[MIPS] Introduce _machine_restart

Handles machine specific functions by using weak functions.

Signed-off-by: Shinya Kuribayashi <skuribay@ruby.dti.ne.jp>

board/incaip/incaip.c

@@ -26,9 +26,15 @@
 #include <asm/addrspace.h>
 #include <asm/inca-ip.h>
 #include <asm/io.h>
+#include <asm/reboot.h>
 
 extern uint incaip_get_cpuclk(void);
 
+void _machine_restart(void)
+{
+	*INCA_IP_WDT_RST_REQ = 0x3f;
+}
+
 static ulong max_sdram_size(void)
 {
 	/* The only supported SDRAM data width is 16bit.

board/purple/purple.c

@@ -29,6 +29,7 @@
 #include <asm/io.h>
 #include <asm/addrspace.h>
 #include <asm/cacheops.h>
+#include <asm/reboot.h>
 
 #include "sconsole.h"
 
@@ -52,6 +53,13 @@ extern int	asc_serial_getc 	(void);
 extern int	asc_serial_tstc 	(void);
 extern void	asc_serial_setbrg 	(void);
 
+void _machine_restart(void)
+{
+	void (*f)(void) = (void *) 0xbfc00000;
+
+	f();
+}
+
 static void sdram_timing_init (ulong size)
 {
 	register uint pass;

board/tb0229/tb0229.c

@@ -12,10 +12,17 @@
 #include <common.h>
 #include <command.h>
 #include <asm/addrspace.h>
-#include <asm/inca-ip.h>
 #include <asm/io.h>
+#include <asm/reboot.h>
 #include <pci.h>
 
+void _machine_restart(void)
+{
+	void (*f)(void) = (void *) 0xbfc00000;
+
+	f();
+}
+
 #if defined(CONFIG_PCI)
 static struct pci_controller hose;