ARM: socfpga: make sure socfpga_cpu1start_addr is properly flushed

Make sure socfpga_cpu1start_addr is properly flushed from it's cache line so
that secondary cpu's can see it.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Tested-by: Steffen Trumtrar <s.trumtrar@pengutronix.de>
Signed-off-by: Dinh Nguyen <dinguyen@opensource.altera.com>

arch/arm/mach-socfpga/socfpga.c

@@ -23,6 +23,7 @@
 #include <asm/hardware/cache-l2x0.h>
 #include <asm/mach/arch.h>
 #include <asm/mach/map.h>
+#include <asm/cacheflush.h>
 
 #include "core.h"
 
@@ -73,6 +74,10 @@ void __init socfpga_sysmgr_init(void)
 			(u32 *) &socfpga_cpu1start_addr))
 		pr_err("SMP: Need cpu1-start-addr in device tree.\n");
 
+	/* Ensure that socfpga_cpu1start_addr is visible to other CPUs */
+	smp_wmb();
+	sync_cache_w(&socfpga_cpu1start_addr);
+
 	sys_manager_base_addr = of_iomap(np, 0);
 
 	np = of_find_compatible_node(NULL, NULL, "altr,rst-mgr");