| Message ID | 1396435347-20056-11-git-send-email-anup.patel@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Apr 2, 2014 at 5:42 AM, Anup Patel <anup.patel@linaro.org> wrote: > As-per PSCI v0.2, the source CPU provides physical address of > "entry point" and "context id" for starting a target CPU. Also, > if target CPU is already running then we should return ALREADY_ON. > > Current emulation of CPU_ON function does not consider physical > address of "context id" and returns INVALID_PARAMETERS if target > CPU is already running. > > This patch updates kvm_psci_vcpu_on() such that it works for both > PSCI v0.1 and PSCI v0.2. > > Signed-off-by: Anup Patel <anup.patel@linaro.org> > Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> > Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> > --- > arch/arm/kvm/psci.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c > index d8335da..fdbd829 100644 > --- a/arch/arm/kvm/psci.c > +++ b/arch/arm/kvm/psci.c > @@ -101,6 +109,8 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) > kvm_vcpu_set_be(vcpu); > > *vcpu_pc(vcpu) = target_pc; > + if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1) > + *vcpu_reg(vcpu, 0) = context_id; This could be done unconditionally. The register value is undefined for 0.1, so whatever was in r3/x3 meets that requirement. Rob
On 2 April 2014 18:42, Rob Herring <robherring2@gmail.com> wrote: > On Wed, Apr 2, 2014 at 5:42 AM, Anup Patel <anup.patel@linaro.org> wrote: >> As-per PSCI v0.2, the source CPU provides physical address of >> "entry point" and "context id" for starting a target CPU. Also, >> if target CPU is already running then we should return ALREADY_ON. >> >> Current emulation of CPU_ON function does not consider physical >> address of "context id" and returns INVALID_PARAMETERS if target >> CPU is already running. >> >> This patch updates kvm_psci_vcpu_on() such that it works for both >> PSCI v0.1 and PSCI v0.2. >> >> Signed-off-by: Anup Patel <anup.patel@linaro.org> >> Signed-off-by: Pranavkumar Sawargaonkar <pranavkumar@linaro.org> >> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> >> --- >> arch/arm/kvm/psci.c | 12 +++++++++++- >> 1 file changed, 11 insertions(+), 1 deletion(-) >> >> diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c >> index d8335da..fdbd829 100644 >> --- a/arch/arm/kvm/psci.c >> +++ b/arch/arm/kvm/psci.c > > >> @@ -101,6 +109,8 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) >> kvm_vcpu_set_be(vcpu); >> >> *vcpu_pc(vcpu) = target_pc; >> + if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1) >> + *vcpu_reg(vcpu, 0) = context_id; > > This could be done unconditionally. The register value is undefined > for 0.1, so whatever was in r3/x3 meets that requirement. I had similar thought when I first updated this but then I was not sure if PSCI v0.1 assumes this register to be undefined. Let me update this unconditionally as-per your suggestion and put a comment here. > > Rob -- Anup
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c index d8335da..fdbd829 100644 --- a/arch/arm/kvm/psci.c +++ b/arch/arm/kvm/psci.c @@ -63,6 +63,7 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) struct kvm_vcpu *vcpu = NULL, *tmp; wait_queue_head_t *wq; unsigned long cpu_id; + unsigned long context_id; unsigned long mpidr; phys_addr_t target_pc; int i; @@ -83,10 +84,17 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) * Make sure the caller requested a valid CPU and that the CPU is * turned off. */ - if (!vcpu || !vcpu->arch.pause) + if (!vcpu) return PSCI_RET_INVALID_PARAMS; + if (!vcpu->arch.pause) { + if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1) + return PSCI_RET_ALREADY_ON; + else + return PSCI_RET_INVALID_PARAMS; + } target_pc = *vcpu_reg(source_vcpu, 2); + context_id = *vcpu_reg(source_vcpu, 3); kvm_reset_vcpu(vcpu); @@ -101,6 +109,8 @@ static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) kvm_vcpu_set_be(vcpu); *vcpu_pc(vcpu) = target_pc; + if (kvm_psci_version(source_vcpu) != KVM_ARM_PSCI_0_1) + *vcpu_reg(vcpu, 0) = context_id; vcpu->arch.pause = false; smp_mb(); /* Make sure the above is visible */