Although FP8 support was merged in 6.9, the KVM side was dropped, with no sign of it being picked up again. Given that its absence is getting in the way of NV upstreaming (HCRX_EL2 needs fleshing out), here's a small series addressing it. The support is following the save/restore model established for the rest of the FP code, with FPMR being tied to it. The sole additions are the handling of traps in a nested context, and the corresponding ID registers being made writable. As an extra cleanup, SVCR and FPMR are moved into the sysreg array. Patches are on top of kvmarm/next, as this would otherwise majorly conflict. Note that this is compile-tested only, as I have no access to FP8 HW or model (and running NV in a model is not something I wish to entertain ever again). Also, this is *not* 6.11 material. 6.12 if we're lucky. Marc Zyngier (7): KVM: arm64: Move SVCR into the sysreg array KVM: arm64: Move FPMR into the sysreg array KVM: arm64: Add save/restore support for FPMR KVM: arm64: Honor trap routing for FPMR KVM: arm64: Expose ID_AA64FPFR0_EL1 as a writable ID reg KVM: arm64: Enable FP8 support when available and configured KVM: arm64: Expose ID_AA64PFR2_EL1 to userspace and guests arch/arm64/include/asm/kvm_host.h | 16 ++++++++++-- arch/arm64/kvm/emulate-nested.c | 8 ++++++ arch/arm64/kvm/fpsimd.c | 5 ++-- arch/arm64/kvm/hyp/nvhe/hyp-main.c | 4 +++ arch/arm64/kvm/hyp/nvhe/switch.c | 10 +++++++ arch/arm64/kvm/hyp/vhe/switch.c | 4 +++ arch/arm64/kvm/sys_regs.c | 42 +++++++++++++++++++++++++++--- 7 files changed, 82 insertions(+), 7 deletions(-) -- 2.39.2
