Merge branch kvm-arm64/nv-timers into kvmarm-master/next

* kvm-arm64/nv-timers:
  : .
  : Nested Virt support for the EL2 timers. From the initial cover letter:
  :
  : "Here's another batch of NV-related patches, this time bringing in most
  : of the timer support for EL2 as well as nested guests.
  :
  : The code is pretty convoluted for a bunch of reasons:
  :
  : - FEAT_NV2 breaks the timer semantics by redirecting HW controls to
  :   memory, meaning that a guest could setup a timer and never see it
  :   firing until the next exit
  :
  : - We go try hard to reflect the timer state in memory, but that's not
  :   great.
  :
  : - With FEAT_ECV, we can finally correctly emulate the virtual timer,
  :   but this emulation is pretty costly
  :
  : - As a way to make things suck less, we handle timer reads as early as
  :   possible, and only defer writes to the normal trap handling
  :
  : - Finally, some implementations are badly broken, and require some
  :   hand-holding, irrespective of NV support. So we try and reuse the NV
  :   infrastructure to make them usable. This could be further optimised,
  :   but I'm running out of patience for this sort of HW.
  :
  : [...]"
  : .
  KVM: arm64: nv: Fix doc header layout for timers
  KVM: arm64: nv: Document EL2 timer API
  KVM: arm64: Work around x1e's CNTVOFF_EL2 bogosity
  KVM: arm64: nv: Sanitise CNTHCTL_EL2
  KVM: arm64: nv: Propagate CNTHCTL_EL2.EL1NV{P,V}CT bits
  KVM: arm64: nv: Add trap routing for CNTHCTL_EL2.EL1{NVPCT,NVVCT,TVT,TVCT}
  KVM: arm64: Handle counter access early in non-HYP context
  KVM: arm64: nv: Accelerate EL0 counter accesses from hypervisor context
  KVM: arm64: nv: Accelerate EL0 timer read accesses when FEAT_ECV in use
  KVM: arm64: nv: Use FEAT_ECV to trap access to EL0 timers
  KVM: arm64: nv: Publish emulated timer interrupt state in the in-memory state
  KVM: arm64: nv: Sync nested timer state with FEAT_NV2
  KVM: arm64: nv: Add handling of EL2-specific timer registers

Signed-off-by: Marc Zyngier <maz@kernel.org>

1 files changed, 15 insertions, 0 deletions

diff --git a/arch/arm64/kvm/nested.c b/arch/arm64/kvm/nested.c
index 4cada42788f78..9895372fb3b6a 100644
--- a/arch/arm64/kvm/nested.c
+++ b/arch/arm64/kvm/nested.c
@@ -1271,6 +1271,21 @@ int kvm_init_nv_sysregs(struct kvm *kvm)
 		res0 |= MDCR_EL2_EnSTEPOP;
 	set_sysreg_masks(kvm, MDCR_EL2, res0, res1);
 
+	/* CNTHCTL_EL2 */
+	res0 = GENMASK(63, 20);
+	res1 = 0;
+	if (!kvm_has_feat(kvm, ID_AA64PFR0_EL1, RME, IMP))
+		res0 |= CNTHCTL_CNTPMASK | CNTHCTL_CNTVMASK;
+	if (!kvm_has_feat(kvm, ID_AA64MMFR0_EL1, ECV, CNTPOFF)) {
+		res0 |= CNTHCTL_ECV;
+		if (!kvm_has_feat(kvm, ID_AA64MMFR0_EL1, ECV, IMP))
+			res0 |= (CNTHCTL_EL1TVT | CNTHCTL_EL1TVCT |
+				 CNTHCTL_EL1NVPCT | CNTHCTL_EL1NVVCT);
+	}
+	if (!kvm_has_feat(kvm, ID_AA64MMFR1_EL1, VH, IMP))
+		res0 |= GENMASK(11, 8);
+	set_sysreg_masks(kvm, CNTHCTL_EL2, res0, res1);
+
 	return 0;
 }