[PATCH v4 02/10] ARM/ARM64: KVM: Add base for PSCI v0.2 emulation
Anup Patel
anup at brainfault.org
Fri Feb 7 04:26:23 EST 2014
On Fri, Feb 7, 2014 at 2:37 PM, Jungseok Lee <jays.lee at samsung.com> wrote:
> On Friday, February 07, 2014 5:36 PM, Anup Patel wrote:
>> On Fri, Feb 7, 2014 at 1:58 PM, Jungseok Lee <jays.lee at samsung.com> wrote:
>> > On Thursday, February 06, 2014 8:32 PM, 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 at linaro.org>
>> >> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar at 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 09af149..193ceaf
>> >> 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 ef0c878..9c922d9
>> >> 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;
>> >> @@ -192,7 +193,7 @@ 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))
>> >>
>> >> @@ -201,9 +202,41 @@ 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)
>> >> +
>> >
>> > Hi
>> >
>> > This patch describes PSCI v0.2 specification well. Instead, I have a
>> > question on interface types, not implementation.
>> >
>> > According to PSCI v0.2 document, it does not cover DVFS.
>> > Could I get an idea why DVFS is not supported?
>>
>> PSCI v0.2 only describes few mandatory functions required for being PSCI v0.2 compliant. For rest of
>> the stuff such as DVFS you will need to define your own platform specific PSCI function.
>> (Marc/Mark correct me if I am wrong here?)
>
> It seems that I should change architecture codes if I need other interfaces.
> Under this implementation, I should add my own interface to generic codes,
> such as, arch/arm/include/asm/kvm_psci.h. However, I think that it is not
> acceptable to upstream. If so, is there any place to define a platform
> specific PSCI functions?
Are you trying to emulate your platform specific DVFS PSCI
function for a VM using KVM ARM/ARM64??
If so then arch/arm/kvm/psci.c is not the place for it. All platform
specific PSCI function are to be emulated from user space. KVM
ARM/ARM64 will only emulate HVC-based mandatory PSCI v0.2
functions.
User space emulation of platform specific PSCI functions are
still a TODO item for KVM ARM/ARM64. It will require a
mechanism in KVM ARM/ARM64 to route SMC-based
PSCI function calls to user space (i.e. QEMU or KVMTOOL).
Regards,
Anup
>
> Best Regards
> Jungseok Lee
>
>> Mab be in future some PSCI vX.Y will define standardized PSCI function for DVFS too.
>>
>> Regards,
>> Anup
>>
>> >
>> > Best Regards
>> > Jungseok Lee
>> >
>> >> +/* 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
>> >> 1d8248e..c8a71df 100644
>> >> --- a/arch/arm/kvm/arm.c
>> >> +++ b/arch/arm/kvm/arm.c
>> >> @@ -197,6 +197,7 @@ 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..e4ec4af 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 eaf54a3..cadc318 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;
>> >> @@ -177,7 +178,7 @@ 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))
>> >>
>> >> @@ -186,10 +187,42 @@ 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
>> >>
>> >> _______________________________________________
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>> >> kvmarm at lists.cs.columbia.edu
>> >> https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
>> >
>> > _______________________________________________
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>> > kvmarm at lists.cs.columbia.edu
>> > https://lists.cs.columbia.edu/cucslists/listinfo/kvmarm
>
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