[U-Boot] [RFC PATCH 0/4] sunxi: add support for Allwinner V3s

[Icenowy Zheng]

Hello everyone,

As I received my Lichee Pi Zero board (come with Allwinner V3s), I now ported
mainline u-boot to it, as I cannot bear the BSP provided by Allwinner ;-)

Allwinner V3s is a low-end single-core Cortex-A7 SoC, with 64MB integrated
DRAM, originally targeted on cameras.

Its LQFP package and integrated DRAM makes it easily for any amateur to design
and solder a board for it.

This patchset contains 4 patches, they depends on the following patch:

http://lists.denx.de/pipermail/u-boot/2016-December/276960.html

and

http://lists.denx.de/pipermail/u-boot/2016-December/276961.html .

The first patch introduces DDR2 support to the H3-like DRAM controller driver
in the U-Boot, which is the situation the integrated DRAM in V3s meet.

The second patch adds the basic code for V3s support, and introduces the SPL
for it. With this patch, the code can compile, but cannot run.

The third patch introduces a "stub" device tree for V3s and the Lichee Pi Zero
board. As they have now no mainline kernel support, the devicetree is only
written to enable the UART on the chip.

the fourth patch specially changed some memory space settings for U-Boot for
V3s, which made it suitable for the 64MiB integrated DRAM.