diff mbox

[v2,2/3] ARM/ARM64: KVM: Add support for PSCI v0.2 emulation

Message ID 1391078479-7406-3-git-send-email-anup.patel@linaro.org
State New
Headers show

Commit Message

Anup Patel Jan. 30, 2014, 10:41 a.m. UTC 
Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to
VCPUs. This patch extends current in-kernel PSCI emulation to provide
PSCI v0.2 interface to VCPUs.

By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for
keeping the ABI backward-compatible.

To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or
KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU
init using KVM_ARM_VCPU_INIT ioctl.

Signed-off-by: Anup Patel <anup.patel@linaro.org>
Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
---
 arch/arm/include/asm/kvm_host.h   |    2 +-
 arch/arm/include/asm/kvm_psci.h   |    4 ++
 arch/arm/include/uapi/asm/kvm.h   |   35 ++++++++++++++-
 arch/arm/kvm/arm.c                |    1 +
 arch/arm/kvm/psci.c               |   85 +++++++++++++++++++++++++++++++------
 arch/arm64/include/asm/kvm_host.h |    2 +-
 arch/arm64/include/asm/kvm_psci.h |    4 ++
 arch/arm64/include/uapi/asm/kvm.h |   35 ++++++++++++++-
 8 files changed, 152 insertions(+), 16 deletions(-)

Comments

Christoffer Dall Feb. 2, 2014, 4:04 a.m. UTC | #1 
On Thu, Jan 30, 2014 at 04:11:18PM +0530, Anup Patel wrote:
> Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to
> VCPUs. This patch extends current in-kernel PSCI emulation to provide
> PSCI v0.2 interface to VCPUs.
> 
> By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for
> keeping the ABI backward-compatible.
> 
> To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or
> KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU
> init using KVM_ARM_VCPU_INIT ioctl.
> 
> Signed-off-by: Anup Patel <anup.patel@linaro.org>
> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org>
> ---
>  arch/arm/include/asm/kvm_host.h   |    2 +-
>  arch/arm/include/asm/kvm_psci.h   |    4 ++
>  arch/arm/include/uapi/asm/kvm.h   |   35 ++++++++++++++-
>  arch/arm/kvm/arm.c                |    1 +
>  arch/arm/kvm/psci.c               |   85 +++++++++++++++++++++++++++++++------
>  arch/arm64/include/asm/kvm_host.h |    2 +-
>  arch/arm64/include/asm/kvm_psci.h |    4 ++
>  arch/arm64/include/uapi/asm/kvm.h |   35 ++++++++++++++-
>  8 files changed, 152 insertions(+), 16 deletions(-)
> 
> diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
> index bce6d32..dc4e3ed 100644
> --- a/arch/arm/include/asm/kvm_host.h
> +++ b/arch/arm/include/asm/kvm_host.h
> @@ -36,7 +36,7 @@
>  #define KVM_COALESCED_MMIO_PAGE_OFFSET 1
>  #define KVM_HAVE_ONE_REG
>  
> -#define KVM_VCPU_MAX_FEATURES 1
> +#define KVM_VCPU_MAX_FEATURES 2
>  
>  #include <kvm/arm_vgic.h>
>  
> diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h
> index 9a83d98..4c0e3e1 100644
> --- a/arch/arm/include/asm/kvm_psci.h
> +++ b/arch/arm/include/asm/kvm_psci.h
> @@ -18,6 +18,10 @@
>  #ifndef __ARM_KVM_PSCI_H__
>  #define __ARM_KVM_PSCI_H__
>  
> +#define KVM_ARM_PSCI_0_1	1
> +#define KVM_ARM_PSCI_0_2	2
> +
> +int kvm_psci_version(struct kvm_vcpu *vcpu);
>  bool kvm_psci_call(struct kvm_vcpu *vcpu);
>  
>  #endif /* __ARM_KVM_PSCI_H__ */
> diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
> index c498b60..bf860e2 100644
> --- a/arch/arm/include/uapi/asm/kvm.h
> +++ b/arch/arm/include/uapi/asm/kvm.h
> @@ -83,6 +83,7 @@ struct kvm_regs {
>  #define KVM_VGIC_V2_CPU_SIZE		0x2000
>  
>  #define KVM_ARM_VCPU_POWER_OFF		0 /* CPU is started in OFF state */
> +#define KVM_ARM_VCPU_PSCI_0_2		1 /* CPU uses PSCI v0.2 */
>  
>  struct kvm_vcpu_init {
>  	__u32 target;
> @@ -164,7 +165,7 @@ struct kvm_arch_memory_slot {
>  /* Highest supported SPI, from VGIC_NR_IRQS */
>  #define KVM_ARM_IRQ_GIC_MAX		127
>  
> -/* PSCI interface */
> +/* PSCI v0.1 interface */
>  #define KVM_PSCI_FN_BASE		0x95c1ba5e
>  #define KVM_PSCI_FN(n)			(KVM_PSCI_FN_BASE + (n))
>  
> @@ -173,9 +174,41 @@ struct kvm_arch_memory_slot {
>  #define KVM_PSCI_FN_CPU_ON		KVM_PSCI_FN(2)
>  #define KVM_PSCI_FN_MIGRATE		KVM_PSCI_FN(3)
>  
> +/* PSCI v0.2 interface */
> +#define KVM_PSCI_0_2_FN_BASE		0x84000000
> +#define KVM_PSCI_0_2_FN(n)		(KVM_PSCI_0_2_FN_BASE + (n))
> +#define KVM_PSCI_0_2_FN64_BASE		0xC4000000
> +#define KVM_PSCI_0_2_FN64(n)		(KVM_PSCI_0_2_FN64_BASE + (n))
> +
> +#define KVM_PSCI_0_2_FN_PSCI_VERSION	KVM_PSCI_0_2_FN(0)
> +#define KVM_PSCI_0_2_FN_CPU_SUSPEND	KVM_PSCI_0_2_FN(1)
> +#define KVM_PSCI_0_2_FN_CPU_OFF		KVM_PSCI_0_2_FN(2)
> +#define KVM_PSCI_0_2_FN_CPU_ON		KVM_PSCI_0_2_FN(3)
> +#define KVM_PSCI_0_2_FN_AFFINITY_INFO	KVM_PSCI_0_2_FN(4)
> +#define KVM_PSCI_0_2_FN_MIGRATE		KVM_PSCI_0_2_FN(5)
> +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
> +					KVM_PSCI_0_2_FN(6)
> +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
> +					KVM_PSCI_0_2_FN(7)
> +#define KVM_PSCI_0_2_FN_SYSTEM_OFF	KVM_PSCI_0_2_FN(8)
> +#define KVM_PSCI_0_2_FN_SYSTEM_RESET	KVM_PSCI_0_2_FN(9)
> +
> +#define KVM_PSCI_0_2_FN64_CPU_SUSPEND	KVM_PSCI_0_2_FN64(1)
> +#define KVM_PSCI_0_2_FN64_CPU_ON	KVM_PSCI_0_2_FN64(3)
> +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO	KVM_PSCI_0_2_FN64(4)
> +#define KVM_PSCI_0_2_FN64_MIGRATE	KVM_PSCI_0_2_FN64(5)
> +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
> +					KVM_PSCI_0_2_FN64(7)
> +
> +/* PSCI return values */
>  #define KVM_PSCI_RET_SUCCESS		0
>  #define KVM_PSCI_RET_NI			((unsigned long)-1)
>  #define KVM_PSCI_RET_INVAL		((unsigned long)-2)
>  #define KVM_PSCI_RET_DENIED		((unsigned long)-3)
> +#define KVM_PSCI_RET_ALREADY_ON		((unsigned long)-4)
> +#define KVM_PSCI_RET_ON_PENDING		((unsigned long)-5)
> +#define KVM_PSCI_RET_INTERNAL_FAILURE	((unsigned long)-6)
> +#define KVM_PSCI_RET_NOT_PRESENT	((unsigned long)-7)
> +#define KVM_PSCI_RET_DISABLED		((unsigned long)-8)
>  
>  #endif /* __ARM_KVM_H__ */
> diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
> index 151eb91..e508125 100644
> --- a/arch/arm/kvm/arm.c
> +++ b/arch/arm/kvm/arm.c
> @@ -193,6 +193,7 @@ int kvm_dev_ioctl_check_extension(long ext)
>  	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
>  	case KVM_CAP_ONE_REG:
>  	case KVM_CAP_ARM_PSCI:
> +	case KVM_CAP_ARM_PSCI_0_2:
>  		r = 1;
>  		break;
>  	case KVM_CAP_COALESCED_MMIO:
> diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c
> index 448f60e..7fdc881 100644
> --- a/arch/arm/kvm/psci.c
> +++ b/arch/arm/kvm/psci.c
> @@ -85,17 +85,57 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
>  	return KVM_PSCI_RET_SUCCESS;
>  }
>  
> -/**
> - * kvm_psci_call - handle PSCI call if r0 value is in range
> - * @vcpu: Pointer to the VCPU struct
> - *
> - * Handle PSCI calls from guests through traps from HVC instructions.
> - * The calling convention is similar to SMC calls to the secure world where
> - * the function number is placed in r0 and this function returns true if the
> - * function number specified in r0 is withing the PSCI range, and false
> - * otherwise.
> - */
> -bool kvm_psci_call(struct kvm_vcpu *vcpu)
> +int kvm_psci_version(struct kvm_vcpu *vcpu)
> +{
> +	if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
> +		return KVM_ARM_PSCI_0_2;
> +
> +	return KVM_ARM_PSCI_0_1;
> +}
> +
> +static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
> +{
> +	unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0);
> +	unsigned long val;
> +
> +	switch (psci_fn) {
> +	case KVM_PSCI_0_2_FN_PSCI_VERSION:
> +		/*
> +		 * Bits[31:16] = Major Version = 0
> +		 * Bits[15:0] = Minor Version = 2
> +		 */
> +		val = 2;
> +		break;
> +	case KVM_PSCI_0_2_FN_CPU_OFF:
> +		kvm_psci_vcpu_off(vcpu);
> +		val = KVM_PSCI_RET_SUCCESS;
> +		break;
> +	case KVM_PSCI_0_2_FN_CPU_ON:
> +	case KVM_PSCI_0_2_FN64_CPU_ON:
> +		val = kvm_psci_vcpu_on(vcpu);
> +		break;
> +	case KVM_PSCI_0_2_FN_CPU_SUSPEND:
> +	case KVM_PSCI_0_2_FN_AFFINITY_INFO:
> +	case KVM_PSCI_0_2_FN_MIGRATE:
> +	case KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
> +	case KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU:
> +	case KVM_PSCI_0_2_FN_SYSTEM_OFF:
> +	case KVM_PSCI_0_2_FN_SYSTEM_RESET:
> +	case KVM_PSCI_0_2_FN64_CPU_SUSPEND:
> +	case KVM_PSCI_0_2_FN64_AFFINITY_INFO:
> +	case KVM_PSCI_0_2_FN64_MIGRATE:
> +	case KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU:
> +		val = KVM_PSCI_RET_NI;
> +		break;
> +	default:
> +		return false;
> +	}
> +
> +	*vcpu_reg(vcpu, 0) = val;
> +	return true;
> +}
> +
> +static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu)
>  {
>  	unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0);
>  	unsigned long val;
> @@ -112,7 +152,6 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu)
>  	case KVM_PSCI_FN_MIGRATE:
>  		val = KVM_PSCI_RET_NI;
>  		break;
> -
>  	default:
>  		return false;
>  	}
> @@ -120,3 +159,25 @@ bool kvm_psci_call(struct kvm_vcpu *vcpu)
>  	*vcpu_reg(vcpu, 0) = val;
>  	return true;
>  }
> +
> +/**
> + * kvm_psci_call - handle PSCI call if r0 value is in range
> + * @vcpu: Pointer to the VCPU struct
> + *
> + * Handle PSCI calls from guests through traps from HVC instructions.
> + * The calling convention is similar to SMC calls to the secure world where
> + * the function number is placed in r0 and this function returns true if the
> + * function number specified in r0 is withing the PSCI range, and false
> + * otherwise.
> + */
> +bool kvm_psci_call(struct kvm_vcpu *vcpu)
> +{
> +	switch (kvm_psci_version(vcpu)) {
> +	case KVM_ARM_PSCI_0_2:
> +		return kvm_psci_0_2_call(vcpu); 
> +	case KVM_ARM_PSCI_0_1:
> +		return kvm_psci_0_1_call(vcpu); 
> +	default:
> +		return false;
> +	};
> +}
> diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
> index 0a1d697..92242ce 100644
> --- a/arch/arm64/include/asm/kvm_host.h
> +++ b/arch/arm64/include/asm/kvm_host.h
> @@ -39,7 +39,7 @@
>  #include <kvm/arm_vgic.h>
>  #include <kvm/arm_arch_timer.h>
>  
> -#define KVM_VCPU_MAX_FEATURES 2
> +#define KVM_VCPU_MAX_FEATURES 3
>  
>  struct kvm_vcpu;
>  int kvm_target_cpu(void);
> diff --git a/arch/arm64/include/asm/kvm_psci.h b/arch/arm64/include/asm/kvm_psci.h
> index e301a48..e25c658 100644
> --- a/arch/arm64/include/asm/kvm_psci.h
> +++ b/arch/arm64/include/asm/kvm_psci.h
> @@ -18,6 +18,10 @@
>  #ifndef __ARM64_KVM_PSCI_H__
>  #define __ARM64_KVM_PSCI_H__
>  
> +#define KVM_ARM_PSCI_0_1	1
> +#define KVM_ARM_PSCI_0_2	2
> +
> +int kvm_psci_version(struct kvm_vcpu *vcpu);
>  bool kvm_psci_call(struct kvm_vcpu *vcpu);
>  
>  #endif /* __ARM64_KVM_PSCI_H__ */
> diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
> index d9f026b..b7555d3 100644
> --- a/arch/arm64/include/uapi/asm/kvm.h
> +++ b/arch/arm64/include/uapi/asm/kvm.h
> @@ -77,6 +77,7 @@ struct kvm_regs {
>  
>  #define KVM_ARM_VCPU_POWER_OFF		0 /* CPU is started in OFF state */
>  #define KVM_ARM_VCPU_EL1_32BIT		1 /* CPU running a 32bit VM */
> +#define KVM_ARM_VCPU_PSCI_0_2		2 /* CPU uses PSCI v0.2 */
>  
>  struct kvm_vcpu_init {
>  	__u32 target;
> @@ -150,7 +151,7 @@ struct kvm_arch_memory_slot {
>  /* Highest supported SPI, from VGIC_NR_IRQS */
>  #define KVM_ARM_IRQ_GIC_MAX		127
>  
> -/* PSCI interface */
> +/* PSCI v0.1 interface */
>  #define KVM_PSCI_FN_BASE		0x95c1ba5e
>  #define KVM_PSCI_FN(n)			(KVM_PSCI_FN_BASE + (n))
>  
> @@ -159,10 +160,42 @@ struct kvm_arch_memory_slot {
>  #define KVM_PSCI_FN_CPU_ON		KVM_PSCI_FN(2)
>  #define KVM_PSCI_FN_MIGRATE		KVM_PSCI_FN(3)
>  
> +/* PSCI v0.2 interface */
> +#define KVM_PSCI_0_2_FN_BASE		0x84000000
> +#define KVM_PSCI_0_2_FN(n)		(KVM_PSCI_0_2_FN_BASE + (n))
> +#define KVM_PSCI_0_2_FN64_BASE		0xC4000000
> +#define KVM_PSCI_0_2_FN64(n)		(KVM_PSCI_0_2_FN64_BASE + (n))
> +
> +#define KVM_PSCI_0_2_FN_PSCI_VERSION	KVM_PSCI_0_2_FN(0)
> +#define KVM_PSCI_0_2_FN_CPU_SUSPEND	KVM_PSCI_0_2_FN(1)
> +#define KVM_PSCI_0_2_FN_CPU_OFF		KVM_PSCI_0_2_FN(2)
> +#define KVM_PSCI_0_2_FN_CPU_ON		KVM_PSCI_0_2_FN(3)
> +#define KVM_PSCI_0_2_FN_AFFINITY_INFO	KVM_PSCI_0_2_FN(4)
> +#define KVM_PSCI_0_2_FN_MIGRATE		KVM_PSCI_0_2_FN(5)
> +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
> +					KVM_PSCI_0_2_FN(6)
> +#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
> +					KVM_PSCI_0_2_FN(7)
> +#define KVM_PSCI_0_2_FN_SYSTEM_OFF	KVM_PSCI_0_2_FN(8)
> +#define KVM_PSCI_0_2_FN_SYSTEM_RESET	KVM_PSCI_0_2_FN(9)
> +
> +#define KVM_PSCI_0_2_FN64_CPU_SUSPEND	KVM_PSCI_0_2_FN64(1)
> +#define KVM_PSCI_0_2_FN64_CPU_ON	KVM_PSCI_0_2_FN64(3)
> +#define KVM_PSCI_0_2_FN64_AFFINITY_INFO	KVM_PSCI_0_2_FN64(4)
> +#define KVM_PSCI_0_2_FN64_MIGRATE	KVM_PSCI_0_2_FN64(5)
> +#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
> +					KVM_PSCI_0_2_FN64(7)
> +
> +/* PSCI return values */
>  #define KVM_PSCI_RET_SUCCESS		0
>  #define KVM_PSCI_RET_NI			((unsigned long)-1)
>  #define KVM_PSCI_RET_INVAL		((unsigned long)-2)
>  #define KVM_PSCI_RET_DENIED		((unsigned long)-3)
> +#define KVM_PSCI_RET_ALREADY_ON		((unsigned long)-4)
> +#define KVM_PSCI_RET_ON_PENDING		((unsigned long)-5)
> +#define KVM_PSCI_RET_INTERNAL_FAILURE	((unsigned long)-6)
> +#define KVM_PSCI_RET_NOT_PRESENT	((unsigned long)-7)
> +#define KVM_PSCI_RET_DISABLED		((unsigned long)-8)
>  
>  #endif
>  
> -- 
> 1.7.9.5
> 

Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Christoffer Dall Feb. 3, 2014, 4:26 p.m. UTC | #2 
On Mon, Feb 03, 2014 at 10:54:09AM +0000, Mark Rutland wrote:
> On Thu, Jan 30, 2014 at 10:41:18AM +0000, Anup Patel wrote:
> > Currently, the in-kernel PSCI emulation provides PSCI v0.1 interface to
> > VCPUs. This patch extends current in-kernel PSCI emulation to provide
> > PSCI v0.2 interface to VCPUs.
> > 
> > By default, ARM/ARM64 KVM will always provide PSCI v0.1 interface for
> > keeping the ABI backward-compatible.
> > 
> > To select PSCI v0.2 interface for VCPUs, the user space (i.e. QEMU or
> > KVMTOOL) will have to set KVM_ARM_VCPU_PSCI_0_2 feature when doing VCPU
> > init using KVM_ARM_VCPU_INIT ioctl.
> 
> I have an issue with this. PSCI 0.2 makes all but two functions (MIGRATE
> and MIGRATE_INFO_CPU_UP) mandatory, and hence not allowed to return
> NOT_SUPPORTED.
> 
> Additionally, for correct behaviour across a kexec in future, we'll
> require AFFINITY_INFO for PSCI 0.2+ systems to determint when a CPU is
> actually dead (and cannot affect the cache hierarchy). I'd very much
> like to make that a hard requirement to ensure correctness.
> 
> I would very much like to see at least trivial implementations of those
> mandatory functions, so that we don't need a
> KVM_ARM_VCPU_PSCI_REALLY_0_2 or similar in future. As it stands this
> series does not implement PSCI 0.2.
> 
I didn't realize that PSCI 0.2 mandates more functions, that should
clearly be implemented first, and the patch series should also be
ordered with first supporting the implementation and then finally
exposing the functionality to user space.

Thanks,
-Christoffer
diff mbox

Patch

diff --git a/arch/arm/include/asm/kvm_host.h b/arch/arm/include/asm/kvm_host.h
index bce6d32..dc4e3ed 100644
--- a/arch/arm/include/asm/kvm_host.h
+++ b/arch/arm/include/asm/kvm_host.h
@@ -36,7 +36,7 @@ 
 #define KVM_COALESCED_MMIO_PAGE_OFFSET 1
 #define KVM_HAVE_ONE_REG
 
-#define KVM_VCPU_MAX_FEATURES 1
+#define KVM_VCPU_MAX_FEATURES 2
 
 #include <kvm/arm_vgic.h>
 
diff --git a/arch/arm/include/asm/kvm_psci.h b/arch/arm/include/asm/kvm_psci.h
index 9a83d98..4c0e3e1 100644
--- a/arch/arm/include/asm/kvm_psci.h
+++ b/arch/arm/include/asm/kvm_psci.h
@@ -18,6 +18,10 @@ 
 #ifndef __ARM_KVM_PSCI_H__
 #define __ARM_KVM_PSCI_H__
 
+#define KVM_ARM_PSCI_0_1	1
+#define KVM_ARM_PSCI_0_2	2
+
+int kvm_psci_version(struct kvm_vcpu *vcpu);
 bool kvm_psci_call(struct kvm_vcpu *vcpu);
 
 #endif /* __ARM_KVM_PSCI_H__ */
diff --git a/arch/arm/include/uapi/asm/kvm.h b/arch/arm/include/uapi/asm/kvm.h
index c498b60..bf860e2 100644
--- a/arch/arm/include/uapi/asm/kvm.h
+++ b/arch/arm/include/uapi/asm/kvm.h
@@ -83,6 +83,7 @@  struct kvm_regs {
 #define KVM_VGIC_V2_CPU_SIZE		0x2000
 
 #define KVM_ARM_VCPU_POWER_OFF		0 /* CPU is started in OFF state */
+#define KVM_ARM_VCPU_PSCI_0_2		1 /* CPU uses PSCI v0.2 */
 
 struct kvm_vcpu_init {
 	__u32 target;
@@ -164,7 +165,7 @@  struct kvm_arch_memory_slot {
 /* Highest supported SPI, from VGIC_NR_IRQS */
 #define KVM_ARM_IRQ_GIC_MAX		127
 
-/* PSCI interface */
+/* PSCI v0.1 interface */
 #define KVM_PSCI_FN_BASE		0x95c1ba5e
 #define KVM_PSCI_FN(n)			(KVM_PSCI_FN_BASE + (n))
 
@@ -173,9 +174,41 @@  struct kvm_arch_memory_slot {
 #define KVM_PSCI_FN_CPU_ON		KVM_PSCI_FN(2)
 #define KVM_PSCI_FN_MIGRATE		KVM_PSCI_FN(3)
 
+/* PSCI v0.2 interface */
+#define KVM_PSCI_0_2_FN_BASE		0x84000000
+#define KVM_PSCI_0_2_FN(n)		(KVM_PSCI_0_2_FN_BASE + (n))
+#define KVM_PSCI_0_2_FN64_BASE		0xC4000000
+#define KVM_PSCI_0_2_FN64(n)		(KVM_PSCI_0_2_FN64_BASE + (n))
+
+#define KVM_PSCI_0_2_FN_PSCI_VERSION	KVM_PSCI_0_2_FN(0)
+#define KVM_PSCI_0_2_FN_CPU_SUSPEND	KVM_PSCI_0_2_FN(1)
+#define KVM_PSCI_0_2_FN_CPU_OFF		KVM_PSCI_0_2_FN(2)
+#define KVM_PSCI_0_2_FN_CPU_ON		KVM_PSCI_0_2_FN(3)
+#define KVM_PSCI_0_2_FN_AFFINITY_INFO	KVM_PSCI_0_2_FN(4)
+#define KVM_PSCI_0_2_FN_MIGRATE		KVM_PSCI_0_2_FN(5)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
+					KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
+					KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF	KVM_PSCI_0_2_FN(8)
+#define KVM_PSCI_0_2_FN_SYSTEM_RESET	KVM_PSCI_0_2_FN(9)
+
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND	KVM_PSCI_0_2_FN64(1)
+#define KVM_PSCI_0_2_FN64_CPU_ON	KVM_PSCI_0_2_FN64(3)
+#define KVM_PSCI_0_2_FN64_AFFINITY_INFO	KVM_PSCI_0_2_FN64(4)
+#define KVM_PSCI_0_2_FN64_MIGRATE	KVM_PSCI_0_2_FN64(5)
+#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
+					KVM_PSCI_0_2_FN64(7)
+
+/* PSCI return values */
 #define KVM_PSCI_RET_SUCCESS		0
 #define KVM_PSCI_RET_NI			((unsigned long)-1)
 #define KVM_PSCI_RET_INVAL		((unsigned long)-2)
 #define KVM_PSCI_RET_DENIED		((unsigned long)-3)
+#define KVM_PSCI_RET_ALREADY_ON		((unsigned long)-4)
+#define KVM_PSCI_RET_ON_PENDING		((unsigned long)-5)
+#define KVM_PSCI_RET_INTERNAL_FAILURE	((unsigned long)-6)
+#define KVM_PSCI_RET_NOT_PRESENT	((unsigned long)-7)
+#define KVM_PSCI_RET_DISABLED		((unsigned long)-8)
 
 #endif /* __ARM_KVM_H__ */
diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 151eb91..e508125 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -193,6 +193,7 @@  int kvm_dev_ioctl_check_extension(long ext)
 	case KVM_CAP_DESTROY_MEMORY_REGION_WORKS:
 	case KVM_CAP_ONE_REG:
 	case KVM_CAP_ARM_PSCI:
+	case KVM_CAP_ARM_PSCI_0_2:
 		r = 1;
 		break;
 	case KVM_CAP_COALESCED_MMIO:
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c
index 448f60e..7fdc881 100644
--- a/arch/arm/kvm/psci.c
+++ b/arch/arm/kvm/psci.c
@@ -85,17 +85,57 @@  static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu)
 	return KVM_PSCI_RET_SUCCESS;
 }
 
-/**
- * kvm_psci_call - handle PSCI call if r0 value is in range
- * @vcpu: Pointer to the VCPU struct
- *
- * Handle PSCI calls from guests through traps from HVC instructions.
- * The calling convention is similar to SMC calls to the secure world where
- * the function number is placed in r0 and this function returns true if the
- * function number specified in r0 is withing the PSCI range, and false
- * otherwise.
- */
-bool kvm_psci_call(struct kvm_vcpu *vcpu)
+int kvm_psci_version(struct kvm_vcpu *vcpu)
+{
+	if (test_bit(KVM_ARM_VCPU_PSCI_0_2, vcpu->arch.features))
+		return KVM_ARM_PSCI_0_2;
+
+	return KVM_ARM_PSCI_0_1;
+}
+
+static bool kvm_psci_0_2_call(struct kvm_vcpu *vcpu)
+{
+	unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0);
+	unsigned long val;
+
+	switch (psci_fn) {
+	case KVM_PSCI_0_2_FN_PSCI_VERSION:
+		/*
+		 * Bits[31:16] = Major Version = 0
+		 * Bits[15:0] = Minor Version = 2
+		 */
+		val = 2;
+		break;
+	case KVM_PSCI_0_2_FN_CPU_OFF:
+		kvm_psci_vcpu_off(vcpu);
+		val = KVM_PSCI_RET_SUCCESS;
+		break;
+	case KVM_PSCI_0_2_FN_CPU_ON:
+	case KVM_PSCI_0_2_FN64_CPU_ON:
+		val = kvm_psci_vcpu_on(vcpu);
+		break;
+	case KVM_PSCI_0_2_FN_CPU_SUSPEND:
+	case KVM_PSCI_0_2_FN_AFFINITY_INFO:
+	case KVM_PSCI_0_2_FN_MIGRATE:
+	case KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
+	case KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU:
+	case KVM_PSCI_0_2_FN_SYSTEM_OFF:
+	case KVM_PSCI_0_2_FN_SYSTEM_RESET:
+	case KVM_PSCI_0_2_FN64_CPU_SUSPEND:
+	case KVM_PSCI_0_2_FN64_AFFINITY_INFO:
+	case KVM_PSCI_0_2_FN64_MIGRATE:
+	case KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU:
+		val = KVM_PSCI_RET_NI;
+		break;
+	default:
+		return false;
+	}
+
+	*vcpu_reg(vcpu, 0) = val;
+	return true;
+}
+
+static bool kvm_psci_0_1_call(struct kvm_vcpu *vcpu)
 {
 	unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0);
 	unsigned long val;
@@ -112,7 +152,6 @@  bool kvm_psci_call(struct kvm_vcpu *vcpu)
 	case KVM_PSCI_FN_MIGRATE:
 		val = KVM_PSCI_RET_NI;
 		break;
-
 	default:
 		return false;
 	}
@@ -120,3 +159,25 @@  bool kvm_psci_call(struct kvm_vcpu *vcpu)
 	*vcpu_reg(vcpu, 0) = val;
 	return true;
 }
+
+/**
+ * kvm_psci_call - handle PSCI call if r0 value is in range
+ * @vcpu: Pointer to the VCPU struct
+ *
+ * Handle PSCI calls from guests through traps from HVC instructions.
+ * The calling convention is similar to SMC calls to the secure world where
+ * the function number is placed in r0 and this function returns true if the
+ * function number specified in r0 is withing the PSCI range, and false
+ * otherwise.
+ */
+bool kvm_psci_call(struct kvm_vcpu *vcpu)
+{
+	switch (kvm_psci_version(vcpu)) {
+	case KVM_ARM_PSCI_0_2:
+		return kvm_psci_0_2_call(vcpu); 
+	case KVM_ARM_PSCI_0_1:
+		return kvm_psci_0_1_call(vcpu); 
+	default:
+		return false;
+	};
+}
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 0a1d697..92242ce 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -39,7 +39,7 @@ 
 #include <kvm/arm_vgic.h>
 #include <kvm/arm_arch_timer.h>
 
-#define KVM_VCPU_MAX_FEATURES 2
+#define KVM_VCPU_MAX_FEATURES 3
 
 struct kvm_vcpu;
 int kvm_target_cpu(void);
diff --git a/arch/arm64/include/asm/kvm_psci.h b/arch/arm64/include/asm/kvm_psci.h
index e301a48..e25c658 100644
--- a/arch/arm64/include/asm/kvm_psci.h
+++ b/arch/arm64/include/asm/kvm_psci.h
@@ -18,6 +18,10 @@ 
 #ifndef __ARM64_KVM_PSCI_H__
 #define __ARM64_KVM_PSCI_H__
 
+#define KVM_ARM_PSCI_0_1	1
+#define KVM_ARM_PSCI_0_2	2
+
+int kvm_psci_version(struct kvm_vcpu *vcpu);
 bool kvm_psci_call(struct kvm_vcpu *vcpu);
 
 #endif /* __ARM64_KVM_PSCI_H__ */
diff --git a/arch/arm64/include/uapi/asm/kvm.h b/arch/arm64/include/uapi/asm/kvm.h
index d9f026b..b7555d3 100644
--- a/arch/arm64/include/uapi/asm/kvm.h
+++ b/arch/arm64/include/uapi/asm/kvm.h
@@ -77,6 +77,7 @@  struct kvm_regs {
 
 #define KVM_ARM_VCPU_POWER_OFF		0 /* CPU is started in OFF state */
 #define KVM_ARM_VCPU_EL1_32BIT		1 /* CPU running a 32bit VM */
+#define KVM_ARM_VCPU_PSCI_0_2		2 /* CPU uses PSCI v0.2 */
 
 struct kvm_vcpu_init {
 	__u32 target;
@@ -150,7 +151,7 @@  struct kvm_arch_memory_slot {
 /* Highest supported SPI, from VGIC_NR_IRQS */
 #define KVM_ARM_IRQ_GIC_MAX		127
 
-/* PSCI interface */
+/* PSCI v0.1 interface */
 #define KVM_PSCI_FN_BASE		0x95c1ba5e
 #define KVM_PSCI_FN(n)			(KVM_PSCI_FN_BASE + (n))
 
@@ -159,10 +160,42 @@  struct kvm_arch_memory_slot {
 #define KVM_PSCI_FN_CPU_ON		KVM_PSCI_FN(2)
 #define KVM_PSCI_FN_MIGRATE		KVM_PSCI_FN(3)
 
+/* PSCI v0.2 interface */
+#define KVM_PSCI_0_2_FN_BASE		0x84000000
+#define KVM_PSCI_0_2_FN(n)		(KVM_PSCI_0_2_FN_BASE + (n))
+#define KVM_PSCI_0_2_FN64_BASE		0xC4000000
+#define KVM_PSCI_0_2_FN64(n)		(KVM_PSCI_0_2_FN64_BASE + (n))
+
+#define KVM_PSCI_0_2_FN_PSCI_VERSION	KVM_PSCI_0_2_FN(0)
+#define KVM_PSCI_0_2_FN_CPU_SUSPEND	KVM_PSCI_0_2_FN(1)
+#define KVM_PSCI_0_2_FN_CPU_OFF		KVM_PSCI_0_2_FN(2)
+#define KVM_PSCI_0_2_FN_CPU_ON		KVM_PSCI_0_2_FN(3)
+#define KVM_PSCI_0_2_FN_AFFINITY_INFO	KVM_PSCI_0_2_FN(4)
+#define KVM_PSCI_0_2_FN_MIGRATE		KVM_PSCI_0_2_FN(5)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_TYPE \
+					KVM_PSCI_0_2_FN(6)
+#define KVM_PSCI_0_2_FN_MIGRATE_INFO_UP_CPU \
+					KVM_PSCI_0_2_FN(7)
+#define KVM_PSCI_0_2_FN_SYSTEM_OFF	KVM_PSCI_0_2_FN(8)
+#define KVM_PSCI_0_2_FN_SYSTEM_RESET	KVM_PSCI_0_2_FN(9)
+
+#define KVM_PSCI_0_2_FN64_CPU_SUSPEND	KVM_PSCI_0_2_FN64(1)
+#define KVM_PSCI_0_2_FN64_CPU_ON	KVM_PSCI_0_2_FN64(3)
+#define KVM_PSCI_0_2_FN64_AFFINITY_INFO	KVM_PSCI_0_2_FN64(4)
+#define KVM_PSCI_0_2_FN64_MIGRATE	KVM_PSCI_0_2_FN64(5)
+#define KVM_PSCI_0_2_FN64_MIGRATE_INFO_UP_CPU \
+					KVM_PSCI_0_2_FN64(7)
+
+/* PSCI return values */
 #define KVM_PSCI_RET_SUCCESS		0
 #define KVM_PSCI_RET_NI			((unsigned long)-1)
 #define KVM_PSCI_RET_INVAL		((unsigned long)-2)
 #define KVM_PSCI_RET_DENIED		((unsigned long)-3)
+#define KVM_PSCI_RET_ALREADY_ON		((unsigned long)-4)
+#define KVM_PSCI_RET_ON_PENDING		((unsigned long)-5)
+#define KVM_PSCI_RET_INTERNAL_FAILURE	((unsigned long)-6)
+#define KVM_PSCI_RET_NOT_PRESENT	((unsigned long)-7)
+#define KVM_PSCI_RET_DISABLED		((unsigned long)-8)
 
 #endif