Orange Pi 4 (Rockchip 3399)

I bought 2 of these (via AliExpress) back in August of 2020. They have been sitting in a drawer ever since. I was intrigued by them because they have a 6 core big/little setup (with 2 Cortex 72+ cores and 4 Cortex A53 cores).

• Overview
• Orange Pi R1 plus (RK3328)
• Orange Pi 5 (RK3588)
• Serial console
• Reset button
• Boot Android
• Boot Debian
• Debian Boot, console messages
• HDMI and video
• Flashing Debian onto emmc
• Linux kernel (and U-Boot) sources
• U Boot environment setup for Debian
• U Boot setup for network booting
• The on chip boot ROM

Specific topic and detailed discussion

• Bare metal coding
• A history of other bare metal projects
• GCC
• LED's and switches
• Address map
• 64 bit ARM (aarch64)
• ARM execution levels
• The GIC500 (generic interrupt controller)
• How does it boot?
• Bad SD card
• Ctags and U-boot sources
• Serial ports
• Multiple cores
• Building U-Boot
• Patching U-Boot
• Building U-Boot with bl31
• Crypto hardware
• SGRF (secure mode GRF) register documentation
• USB

• ATF (ARM trusted firmware)

Actual software development

• My Github repository for this board

• First basic "hello" demo
• blink the on-board LED
• Add a printf function
• Generate an interrupt
• Make a bootable SD card
• Some really bare metal coding