Re: [PATCH v5 6/9] irqchip/gic-v3: Parse and export virtual GIC information

Shanker Donthineni
2016-04-11T15:24:05Z

Hi Julien,

On 04/11/2016 09:27 AM, Julien Grall wrote:
> Hello Hanjun,
>
> On 11/04/16 06:27, Hanjun Guo wrote:
>> On 2016/4/4 19:37, Julien Grall wrote:
>>> +static void __init gic_acpi_setup_kvm_info(void)
>>> +{
>>> + int irq;
>>> +
>>> + if (!gic_acpi_collect_virt_info()) {
>>> + pr_warn("Unable to get hardware information used for
>>> virtualization\n");
>>> + return;
>>> + }
>>> +
>>> + gic_v3_kvm_info.type = GIC_V3;
>>> +
>>> + irq = acpi_register_gsi(NULL, acpi_data.maint_irq,
>>> + acpi_data.maint_irq_mode,
>>> + ACPI_ACTIVE_HIGH);
>>> + if (irq <= 0)
>>> + return;
>>> +
>>> + gic_v3_kvm_info.maint_irq = irq;
>>> +
>>> + if (acpi_data.vcpu_base) {
>>
>> Sorry, I'm not familiar with KVM, but I got a question here, will
>> KVM works without valid vcpu_base in GICv3 mode?
>
Yes, KVM works without vcpu_base in GICv3 mode. The vcpu_base will be used
for emulatingvGICv2 feature. The vGICv3 emulation isdone through the
system registers.

> vcpu_base is only required for supporting GICv2 on GICv3.
>
Yes, you are right,

> Regards,
>

--
Shanker Donthineni
Qualcomm Technologies, Inc. on behalf of Qualcomm Innovation Center, Inc.
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, a Linux Foundation Collaborative Project