sunxi: add PineCube board

PineCube is an IP camera development kit released by Pine64.

It comes with the following compoents:

- A mainboard with Sochip S3 SoC, a 16MByte SPI Flash, AXP209 PMIC,
a power-only microUSB connector, a USB Type-A connector, a 10/100Mbps
Ethernet port and FPC connectors for camera and daughter board.
- An OV5640-based camera module which is connected to the parallel CSI
bus of the mainboard.
- A daughterboard with several buttons, a SD slot, some IR LEDs, a
microphone and a speaker connector.

As the device tree is synchronized in a previous commit, just add it to
Makefile, create a new MAINTAINER item and provide a defconfig.

Signed-off-by: Icenowy Zheng <icenowy@aosc.io>
Reviewed-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

arch/arm/dts/Makefile

@@ -590,6 +590,7 @@ dtb-$(CONFIG_MACH_SUN8I_R40) += \
 	sun8i-r40-bananapi-m2-ultra.dtb \
 	sun8i-v40-bananapi-m2-berry.dtb
 dtb-$(CONFIG_MACH_SUN8I_V3S) += \
+	sun8i-s3-pinecube.dtb \
 	sun8i-v3s-licheepi-zero.dtb
 dtb-$(CONFIG_MACH_SUN50I_H5) += \
 	sun50i-h5-bananapi-m2-plus.dtb \

board/sunxi/MAINTAINERS

@@ -440,6 +440,11 @@ M:	Vasily Khoruzhick <anarsoul@gmail.com>
 S:	Maintained
 F:	configs/pinebook_defconfig
 
+PINECUBE BOARD:
+M:	Icenowy Zheng <icenowy@aosc.io>
+S:	Maintained
+F:	configs/pinecube_defconfig
+
 PINE64 BOARDS
 M:	Andre Przywara <andre.przywara@arm.com>
 S:	Maintained

configs/pinecube_defconfig

@@ -0,0 +1,15 @@
+CONFIG_ARM=y
+CONFIG_ARCH_SUNXI=y
+CONFIG_SPL=y
+CONFIG_MACH_SUN8I_V3S=y
+CONFIG_SUNXI_DRAM_DDR3_1333=y
+CONFIG_DRAM_CLK=504
+CONFIG_DRAM_ODT_EN=y
+CONFIG_I2C0_ENABLE=y
+CONFIG_DEFAULT_DEVICE_TREE="sun8i-s3-pinecube"
+CONFIG_SPL_I2C_SUPPORT=y
+# CONFIG_NETDEVICES is not set
+CONFIG_AXP209_POWER=y
+CONFIG_AXP_DCDC2_VOLT=1250
+CONFIG_AXP_DCDC3_VOLT=3300
+CONFIG_CONS_INDEX=3