Re: [Qemu-devel] [RFC PATCH] powerpc: add PVR mask support

[Alexander Graf]

On 15.08.2013, at 07:44, Alexey Kardashevskiy wrote:

> On 08/15/2013 03:21 PM, Alexander Graf wrote:
>> 
>> 
>> Am 15.08.2013 um 05:35 schrieb Alexey Kardashevskiy <address@hidden>:
>> 
>>> IBM POWERPC processors encode PVR as a CPU family in higher 16 bits and
>>> a CPU version in lower 16 bits. Since there is no significant change
>>> in behavior between versions, there is no point to add every single CPU
>>> version in QEMU's CPU list. Also, new CPU versions of already supported
>>> CPU won't break the existing code.
>>> 
>>> This adds a PVR mask support. POWER7, POWER7+ and POWER8 CPUs
>>> definitions converted to use masks.
>> 
>> How does the user select that he wants a v2.3 p7 cpu with this patch?
> 
> Why would he want that? The behaviour would not change because of the
> version - all definitions use the same POWERPC_FAMILY(POWER7) and PVR is
> not virtualized anyway.

Quite frankly I don't know what to say here. Are you trying to play dumb or are 
you just one of those totally sloppy people who don't care about anything 
outside of their own scope of work?

With HV KVM we can not trap PVR, yes. With PR KVM we do trap PVR and we emulate 
it. With TCG we do trap PVR and we emulate it.

> May be (may be) ppc_cpu_class_by_name() needs to be fixed to try to find
> the PPC CPU class with the biggest mask to choose (for example)
> 004a0201/ffffffff rather than more common 004a0000/ffff0000 (if 004a0201 is
> added to the list separately from the common definition for some reason).

I think the class split as Linux has it should work just fine, no?


Alex