On Thu, Oct 23, 2014 at 7:31 AM, Kevin Cernekee [off-list ref] wrote:

quoted

I think we'd just have to add a noearlycon option instead if we made
it the default. It's never been the default before, so I don't think
we should change now. There's also an implicit requirement that the
bootloader has configured the uart already. You could easily hang if
the uart has not been setup.

EARLY_PRINTK is enabled by default on MIPS platforms that support it.
I have been using this for years and found it very helpful in
debugging failures in the kernel boot process (especially intermittent
ones).

But for a new platform it is better to use earlycon as earlycon
provides a clean way of reading the UART information out of DT.  My
original bcm3384 (MIPS) port used EARLY_PRINTK but I recently
converted it to earlycon.  The last remaining goal is to get it
enabled by default again.

Hi Rob,

Do you think we should just drop this patch for now, and use these
options to append "earlycon" to the bootloader-supplied command line:

CONFIG_CMDLINE_BOOL=y
CONFIG_CMDLINE="earlycon"
CONFIG_CMDLINE_OVERRIDE=n

If you have other suggestions on how to enable earlycon by default, I
would be happy to help implement them.

Thanks!