[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: Harry Fearnhamm <Harry.Fearnhamm@arm.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 4 insertions, 1 deletions

diff --git a/arch/arm/mach-realview/realview_eb.c b/arch/arm/mach-realview/realview_eb.c
index d4a586e38d5b..693fb1e396e0 100644
--- a/arch/arm/mach-realview/realview_eb.c
+++ b/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));