doc: boards: amlogic: add documentation for KII Pro

Add build instructions for the KII Pro set-top box.

Signed-off-by: Ferass El Hafidi <vitali64pmemail@protonmail.com>
Link: https://lore.kernel.org/r/20230507124109.31778-4-vitali64pmemail@protonmail.com
Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
diff --git a/doc/board/amlogic/index.rst b/doc/board/amlogic/index.rst
index 66b581c..46f44bf 100644
--- a/doc/board/amlogic/index.rst
+++ b/doc/board/amlogic/index.rst
@@ -118,6 +118,7 @@
    sei610
    s400
    u200
+   videostrong-kii-pro
    wetek-core2
    wetek-hub
    wetek-play2
diff --git a/doc/board/amlogic/videostrong-kii-pro.rst b/doc/board/amlogic/videostrong-kii-pro.rst
new file mode 100644
index 0000000..1c6adac
--- /dev/null
+++ b/doc/board/amlogic/videostrong-kii-pro.rst
@@ -0,0 +1,112 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+U-Boot for Videostrong KII Pro (S905)
+=====================================
+
+Videostrong KII Pro is an Android STB manufactured by Videostrong and 
+based on the Amlogic p201 reference board, with the following specification:
+
+ - Amlogic S905 ARM Cortex-A53 quad-core SoC @ 1.5GHz
+ - ARM Mali 450 GPU
+ - 2GB DDR3 SDRAM
+ - 16GB eMMC
+ - Gigabit Ethernet
+ - Boardcom BCM4335 WiFi and BT 4.0
+ - HDMI 2.0 4K/60Hz display
+ - 3x USB 2.0 host
+ - 1x USB 2.0 otg
+ - microSD
+ - Infrared receiver
+ - Blue LED
+ - Red LED
+ - Power button (case, front)
+ - Reset button (underside)
+ - DVB Card: DVB-S and DVB-T/C
+
+Schematics are not publicly available.
+
+U-Boot Compilation
+------------------
+
+.. code-block:: bash
+
+    $ export CROSS_COMPILE=aarch64-none-elf-
+    $ make videostrong-kii-pro_defconfig
+    $ make
+
+U-Boot Signing with Pre-Built FIP repo
+--------------------------------------
+
+.. code-block:: bash
+
+    $ git clone https://github.com/LibreELEC/amlogic-boot-fip --depth=1
+    $ cd amlogic-boot-fip
+    $ mkdir my-output-dir
+    $ ./build-fip.sh wetek-play2 /path/to/u-boot/u-boot.bin my-output-dir
+
+U-Boot Manual Signing
+---------------------
+
+Amlogic does not provide sources for the firmware and tools needed to create 
+a bootloader image and Videostrong has not publicly shared the U-Boot sources 
+needed to build FIP binaries for signing. However you can use the WeTek 
+Play2 binaries from the amlogic-boot-fip repo as the WeTek Play2 and the 
+Videostrong KII Pro share the same RAM chips.
+
+.. code-block:: bash
+
+    $ git clone https://github.com/LibreELEC/amlogic-boot-fip --depth=1
+    $ cd amlogic-boot-fip/wetek-play2
+    $ export FIPDIR=$PWD
+
+Go back to the mainline U-Boot source tree then:
+
+.. code-block:: bash
+
+    $ mkdir fip
+    $ cp $FIPDIR/bl2.bin fip/
+    $ cp $FIPDIR/acs.bin fip/
+    $ cp $FIPDIR/bl21.bin fip/
+    $ cp $FIPDIR/bl30.bin fip/
+    $ cp $FIPDIR/bl301.bin fip/
+    $ cp $FIPDIR/bl31.img fip/
+    $ cp u-boot.bin fip/bl33.bin
+    $ $FIPDIR/blx_fix.sh \
+              fip/bl30.bin \
+              fip/zero_tmp \
+              fip/bl30_zero.bin \
+              fip/bl301.bin \
+              fip/bl301_zero.bin \
+              fip/bl30_new.bin \
+              bl30
+    $ $FIPDIR/fip_create --bl30 fip/bl30_new.bin \
+                         --bl31 fip/bl31.img \
+                         --bl33 fip/bl33.bin \
+                         fip/fip.bin
+    $ sed -i 's/\x73\x02\x08\x91/\x1F\x20\x03\xD5/' fip/bl2.bin
+    $ python3 $FIPDIR/acs_tool.py fip/bl2.bin fip/bl2_acs.bin fip/acs.bin 0
+    $ $FIPDIR/blx_fix.sh \
+              fip/bl2_acs.bin \
+              fip/zero_tmp \
+              fip/bl2_zero.bin \
+              fip/bl21.bin \
+              fip/bl21_zero.bin \
+              fip/bl2_new.bin \
+              bl2
+    $ cat fip/bl2_new.bin fip/fip.bin > fip/boot_new.bin
+    $ $FIPDIR/aml_encrypt_gxb --bootsig \
+                              --input fip/boot_new.bin
+                              --output fip/u-boot.bin
+
+Then write U-Boot to SD or eMMC with:
+
+.. code-block:: bash
+
+    $ DEV=/dev/boot_device
+    $ dd if=fip/u-boot.bin of=fip/u-boot.bin.gxbb bs=512 conv=fsync
+    $ dd if=fip/u-boot.bin of=fip/u-boot.bin.gxbb bs=512 seek=9 skip=8 count=87 conv=fsync,notrunc
+    $ dd if=/dev/zero of=fip/u-boot.bin.gxbb bs=512 seek=8 count=1 conv=fsync,notrunc
+    $ dd if=bl1.bin.hardkernel of=fip/u-boot.bin.gxbb bs=512 seek=2 skip=2 count=1 conv=fsync,notrunc
+    $ ./aml_chksum fip/u-boot.bin.gxbb
+    $ dd if=fip/u-boot.bin.gxbb of=$DEV conv=fsync,notrunc bs=512 skip=1 seek=1
+    $ dd if=fip/u-boot.bin.gxbb of=$DEV conv=fsync,notrunc bs=1 count=440