* Prarit Bhargava [off-list ref] wrote:

The SPCR (Serial Port Console Redirection) Table provides information
about the configuration of serial port.  This information can be used
to configure the early console.

s/about the configuration of serial port
 /about the configuration of the serial port

SPCR support was added for arm64 and is made available across all arches
in this patchset.  The first patch adds a weak per-arch configuration function
and moves the SPCR code into ACPI.  The second patch adds support to x86.

The existing behaviour on arm64 is maintained.  If the SPCR exists the
earlycon and console are automatically configured.

s/arm64
 /ARM64

which is easier to read and it's also the prevalent spelling:

 triton:~/tip> for N in $(git grep -ih arm64 arch/arm64/ | sed 's/[[:punct:]]/ /g'); do echo $N | grep -iw arm64; done | sort | uniq -c
     412 arm64
       1 Arm64
     854 ARM64

The existing default behaviour on x86 is also maintained.  If no console or
earlycon parameter is defined and the SPCR exists , the serial port is not
configured.  If the earlycon parameter is used both the early console
and the console are configured using the data from the SPCR.

s/exists , the
 /exists, the

But, the logic to not use the SPCR looks confusing to me.

The SPCR is only present if the user has explicitly configured a serial console 
for that machine, either in the firmware, or remotely via IPMI, correct? I.e. SPCR 
will not be spuriously present by default on systems that have a serial console 
but the user never expressed any interest for them, right?

If so then we should pick up that serial console configuration and activate it, 
regardless of any kernel boot options!

Thanks,

	Ingo