[PATCH v6 6/9] ARM: vexpress: Motherboard RS1 memory map support

[Pawel Moll]

On Thu, 2012-01-19 at 16:46 +0000, David Vrabel wrote:
> > It does for me:
> > 
> > # zcat /proc/config.gz | grep EARLY_PRINTK
> > CONFIG_EARLY_PRINTK=y
> > # cat /proc/device-tree/motherboard/arm,v2m-memory-map && echo
> > rs1     
> > #
> 
> earlyprintk needs to be on the kernel command line to enable it.
> Without this option it will work fine.

# cat /proc/cmdline
console=ttyAMA0,38400 earlyprintk rootwait root=/dev/mmcblk0p2 mmci.fmax=12000000 debug

I'll investigate the matter to the bottom, though. Your kernel config
would be helpful, thanks!

> It's also a problem when running as a guest under a hypervisor as there
> won't be any stage 2 translation table entries for non-existent peripherals.
> 
> I think there needs to be someway of finding out from the DTB which UART
> to use.

Yess... The DT+earlyprintk problem was discussed several times already,
without any happy resolution so far...

Paweł