Describe the GICv3 distributor and redistributor registers in our
structure. This adds a special macro to deal with the split of
SGI/PPI in the redistributor and SPIs in the distributor, which
allows us to reuse the existing GICv2 handlers for those registers
which are compatible.
Also we register the separate MMIO page for the redistributor
registers dealing with private interrupts.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>

Changelog RFC..v1:
- adapt to new MMIO registration approach:
  register one device for the distributor and two for each VCPU
- implement special handling for private interrupts
- remove empty stub functions
- make IGROUPR return RAO
---
 virt/kvm/arm/vgic/vgic.h      |  16 +++
 virt/kvm/arm/vgic/vgic_mmio.c | 269 ++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 285 insertions(+)

diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 59fddbf..ccae13e 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h

@@ -40,6 +40,10 @@ void vgic_v3_fold_lr_state(struct kvm_vcpu *vcpu);
 void vgic_v3_populate_lr(struct kvm_vcpu *vcpu, struct vgic_irq *irq, int lr);
 void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr);
 void vgic_v3_set_underflow(struct kvm_vcpu *vcpu);
+int vgic_v3_dist_access(struct kvm_vcpu *vcpu, bool is_write,
+			int offset, int len, void *val);
+int vgic_v3_redist_access(struct kvm_vcpu *vcpu, bool is_write,
+			  int offset, int len, void *val);
 #else
 static inline void vgic_v3_process_maintenance(struct kvm_vcpu *vcpu)
 {

@@ -61,6 +65,18 @@ static inline void vgic_v3_clear_lr(struct kvm_vcpu *vcpu, int lr)
 static inline void vgic_v3_set_underflow(struct kvm_vcpu *vcpu)
 {
 }
+
+static inline int vgic_v3_dist_access(struct kvm_vcpu *vcpu, bool is_write,
+				      int offset, int len, void *val)
+{
+	return -ENXIO;
+}
+
+static inline int vgic_v3_redist_access(struct kvm_vcpu *vcpu, bool is_write,
+					int offset, int len, void *val)
+{
+	return -ENXIO;
+}
 #endif
 
 #endif

diff --git a/virt/kvm/arm/vgic/vgic_mmio.c b/virt/kvm/arm/vgic/vgic_mmio.c
index daa2e00..4a31d60 100644
--- a/virt/kvm/arm/vgic/vgic_mmio.c
+++ b/virt/kvm/arm/vgic/vgic_mmio.c

@@ -17,6 +17,8 @@
 #include <kvm/vgic/vgic.h>
 #include <linux/bitops.h>
 #include <linux/irqchip/arm-gic.h>
+#include <linux/irqchip/arm-gic-v3.h>