===========================
ref: http://wiki.friendlyarm.com/wiki/index.php/NanoPi_M4V2#Hardware_Spec
GPU : Mali-T864 GPU，supports OpenGL ES1.1/2.0/3.0/3.1, OpenCL, DX11, and AFBC
CPU : big.LITTLE，Dual-Core Cortex-A72(up to 2.0GHz) + Quad-Core Cortex-A53(up to 1.5GHz)
VPU(Vision Processing Unit): 4K VP9 and 4K 10bits H265/H264 60fps decoding, Dual VOP, etc
RAM: Dual-Channel 4GB LPDDR4
STORAGE: EMMC: no Onboard eMMC, but has a eMMC socket SD: microSD Slot x 1
USB: four USB 3.0 Type-A ports USB Type-C, Supports USB2.0 OTG and Power input
HDMI: HDMI 2.0a, supports 4K@60Hz，HDCP 1.4/2.2
Ethernet: Native Gigabit Ethernet
Wi-Fi/BT: 802.11a/b/g/n/ac, Bluetooth 4.1, Wi-Fi and Bluetooth combo module, 2x2 MIMO, dual antenna interface
Buttons：one PowerKey, one Recovery Key
Debug: one Debug UART, 4 Pin 2.54mm header, 3V level, 1500000bps
40Pin GPIO Extension ports: 3 X 3V/1.8V I2C, up to 1 x 3V UART, 1 X 3V SPI, 1 x SPDIF_TX, up to 8 x 3V GPIOs 1 x 1.8V 8 channels I2S 24Pin Extension ports: 2 independent native USB 2.0 Host PCIe x2 PWM x1, PowerKey
Others:
PMU: RK808-D PMIC, cooperated with independent DC/DC, enabling DVFS, software power-down, RTC wake-up, system sleep mode
Audio Out: 3.5mm Dual channel headphone jack, or HDMI
Audio In: one microphone input interface
LED: 1 x power LED and 1 x GPIO Controlled LED
RTC Battery: 2 Pin 1.27/1.25mm RTC battery input connector
Power supply: DC 5V/3A
PCB: 8 Layer, 85 mm x 56 mm
Ambient Operating Temperature: -20℃ to 70℃
===========================
cloning: Android 8.1 source:
git clone https://gitlab.com/friendlyelec/rk3399-android-8.1 --depth 1 -b master
Once code is cloned build,
cd rk3399-android-8.1
./build-nanopc-t4.sh -F -M
Now get full git history
git fetch origin master --unshallow
After this we have to get fuse scripts
https://github.com/friendlyarm/sd-fuse_rk3399/blob/master/README.md
Build an sdcard-to-emmc image (eflasher rom)
Enable exFAT file system support on Ubuntu:
sudo apt-get install exfat-fuse exfat-utils
Generate the eflasher raw image
cd sd-fuse_rk3399
wget http://112.124.9.243/dvdfiles/RK3399/images-for-eflasher/emmc-flasher-images.tgz
tar xzf emmc-flasher-images.tgz
Now get a prebuilt android emmc eflasher image,
wget http://112.124.9.243/dvdfiles/RK3399/images-for-eflasher/android-oreo-images.tgz
tar xzf android-oreo-images.tgz
sudo ./mk-emmc-image.sh android8
In out folder we get full image,
out/rk3399-eflasher-android8-20200314.img
Now flash this on a SD card. Use below command for progress,
(sudo pv -n rk3399-eflasher-android8-20200314.img | sudo dd of=/dev/sdd bs=1M ) 2>&1 | dialog --gauge "Running dd command (cloning), please wait..." 10 70 0
Once flashing is 100%, observe sync and dirty pages
sync & watch -d grep -e Dirty: -e Writeback: /proc/meminfo
Login onto your board via a serial terminal and type "eflasher" to proceed
Login: root Password: fa
Now copy your android build that are inside rk3399-android-8.1/rockdev/Image-nanopc_t4 folder and copy it in eflasher SD card. Insert the SD card in device, and boot the device. Run eflasher and now your emmc is updated with your android's source images.
Android build:
build/make/core/build_id.mk
build/make/core/version_defaults.mk
vendor/rockchip/common/gpu/Android.mk
vendor/rockchip/common/gpu/MaliT860.mk
uboot:
u-boot/board/rockchip/rk33xx/rk33xx.c
u-boot/common/cmd_bootrk.c