Hi Taqi,
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Can i boot Linux on AM1808 attached on a custom board NAND flash using Ethernet cable ?
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Ethernet boot is not possible on AM18x but you can load linux image and filesystem through ethernet,
Supported booting types are , SPI , NAND, NOR, SD.
The bootloaders should be laid on any one of the following SD/NAND/NOR/SPi and we can use the ethernet for loading kernel and filesystem.
You can flash bootloaders through serial port.
http://processors.wiki.ti.com/index.php/Serial_Boot_and_Flash_Loading_Utility_for_OMAP-L138