Re: [Xen-devel] [PATCH v2 09/16] arm/xen: Get event-channel irq through HVM_PARAM when booting with ACPI

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

On 2016/1/18 22:38, Stefano Stabellini wrote:
> On Fri, 15 Jan 2016, Shannon Zhao wrote:
>> From: Shannon Zhao <shannon.zhao-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
>>
>> When booting with ACPI, it could get the event-channel irq through
>> HVM_PARAM_CALLBACK_IRQ.
>>
>> Signed-off-by: Shannon Zhao <shannon.zhao-QSEj5FYQhm4dnm+yROfE0A@public.gmane.org>
>> ---
>>  arch/arm/xen/enlighten.c | 30 +++++++++++++++++++++++++++++-
>>  1 file changed, 29 insertions(+), 1 deletion(-)
>>
>> diff --git a/arch/arm/xen/enlighten.c b/arch/arm/xen/enlighten.c
>> index 6d90a62..4e78c49 100644
>> --- a/arch/arm/xen/enlighten.c
>> +++ b/arch/arm/xen/enlighten.c
>> @@ -29,6 +29,7 @@
>>  #include <linux/time64.h>
>>  #include <linux/timekeeping.h>
>>  #include <linux/timekeeper_internal.h>
>> +#include <linux/acpi.h>
>>  
>>  #include <linux/mm.h>
>>  
>> @@ -270,7 +271,34 @@ static int __init xen_guest_init(void)
>>  	if (!xen_domain())
>>  		return 0;
>>  
>> -	xen_events_irq = irq_of_parse_and_map(xen_node, 0);
>> +	if (!acpi_disabled) {
>> +#ifdef CONFIG_ACPI
> 
> I think it would be best to move the acpi specific and DT specific
> initializations out of xen_guest_init. Then at the beginning of
> xen_guest_init, call only the one that applies.  The acpi init function
> could be ifdef'ed CONFIG_ACPI. Making sure that acpi_disabled is 1 when
> !CONFIG_ACPI, we could even avoid all ifdef's from xen_guest_init.
> 
Sure, will fix. Thanks.

> The rest is good, thanks.
> 
> 
>> +		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) == 3) {
>> +				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);
>> +			}
>> +		}
>> +
>> +#endif
>> +	} else {
>> +		xen_events_irq = irq_of_parse_and_map(xen_node, 0);
>> +	}
>> +
>>  	if (!xen_events_irq) {
>>  		pr_err("Xen event channel interrupt not found\n");
>>  		return -ENODEV;
> 
> .
> 

-- 
Shannon