc(sizeof *dev);
+	memset(dev, 0, sizeof *dev);
+
+	sprintf(dev->name, "SCC ETHERNET");
+	dev->init   = sec_init;
+	dev->halt   = sec_halt;
+	dev->send   = sec_send;
+	dev->recv   = sec_rx;
+
+	eth_register(dev);
+
+	return 1;
+}