[PATCH 07/31] arm64: KVM: Implement vgic-v3 save/restore
Marc Zyngier
marc.zyngier at arm.com
Thu Dec 24 03:12:15 PST 2015
Implement the vgic-v3 save restore as a direct translation of
the assembly code version.
Signed-off-by: Marc Zyngier <marc.zyngier at arm.com>
---
arch/arm64/kvm/hyp/Makefile | 1 +
arch/arm64/kvm/hyp/hyp.h | 3 +
arch/arm64/kvm/hyp/vgic-v3-sr.c | 226 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 230 insertions(+)
create mode 100644 arch/arm64/kvm/hyp/vgic-v3-sr.c
diff --git a/arch/arm64/kvm/hyp/Makefile b/arch/arm64/kvm/hyp/Makefile
index d8d5968..d1e38ce 100644
--- a/arch/arm64/kvm/hyp/Makefile
+++ b/arch/arm64/kvm/hyp/Makefile
@@ -3,3 +3,4 @@
#
obj-$(CONFIG_KVM_ARM_HOST) += vgic-v2-sr.o
+obj-$(CONFIG_KVM_ARM_HOST) += vgic-v3-sr.o
diff --git a/arch/arm64/kvm/hyp/hyp.h b/arch/arm64/kvm/hyp/hyp.h
index ac63553..5759f9f 100644
--- a/arch/arm64/kvm/hyp/hyp.h
+++ b/arch/arm64/kvm/hyp/hyp.h
@@ -32,5 +32,8 @@
void __vgic_v2_save_state(struct kvm_vcpu *vcpu);
void __vgic_v2_restore_state(struct kvm_vcpu *vcpu);
+void __vgic_v3_save_state(struct kvm_vcpu *vcpu);
+void __vgic_v3_restore_state(struct kvm_vcpu *vcpu);
+
#endif /* __ARM64_KVM_HYP_H__ */
diff --git a/arch/arm64/kvm/hyp/vgic-v3-sr.c b/arch/arm64/kvm/hyp/vgic-v3-sr.c
new file mode 100644
index 0000000..78d05f3
--- /dev/null
+++ b/arch/arm64/kvm/hyp/vgic-v3-sr.c
@@ -0,0 +1,226 @@
+/*
+ * Copyright (C) 2012-2015 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier at arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/compiler.h>
+#include <linux/irqchip/arm-gic-v3.h>
+#include <linux/kvm_host.h>
+
+#include <asm/kvm_mmu.h>
+
+#include "hyp.h"
+
+#define vtr_to_max_lr_idx(v) ((v) & 0xf)
+#define vtr_to_nr_pri_bits(v) (((u32)(v) >> 29) + 1)
+
+#define read_gicreg(r) \
+ ({ \
+ u64 reg; \
+ asm volatile("mrs_s %0, " __stringify(r) : "=r" (reg)); \
+ reg; \
+ })
+
+#define write_gicreg(v,r) \
+ do { \
+ u64 __val = (v); \
+ asm volatile("msr_s " __stringify(r) ", %0" : : "r" (__val));\
+ } while (0)
+
+/* vcpu is already in the HYP VA space */
+void __hyp_text __vgic_v3_save_state(struct kvm_vcpu *vcpu)
+{
+ struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
+ u64 val;
+ u32 max_lr_idx, nr_pri_bits;
+
+ /*
+ * Make sure stores to the GIC via the memory mapped interface
+ * are now visible to the system register interface.
+ */
+ dsb(st);
+
+ cpu_if->vgic_vmcr = read_gicreg(ICH_VMCR_EL2);
+ cpu_if->vgic_misr = read_gicreg(ICH_MISR_EL2);
+ cpu_if->vgic_eisr = read_gicreg(ICH_EISR_EL2);
+ cpu_if->vgic_elrsr = read_gicreg(ICH_ELSR_EL2);
+
+ write_gicreg(0, ICH_HCR_EL2);
+ val = read_gicreg(ICH_VTR_EL2);
+ max_lr_idx = vtr_to_max_lr_idx(val);
+ nr_pri_bits = vtr_to_nr_pri_bits(val);
+
+ switch (max_lr_idx) {
+ case 15:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(15)] = read_gicreg(ICH_LR15_EL2);
+ case 14:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(14)] = read_gicreg(ICH_LR14_EL2);
+ case 13:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(13)] = read_gicreg(ICH_LR13_EL2);
+ case 12:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(12)] = read_gicreg(ICH_LR12_EL2);
+ case 11:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(11)] = read_gicreg(ICH_LR11_EL2);
+ case 10:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(10)] = read_gicreg(ICH_LR10_EL2);
+ case 9:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(9)] = read_gicreg(ICH_LR9_EL2);
+ case 8:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(8)] = read_gicreg(ICH_LR8_EL2);
+ case 7:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(7)] = read_gicreg(ICH_LR7_EL2);
+ case 6:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(6)] = read_gicreg(ICH_LR6_EL2);
+ case 5:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(5)] = read_gicreg(ICH_LR5_EL2);
+ case 4:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(4)] = read_gicreg(ICH_LR4_EL2);
+ case 3:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(3)] = read_gicreg(ICH_LR3_EL2);
+ case 2:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(2)] = read_gicreg(ICH_LR2_EL2);
+ case 1:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(1)] = read_gicreg(ICH_LR1_EL2);
+ case 0:
+ cpu_if->vgic_lr[VGIC_V3_LR_INDEX(0)] = read_gicreg(ICH_LR0_EL2);
+ }
+
+ switch (nr_pri_bits) {
+ case 7:
+ cpu_if->vgic_ap0r[3] = read_gicreg(ICH_AP0R3_EL2);
+ cpu_if->vgic_ap0r[2] = read_gicreg(ICH_AP0R2_EL2);
+ case 6:
+ cpu_if->vgic_ap0r[1] = read_gicreg(ICH_AP0R1_EL2);
+ default:
+ cpu_if->vgic_ap0r[0] = read_gicreg(ICH_AP0R0_EL2);
+ }
+
+ switch (nr_pri_bits) {
+ case 7:
+ cpu_if->vgic_ap1r[3] = read_gicreg(ICH_AP1R3_EL2);
+ cpu_if->vgic_ap1r[2] = read_gicreg(ICH_AP1R2_EL2);
+ case 6:
+ cpu_if->vgic_ap1r[1] = read_gicreg(ICH_AP1R1_EL2);
+ default:
+ cpu_if->vgic_ap1r[0] = read_gicreg(ICH_AP1R0_EL2);
+ }
+
+ val = read_gicreg(ICC_SRE_EL2);
+ write_gicreg(val | ICC_SRE_EL2_ENABLE, ICC_SRE_EL2);
+ isb(); /* Make sure ENABLE is set at EL2 before setting SRE at EL1 */
+ write_gicreg(1, ICC_SRE_EL1);
+}
+
+void __hyp_text __vgic_v3_restore_state(struct kvm_vcpu *vcpu)
+{
+ struct vgic_v3_cpu_if *cpu_if = &vcpu->arch.vgic_cpu.vgic_v3;
+ u64 val;
+ u32 max_lr_idx, nr_pri_bits;
+
+ /*
+ * VFIQEn is RES1 if ICC_SRE_EL1.SRE is 1. This causes a
+ * Group0 interrupt (as generated in GICv2 mode) to be
+ * delivered as a FIQ to the guest, with potentially fatal
+ * consequences. So we must make sure that ICC_SRE_EL1 has
+ * been actually programmed with the value we want before
+ * starting to mess with the rest of the GIC.
+ */
+ write_gicreg(cpu_if->vgic_sre, ICC_SRE_EL1);
+ isb();
+
+ write_gicreg(cpu_if->vgic_hcr, ICH_HCR_EL2);
+ write_gicreg(cpu_if->vgic_vmcr, ICH_VMCR_EL2);
+
+ val = read_gicreg(ICH_VTR_EL2);
+ max_lr_idx = vtr_to_max_lr_idx(val);
+ nr_pri_bits = vtr_to_nr_pri_bits(val);
+
+ switch (nr_pri_bits) {
+ case 7:
+ write_gicreg(cpu_if->vgic_ap1r[3], ICH_AP1R3_EL2);
+ write_gicreg(cpu_if->vgic_ap1r[2], ICH_AP1R2_EL2);
+ case 6:
+ write_gicreg(cpu_if->vgic_ap1r[1], ICH_AP1R1_EL2);
+ default:
+ write_gicreg(cpu_if->vgic_ap1r[0], ICH_AP1R0_EL2);
+ }
+
+ switch (nr_pri_bits) {
+ case 7:
+ write_gicreg(cpu_if->vgic_ap0r[3], ICH_AP0R3_EL2);
+ write_gicreg(cpu_if->vgic_ap0r[2], ICH_AP0R2_EL2);
+ case 6:
+ write_gicreg(cpu_if->vgic_ap0r[1], ICH_AP0R1_EL2);
+ default:
+ write_gicreg(cpu_if->vgic_ap0r[0], ICH_AP0R0_EL2);
+ }
+
+ switch (max_lr_idx) {
+ case 15:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(15)], ICH_LR15_EL2);
+ case 14:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(14)], ICH_LR14_EL2);
+ case 13:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(13)], ICH_LR13_EL2);
+ case 12:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(12)], ICH_LR12_EL2);
+ case 11:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(11)], ICH_LR11_EL2);
+ case 10:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(10)], ICH_LR10_EL2);
+ case 9:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(9)], ICH_LR9_EL2);
+ case 8:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(8)], ICH_LR8_EL2);
+ case 7:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(7)], ICH_LR7_EL2);
+ case 6:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(6)], ICH_LR6_EL2);
+ case 5:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(5)], ICH_LR5_EL2);
+ case 4:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(4)], ICH_LR4_EL2);
+ case 3:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(3)], ICH_LR3_EL2);
+ case 2:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(2)], ICH_LR2_EL2);
+ case 1:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(1)], ICH_LR1_EL2);
+ case 0:
+ write_gicreg(cpu_if->vgic_lr[VGIC_V3_LR_INDEX(0)], ICH_LR0_EL2);
+ }
+
+ /*
+ * Ensures that the above will have reached the
+ * (re)distributors. This ensure the guest will read the
+ * correct values from the memory-mapped interface.
+ */
+ isb();
+ dsb(sy);
+
+ /*
+ * Prevent the guest from touching the GIC system registers if
+ * SRE isn't enabled for GICv3 emulation.
+ */
+ if (!cpu_if->vgic_sre) {
+ write_gicreg(read_gicreg(ICC_SRE_EL2) & ~ICC_SRE_EL2_ENABLE,
+ ICC_SRE_EL2);
+ }
+}
+
+u64 __hyp_text __vgic_v3_read_ich_vtr_el2(void)
+{
+ return read_gicreg(ICH_VTR_EL2);
+}
--
2.1.4
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