ARM: uniphier: add eMMC boot support

Export device nodes needed for eMMC boot (eMMC node, pinctrl, and
clock) to the SPL DTB.  CONFIG_SUPPORT_EMMC_BOOT is also necessary
to use "mmc partconf" command.

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
index 935e551..2f2e45d 100644
--- a/arch/arm/mach-uniphier/boot-mode/boot-mode.c
+++ b/arch/arm/mach-uniphier/boot-mode/boot-mode.c
@@ -5,6 +5,7 @@
  */
 
 #include <common.h>
+#include <mmc.h>
 #include <spl.h>
 
 #include "../sbc/sbc-regs.h"
@@ -52,3 +53,27 @@
 
 	return ret == BOOT_DEVICE_USB ? BOOT_DEVICE_NOR : ret;
 }
+
+u32 spl_boot_mode(void)
+{
+	struct mmc *mmc;
+
+	/*
+	 * work around a bug in the Boot ROM of PH1-sLD3, LD4, Pro4, and sLD8:
+	 *
+	 * The boot ROM in these SoCs breaks the PARTITION_CONFIG [179] of
+	 * Extended CSD register; when switching to the Boot Partition 1, the
+	 * Boot ROM should issue the SWITCH command (CMD6) with Set Bits for
+	 * the Access Bits, but in fact it uses Write Byte for the Access Bits.
+	 * As a result, the BOOT_PARTITION_ENABLE field of the PARTITION_CONFIG
+	 * is lost.  This bug was fixed for PH1-Pro5 and later SoCs.
+	 *
+	 * Fixup mmc->part_config here because it is used to determine the
+	 * partition which the U-Boot image is read from.
+	 */
+	mmc = find_mmc_device(0);
+	mmc->part_config &= ~EXT_CSD_BOOT_PART_NUM(PART_ACCESS_MASK);
+	mmc->part_config |= EXT_CSD_BOOT_PARTITION_ENABLE;
+
+	return MMCSD_MODE_EMMCBOOT;
+}