Re: [Qemu-devel] Help needed testing on ppc

[BALATON Zoltan]

On Wed, 7 May 2014, Alexander Graf wrote:
> On 05/07/2014 05:31 PM, Tom Musta wrote:
> > On 5/6/2014 6:17 PM, BALATON Zoltan wrote:
> > > On Tue, 6 May 2014, Tom Musta wrote:
> > > > (2) Your patch makes some store instructions compliant with the most 
> > > > recent ISAs but there are many other instructions that are not addressed 
> > > > by the patch.  I think fixing only some will be a future source of 
> > > > confusion.>>
> > Alex:  do you have an opinion on this?  Are you OK with changing masks for 
> > a few stores but not all instructions in general?
>
> I would like to see someone just test all those load/store instructions on 
> old CPUs and see whether they fault. If none faults, we should just be 
> consistent and remove them for all. If say a 750 really only ignores the Rc 
> bit for stwx for some reason we should just model it accordingly.

To get some answers to this and other questions that are still open I've 
made a test program by stripping down yaboot and adding tests to it so 
that it should be possible to run from Open Firmware as a boot loader. It 
can be found here:

http://goliat.eik.bme.hu/~balaton/oftest/

The files there are:
* oftest - an ELF executable that you can put on some device OF can read
        and run it if it were a boot loader ( e.g. 0> boot hd0,0:\oftest )
* oftest.hfs.xz - the same file on an 800k HFS volume that can be put on
        e.g. a USB drive or CD then used as the previous one
* oftest-src.tar.xz - the source

When run from Open Firmware it should print some information about memory 
layout, MSR setting, stack location, BAT registers and test the stwx 
opcode with and without reserved bit which should help us understand 
better the differences between QEMU and real hardware. I could only test 
it on QEMU though.

I'd appreciate if you could run it on real hardware and take a picture of 
the output screen which you upload somewhere and send the URL to that (or 
if you cannot upload you can send the picture but in that case only to me 
not to the list please). If cannot be seen on the picture please also 
include the model of your machine that should appear at the beginning of 
the Open Firmware greeting line.

Regards,
BALATON Zoltan