rockchip: ringneck_px30: migrate README to doc/board in rST format

This migrates the plaintext README in
board/theobroma-systems/ringneck_px30 to doc/board/theobroma-systems and
while doing so, update the instructions and rewrite it in rST.

Cc: Quentin Schulz <foss+uboot@0leil.net>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Signed-off-by: Quentin Schulz <quentin.schulz@theobroma-systems.com>

2 files changed, 96 insertions, 0 deletions

diff --git a/doc/board/theobroma-systems/index.rst b/doc/board/theobroma-systems/index.rst
index 0720128ad52..b4da2616c37 100644
--- a/doc/board/theobroma-systems/index.rst
+++ b/doc/board/theobroma-systems/index.rst
@@ -8,3 +8,4 @@ Theobroma Systems
 
    jaguar_rk3588
    puma_rk3399
+   ringneck_px30
diff --git a/doc/board/theobroma-systems/ringneck_px30.rst b/doc/board/theobroma-systems/ringneck_px30.rst
new file mode 100644
index 00000000000..c16b9ed17ed
--- /dev/null
+++ b/doc/board/theobroma-systems/ringneck_px30.rst
@@ -0,0 +1,95 @@
+.. SPDX-License-Identifier: GPL-2.0+
+
+PX30-uQ7 Ringneck
+=================
+
+The PX30-uQ7 (Ringneck) SoM is a µQseven-compatible (40mmx70mm, MXM-230
+connector) system-on-module from Theobroma Systems, featuring the Rockchip PX30.
+
+It provides the following feature set:
+
+  * up to 4GB DDR4
+  * up to 128GB on-module eMMC (with 8-bit 1.8V interface)
+  * SD card (on a baseboard) via edge connector
+  * Fast Ethernet with on-module TI DP83825I PHY
+  * MIPI-DSI/LVDS
+  * MIPI-CSI
+  * USB
+
+    - 1x USB 2.0 dual-role
+    - 3x USB 2.0 host
+
+  * on-module companion controller (STM32 Cortex-M0 or ATtiny), implementing:
+
+    - low-power RTC functionality (ISL1208 emulation)
+    - fan controller (AMC6821 emulation)
+    - USB<->CAN bridge controller (STM32 only)
+
+  * on-module Espressif ESP32 for Bluetooth + 2.4GHz WiFi
+  * on-module NXP SE05x Secure Element
+
+Here is the step-by-step to boot to U-Boot on PX30-uQ7 Ringneck from Theobroma
+Systems.
+
+Get the Source and build ATF binary
+-----------------------------------
+
+.. prompt:: bash
+
+   git clone https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git
+   cd trusted-firmware-a
+   make CROSS_COMPILE=aarch64-linux-gnu- PLAT=px30 bl31
+   export BL31=$PWD/build/px30/release/bl31/bl31.elf
+
+Compile the U-Boot
+------------------
+
+.. prompt:: bash
+
+   cd ../u-boot
+   make CROSS_COMPILE=aarch64-linux-gnu- ringneck-px30_defconfig all
+
+This will build ``u-boot-rockchip.bin`` which can be written to an MMC device
+(eMMC or SD card).
+
+Flash the image
+---------------
+
+Copy ``u-boot-rockchip.bin`` to offset 32k for SD/eMMC.
+
+SD-Card
+~~~~~~~
+
+.. prompt:: bash
+
+   dd if=u-boot-rockchip.bin of=/dev/sdX seek=64
+
+.. note::
+
+   Replace ``/dev/sdX`` to match your SD card kernel device.
+
+eMMC
+~~~~
+
+``rkdeveloptool`` allows to flash the on-board eMMC via the USB OTG interface
+with help of the Rockchip loader binary.
+
+To enter the USB flashing mode on Haikou baseboard, remove any SD card, insert a
+micro-USB cable in the ``Q7 USB P1`` connector (P8), move ``SW5`` switch into
+``BIOS Disable`` mode, power cycle or reset the board and move ``SW5`` switch
+back to ``Normal Boot`` mode. A new USB device should have appeared on your PC
+(check with ``lsusb -d 2207:330d``).
+
+To flash U-Boot on the eMMC with ``rkdeveloptool``:
+
+.. prompt:: bash
+
+   git clone https://github.com/rockchip-linux/rkdeveloptool
+   cd rkdeveloptool
+   autoreconf -i && CPPFLAGS=-Wno-format-truncation ./configure && make
+   git clone https://github.com/rockchip-linux/rkbin.git
+   cd rkbin
+   ./tools/boot_merger RKBOOT/PX30MINIALL.ini
+   cd ..
+   ./rkdeveloptool db rkbin/px30_loader_v2.08.135.bin
+   ./rkdeveloptool wl 64 ../u-boot-rockchip.bin