atheros: fix reboot on ar2315 devices which do not implement the atheros reference design workaround for the buggy reset logic (e.g. some senao stuff)

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@13556 3c298f89-4303-0410-b956-a3cf2f4a3e73

target/linux/atheros/files/arch/mips/atheros/ar5315/board.c

@@ -21,6 +21,7 @@
 #include <linux/platform_device.h>
 #include <linux/kernel.h>
 #include <linux/reboot.h>
+#include <linux/delay.h>
 #include <asm/bootinfo.h>
 #include <asm/reboot.h>
 #include <asm/time.h>
@@ -279,15 +280,21 @@ static void ar5315_power_off(void)
 
 static void ar5315_restart(char *command)
 {
-	for(;;) {
+	void (*mips_reset_vec)(void) = (void *) 0xbfc00000;
+
 	/* reset the system */
 	sysRegWrite(AR5315_COLD_RESET,AR5317_RESET_SYSTEM);
 
-		/*
-		 * Cold reset does not work on the AR2315/6, use the GPIO reset bits a workaround.
-		 */
+	/* Cold reset does not work on the AR2315/6, use the GPIO reset bits a workaround.
+	 * give it some time to attempt a gpio based hardware reset
+	 * (atheros reference design workaround) */
 	gpio_direction_output(AR5315_RESET_GPIO, 0);
-	}
+	mdelay(100);
+
+	/* Some boards (e.g. Senao EOC-2610) don't implement the reset logic
+	 * workaround. Attempt to jump to the mips reset location -
+	 * the boot loader itself might be able to recover the system */
+	mips_reset_vec();
 }