Add a small blurb describing how the event filtering API gets used.
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
Documentation/virt/kvm/devices/vcpu.txt | 28 +++++++++++++++++++++++++
1 file changed, 28 insertions(+)
diff --git a/Documentation/virt/kvm/devices/vcpu.txt b/Documentation/virt/kvm/devices/vcpu.txt
index 6f3bd64a05b0..76902e6bbc05 100644
--- a/Documentation/virt/kvm/devices/vcpu.txt
+++ b/Documentation/virt/kvm/devices/vcpu.txt
@@ -36,6 +36,34 @@ Request the initialization of the PMUv3. If using the PMUv3 with an in-kernel
virtual GIC implementation, this must be done after initializing the in-kernel
irqchip.
+1.3 ATTRIBUTE: KVM_ARM_VCPU_PMU_V3_FILTER
+Parameters: in kvm_device_attr.addr the address for a PMU event filter is a
+ pointer to a struct kvm_pmu_event_filter
+Returns: -ENODEV: PMUv3 not supported or GIC not initialized
+ -ENXIO: PMUv3 not properly configured or in-kernel irqchip not
+ configured as required prior to calling this attribute
+ -EBUSY: PMUv3 already initialized
+
+Request the installation of a PMU event filter describe as follows:
+
+struct kvm_pmu_event_filter {
+ __u16 base_event;
+ __u16 nevents;
+
+#define KVM_PMU_EVENT_ALLOW 0
+#define KVM_PMU_EVENT_DENY 1
+
+ __u8 action;
+ __u8 pad[3];
+};
+
+A filter range is defined as the range [base_event, base_event + nevents[,
+together with an action (KVM_PMU_EVENT_ALLOW or KVM_PMU_EVENT_DENY). The
+first registered range defines the global policy (global ALLOW if the first
+action is DENY, global DENY if the first action is ALLOW). Multiple ranges
+can be programmed, and but fit within the 16bit space defined by the ARMv8.1
+PMU architecture.
+
2. GROUP: KVM_ARM_VCPU_TIMER_CTRL
Architectures: ARM,ARM64
--
2.20.1
