[OpenBIOS] [PATCH] ppc: fix ESCC reg properties

[Programmingkid]

On Feb 6, 2016, at 4:27 AM, Alyssa Milburn wrote:

> On Sat, Feb 06, 2016 at 12:12:38AM -0500, Programmingkid wrote:
>> I did a little research and found out that some of the properties of the escc-legacy's ch-a and ch-b nodes are wrong. 
>> 
>> ftp://ftp.software.ibm.com/rs6000/technology/spec/chrp/inwork/CHRP_IORef_1.0.pdf
>> According to this CHRP specifications, page 246, the escc-legacy node is suppose to have a "ranges" property. This is missing. It is also missing the #size-cells properties. The escc-legacy/ch-a node also looks like it's device_type property should be "legacy" rather than serial. 
> 
> The spec is quite seriously flawed for ESCC (there's an errata which fixes
> some of it, but even then it doesn't seem to match a lot of Apple's hw), so
> I wouldn't trust anything it says, unfortunately. :(
> 
> If you google e.g. "interrupt-controller" "escc" "boot-rom" then you'll find
> a lot of OF dumps from different hardware which seem to use "serial" for the
> device-type.
> 
> The Mac OS 9 bootloader seems to only look for 'ranges' for CardBus, but I
> see that it is there on real hardware (as an empty property?), might be
> worth trying..
> 
> Maybe it might be a good idea to document these things (and how they differ
> between iteratons of Apple's OF properties, and what is/isn't required by
> OS 9), but I'm not sure where/how to do so. Any suggestions?

Your beige g3 has a serial port. The serial port is connected to the escc. If you have Mac OS X or Linux installed on it, what is the output of this command: ls /dev/tty.*

The output of the command on Mac OS X running in QEMU with both the mac99 and g3beige targets is "ls: no match". I think this means Mac OS X could not find the serial port. 

If the serial port is working perfectly, then in theory we should be able to write to the serial console in QEMU from the terminal using something like this: echo "Hello world" > /dev/tty.serialport.

Anyone know what the device file is that is assigned to the serial port on a Macintosh?