SpacemiT K1 OpenWrt SDK: Complete Development Guide

From SDK download to custom firmware build — the complete guide to developing OpenWrt on the K1 RISC-V platform.

K1OpenWrtSDKRISC-VRouter

Overview

The SpacemiT K1 is an 8-core RISC-V SoC (X60 @1.6GHz) with native OpenWrt 23.05 support. This guide walks through the complete development workflow: obtaining the SDK, building firmware, flashing, and developing custom packages.

Prerequisites

Ubuntu 22.04 or later (or WSL2 on Windows)
At least 16GB RAM, 50GB free disk
Git, build-essential, common build tools
K1 development board (BPI-F3 or MUSE-Pi)
USB-TTL adapter for serial console

1. Obtain the SDK

The OpenWrt SDK for K1 is hosted on Gitee:

git clone https://gitee.com/bianbu-linux/openwrt.git
cd openwrt
git checkout bl-v2.0.y

The SDK includes:

OpenSBI (supervisor binary interface)
U-Boot (bootloader with UEFI support)
Linux Kernel 6.1 (with K1 BSP patches)
OpenWrt rootfs with middleware
AI support (onnxruntime with hardware acceleration)
MPP (Media Process Platform)
FFmpeg/GStreamer with hardware acceleration

2. Build Environment Setup

sudo apt update
sudo apt install -y build-essential clang flex bison g++ gawk   gcc-multilib g++-multilib gettext git libncurses-dev libssl-dev   python3-distutils rsync unzip zlib1g-dev

cd openwrt
./scripts/feeds update -a
./scripts/feeds install -a

3. Configure for K1

make menuconfig

Select:

Target: SpacemiT
Subtarget: K1
Profile: BPI-F3 or MUSE-Pi
Packages: Select desired packages (mwan3, iptables, tc, etc.)

4. Build Firmware

make -j$(nproc) V=s

First build takes 1-2 hours. Output files are in bin/targets/spacemit/.

5. Flash Firmware

Connect USB-TTL to the board's debug UART (115200 8N1). Power on, press any key in serial console to enter U-Boot:

# TFTP flash method
setenv serverip 192.168.1.100
setenv ipaddr 192.168.1.200
tftpboot 0x90000000 openwrt-spacemit-k1-sbc-debX-ext4-pack.zip
# Or use USB/DOS methods

6. Pre-built Firmware

If you just want to test, pre-built firmware is available:

7. Supported Hardware

BPI-F3 (Banana Pi F3)
MUSE-Pi (SpacemiT official dev board)

8. Key Features

CPU	8x X60 RISC-V @1.6GHz (50K DMIPS)
GPU	PowerVR BXE-2-32 (2D/3D acceleration)
AI	2.0 TOPS (INT8) via custom RISC-V instructions
Memory	LPDDR4X up to 16GB
Network	2x GMAC, 5x PCIe, 12x UART, 2x CAN-FD
OS	OpenWrt 23.05, Bianbu Linux (Ubuntu-based), OpenHarmony