Re: [PATCH v7 10/17] arm/xen: Get event-channel irq through HVM_PARAM when booting with ACPI

Julien Grall
2016-03-29T16:36:04Z

Hi Shannon,

On 24/03/16 14:44, Shannon Zhao wrote:
> When booting with ACPI, it could get the event-channel irq through

The kernel will always get the event-channel IRQ through
HVM_PARAM_CALLBACK_IRQ.

So I would say: ", the kernel will get the event-channel..."

> HVM_PARAM_CALLBACK_IRQ.
>
> Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
> Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
> ---
> arch/arm/xen/enlighten.c | 36 +++++++++++++++++++++++++++++++++++-
> 1 file changed, 35 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
> index d94f726..680aae0 100644
> --- a/arch/arm/xen/enlighten.c
> +++ b/arch/arm/xen/enlighten.c
> @@ -30,6 +30,7 @@
> #include <linux/time64.h>
> #include <linux/timekeeping.h>
> #include <linux/timekeeper_internal.h>
> +#include <linux/acpi.h>
>
> #include <linux/mm.h>
>
> @@ -278,6 +279,35 @@ void __init xen_early_init(void)
> add_preferred_console("hvc", 0, NULL);
> }
>
> +static void __init xen_acpi_guest_init(void)
> +{
> +#ifdef CONFIG_ACPI
> + struct xen_hvm_param a;
> + int interrupt, trigger, polarity;
> +
> + a.domid = DOMID_SELF;
> + a.index = HVM_PARAM_CALLBACK_IRQ;
> + xen_events_irq = 0;
> +
> + if (!HYPERVISOR_hvm_op(HVMOP_get_param, &a)) {
> + if ((a.value >> 56) == HVM_PARAM_CALLBACK_TYPE_PPI) {
> + interrupt = a.value & 0xff;
> + trigger = ((a.value >> 8) & 0x1) ? ACPI_EDGE_SENSITIVE
> + : ACPI_LEVEL_SENSITIVE;
> + polarity = ((a.value >> 8) & 0x2) ? ACPI_ACTIVE_LOW
> + : ACPI_ACTIVE_HIGH;
> + xen_events_irq = acpi_register_gsi(NULL, interrupt,
> + trigger, polarity);
> + }
> + }

Can you invert the condition to remove one layer of indentation?

Regards,

--
Julien Grall