ARM: rmobile: Convert Porter to SPL

Due to size limitations of the MERAM, switch U-Boot to SPL.
The SPL is loaded by the SPI_LOADER into MERAM and then loads
U-Boot proper into DRAM. This way U-Boot can freely grow in
size in DRAM, as there is plenty of it.

Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>
---
NOTE: To update U-Boot, first install u-boot.img to 0x140000 in SPI NOR,
      then use the Minimon to flash u-boot-spl.srec using ls,2,e6304000.
      To generate u-boot-spl.srec, use objcopy:
        arm-linux-gnueabi-objcopy -O srec spl/u-boot-spl u-boot-spl.srec
diff --git a/configs/porter_defconfig b/configs/porter_defconfig
index 38501d0..0fa308b 100644
--- a/configs/porter_defconfig
+++ b/configs/porter_defconfig
@@ -1,12 +1,22 @@
 CONFIG_ARM=y
 CONFIG_ARCH_RMOBILE=y
-CONFIG_SYS_TEXT_BASE=0xE6304000
+CONFIG_SYS_TEXT_BASE=0x50000000
+CONFIG_SPL_GPIO_SUPPORT=y
+CONFIG_SPL_LIBCOMMON_SUPPORT=y
+CONFIG_SPL_LIBGENERIC_SUPPORT=y
 CONFIG_SYS_MALLOC_F_LEN=0x8000
 CONFIG_R8A7791=y
 CONFIG_TARGET_PORTER=y
+CONFIG_SPL_SERIAL_SUPPORT=y
+CONFIG_SPL_SPI_FLASH_SUPPORT=y
+CONFIG_SPL_SPI_SUPPORT=y
 CONFIG_DEFAULT_DEVICE_TREE="r8a7791-porter-u-boot"
 CONFIG_BOOTDELAY=3
 CONFIG_VERSION_VARIABLE=y
+CONFIG_SPL=y
+CONFIG_SPL_BOARD_INIT=y
+CONFIG_SPL_I2C_SUPPORT=y
+CONFIG_SPL_YMODEM_SUPPORT=y
 CONFIG_CMD_BOOTZ=y
 # CONFIG_CMD_IMI is not set
 # CONFIG_CMD_XIMG is not set
@@ -26,8 +36,14 @@
 CONFIG_CMD_EXT4_WRITE=y
 CONFIG_CMD_FAT=y
 CONFIG_OF_CONTROL=y
+CONFIG_SPL_OF_CONTROL=y
+CONFIG_OF_EMBED=y
+CONFIG_OF_SPL_REMOVE_PROPS="interrupts interrupt-parent dma-names dmas power-domains"
 CONFIG_ENV_IS_IN_SPI_FLASH=y
+CONFIG_SPL_DM_SEQ_ALIAS=y
+CONFIG_SPL_OF_TRANSLATE=y
 CONFIG_CLK=y
+CONFIG_SPL_CLK=y
 CONFIG_CLK_RENESAS=y
 CONFIG_DM_GPIO=y
 CONFIG_RCAR_GPIO=y
@@ -44,6 +60,7 @@
 CONFIG_PCI_RCAR_GEN2=y
 CONFIG_PINCTRL=y
 CONFIG_PINCONF=y
+CONFIG_SPL_PINCTRL=y
 CONFIG_PINCTRL_PFC=y
 CONFIG_DM_REGULATOR=y
 CONFIG_DM_REGULATOR_FIXED=y
@@ -55,3 +72,4 @@
 CONFIG_USB_EHCI_HCD=y
 CONFIG_USB_EHCI_PCI=y
 CONFIG_USB_STORAGE=y
+CONFIG_SPL_FRAMEWORK=y