[PATCH 26/45] KVM: arm/arm64: vgic-new: Add GICv3 IDREGS register handler

[Andre Przywara]

Signed-off-by: Andre Przywara <andre.przywara at arm.com>
---
 virt/kvm/arm/vgic/vgic_mmio.c | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/virt/kvm/arm/vgic/vgic_mmio.c b/virt/kvm/arm/vgic/vgic_mmio.c
index 7d275a7..dafa235 100644
--- a/virt/kvm/arm/vgic/vgic_mmio.c
+++ b/virt/kvm/arm/vgic/vgic_mmio.c
@@ -784,6 +784,23 @@ static int vgic_mmio_read_v3r_iidr(struct kvm_vcpu *vcpu,
 	return 0;
 }
 
+static int vgic_mmio_read_v3_idregs(struct kvm_vcpu *vcpu,
+				    struct kvm_io_device *dev,
+				    gpa_t addr, int len, void *val)
+{
+	u32 regnr = (addr & 0x3f) - (GICD_IDREGS & 0x3f);
+	u32 reg = 0;
+
+	switch (regnr + GICD_IDREGS) {
+	case GICD_PIDR2:
+		/* report a GICv3 compliant implementation */
+		reg = 0x3b;
+		break;
+	}
+
+	write_mask32(reg , addr & 3, len, val);
+	return 0;
+}
 #endif
 
 /*
@@ -860,7 +877,7 @@ struct vgic_register_region vgic_v3_dist_registers[] = {
 	REGISTER_DESC_WITH_BITS_PER_IRQ_SHARED(GICD_IROUTER,
 		vgic_mmio_read_nyi, vgic_mmio_write_nyi, 64),
 	REGISTER_DESC_WITH_LENGTH(GICD_IDREGS,
-		vgic_mmio_read_nyi, vgic_mmio_write_wi, 48),
+		vgic_mmio_read_v3_idregs, vgic_mmio_write_wi, 48),
 };
 
 struct vgic_register_region vgic_v3_redist_registers[] = {
@@ -875,7 +892,7 @@ struct vgic_register_region vgic_v3_redist_registers[] = {
 	REGISTER_DESC_WITH_LENGTH(GICR_PENDBASER,
 		vgic_mmio_read_raz, vgic_mmio_write_wi, 8),
 	REGISTER_DESC_WITH_LENGTH(GICR_IDREGS,
-		vgic_mmio_read_nyi, vgic_mmio_write_wi, 48),
+		vgic_mmio_read_v3_idregs, vgic_mmio_write_wi, 48),
 };
 
 struct vgic_register_region vgic_v3_private_registers[] = {
-- 
2.7.3