Re: [PATCH 05/10] hw/arm/virt: Fix devicetree warning about the timer node

[Peter Maydell]

On Wed, 24 Aug 2022 at 16:51, Jean-Philippe Brucker
<jean-philippe@linaro.org> wrote:
>
> The compatible property of the Arm timer should contain either
> "arm,armv7-timer" or "arm,armv8-timer", not both.
>
>   timer: compatible: 'oneOf' conditional failed, one must be fixed:
>         ['arm,armv8-timer', 'arm,armv7-timer'] is too long
>   From schema: 
> linux/Documentation/devicetree/bindings/timer/arm,arch_timer.yaml
>
> Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
> ---
>  hw/arm/virt.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/hw/arm/virt.c b/hw/arm/virt.c
> index ca5d213895..5935f32a44 100644
> --- a/hw/arm/virt.c
> +++ b/hw/arm/virt.c
> @@ -344,7 +344,7 @@ static void fdt_add_timer_nodes(const VirtMachineState 
> *vms)
>
>      armcpu = ARM_CPU(qemu_get_cpu(0));
>      if (arm_feature(&armcpu->env, ARM_FEATURE_V8)) {
> -        const char compat[] = "arm,armv8-timer\0arm,armv7-timer";
> +        const char compat[] = "arm,armv8-timer";
>          qemu_fdt_setprop(ms->fdt, "/timer", "compatible",
>                           compat, sizeof(compat));
>      } else {

Are we really sure there are no existing guests out there that are
looking for this device under "armv7-timer" ?

This used to be valid DT before Linux kernel commit 4d2bb3e65035954,
which changed from "should at least contain one of" to requiring
exactly one-of, and that was only in 2018.

thanks
-- PMM