uniphier: call uniphier_scp_is_running() only when on-chip STM is supported

uniphier_scp_is_running() reads the UNIPHIER_STMBE2COM register,
but it does not exist on all SoCs.

Do not call this function if the on-chip SCP is not supported.

Change-Id: I7c71ca0735e3a8e095c3f22ba6165f82a2986362
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>

plat/socionext/uniphier/platform.mk

@@ -60,6 +60,7 @@ BL31_SOURCES		+=	drivers/arm/cci/cci.c			\
 				plat/common/plat_gicv3.c		\
 				plat/common/plat_psci_common.c		\
 				$(PLAT_PATH)/uniphier_bl31_setup.c	\
+				$(PLAT_PATH)/uniphier_boot_device.c	\
 				$(PLAT_PATH)/uniphier_cci.c		\
 				$(PLAT_PATH)/uniphier_gicv3.c		\
 				$(PLAT_PATH)/uniphier_psci.c		\

plat/socionext/uniphier/uniphier_psci.c

@@ -6,6 +6,7 @@
 
 #include <arch_helpers.h>
 #include <common/debug.h>
+#include <errno.h>
 #include <lib/mmio.h>
 #include <lib/psci/psci.h>
 
@@ -113,16 +114,26 @@ static const struct plat_psci_ops uniphier_psci_ops = {
 int plat_setup_psci_ops(uintptr_t sec_entrypoint,
 			const struct plat_psci_ops **psci_ops)
 {
-	uniphier_sec_entrypoint = sec_entrypoint;
-	flush_dcache_range((uint64_t)&uniphier_sec_entrypoint,
-			   sizeof(uniphier_sec_entrypoint));
+	unsigned int soc;
+
+	soc = uniphier_get_soc_id();
+	if (soc == UNIPHIER_SOC_UNKNOWN) {
+		ERROR("unsupported SoC\n");
+		return -ENOTSUP;
+	}
 
+	if (uniphier_get_boot_master(soc) == UNIPHIER_BOOT_MASTER_SCP) {
 		uniphier_psci_scp_mode = uniphier_scp_is_running();
 		flush_dcache_range((uint64_t)&uniphier_psci_scp_mode,
 				   sizeof(uniphier_psci_scp_mode));
 
 		if (uniphier_psci_scp_mode)
 			uniphier_scp_open_com();
+	}
+
+	uniphier_sec_entrypoint = sec_entrypoint;
+	flush_dcache_range((uint64_t)&uniphier_sec_entrypoint,
+			   sizeof(uniphier_sec_entrypoint));
 
 	*psci_ops = &uniphier_psci_ops;