MIPS KVM Guest FPU & SIMD (MSA) Support

Add guest FPU and MIPS SIMD Architecture (MSA) support to MIPS KVM, by
enabling the host FPU/MSA while in guest mode. This adds two new KVM
capabilities, KVM_CAP_MIPS_FPU & KVM_CAP_MIPS_MSA, and supports the 3 FP
register modes (FR=0, FR=1, FRE=1), and 128-bit MSA vector registers,
with lazy FPU/MSA context save and restore.

Some required MIPS FP/MSA fixes are merged in from a branch in the MIPS
tree first.
MIPS: KVM: Wire up MSA capability

Now that the code is in place for KVM to support MIPS SIMD Architecutre
(MSA) in MIPS guests, wire up the new KVM_CAP_MIPS_MSA capability.

For backwards compatibility, the capability must be explicitly enabled
in order to detect or make use of MSA from the guest.

The capability is not supported if the hardware supports MSA vector
partitioning, since the extra support cannot be tested yet and it
extends the state that the userland program would have to save.

Signed-off-by: James Hogan <james.hogan@imgtec.com>
Acked-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Gleb Natapov <gleb@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-mips@linux-mips.org
Cc: kvm@vger.kernel.org
Cc: linux-api@vger.kernel.org
Cc: linux-doc@vger.kernel.org
3 files changed