If AQR113C has no external spi flash. How to configure

We designed our own motherboard with Orin module, and we used AQR113C phy chip. I found that there is an external SPI FLASH on the orin development board, and what is stored in it. If I remove the spi flash, can AQR113C work normally? I read the following paragraph in the AQR113C manual:

The image for the microcontroller is stored either in an optional external SPI FLASH or loaded at boot time via the MDIO interface (MDIO boot-load)

It seems that SPI FLASH stores the firmware of this microcontroller. I found the chip driver code of AQR113C in jp5.0.2, but I did not find that the firmware was loaded through the MDIO interface. The motherboard we designed also has an external spi flash. Do we need to burn the firmware into this SPI FLASH?

Please consult with vendor to get the firmware and tools due to license issue we don’t allow to public them here.

How does the orin development board burn the firmware into the spi flash? Is it burned before welding to the board? We need to burn the firmware onto our own board, please help me

Sorry that we are not able to provide the method to flash eth phy here. This is also not what we support.