[ARM] 3527/1: MPCore Boot Lockup Fix

Patch from Harry Fearnhamm

This patch fixes the occasional lockup seen in early boot stage
on RealView MPCore system.
Signed-off-by: NHarry Fearnhamm <Harry.Fearnhamm@arm.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-realview/realview_eb.c

@@ -137,8 +137,11 @@ static struct amba_device *amba_devs[] __initdata = {
 static void __init gic_init_irq(void)
 {
 #ifdef CONFIG_REALVIEW_MPCORE
+	unsigned int pldctrl;
 	writel(0x0000a05f, __io_address(REALVIEW_SYS_LOCK));
-	writel(0x008003c0, __io_address(REALVIEW_SYS_BASE) + 0xd8);
+	pldctrl = readl(__io_address(REALVIEW_SYS_BASE)	+ 0xd8);
+	pldctrl |= 0x00800000;	/* New irq mode */
+	writel(pldctrl, __io_address(REALVIEW_SYS_BASE) + 0xd8);
 	writel(0x00000000, __io_address(REALVIEW_SYS_LOCK));
 #endif
 	gic_dist_init(__io_address(REALVIEW_GIC_DIST_BASE));