[OpenBIOS] [PATCH] drivers/escc.c: Add slot-names property ch-a node under escc

[BALATON Zoltan]

On Thu, 11 Feb 2016, Mark Cave-Ayland wrote:
> On 09/02/16 15:05, Alyssa Milburn wrote:
>> The first four bytes are the slot bitmask (as a 32-bit BE integer), followed
>> by one string per slot (so, one string for each set bit). I don't know
>> whether any OS cares about this or not, another thing to look into..
>
> Is the bitmask used to indicate the port presence? If so, could we get
> away with just setting it to zero, i.e. there are no ports here so don't
> try and access them? Other than that, do OSs check for specific values
> of the name string?

That's what I was suggesting too and this device tree seems to support 
this (it has slot-names property with just 00000000 for both channels):

http://nandra.segv.jp/NetBSD/G4.dump-device-tree.txt

Setting the property to indicate we have a modem connected which we don't 
emulate may be looking for trouble if the OS is trying to access that but 
I'm not sure if Mac OS looks at the property or just assumes what's on 
the real machine. It may still look for external modems and use DMA to do 
serial transfers though.

Regards,
BALATON Zoltan