Re: [PATCH v11 12/17] ARM64: ACPI: Check if it runs on Xen to enable or disable ACPI

[Stefano Stabellini]

Hello Mark,

do you think that this patch addresses your previous comments
(http://marc.info/?l=devicetree&m=145926913008544&w=2) appropriately?

Thanks,

Stefano

On Thu, 7 Apr 2016, Shannon Zhao wrote:
> From: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
> 
> When it's a Xen domain0 booting with ACPI, it will supply a /chosen and
> a /hypervisor node in DT. So check if it needs to enable ACPI.
> 
> Signed-off-by: Shannon Zhao <shannon.zhao@xxxxxxxxxx>
> Reviewed-by: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
> Acked-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
> ---
>  arch/arm64/kernel/acpi.c | 14 ++++++++++----
>  1 file changed, 10 insertions(+), 4 deletions(-)
> 
> diff --git a/arch/arm64/kernel/acpi.c b/arch/arm64/kernel/acpi.c
> index d1ce8e2..57ee317 100644
> --- a/arch/arm64/kernel/acpi.c
> +++ b/arch/arm64/kernel/acpi.c
> @@ -67,10 +67,15 @@ static int __init dt_scan_depth1_nodes(unsigned long node,
>  {
>  	/*
>  	 * Return 1 as soon as we encounter a node at depth 1 that is
> -	 * not the /chosen node.
> +	 * not the /chosen node, or /hypervisor node with compatible
> +	 * string "xen,xen".
>  	 */
> -	if (depth == 1 && (strcmp(uname, "chosen") != 0))
> -		return 1;
> +	if (depth == 1 && (strcmp(uname, "chosen") != 0)) {
> +		if (strcmp(uname, "hypervisor") != 0 ||
> +		    !of_flat_dt_is_compatible(node, "xen,xen"))
> +			return 1;
> +	}
> +
>  	return 0;
>  }
>  
> @@ -184,7 +189,8 @@ void __init acpi_boot_table_init(void)
>  	/*
>  	 * Enable ACPI instead of device tree unless
>  	 * - ACPI has been disabled explicitly (acpi=off), or
> -	 * - the device tree is not empty (it has more than just a /chosen node)
> +	 * - the device tree is not empty (it has more than just a /chosen node,
> +	 *   and a /hypervisor node when running on Xen)
>  	 *   and ACPI has not been force enabled (acpi=force)
>  	 */
>  	if (param_acpi_off ||
> -- 
> 2.0.4
> 
>