Commit Graph

8 Commits

Author SHA1 Message Date
Eduardo Habkost
c34ea31416 add SandyBridge CPU model
This patches add the definition of a SandyBridge CPU model.

Summary of differences:

Flags present on actual hardware, but not on the added model definition:

- pbe, tm, ht, ss, acpi, vme, xTPR, tm2, eist, smx: host-specific
  features, not exposed to guest.
- ds, ds-cpl, dtes64, pdcm: emulation not supported by KVM (although it
  may be added in the future if implementing PMU virtualization)
- pcid, vmx, monitor: not emulated by Qemu/KVM right now.
- osxsave: set by the guest OS, not by Qemu.

Flags added, that were not present on Westmere model:

- xsave: already supported by Qemu
- avx, pclmulqdq: all new state the new instructions could use is
  handled by xsave state loading/saving code.
- tsc-deadline, x2apic, rdtscp: already supported by Qemu/KVM.

Below there's a comparison of the features on the current Westmere CPU
model, and the SandyBridge CPU model.

- The "full" line contains the flags found on actual hardware.
- The "missing" line shows the flags that are present on actual
  hardware, but not on the added SandyBridge model.
- The "new" line shows the flags that were not on the Westmere model,
  but are on SandyBridge.

feature_edx:
  Westmere:                 sse2 sse fxsr mmx         clflush pse36 pat cmov mca pge mtrr sep apic cx8 mce pae msr tsc pse de     fpu
  full:        pbe tm ht ss sse2 sse fxsr mmx ds acpi clflush pse36 pat cmov mca pge mtrr sep apic cx8 mce pge msr tsc pse de vme fpu
  SandyBridge:              sse2 sse fxsr mmx         clflush pse36 pat cmov mca pge mtrr sep apic cx8 mce pae msr tsc pse de     fpu
  missing:     pbe tm ht ss                   ds acpi                                                                         vme

feature_ecx:
  Westmere:                      aes              popcnt        sse4.2 sse4.1                cx16 ssse3                                                  sse3
  full:        avx osxsave xsave aes tsc-deadline popcnt x2apic sse4.2 sse4.1 pcid pdcm xTPR cx16 ssse3 tm2 eist smx vmx ds-cpl monitor dtes64 pclmulqdq sse3
  SandyBridge: avx         xsave aes tsc-deadline popcnt x2apic sse4.2 sse4.1                cx16 ssse3                                        pclmulqdq sse3
  missing:         osxsave                                                    pcid pdcm xTPR            tm2 eist smx vmx ds-cpl monitor dtes64
  new:         avx         xsave     tsc-deadline        x2apic                                                                                pclmulqdq

extfeature_edx:
  Westmere:    i64        nx syscall
  full:        i64 rdtscp nx syscall
  SandyBridge: i64 rdtscp nx syscall
  new:             rdtscp

extfeature_ecx:
  Westmere:    lahf_lm
  full:        lahf_lm
  SandyBridge: lahf_lm

Cc: "Dugger, Donald D" <donald.d.dugger@intel.com>
Cc: "Zhang, Xiantao" <xiantao.zhang@intel.com>
Acked-by: Xiantao Zhang <xiantao.zhang@intel.com>
Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-03-12 14:05:25 -05:00
Eduardo Habkost
adbbdf2484 cpu defs: uncomment empty extfeatures_ecx definition for Opteron_G1 (v2)
This should have no visible effect, but it should just clean up the
config file a bit.

This is based on a previous patch from John Cooper where this was introduced
with many other changes at the same time. Original John's patch submission is
at Message-ID: <4DDAD5E7.2020002@redhat.com>, <http://marc.info/?l=qemu-devel&m=130618871926030>.

Changes v1 -> v2:
 - Rebase against latest Qemu git tree

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-02-22 13:24:30 -06:00
Eduardo Habkost
c58a6694f1 add Westmere as a qemu cpu model (v2)
Version 1 of this patch was:

Message-Id: <1307041990-26194-11-git-send-email-ehabkost@redhat.com
http://marc.info/?l=qemu-devel&m=130704415919346

This version doesn't have the duplicate feature bits on extfeature_edx, though,
as they are being removed from the Intel models (as they are reserved bits on
Intel CPUs).

Version 1 patch description:

    This patch adds Westmere as a qemu cpu model.  The only
    additional guest visible feature of a Westmere relative
    to Nehalem is the inclusion of AES instructions.  However
    as other non-ABI visible modifications exist along with
    fabrication changes, the CPUID data of the corresponding
    deployed silicon was altered slightly to reflect this.

    We've seen isolated cases where apparently unrelated yet
    slightly incoherent CPUID data has caused problems, most
    notably during guest boot.  Providing Westmere as a
    model separate fro Nehalem allows us to more easily address
    such quirks.

    [ehabkost: edited commit message to have a better Subject line]

    Signed-off-by: john cooper <john.cooper@redhat.com>
    Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>

Changes version 1 -> version 2:
 - Remove the duplicate feature bits on extfeature_edx, that are
   reserved on Intel CPUs
 - Reorder feature flags
 - Remove x2apic from the definition because x2apic requires some fixes
   that have to be resubmitted

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-02-22 13:24:30 -06:00
Eduardo Habkost
df07ec5626 cpu defs: remove replicated flags from Intel (v2)
This patch removes the replicated feature flags from cpuid 8000_0001:edx
(extfeature_edx) from Intel models, as the duplicated feature flags are present
only on AMD CPUs. On Intel models, only the i64, syscall, and xd flags are kept
on extfeature_edx.

This is based on a previous patch from John Cooper where this was introduced
with many other changes at the same time. Original John's patch submission is
at Message-ID: <4DDAD5E7.2020002@redhat.com>, <http://marc.info/?l=qemu-devel&m=130618871926030>.

Original John's patch description was:

    cpu model bug fixes and definition corrections

    This patch was intended to address the replicated feature
    flags in cpuid 8000_0001:edx from cpuid 0000_0001:edx.
    This is due to AMD's definition where these flags are
    mostly cloned in the 8000_0001:edx cpuid function.
    qemu64 attempted to glue together the respective Intel
    and AMD nearly disjoint features and this propagated to
    the new Intel models as doing so was believed conservative
    at the time.  However after further soak and test lugging
    around this cruft doesn't provide any value, could
    conceivably confuse a guest, and has confused users trying
    to maintain/add cpu definitions.  This also caused issues
    for libvirt attempting to track this mis-encoding.

    So we've here tossed out the AMD replicated definitions
    from the Intel models, added a few replications into AMD
    definitions which were missing according to AMD's latest
    CPUID document, and reordered the config file flags to
    follow intuitive sequential bit ordering.  Also two flag
    name aliases were added for clarity to Intel models.  The
    end result being the models definitions now conform to
    their respective cpuid specifications sans x2apic which is
    emulated by kvm.

    This was tested with the following combinations:

        [Conroe, Penryn, Nehalem] x [F12-64, win64, win32] -- Intel host
        [Opteron_G1, Opteron_G2, Opteron_G3] x [F12-64, win64, win32] -- AMD host

    Yielding successful boots in all cases.

    Signed-off-by: john cooper <john.cooper@redhat.com>

Changes v1 -> v2:
 - Rebase against latest Qemu git tree

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-02-22 13:24:30 -06:00
Eduardo Habkost
0ce01375a2 cpu defs: add pse36, mca, mtrr to AMD CPU definitions (v2)
This patch adds some missing flags to extfeature_edx, that were missing
according to AMD's latest CPUID document.

This is based on a previous patch from John Cooper where this was introduced
with many other changes at the same time. Original John's patch submission is
at Message-ID: <4DDAD5E7.2020002@redhat.com>, <http://marc.info/?l=qemu-devel&m=130618871926030>.

Original John's patch description was:

    cpu model bug fixes and definition corrections

    This patch was intended to address the replicated feature
    flags in cpuid 8000_0001:edx from cpuid 0000_0001:edx.
    This is due to AMD's definition where these flags are
    mostly cloned in the 8000_0001:edx cpuid function.
    qemu64 attempted to glue together the respective Intel
    and AMD nearly disjoint features and this propagated to
    the new Intel models as doing so was believed conservative
    at the time.  However after further soak and test lugging
    around this cruft doesn't provide any value, could
    conceivably confuse a guest, and has confused users trying
    to maintain/add cpu definitions.  This also caused issues
    for libvirt attempting to track this mis-encoding.

    So we've here tossed out the AMD replicated definitions
    from the Intel models, added a few replications into AMD
    definitions which were missing according to AMD's latest
    CPUID document, and reordered the config file flags to
    follow intuitive sequential bit ordering.  Also two flag
    name aliases were added for clarity to Intel models.  The
    end result being the models definitions now conform to
    their respective cpuid specifications sans x2apic which is
    emulated by kvm.

    This was tested with the following combinations:

        [Conroe, Penryn, Nehalem] x [F12-64, win64, win32] -- Intel host
        [Opteron_G1, Opteron_G2, Opteron_G3] x [F12-64, win64, win32] -- AMD host

    Yielding successful boots in all cases.

    Signed-off-by: john cooper <john.cooper@redhat.com>

Changes v1 -> v2:
 - Rebase against latest Qemu git tree

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-02-22 13:24:29 -06:00
Eduardo Habkost
3ac8ebfe1c cpu defs: use Intel flag names for Intel models (v2)
Use 'i64' instead of 'lm' and 'xd' instead of 'nx' on Intel models.

The flags have different names on Intel docs, so use those names for clarity.

This is based on a previous patch from John Cooper where this was introduced
with many other changes at the same time. Original John's patch submission is
at Message-ID: <4DDAD5E7.2020002@redhat.com>, <http://marc.info/?l=qemu-devel&m=130618871926030>.

Changes v1 -> v2:
 - Rebase patch against latest Qemu git tree

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-02-22 13:24:28 -06:00
Eduardo Habkost
f5244e937a cpu models: reorder flag list to match bit order
This will make it easier to review and change the flag list in the future.

No behaviour change should be introduced by this, as it is just changing
the flag order on the config file.

To make sure the flag sets are really not changed by this patch, I have
used the following stupid script to compare the flag values in the
config files:
https://gist.github.com/1004885

Signed-off-by: Eduardo Habkost <ehabkost@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2012-02-22 13:24:27 -06:00
john cooper
b5ec5ce0e3 Add cpu model configuration support..
This is a reimplementation of prior versions which adds
the ability to define cpu models for contemporary processors.
The added models are likewise selected via -cpu <name>,
and are intended to displace the existing convention
of "-cpu qemu64" augmented with a series of feature flags.

A primary motivation was determination of a least common
denominator within a given processor class to simplify guest
migration.  It is still possible to modify an arbitrary model
via additional feature flags however the goal here was to
make doing so unnecessary in typical usage.  The other
consideration was providing models names reflective of
current processors.  Both AMD and Intel have reviewed the
models in terms of balancing generality of migration vs.
excessive feature downgrade relative to released silicon.

This version of the patch replaces the prior hard wired
definitions with a configuration file approach for new
models.  Existing models are thus far left as-is but may
easily be transitioned to (or may be overridden by) the
configuration file representation.

Proposed new model definitions are provided here for current
AMD and Intel processors.  Each model consists of a name
used to select it on the command line (-cpu <name>), and a
model_id which corresponds to a least common denominator
commercial instance of the processor class.

A table of names/model_ids may be queried via "-cpu ?model":

        :
    x86       Opteron_G3  AMD Opteron 23xx (Gen 3 Class Opteron)
    x86       Opteron_G2  AMD Opteron 22xx (Gen 2 Class Opteron)
    x86       Opteron_G1  AMD Opteron 240 (Gen 1 Class Opteron)
    x86          Nehalem  Intel Core i7 9xx (Nehalem Class Core i7)
    x86           Penryn  Intel Core 2 Duo P9xxx (Penryn Class Core 2)
    x86           Conroe  Intel Celeron_4x0 (Conroe/Merom Class Core 2)
        :

Also added is "-cpu ?dump" which exhaustively outputs all config
data for all defined models, and "-cpu ?cpuid" which enumerates
all qemu recognized CPUID feature flags.

The pseudo cpuid flag 'check' when added to the feature flag list
will warn when feature flags (either implicit in a cpu model or
explicit on the command line) would have otherwise been quietly
unavailable to a guest:

    # qemu-system-x86_64 ... -cpu Nehalem,check
    warning: host cpuid 0000_0001 lacks requested flag 'sse4.2|sse4_2' [0x00100000]
    warning: host cpuid 0000_0001 lacks requested flag 'popcnt' [0x00800000]

A similar 'enforce' pseudo flag exists which in addition
to the above causes qemu to error exit if requested flags are
unavailable.

Configuration data for a cpu model resides in the target config
file which by default will be installed as:

    /usr/local/etc/qemu/target-<arch>.conf

The format of this file should be self explanatory given the
definitions for the above six models and essentially mimics
the structure of the static x86_def_t x86_defs.

Encoding of cpuid flags names now allows aliases for both the
configuration file and the command line which reconciles some
Intel/AMD/Linux/Qemu naming differences.

This patch was tested relative to qemu.git.

Signed-off-by: john cooper <john.cooper@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2010-02-22 16:16:17 -06:00