ARM: VExpress: enable ARMv7 virt support for VExpress A15

To enable hypervisors utilizing the ARMv7 virtualization extension
on the Versatile Express board with the A15 core tile, we add the
required configuration variable.
Also we define the board specific smp_set_cpu_boot_addr() function to
set the start address for secondary cores in the VExpress specific
manner.
There is no need to provide a custom smp_waitloop() function here.

This also serves as an example for what to do when adding support for
new boards.

Signed-off-by: Andre Przywara <andre.przywara@linaro.org>

board/armltd/vexpress/vexpress_common.c

@@ -256,3 +256,18 @@ ulong get_tbclk(void)
 {
 	return (ulong)CONFIG_SYS_HZ;
 }
+
+#if defined(CONFIG_ARMV7_NONSEC) || defined(CONFIG_ARMV7_VIRT)
+/* Setting the address at which secondary cores start from.
+ * Versatile Express uses one address for all cores, so ignore corenr
+ */
+void smp_set_core_boot_addr(unsigned long addr, int corenr)
+{
+	/* The SYSFLAGS register on VExpress needs to be cleared first
+	 * by writing to the next address, since any writes to the address
+	 * at offset 0 will only be ORed in
+	 */
+	writel(~0, CONFIG_SYSFLAGS_ADDR + 4);
+	writel(addr, CONFIG_SYSFLAGS_ADDR);
+}
+#endif

include/configs/vexpress_ca15_tc2.h

@@ -15,4 +15,9 @@
 #include "vexpress_common.h"
 #define CONFIG_BOOTP_VCI_STRING     "U-boot.armv7.vexpress_ca15x2_tc2"
 
+#define CONFIG_SYSFLAGS_ADDR	0x1c010030
+#define CONFIG_SMP_PEN_ADDR	CONFIG_SYSFLAGS_ADDR
+
+#define CONFIG_ARMV7_VIRT
+
 #endif