Hey Marc, On Fri, May 26, 2023 at 03:33:37PM +0100, Marc Zyngier wrote: > To initialise the timer access from EL2 when HCR_EL2.E2H is set, > we must make use the CNTHCTL_EL2 formap used is appropriate. > > This amounts to shifting the timer/counter enable bits by 10 > to the left. > > Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx> > --- > arch/arm64/include/asm/el2_setup.h | 5 +++++ > arch/arm64/kvm/hyp/nvhe/hyp-init.S | 9 +++++++++ > 2 files changed, 14 insertions(+) > > diff --git a/arch/arm64/include/asm/el2_setup.h b/arch/arm64/include/asm/el2_setup.h > index 037724b19c5c..225bf1f2514d 100644 > --- a/arch/arm64/include/asm/el2_setup.h > +++ b/arch/arm64/include/asm/el2_setup.h > @@ -34,6 +34,11 @@ > */ > .macro __init_el2_timers > mov x0, #3 // Enable EL1 physical timers > + mrs x1, hcr_el2 > + and x1, x1, #HCR_E2H > + cbz x1, .LnVHE_\@ > + lsl x0, x0, #10 > +.LnVHE_\@: > msr cnthctl_el2, x0 > msr cntvoff_el2, xzr // Clear virtual offset > .endm > diff --git a/arch/arm64/kvm/hyp/nvhe/hyp-init.S b/arch/arm64/kvm/hyp/nvhe/hyp-init.S > index a6d67c2bb5ae..f9ee10e29497 100644 > --- a/arch/arm64/kvm/hyp/nvhe/hyp-init.S > +++ b/arch/arm64/kvm/hyp/nvhe/hyp-init.S > @@ -95,6 +95,15 @@ SYM_CODE_START_LOCAL(___kvm_hyp_init) > ldr x1, [x0, #NVHE_INIT_HCR_EL2] > msr hcr_el2, x1 > > + mov x2, #HCR_E2H > + and x2, x1, x2 > + cbz x2, 1f > + > + mrs x1, cnthctl_el2 > + and x1, x1, #~(BIT(0) | BIT(1)) > + orr x1, x1, #(BIT(10) | BIT(11)) > + msr cnthctl_el2, x1 > +1: Can this be done with an alternative block keyed on ARM64_KVM_HVHE? I get that __init_el2_timers needs to run before the cpu caps have been evaluated, but I don't think the same applies for ___kvm_hyp_init -- Thanks, Oliver
