diff options
Diffstat (limited to 'arch/arm/kvm')
-rw-r--r-- | arch/arm/kvm/Makefile | 2 | ||||
-rw-r--r-- | arch/arm/kvm/arm.c | 30 | ||||
-rw-r--r-- | arch/arm/kvm/psci.c | 108 |
3 files changed, 137 insertions, 3 deletions
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile index 1e45cd97a7f..ea27987bd07 100644 --- a/arch/arm/kvm/Makefile +++ b/arch/arm/kvm/Makefile @@ -18,4 +18,4 @@ kvm-arm-y = $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o) obj-y += kvm-arm.o init.o interrupts.o obj-y += arm.o guest.o mmu.o emulate.o reset.o -obj-y += coproc.o coproc_a15.o mmio.o +obj-y += coproc.o coproc_a15.o mmio.o psci.o diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 8680b9ffd2a..2d30e3afdaf 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -43,6 +43,7 @@ #include <asm/kvm_mmu.h> #include <asm/kvm_emulate.h> #include <asm/kvm_coproc.h> +#include <asm/kvm_psci.h> #include <asm/opcodes.h> #ifdef REQUIRES_VIRT @@ -160,6 +161,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_SYNC_MMU: case KVM_CAP_DESTROY_MEMORY_REGION_WORKS: case KVM_CAP_ONE_REG: + case KVM_CAP_ARM_PSCI: r = 1; break; case KVM_CAP_COALESCED_MMIO: @@ -443,14 +445,18 @@ static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) trace_kvm_hvc(*vcpu_pc(vcpu), *vcpu_reg(vcpu, 0), vcpu->arch.hsr & HSR_HVC_IMM_MASK); + if (kvm_psci_call(vcpu)) + return 1; + kvm_inject_undefined(vcpu); return 1; } static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) { - /* We don't support SMC; don't do that. */ - kvm_debug("smc: at %08x", *vcpu_pc(vcpu)); + if (kvm_psci_call(vcpu)) + return 1; + kvm_inject_undefined(vcpu); return 1; } @@ -589,9 +595,26 @@ static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) return 0; vcpu->arch.has_run_once = true; + + /* + * Handle the "start in power-off" case by calling into the + * PSCI code. + */ + if (test_and_clear_bit(KVM_ARM_VCPU_POWER_OFF, vcpu->arch.features)) { + *vcpu_reg(vcpu, 0) = KVM_PSCI_FN_CPU_OFF; + kvm_psci_call(vcpu); + } + return 0; } +static void vcpu_pause(struct kvm_vcpu *vcpu) +{ + wait_queue_head_t *wq = kvm_arch_vcpu_wq(vcpu); + + wait_event_interruptible(*wq, !vcpu->arch.pause); +} + /** * kvm_arch_vcpu_ioctl_run - the main VCPU run function to execute guest code * @vcpu: The VCPU pointer @@ -635,6 +658,9 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) update_vttbr(vcpu->kvm); + if (vcpu->arch.pause) + vcpu_pause(vcpu); + local_irq_disable(); /* diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c new file mode 100644 index 00000000000..7ee5bb7a366 --- /dev/null +++ b/arch/arm/kvm/psci.c @@ -0,0 +1,108 @@ +/* + * Copyright (C) 2012 - ARM Ltd + * Author: Marc Zyngier <marc.zyngier@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/kvm_host.h> +#include <linux/wait.h> + +#include <asm/kvm_emulate.h> +#include <asm/kvm_psci.h> + +/* + * This is an implementation of the Power State Coordination Interface + * as described in ARM document number ARM DEN 0022A. + */ + +static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu) +{ + vcpu->arch.pause = true; +} + +static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) +{ + struct kvm *kvm = source_vcpu->kvm; + struct kvm_vcpu *vcpu; + wait_queue_head_t *wq; + unsigned long cpu_id; + phys_addr_t target_pc; + + cpu_id = *vcpu_reg(source_vcpu, 1); + if (vcpu_mode_is_32bit(source_vcpu)) + cpu_id &= ~((u32) 0); + + if (cpu_id >= atomic_read(&kvm->online_vcpus)) + return KVM_PSCI_RET_INVAL; + + target_pc = *vcpu_reg(source_vcpu, 2); + + vcpu = kvm_get_vcpu(kvm, cpu_id); + + wq = kvm_arch_vcpu_wq(vcpu); + if (!waitqueue_active(wq)) + return KVM_PSCI_RET_INVAL; + + kvm_reset_vcpu(vcpu); + + /* Gracefully handle Thumb2 entry point */ + if (vcpu_mode_is_32bit(vcpu) && (target_pc & 1)) { + target_pc &= ~((phys_addr_t) 1); + vcpu_set_thumb(vcpu); + } + + *vcpu_pc(vcpu) = target_pc; + vcpu->arch.pause = false; + smp_mb(); /* Make sure the above is visible */ + + wake_up_interruptible(wq); + + 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 or SMC 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) +{ + unsigned long psci_fn = *vcpu_reg(vcpu, 0) & ~((u32) 0); + unsigned long val; + + switch (psci_fn) { + case KVM_PSCI_FN_CPU_OFF: + kvm_psci_vcpu_off(vcpu); + val = KVM_PSCI_RET_SUCCESS; + break; + case KVM_PSCI_FN_CPU_ON: + val = kvm_psci_vcpu_on(vcpu); + break; + case KVM_PSCI_FN_CPU_SUSPEND: + case KVM_PSCI_FN_MIGRATE: + val = KVM_PSCI_RET_NI; + break; + + default: + return false; + } + + *vcpu_reg(vcpu, 0) = val; + return true; +} |