ARM: uniphier: allow to enable multiple SoCs

Before this commit, the Kconfig menu in mach-uniphier only allowed us
to choose one SoC to be compiled.  Each SoC has its own defconfig file
for the build-test coverage.  Consequently, some defconfig files are
duplicated with only the difference in CONFIG_DEFAULT_DEVICE_TREE and
CONFIG_{SOC_NAME}=y.

Now, most of board-specific parameters have been moved to device trees,
so it makes sense to include init code of multiple SoCs into a single
image as long as the SoCs have similar architecture.  In fact, some
SoCs of UniPhier family are very similar:
 - PH1-LD4 and PH1-sLD8
 - PH1-LD6b and ProXstream2 (will be added in the upcoming commit)

This commit will be helpful to merge some defconfig files for better
maintainability.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/arch/arm/mach-uniphier/boot-mode/boot-mode.c b/arch/arm/mach-uniphier/boot-mode/boot-mode.c
new file mode 100644
index 0000000..71abdef
--- /dev/null
+++ b/arch/arm/mach-uniphier/boot-mode/boot-mode.c
@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <spl.h>
+#include <linux/io.h>
+#include <mach/boot-device.h>
+#include <mach/sbc-regs.h>
+#include <mach/soc_info.h>
+
+u32 spl_boot_device(void)
+{
+	if (boot_is_swapped())
+		return BOOT_DEVICE_NOR;
+
+	switch (uniphier_get_soc_type()) {
+#if defined(CONFIG_ARCH_UNIPHIER_PH1_SLD3)
+	case SOC_UNIPHIER_PH1_SLD3:
+		return ph1_sld3_boot_device();
+#endif
+#if defined(CONFIG_ARCH_UNIPHIER_PH1_LD4) || \
+	defined(CONFIG_ARCH_UNIPHIER_PH1_PRO4) || \
+	defined(CONFIG_ARCH_UNIPHIER_PH1_SLD8)
+	case SOC_UNIPHIER_PH1_LD4:
+	case SOC_UNIPHIER_PH1_PRO4:
+	case SOC_UNIPHIER_PH1_SLD8:
+		return ph1_ld4_boot_device();
+#endif
+	default:
+		return BOOT_DEVICE_NONE;
+	}
+}