Re: [Qemu-devel] [PATCH] Make rtl8139 network interface card compatible with Mac OS 10.4

[Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>]

On 02/01/16 17:08, Programmingkid wrote:

>> After some head scratching chasing this through for several hours
>> yesterday, I've worked out what is happening and have a patchset for
>> OpenBIOS which should fix the issue (will post later along with some
>> other PCI fixes for testing).
>>
>> This is actually a bug in Darwin in that it doesn't parse the address
>> space part of the "ranges" property for the /pci node. OpenBIOS adds all
>> 3 spaces to the "ranges" - configuration, I/O and memory compared to
>> real Macs which only add I/O and memory. Which is generally fine because
>> each entry contains a 2-bit indicator so that the OS knows which entry
>> represents each address space.
>>
>> Except that Darwin evidently doesn't bother parsing the address space
>> from each "range" entry and blindly assumes that entry 0 is I/O space
>> and entry 1 is memory space as would be found in a real Mac device tree.
>> The result of this is that currently I/O accesses go to entry 0 (config
>> space) and memory accesses go to entry 1 (I/O space) which is why the
>> RTL8139 happens to work with your patch to force bus mastering.
>>
>> AFAICT with basic testing here, forcing the /pci node to mimic that of a
>> real Mac by omitting the configuration space entry seems to fix all PCI
>> accesses (or at least they get routed to the correct address spaces), I
>> see an attempt to set the bus master bit in the command register, and I
>> don't get a reset timeout on startup for the RTL8139 anymore.
> 
> 
> Wow, you figure out stuff fast! Will be waiting for your patches.

I've just posted the OpenBIOS patches to the list (see
http://www.openfirmware.info/pipermail/openbios/2016-January/008959.html).
Please test and let me know if this solves your networking problems
against a vanilla QEMU git master checkout - it looks good in the logs,
but I can't quite figure out how to manually bring up a new en0
interface in Darwin from the command line.


ATB,

Mark.