Early prints on different UART's for same machine type

["Mohammed, Afzal" <afzal@ti.com>]

Hi,

This is regarding board with multiple variations using an upcoming SoC from TI.
Variation of the board is detected by reading EEPROM using I2C after
init_machine gets invoked. In one of the variation UART# used is different.
Because of this decompressor logs (and early prints) can't be captured for the
board variant using this different UART#. Our solution for this problem is to
use different mach-id for the board using different UART#. But this solution
seems to be overkill as only to capture decompressor logs, we have to use
a new machine id.

As I2C will not work at the decompressor stage, I2C can't be used to detect
the board type.

As far as I know, ATAG is not parsed in decompressor stage and so ATAG cannot
be used to determine board variant or UART#. Otherwise we will have to add
capability in decompressor to parse ATAG, detect console to be used, and
modify uncompress.h to select proper console for capturing decompressor logs.
This seems a bad solution.

Our bootloader has the capability to detect the board variant.

So the best solution for us so far seems to add a new machine id, if any
better solutions are possible, please let us know.

Regards
Afzal