[PATCH 07/10] ARM: KVM: VGIC control interface world switch

Christoffer Dall
2012-09-15T15:38:07Z

Enable the VGIC control interface to be save-restored on world switch.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Christoffer Dall <c.dall@virtualopensystems.com>
---
arch/arm/include/asm/kvm_arm.h | 12 +++++++
arch/arm/kernel/asm-offsets.c | 12 +++++++
arch/arm/kvm/interrupts.S | 68 ++++++++++++++++++++++++++++++++++++++++
3 files changed, 92 insertions(+)

diff --git a/arch/arm/include/asm/kvm_arm.h b/arch/arm/include/asm/kvm_arm.h
index 21cb240..e01c7d9 100644
--- a/arch/arm/include/asm/kvm_arm.h
+++ b/arch/arm/include/asm/kvm_arm.h
@@ -194,4 +194,16 @@
#define HSR_EC_DABT (0x24)
#define HSR_EC_DABT_HYP (0x25)

+/* GICH offsets */
+#define GICH_HCR 0x0
+#define GICH_VTR 0x4
+#define GICH_VMCR 0x8
+#define GICH_MISR 0x10
+#define GICH_EISR0 0x20
+#define GICH_EISR1 0x24
+#define GICH_ELRSR0 0x30
+#define GICH_ELRSR1 0x34
+#define GICH_APR 0xf0
+#define GICH_LR0 0x100
+
#endif /* __ARM_KVM_ARM_H__ */
diff --git a/arch/arm/kernel/asm-offsets.c b/arch/arm/kernel/asm-offsets.c
index cd8fc86..b277b7a 100644
--- a/arch/arm/kernel/asm-offsets.c
+++ b/arch/arm/kernel/asm-offsets.c
@@ -186,6 +186,18 @@ int main(void)
DEFINE(VCPU_HIFAR, offsetof(struct kvm_vcpu, arch.hifar));
DEFINE(VCPU_HPFAR, offsetof(struct kvm_vcpu, arch.hpfar));
DEFINE(VCPU_HYP_PC, offsetof(struct kvm_vcpu, arch.hyp_pc));
+#ifdef CONFIG_KVM_ARM_VGIC
+ DEFINE(VCPU_VGIC_CPU, offsetof(struct kvm_vcpu, arch.vgic_cpu));
+ DEFINE(VGIC_CPU_HCR, offsetof(struct vgic_cpu, vgic_hcr));
+ DEFINE(VGIC_CPU_VMCR, offsetof(struct vgic_cpu, vgic_vmcr));
+ DEFINE(VGIC_CPU_MISR, offsetof(struct vgic_cpu, vgic_misr));
+ DEFINE(VGIC_CPU_EISR, offsetof(struct vgic_cpu, vgic_eisr));
+ DEFINE(VGIC_CPU_ELRSR, offsetof(struct vgic_cpu, vgic_elrsr));
+ DEFINE(VGIC_CPU_APR, offsetof(struct vgic_cpu, vgic_apr));
+ DEFINE(VGIC_CPU_LR, offsetof(struct vgic_cpu, vgic_lr));
+ DEFINE(VGIC_CPU_NR_LR, offsetof(struct vgic_cpu, nr_lr));
+ DEFINE(KVM_VGIC_VCTRL, offsetof(struct kvm, arch.vgic.vctrl_base));
+#endif
DEFINE(KVM_VTTBR, offsetof(struct kvm, arch.vttbr));
#endif
return 0;
diff --git a/arch/arm/kvm/interrupts.S b/arch/arm/kvm/interrupts.S
index dad9df7..bf0f83f 100644
--- a/arch/arm/kvm/interrupts.S
+++ b/arch/arm/kvm/interrupts.S
@@ -316,6 +316,45 @@ ENDPROC(__kvm_flush_vm_context)
* @vcpup: Register pointing to VCPU struct
*/
.macro save_vgic_state vcpup
+#ifdef CONFIG_KVM_ARM_VGIC
+ /* Get VGIC VCTRL base into r2 */
+ ldr r2, [\vcpup, #VCPU_KVM]
+ ldr r2, [r2, #KVM_VGIC_VCTRL]
+ cmp r2, #0
+ beq 2f
+
+ /* Compute the address of struct vgic_cpu */
+ add r11, \vcpup, #VCPU_VGIC_CPU
+
+ /* Save all interesting registers */
+ ldr r3, [r2, #GICH_HCR]
+ ldr r4, [r2, #GICH_VMCR]
+ ldr r5, [r2, #GICH_MISR]
+ ldr r6, [r2, #GICH_EISR0]
+ ldr r7, [r2, #GICH_EISR1]
+ ldr r8, [r2, #GICH_ELRSR0]
+ ldr r9, [r2, #GICH_ELRSR1]
+ ldr r10, [r2, #GICH_APR]
+
+ str r3, [r11, #VGIC_CPU_HCR]
+ str r4, [r11, #VGIC_CPU_VMCR]
+ str r5, [r11, #VGIC_CPU_MISR]
+ str r6, [r11, #VGIC_CPU_EISR]
+ str r7, [r11, #(VGIC_CPU_EISR + 4)]
+ str r8, [r11, #VGIC_CPU_ELRSR]
+ str r9, [r11, #(VGIC_CPU_ELRSR + 4)]
+ str r10, [r11, #VGIC_CPU_APR]
+
+ /* Save list registers */
+ add r2, r2, #GICH_LR0
+ add r3, r11, #VGIC_CPU_LR
+ ldr r4, [r11, #VGIC_CPU_NR_LR]
+1: ldr r6, [r2], #4
+ str r6, [r3], #4
+ subs r4, r4, #1
+ bne 1b
+2:
+#endif
.endm

/*
@@ -323,6 +362,35 @@ ENDPROC(__kvm_flush_vm_context)
* @vcpup: Register pointing to VCPU struct
*/
.macro restore_vgic_state vcpup
+#ifdef CONFIG_KVM_ARM_VGIC
+ /* Get VGIC VCTRL base into r2 */
+ ldr r2, [\vcpup, #VCPU_KVM]
+ ldr r2, [r2, #KVM_VGIC_VCTRL]
+ cmp r2, #0
+ beq 2f
+
+ /* Compute the address of struct vgic_cpu */
+ add r11, \vcpup, #VCPU_VGIC_CPU
+
+ /* We only restore a minimal set of registers */
+ ldr r3, [r11, #VGIC_CPU_HCR]
+ ldr r4, [r11, #VGIC_CPU_VMCR]
+ ldr r8, [r11, #VGIC_CPU_APR]
+
+ str r3, [r2, #GICH_HCR]
+ str r4, [r2, #GICH_VMCR]
+ str r8, [r2, #GICH_APR]
+
+ /* Restore list registers */
+ add r2, r2, #GICH_LR0
+ add r3, r11, #VGIC_CPU_LR
+ ldr r4, [r11, #VGIC_CPU_NR_LR]
+1: ldr r6, [r3], #4
+ str r6, [r2], #4
+ subs r4, r4, #1
+ bne 1b
+2:
+#endif
.endm

/* Configures the HSTR (Hyp System Trap Register) on entry/return