Re: [Qemu-devel] [PATCH 2/2] Add phenom CPU descriptor

[Alexander Graf]

On 27.01.2009, at 15:37, Anthony Liguori wrote:

> Alexander Graf wrote:
> > As part of my ongoing effort to make nested SVM useful, I started  
> > working to get
> > VMware ESX run inside KVM.
> >
> > VMware couples itself pretty tightly to the CPUID, so it's a good  
> > idea to emulate
> > a machine that officially supports SVM and should thus exploit the  
> > powers of
> > nested virtualization.
> >
> > This patch adds a Phenom CPU identifier, that resembles a real- 
> > world phenom
> > CPU as closely as possible.
>
> I didn't apply this last time because I dislike the idea of adding  
> oodles of CPU definitions for x86.  The proper thing to do here is  
> to have an fdt based description of CPU model.  That's not to say I  
> won't apply this patch, but I don't like the idea of adding more and  
> more of these things.

I don't think an fdt based machine description is the right place to  
model CPUs. CPU capabilities are tightly coupled to qemu capabilities.  
Looking at coreduo/phenom descriptors as they are now, we are lacking  
quite some features. These might come in later, but I would guess  
machine descriptions should be rather static and user creatable.

So FWIW the fdt should rather contain a pointer to "phenom" CPU  
instead of describing every single CPUID feature.

Though honestly - we only have a "current Intel" and "current  
migratable" CPU, so we're missing a "current AMD" one just to be  
fair ;-). It's also pretty necessary for nested SVM wizardry whenever  
a guest checks which CPU it runs on (opposed to only the SVM bit like  
KVM).

Alex

> Regards,
>
> Anthony Liguori
>
> > Signed-off-by: Alexander Graf <address@hidden>
> > ---
> > target-i386/helper.c |   28 ++++++++++++++++++++++++++++
> > 1 files changed, 28 insertions(+), 0 deletions(-)
> >
> > diff --git a/target-i386/helper.c b/target-i386/helper.c
> > index c2da767..636a02d 100644
> > --- a/target-i386/helper.c
> > +++ b/target-i386/helper.c
> > @@ -137,6 +137,34 @@ static x86_def_t x86_defs[] = {
> >         .model_id = "QEMU Virtual CPU version " QEMU_VERSION,
> >     },
> >     {
> > +        .name = "phenom",
> > +        .level = 5,
> > +        .vendor1 = CPUID_VENDOR_AMD_1,
> > +        .vendor2 = CPUID_VENDOR_AMD_2,
> > +        .vendor3 = CPUID_VENDOR_AMD_3,
> > +        .family = 16,
> > +        .model = 2,
> > +        .stepping = 3,
> > +        /* Missing: CPUID_VME, CPUID_HT */
> > +        .features = PPRO_FEATURES | +            CPUID_MTRR |  
> > CPUID_CLFLUSH | CPUID_MCA |
> > +            CPUID_PSE36,
> > +        /* Missing: CPUID_EXT_CX16, CPUID_EXT_POPCNT */
> > +        .ext_features = CPUID_EXT_SSE3 | CPUID_EXT_MONITOR,
> > +        /* Missing: CPUID_EXT2_PDPE1GB, CPUID_EXT2_RDTSCP */
> > +        .ext2_features = (PPRO_FEATURES & 0x0183F3FF) |  
> > +            CPUID_EXT2_LM | CPUID_EXT2_SYSCALL | CPUID_EXT2_NX |
> > +            CPUID_EXT2_3DNOW | CPUID_EXT2_3DNOWEXT |  
> > CPUID_EXT2_MMXEXT |
> > +            CPUID_EXT2_FFXSR,
> > +        /* Missing: CPUID_EXT3_LAHF_LM, CPUID_EXT3_CMP_LEG,  
> > CPUID_EXT3_EXTAPIC,
> > +                    CPUID_EXT3_CR8LEG, CPUID_EXT3_ABM,  
> > CPUID_EXT3_SSE4A,
> > +                    CPUID_EXT3_MISALIGNSSE,  
> > CPUID_EXT3_3DNOWPREFETCH,
> > +                    CPUID_EXT3_OSVW, CPUID_EXT3_IBS */
> > +        .ext3_features = CPUID_EXT3_SVM,
> > +        .xlevel = 0x8000001A,
> > +        .model_id = "AMD Phenom(tm) 9550 Quad-Core Processor"
> > +    },
> > +    {
> >         .name = "core2duo",
> >         .level = 10,
> >         .family = 6,