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

[Programmingkid]

On Feb 11, 2016, at 3:22 AM, Mark Cave-Ayland wrote:

> On 09/02/16 15:05, Alyssa Milburn wrote:
> 
>> On Tue, Feb 09, 2016 at 09:47:57AM -0500, Programmingkid wrote:
>>>> You can assign addresses for serial DMA and even OS 9 will try poking at the
>>>> dbdma controller, so this is just a question of hooking up the qemu side. I
>>>> can try doing this later today if it's useful..
>>> 
>>> It is definitely useful. The ability to run Mac OS 9 in QEMU depends on it.
>> 
>> After a few days spent poking through the startup process in MacsBug, I'm
>> not sure this is true. But I'll hook it up later (if someone else doesn't do
>> it first).
>> 
>>>> Which version of OS X are you using for testing this?
>>> 
>>> Mac OS 10.2.8 is running as the guest. 
>> 
>> Thanks, I'll see if I can go install 10.2 myself later too..
>> 
>>> I don't know if your string would work, but you are right that the first four bytes are just skipped. So it doesn't really matter what they are. 
>> 
>> 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?

It would appear not. At least not for Mac OS X. I don't know about Linux, *BSD, or Mac OS 9.