KVM: arm64: vgic-its: Introduce ITS emulation file with MMIO framework

The ARM GICv3 ITS emulation code goes into a separate file, but needs
to be connected to the GICv3 emulation, of which it is an option.
The ITS MMIO handlers require the respective ITS pointer to be passed in,
so we amend the existing VGIC MMIO framework to let it cope with that.
Also we introduce the basic ITS data structure and initialize it, but
don't return any success yet, as we are not yet ready for the show.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 21 insertions, 1 deletions

diff --git a/include/kvm/arm_vgic.h b/include/kvm/arm_vgic.h
index df2dec5ef620..685f33975ce4 100644
--- a/include/kvm/arm_vgic.h
+++ b/include/kvm/arm_vgic.h
@@ -108,15 +108,35 @@ struct vgic_irq {
 };
 
 struct vgic_register_region;
+struct vgic_its;
+
+enum iodev_type {
+	IODEV_CPUIF,
+	IODEV_DIST,
+	IODEV_REDIST,
+	IODEV_ITS
+};
 
 struct vgic_io_device {
 	gpa_t base_addr;
-	struct kvm_vcpu *redist_vcpu;
+	union {
+		struct kvm_vcpu *redist_vcpu;
+		struct vgic_its *its;
+	};
 	const struct vgic_register_region *regions;
+	enum iodev_type iodev_type;
 	int nr_regions;
 	struct kvm_io_device dev;
 };
 
+struct vgic_its {
+	/* The base address of the ITS control register frame */
+	gpa_t			vgic_its_base;
+
+	bool			enabled;
+	struct vgic_io_device	iodev;
+};
+
 struct vgic_dist {
 	bool			in_kernel;
 	bool			ready;