The primary bootloader stored in the SoC's internal ROM. It initializes the RAM (DDR3/DDR4/LPDDR4) and loads the secondary bootloader.
Check Device Settings: Navigate to Settings > About Phone/Device and look for the Build Number or Kernel Version. sun50iw9p1 firmware
Because "sun50iw9p1" is a generic chip identifier, firmware is usually specific to the brand and model of your device rather than the chip itself. The primary bootloader stored in the SoC's internal ROM