MIPS: AR7: register watchdog device only if enabled in hw configuration

This patch checks if the watchdog enable bit is set in the DCL register
meaning that the hardware watchdog actually works and if so, register the
ar7_wdt platform_device.

Signed-off-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
diff --git a/arch/mips/ar7/platform.c b/arch/mips/ar7/platform.c
index e2278c0..835f3f0 100644
--- a/arch/mips/ar7/platform.c
+++ b/arch/mips/ar7/platform.c
@@ -503,6 +503,7 @@
 {
 	u16 chip_id;
 	int res;
+	u32 *bootcr, val;
 #ifdef CONFIG_SERIAL_8250
 	static struct uart_port uart_port[2];
 
@@ -595,7 +596,13 @@
 
 	ar7_wdt_res.end = ar7_wdt_res.start + 0x20;
 
-	res = platform_device_register(&ar7_wdt);
+	bootcr = (u32 *)ioremap_nocache(AR7_REGS_DCL, 4);
+	val = *bootcr;
+	iounmap(bootcr);
+
+	/* Register watchdog only if enabled in hardware */
+	if (val & AR7_WDT_HW_ENA)
+		res = platform_device_register(&ar7_wdt);
 
 	return res;
 }