Re: [RFC PATCH v8 25/35] x86/apic: Support LAPIC timer for Secure AVIC

[Tianyu Lan]

On Wed, Jul 9, 2025 at 11:42 AM Neeraj Upadhyay <Neeraj.Upadhyay@xxxxxxx> wrote:
>
> Secure AVIC requires LAPIC timer to be emulated by the hypervisor.
> KVM already supports emulating LAPIC timer using hrtimers. In order
> to emulate LAPIC timer, APIC_LVTT, APIC_TMICT and APIC_TDCR register
> values need to be propagated to the hypervisor for arming the timer.
> APIC_TMCCT register value has to be read from the hypervisor, which
> is required for calibrating the APIC timer. So, read/write all APIC
> timer registers from/to the hypervisor.
>
> Co-developed-by: Kishon Vijay Abraham I <kvijayab@xxxxxxx>
> Signed-off-by: Kishon Vijay Abraham I <kvijayab@xxxxxxx>
> Signed-off-by: Neeraj Upadhyay <Neeraj.Upadhyay@xxxxxxx>
> ---
> Changes since v7:
>  - No change.

Reviewed-by: Tianyu Lan <tiala@xxxxxxxxxxxxx>
--
Thanks
Tianyu Lan