I got three pieces of those RockPi 4 v1.4B 4GB. I didn’t order a SPI flash built-in, but I received with this EEPROM chip on board. Now the problem is to have a SPI1 device, since the CS0 is already occupied by flash IC. I am searching to solve the problem by simply using a GPIO for CS1 , but unfortunately the RK3399 doesn’t support cs-gpios in the main linux kernel.
Is there any solution, there are also some custom patches for Linux system to add a cs-gpios, but isn’t up to Rockchip to make a version of their devices to add support for cs-gpios?
I understand, but I don’t want to unsolder the EEPROM, because I am afraid I will burn the board. RK3399 has only one CS for each SPI bus - correct. As many other boards, the GPIO is used as second, third,…CS aka cs-gpios. As said, you could contact Rockchip to change their kernel driver to support this, there are also user patches, but all different and not merged into mainline kernel.
I am a noob in this world, just learning. The patch comes from member of yours team, I guess: martinayotte . I don’t know if it’s a good idea to upload a patch on his behalf due to the intellectual property.
Ask him, but IMHO if you edit patches and send them under your name + adding a reference or claiming co-authorship its perfectly fine. Lots of patches came from the wilderness where we actually don’t know who is the author without high end forensics Its might be his work or not. I don’t know …
It seems that I am struggling with the same problem. I have a v1.6 Board and as it seems I cannot use the spidev on the bus 1 because it is used by the SPI Flash
Is there a non-hardware changing solution to disabling the SPI Flash?
And in case there is none, would the de-soldering affect me in any other way besides not being able to boot from SPI?
Thank you in advance for your help!
Regards,
Artur
And in case there is none, would the de-soldering affect me in any other way besides not being able to boot from SPI?
Yes, the SPI flash did not store anything except the bootloader, you can also put bootloader on SD card or eMMC. The SPI flash is only useful when user want to boot form NVMe/USB without SD card or eMMC.
It seems to me redundant to have both a soldered SPI Flash, and a eMMC. I am using the bootloader on the eMMC and the OS is flashed on the NVMe, it is working flawlessly.
Still asking myself if the SPI Flash can be somehow disabled on boot.
Anyway, too late for me to investigate this.
The individual users and the project users have different requirements. If you are an early user in this forum, you will find many users want to boot off NVMe SSD directly, which requires the SPI flash.