Re: [Qemu-devel] [PATCH 1/9] target-ppc: Rename MMCR0/1 contants

[Alexey Kardashevskiy]

On 05/22/2014 02:55 AM, Tom Musta wrote:
> On 5/21/2014 1:20 AM, Alexey Kardashevskiy wrote:
>> MMCR0 and MMCR1 have different numbers for 32 and 64 bit POWERPC.
>> We are going to support 64bit versions too so let's rename 32bit ones
>> to avoid confusion.
>>
>> 604 uses same SPR number for MMCR0 so it is included in this patch too.
> 
> I'm not sure that it is a 32-bit vs. 64-bit thing as much as it is an
> evolution of Performance Monitor from individual Book IVs into the
> ISA.  Saying differently, the SPR number for MMCR0 is now specified
> in the ISA and is the same for 32 and 64 bit implementations
> ... and is also the same for embedded versus server implementations.
> When the 604 came out, the performance monitor was not yet part of
> the ISA.

The kernel has 2 definitions for MMCR0 and 32 vs. 64 is the condition to
choose one or the other. This is not a spec but still something :)

> Other than that ...
> 
> Reviewed-by: Tom Musta <address@hidden>
> 


-- 
Alexey