| BeagleV |
| ======= |
| |
| BeagleV is a low-cost RISC-V 64-bit based platform, powered by a |
| Starfive JH7100 processor. The current defconfig in Buildroot has been |
| tested with the JH7100 chip used on the beta version of the BeagleV |
| board. |
| |
| How to build |
| ============ |
| |
| $ make beaglev_defconfig |
| $ make |
| |
| Build results |
| ============= |
| |
| After building, output/images contains: |
| |
| + bootloader-BEAGLEV-buildroot.bin.out |
| + ddrinit-2133-buildroot.bin.out |
| + Image |
| + fw_payload.bin |
| + fw_payload.bin.out |
| + fw_payload.elf |
| + rootfs.ext2 |
| + rootfs.ext4 |
| + sdcard.img |
| + u-boot.bin |
| |
| The four important files are: |
| |
| - bootloader-BEAGLEV-buildroot.bin.out, the first stage bootloader |
| |
| - ddrinit-2133-buildroot.bin.out, the DDR initialization firmware |
| |
| - fw_payload.bin.out, which is the bootloader image, containing |
| both OpenSBI and U-Boot. |
| |
| - sdcard.img, the SD card image, which contains the root filesystem, |
| kernel image and Device Tree. |
| |
| Flashing the SD card image |
| ========================== |
| |
| $ sudo dd if=output/images/sdcard.img of=/dev/sdX |
| |
| Preparing the board |
| =================== |
| |
| Connect the Beagle-V fan to the 5V supply (pin 2 or 4 of the GPIO |
| connector) and GND (pin 6 of the GPIO connector). |
| |
| Connect a TTL UART cable to pin 8 (TX), 10 (RX) and 14 (GND). |
| |
| Insert your SD card. |
| |
| Power-up the board using an USB-C cable. |
| |
| Flashing OpenSBI/U-Boot |
| ======================= |
| |
| The bootloader pre-flashed on the Beagle-V has a non-working |
| fdt_addr_r environment variable value, so it won't work |
| as-is. Reflashing the bootloader with the bootloader image produced by |
| Buildroot is necessary. |
| |
| When the board starts up, a pre-loader shows a count down of 2 |
| seconds, interrupt by pressing any key. You should reach a menu like |
| this: |
| |
| --------8<---------- |
| |
| bootloader version:210209-4547a8d |
| ddr 0x00000000, 1M test |
| ddr 0x00100000, 2M test |
| DDR clk 2133M,Version: 210302-5aea32f |
| 0 |
| *************************************************** |
| *************** FLASH PROGRAMMING ***************** |
| *************************************************** |
| |
| 0:update uboot |
| 1:quit |
| select the function: |
| |
| --------8<---------- |
| |
| Press 0 and Enter. You will now see "C" characters being |
| displayed. Ask your serial port communication program to send |
| fw_payload.bin.out using the Xmodem protocol. |
| |
| After reflashing is complete, restart the board, it will automatically |
| start the system from the SD card, and reach the login prompt. |
| |
| Flashing low-level bootloaders |
| ============================== |
| |
| The BeagleV comes pre-flashed with functional low-level bootloaders |
| (called "secondboot" and "ddrinit"). Re-flashing them is not necessary |
| to use this Buildroot defconfig. However, for the sake of |
| completeness, Buildroot builds and provides those low-level bootloader |
| images. |
| |
| You can flash them as follows: |
| |
| - In the same "pre-loader" menu as the one used above, instead of |
| entering 0 or 1, enter the magic "root@s5t" string. This enters the |
| "expert" features. |
| |
| - Then, press 0 and send over X-modem the |
| bootloader-BEAGLEV-buildroot.bin.out file. |
| |
| - Then, press 1 and send over X-modem the |
| ddrinit-2133-buildroot.bin.out. |
| |
| Note that the reflashing mechanism itself relies on those low-level |
| bootloaders, so if you flash non-working versions, you'll have to go |
| through a recovery process. This requires wiring up to a separate |
| debug UART, which pins are located near the HDMI connector. See |
| https://wiki.seeedstudio.com/BeagleV-Update-bootloader-ddr-init-boot-uboot-Recover-bootloader/ |
| section "Recover the bootloader" for more details. |
