# MangoPI MQ Pro Device Trees for Bluetooth and GPIO ### The MQ pro is a single core RISC-V allwinner D1 64bit 1Ghz, 1Gb SBC, in a Pi-Zero form factor. ## This is a guide for enabling bluetooth and using the MangoPi MQ pro's IO capabilities when running Ubuntu 24.04.1 ----------------------------- # (STILL) A WORK IN PROGRESS - Currently being re-written for the 24.04.1 release. `24.04.1` is a LTS+ release from Ubuntu, and should provide 5+ years of updates. As such it makes a good choice for an unattended headless device. Unfortunately there is no Official Ubuntu image for the MQ Pro, but you can use the image for the Lichee RV dock. This has the same SOC as the MQ-Pro, and boots properly. Once the Lichee image is booted you can swap the device tree it uses for the MQ-Pro one. - Vanilla device trees for all current Risc-v platforms are provided as part of the firmware package for each kernel. - This means that the mqpro device tree *is* available, but is not the default installed by `flash-kernel` for the image file we use. - You can reconfigure `flash-kernel` with a different default device tree name in config - This is future proof, each new kernel deliveres a new device tree that will be installed as the kernel is upgraded. - The idea of compiling your own DT is depreciated in favor of the vanilla mqpro devicetree and using gpiod and pinctl to setup devices. ----------------------------- ## Installing Ubuntu There is *no* specific image provided by Ubuntu for the MQ PRO, but they *do* provide an image for the 'Sipeed Lichee RV' which installs and boots on the MQ Pro with almost everything working. - I had issues getting a successful first boot with a cheap SD card, using a brand-name (Kingston) high speed card solved all the issues. - I am also using a high wear resistance card since I want this to run for years in a hard-to-reach location. - EXPAND!!!, notes about hdmi console, usb ethernet adapters, presetup wifi etc. ` The HDMI console with a USB kbd and mouse works well, install `gpm` to get a working mouse in it. Once i had bluetooth working I was able to attach and use a bluetooth kbd+mouse. ### steps: - AT PRESENT: See the raw log at the end of this doc. # My Motivation: My MQ PRO is connected to a Waveshare LORA hat, I want to make it work but the default Nezha device tree conflicts with some of the pins my HAT uses. So I decided to 'fix' this be putting a better device tree on it. ![My Hardware](reference/waveshare_SX1268_LoRa_HAT/overview.jpg) # Device Trees In the install steps above we reconfigure the system to use the correct MangoPI MQ pro device tree instead of the Sipeed Lichee RV one. A device tree is a file that defines the structure of the peripherals attached to, and provided by, the GPIO and internal busses on a SBC. It is used in several places during initial boot to discover storage, console and other devices as needed. Once the linux kernel starts it is used to provision devices such as UART, network, gpu and other hardware. The device tree itself is a source file that is compiled into a binary to be loaded during boot. In this guide we only replace the device tree used by the kernel when Linux is started in the final stages of boot up. We do not need to modify the device tree used by U-Boot, or the kernel init processes, they still use the default (Sipeed Lichee RV) device tree they were compiled against. Because this part of the boot process already works correctly we can avoid the complexity of recompiling anything. ## Roll Your Own Device Tree Hopefully you can do what you need with the default tree, and dynamically create your devices on it via `gpiod` and `pinctl`. But if not; my somewhat limited notes on compiling the tree, plus a script that handles running the C preprocessor on them (needed to get a working binary) are in the [build-trees](./build-trees) folder. # Using the trees ## Enabling Bluetooth After changing to the correct device tree you also need the correct firmware for the bluetooth adapter, a copy of this is in the [files/rtl_bt/](./files/rtl_bt) folder. * Copy the two firmware (`.bin`) files to `/usr/lib/firmware/rtl_bt/` on the MQ PRO. * Install *Bluez* (`sudo apt install bluez`) and reboot, you can then use `bluetoothctl` to configure and connect ## Status LED The onboard (blue) status LED can be controlled via the sys tree: `sudo sh -c "echo 1 > /sys/devices/platform/leds/leds/blue\:status/brightness"` to turn on `sudo sh -c "echo 0 > /sys/devices/platform/leds/leds/blue\:status/brightness"` to turn off You can make it flash as network traffic is seen with: `sudo sh -c "echo phy0rx > /sys/devices/platform/leds/leds/blue\:status/trigger"` You can make this permanent by, as root, copying `tools/mqpro-status-led.service` to `/etc/systemd/system/`, running `systemctl daemon-reload` then `systemctl enable --now mqpro-status-led.service`. Other control options are available, `sudo cat /sys/devices/platform/leds/leds/blue\:status/brightness` shows a list and the current selection. Most do not work or are not very useful; ymmv. ## Using GPIO Providing a full GPIO how-to is beyond the scope of this document, I use GPIOd to do this. But have also used direct pinctl control via the `/sys/class/gpio` tree. There are many tutorials on doing this online that give a better explanation than I can here ## Allwinner D1 GPIO pins The **D1** SOC runs at 3v3, and you must not exceed this on any of the GPIO pins. The drive current is also very limited, a maximum of 4mA on any individual pin, and 6mA total across a bank of pins (eg the 12 pins in the `*PB*` bank combined cannot draw more than 6mA!). Pins are organised into 7 'banks' (*PA*, *PB*, etc to *PG*) of up to 32 pins, but most banks have fewer pins. ## GPIO Pin Muxing The **D1** SOC itself has 88 GPIO pins. In the MQ PRO some of these GPIO pins are wired directly to peripherals on the board (eg SD card, Wifi chip, etc.) but that still leaves many free lines. The board has a 'standard' Raspberry Pi compatible 40 pin GPIO connector; 12 are reserved for Power lines, leaving 28 GPIO pins available for the user. Internally, the **D1** has a number of internal hardware interfaces for different signal types; 6xUART for serial, 2xSPI, 4xI2C(TWI), 3xI2Si/PCM (audio), 8xPWM, and some additional units for USB, HDMI, Audio, and more (see the Data sheet) The **D1** chip has an internal 'pin muxer' to connect pins to signals. Each pin can connect to a (predefined) set of signals, which allows you to map each pin on the GPIO header to multiple possible functions. You can browse the full range of mappings in the Allwinner D1 datasheet, Table 4-3. - A copy of this table is available here: [reference/d1-pins.pdf](reference/d1-pins.pdf)). Additionally all pins are high-impedance by default and can be set to a HIGH or LOW digital output. They can all work as digital inputs, and all have configurable pull-up and pull down resistors, and can generate interrupts. PWM and ADC input capable pins are limited, see the datasheet for more. ### Internal interfaces The MQ Pro uses several of the **D1**s interfaces on-board, specifically: `UART1` is used to connect to the the bluetooth device by default (with flow control) using `PG6`, `PG7`, `PG8` and `PG9`. It can be reconfigured onto GPIO pins if bluetooth is not required. `TWI2` (`I2C2`) can be mapped to the DVP connector (for touchscreen interfaces) via pins `PE12` and `PE13`. `TWI3` (`I2C3`) can be mapped to the DSI/LVDS connector via pins `PE16` and `PE17`; which also appear on the GPIO connector. `SPI0` is mapped to the optional SPI flash chip (not fitted on consumer units), and cannot be mapped to the GPIO connector. ### Pin Mapping EXAMPLE The D1 has 6 internal UARTs, and many pin mappings are possible on the GPIO connector. When creating a device tree you can create any pin mapping that conforms to this: ```text 3v3 -- o o -- 5v UART1-RX PG13 ------ o o -- 5v UART1-TX PG12 ------ o o -- GND UART3-RX PB7 ------ o o ------ PB8 UART0-TX,UART1-TX GND -- o o ------ PB9 UART0-RX,UART1-RX UART1-TX PD21 ------ o o ------ PB5 UART5-RX UART1-RX PD22 ------ o o -- GND UART2-TX,UART0-TX PB0 ------ o o ------ PB1 UART0-RX,UART2-RX 3v3 -- o o ------ PD14 UART3-CTS PD12 ------ o o -- GND UART3-RTS PD13 ------ o o ------ PC1 UART2-RX UART3-RX PD11 ------ o o ------ PD10 UART3-TX GND -- o o ------ PD15 PE17 ------ o o ------ PE16 UART1-RTS PB10 ------ o o -- GND UART1-CTS PB11 ------ o o ------ PC0 UART2-TX PB12 ------ o o -- GND UART3-TX PB6 ------ o o ------ PB2 UART4-TX PD17 ------ o o ------ PB3 UART4-RX GND -- o o ------ PB4 UART5-TX ``` Notes: - `UART0` maps by default to gpio pins 8 and 10 (*PB8* and *PB9*) is the used for the system console by default at boot and you should expect data on it during boot even if you disable it in the device tree as the kernel starts. - `UART1` is normally used by the bluetooth adapter, enabling it here will disable bluetooth. - `UART1` and `UART3` have flow control lines (rts and cts) available - some pins do not map to any UART devices ## References There are reference copies of the MQ PRO schematic and the AllWinner D1 datasheet in the [references](./reference) folder. Online: * https://mangopi.org/mangopi_mqpro * https://linux-sunxi.org/MangoPi_MQ-Pro * https://github.com/boosterl/awesome-mango-pi-mq-pro # RAW INSTALL LOG ## THIS WILL BE FOLDED INTO THE "STEPS" SECTION ABOVE. ```console wget https://cdimage.ubuntu.com/releases/noble/release/ubuntu-24.04.1-preinstalled-server-riscv64+licheerv.img.xz xzcat ubuntu-24.04.1-preinstalled-server-riscv64+licheerv.img.xz | sudo dd bs=8M conv=fsync status=progress of=/dev/mmcblk0 sudo mount /dev/mmcblk1p1 /mnt sudo vi /mnt/etc/cloud/cloud.cfg.d/55_net.cfg ------ new file comments, contents ------- network: version: 2 wifis: wlan0: optional: true access-points: "SSID": password: "PASSWORD" dhcp4: true ----------------- sudo umount /mnt Insert card to MQ Pro and BOOT - serial adapter useful to follow progress - hdmi console after several minutes, appears to freeze but recovers when prompt reached - should come up on network if wifi configured or using a usb ethernet adapter - login on console or via ssh as ubuntu:ubuntu and follow instructions to change password swap to mqpro dtb: ubuntu@ubuntu:~$ sudo vi /etc/flash-kernel/db ---- Append this after the comments ----- Machine: MangoPI MQ pro Kernel-Flavors: any DTB-Id: allwinner/sun20i-d1-mangopi-mq-pro.dtb Boot-Script-Path: /boot/boot.scr U-Boot-Script-Name: bootscr.uboot-generic Required-Packages: u-boot-tools ---------------- ubuntu@ubuntu:~$ sudo vi /etc/flash-kernel/machine --- change to read (one line) --- MangoPI MQ pro --- ubuntu@ubuntu:~$ sudo flash-kernel Using DTB: allwinner/sun20i-d1-mangopi-mq-pro.dtb Installing /lib/firmware/6.8.0-41-generic/device-tree/allwinner/sun20i-d1-mangopi-mq-pro.dtb into /boot/dtbs/6.8.0-41-generic/allwinner/sun20i-d1-mangopi-mq-pro.dtb Taking backup of sun20i-d1-mangopi-mq-pro.dtb. Installing new sun20i-d1-mangopi-mq-pro.dtb. System running in EFI mode, skipping. Reboot again to check the dt is correct before going further.. ... rebooting takes some time on this board ubuntu@ubuntu:~$ sudo reboot wait.. ssh into the machine as ubuntu: sudo cat /proc/device-tree/model - should return 'MangoPi MQ Pro' -- now update sudo su - screen apt update .. let this run, slow on this machine, especially the first run .. will eventually tell you that a lot of packages (149 as of this guide) need updating apt update .. You may see packages 'deferred due to phasing', this is quite normal, an artifact of Ubuntu's build system, and can safely be ignored. .. This may be a good time to have lunch. When this completes reboot again, or finish the BT setup below first, since it also needs a reboot. # BT and Status LED git clone https://github.com/easytarget/MQ-Pro-IO.git # copy Bluetooth firmware to correct folder sudo cp MQ-Pro-IO/files/rtl_bt/* /usr/lib/firmware/rtl_bt/ - install bluez, use bluetoothctl to connect and pair,etc apt install bluez - this will be applied at next reboot # set up a service for the activity light sudo cp MQ-Pro-IO/files/mqpro-status-led.service /etc/systemd/system/ sudo systemctl daemon-reload sudo systemctl enable --now mqpro-status-led.service ```