[PATCH v2 05/25] KVM: arm64: vgic-v3: Add ICV_BPR1_EL1 handler

Marc Zyngier
2017-06-01T10:20:57Z

Add a handler for reading/writing the guest's view of the ICC_BPR1_EL1
register, which is located in the ICH_VMCR_EL2.BPR1 field.

Reviewed-by: Eric Auger <eric.auger@redhat.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
virt/kvm/arm/hyp/vgic-v3-sr.c | 51 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 51 insertions(+)

diff --git a/virt/kvm/arm/hyp/vgic-v3-sr.c b/virt/kvm/arm/hyp/vgic-v3-sr.c
index 943bf11252d9..6254eaf72a77 100644
--- a/virt/kvm/arm/hyp/vgic-v3-sr.c
+++ b/virt/kvm/arm/hyp/vgic-v3-sr.c
@@ -375,6 +375,51 @@ void __hyp_text __vgic_v3_write_vmcr(u32 vmcr)

#ifdef CONFIG_ARM64

+static unsigned int __hyp_text __vgic_v3_get_bpr0(u32 vmcr)
+{
+ return (vmcr & ICH_VMCR_BPR0_MASK) >> ICH_VMCR_BPR0_SHIFT;
+}
+
+static unsigned int __hyp_text __vgic_v3_get_bpr1(u32 vmcr)
+{
+ unsigned int bpr;
+
+ if (vmcr & ICH_VMCR_CBPR_MASK) {
+ bpr = __vgic_v3_get_bpr0(vmcr);
+ if (bpr < 7)
+ bpr++;
+ } else {
+ bpr = (vmcr & ICH_VMCR_BPR1_MASK) >> ICH_VMCR_BPR1_SHIFT;
+ }
+
+ return bpr;
+}
+
+static void __hyp_text __vgic_v3_read_bpr1(struct kvm_vcpu *vcpu, u32 vmcr, int rt)
+{
+ vcpu_set_reg(vcpu, rt, __vgic_v3_get_bpr1(vmcr));
+}
+
+static void __hyp_text __vgic_v3_write_bpr1(struct kvm_vcpu *vcpu, u32 vmcr, int rt)
+{
+ u64 val = vcpu_get_reg(vcpu, rt);
+ u8 bpr_min = 8 - vtr_to_nr_pre_bits(read_gicreg(ICH_VTR_EL2));
+
+ if (vmcr & ICH_VMCR_CBPR_MASK)
+ return;
+
+ /* Enforce BPR limiting */
+ if (val < bpr_min)
+ val = bpr_min;
+
+ val <<= ICH_VMCR_BPR1_SHIFT;
+ val &= ICH_VMCR_BPR1_MASK;
+ vmcr &= ~ICH_VMCR_BPR1_MASK;
+ vmcr |= val;
+
+ __vgic_v3_write_vmcr(vmcr);
+}
+
int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
{
int rt;
@@ -397,6 +442,12 @@ int __hyp_text __vgic_v3_perform_cpuif_access(struct kvm_vcpu *vcpu)
is_read = (esr & ESR_ELx_SYS64_ISS_DIR_MASK) == ESR_ELx_SYS64_ISS_DIR_READ;

switch (sysreg) {
+ case SYS_ICC_BPR1_EL1:
+ if (is_read)
+ fn = __vgic_v3_read_bpr1;
+ else
+ fn = __vgic_v3_write_bpr1;
+ break;
default:
return 0;
}
--
2.11.0