Re: [PATCH] clocksource/drivers/arm_arch_timer: Mark EL2 virtual timer broken for Tegra194/234

[Marc Zyngier <maz@kernel.org>]

On Wed, 22 Jul 2026 13:56:51 +0100,
Jon Hunter <jonathanh@nvidia.com> wrote:
> 
> The following warning is being observed on Tegra194 and Tegra234
> platforms ...
> 
>  arch_timer: [Firmware Bug]: VHE-capable CPU without EL2 virtual timer
>   interrupt
> 
> Adding the missing EL2 virtual timer in device-tree for Tegra194 and
> Tegra234 is causing boot issues for both devices.
> 
> The Tegra194 device includes a GIC-400 which defines PPIs for sec-phys,
> phys, virt and hyp-phys timer interrupts (per the dt-binding
> arm,arch_timer.yaml) but there is no PPI hyp-virt (EL2 virtual) timer
> and hence this is not supported for this device.
> 
> The Tegra234 device does have a PPI for the EL2 virtual timer, but
> during CPU idle transitions into low-power states this timer is not
> preserved currently by firmware and hence causes boot issues when CPU
> idle is enabled.
> 
> Avoid the warning for Tegra194 and Tegra234 devices by marking the EL2
> virtual timer as broken.
> 
> Suggested-by: Marc Zyngier <maz@kernel.org>

This isn't what I suggested at [1]. The warnings are *required*,
because these systems are not compliant to the specification. Full
timer support was not optional last time I checked.

Thanks,

	M.

[1] https://lore.kernel.org/all/878q898ulx.wl-maz@kernel.org/

-- 
Without deviation from the norm, progress is not possible.