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

[Shannon Zhao <zhaoshenglong-hv44wF8Li93QT0dZR+AlfA@public.gmane.org>]

On 2016/3/30 0:35, Julien Grall wrote:
> 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-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
>> Reviewed-by: Stefano Stabellini <stefano.stabellini-mvvWK6WmYclDPfheJLI6IQ@public.gmane.org>
>> ---
>>   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?
Sure, will update.

Thanks,
-- 
Shannon