[U-Boot] AM335x configurations - console output at early stages lost

[Vasili Galka]

Hi Tom,

I’m working on rebasing an old U-Boot branch for our company’s AM335x
based board upon the current U-Boot release (v2015.04). Our branch was
initially based on the v2013.10 release (the ti/am335x/ board was
taken as reference).

After making all the code compile, I discovered there was a change in
the U-Boot initialization sequence, introduced by commit
a6b541b09022acb6f7c2754100ae26bd44eed1d9, that prevents our code from
working:

Prior to the above mentioned commit, the console serial port was
initialized at a very early stage in the armv7/am335x/board.c:s_init()
function (calling preloader_console_init()). Roughly saying, it was
the first thing done by the SPL code. This made quite much sense, as
it enabled all the code afterwards to output status/debugging info to
the console.
Moving the preloader_console_init() call to spl_board_init() caused it
to be run at a very "late" stage (as part of the board_init_r()
function). AFAIU, now all the code that runs till then has no ability
for any console output.
For example, in our particular case, the DDR configuration code (in
sdram_init()) reads the DDR type from an I2C EEPROM. Obviously, if
something goes wrong in this process, we would like to report it to
the console.

I understand there was a good reason for the mentioned commit (the
GD), however, as you see, we have also lost some important
functionality with it. I would appreciate your advice on how to solve
it.

Best regards,
Vasili Galka