On Wed, Sep 23, 2015 at 03:38:20PM +0800, Ming Lei wrote:

Hi Leif,


On Tue, Sep 8, 2015 at 8:43 PM, Leif Lindholm [off-list ref] wrote:

quoted

Support for configuring bootconsole and console via the ACPI tables
DBG2 (Debug Port Table 2) [1] and SPCR (Serial Port Console Redirection
Table) [2], defined by Microsoft, has been discussed on and off over the
years.

[1] https://msdn.microsoft.com/en-us/library/windows/hardware/dn639131(v=vs.85).aspx
[2] https://msdn.microsoft.com/en-us/library/windows/hardware/dn639132(v=vs.85).aspx

Licensing concerns have prevented this happening in the past, but as of
10 August 2015, these tables have both been released also under OWF 1.0
(http://www.openwebfoundation.org/legal/the-owf-1-0-agreements/owfa-1-0)
which is think is noncontroversially GPL-compatible?

This set is a first attempt at implementing this.

From distribution view, the patchset looks very useful.

I have one simple question, are there other candidates for conveying this kind
of information like what DBG2/SPCR does? Or are DBG2 and SPCR the
offical speficiations to do such things in ARM server industry?

They are mandated in the SBBR spec

Graeme