[v2,00/12] KVM: arm64: Add NV timer support

Message

Marc Zyngier Dec. 17, 2024, 2:23 p.m. UTC

Here's another version of the series initially posted at [1], which
implements support for timers in NV context.

From v1:

- Repainted EL0->EL1 when rambling about the timers

- Simplified access to EL1 counters from HYP context

- Update the status register when handled as an early trap

- Added some documentation about the default PPI numbers

The whole thing has been tested with 6.13-rc3 as part of the my NV
integration branch [2], and is functional enough to run an L3 guest
with kvmtool as the VMM and EDK2 as the firmware. YMMV.

[1] https://lore.kernel.org/r/[e-mail]
[2] https://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms.git/log/?h=kvm-arm64/nv-next

Marc Zyngier (12):
  KVM: arm64: nv: Add handling of EL2-specific timer registers
  KVM: arm64: nv: Sync nested timer state with FEAT_NV2
  KVM: arm64: nv: Publish emulated timer interrupt state in the
    in-memory state
  KVM: arm64: nv: Use FEAT_ECV to trap access to EL0 timers
  KVM: arm64: nv: Accelerate EL0 timer read accesses when FEAT_ECV in
    use
  KVM: arm64: nv: Accelerate EL0 counter accesses from hypervisor
    context
  KVM: arm64: Handle counter access early in non-HYP context
  KVM: arm64: nv: Add trap routing for
    CNTHCTL_EL2.EL1{NVPCT,NVVCT,TVT,TVCT}
  KVM: arm64: nv: Propagate CNTHCTL_EL2.EL1NV{P,V}CT bits
  KVM: arm64: nv: Sanitise CNTHCTL_EL2
  KVM: arm64: Work around x1e's CNTVOFF_EL2 bogosity
  KVM: arm64: nv: Document EL2 timer API

 Documentation/virt/kvm/devices/vcpu.rst |  15 +-
 arch/arm64/include/asm/cputype.h        |   2 +
 arch/arm64/include/asm/kvm_host.h       |   2 +-
 arch/arm64/include/asm/sysreg.h         |   4 +
 arch/arm64/kernel/cpu_errata.c          |   8 ++
 arch/arm64/kernel/image-vars.h          |   3 +
 arch/arm64/kvm/arch_timer.c             | 179 +++++++++++++++++++++---
 arch/arm64/kvm/arm.c                    |   3 +
 arch/arm64/kvm/emulate-nested.c         |  58 +++++++-
 arch/arm64/kvm/hyp/include/hyp/switch.h |  39 ++++--
 arch/arm64/kvm/hyp/nvhe/timer-sr.c      |  16 ++-
 arch/arm64/kvm/hyp/vhe/switch.c         | 107 ++++++++++++++
 arch/arm64/kvm/nested.c                 |  15 ++
 arch/arm64/kvm/sys_regs.c               | 146 ++++++++++++++++++-
 arch/arm64/tools/cpucaps                |   1 +
 include/clocksource/arm_arch_timer.h    |   6 +
 include/kvm/arm_arch_timer.h            |  23 +++
 17 files changed, 580 insertions(+), 47 deletions(-)