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Diffstat (limited to 'arch/arm/kvm/psci.c')
| -rw-r--r-- | arch/arm/kvm/psci.c | 332 |
1 files changed, 0 insertions, 332 deletions
diff --git a/arch/arm/kvm/psci.c b/arch/arm/kvm/psci.c deleted file mode 100644 index a08d7a93aebb..000000000000 --- a/arch/arm/kvm/psci.c +++ /dev/null @@ -1,332 +0,0 @@ -/* - * 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/preempt.h> -#include <linux/kvm_host.h> -#include <linux/wait.h> - -#include <asm/cputype.h> -#include <asm/kvm_emulate.h> -#include <asm/kvm_psci.h> -#include <asm/kvm_host.h> - -#include <uapi/linux/psci.h> - -/* - * This is an implementation of the Power State Coordination Interface - * as described in ARM document number ARM DEN 0022A. - */ - -#define AFFINITY_MASK(level) ~((0x1UL << ((level) * MPIDR_LEVEL_BITS)) - 1) - -static unsigned long psci_affinity_mask(unsigned long affinity_level) -{ - if (affinity_level <= 3) - return MPIDR_HWID_BITMASK & AFFINITY_MASK(affinity_level); - - return 0; -} - -static unsigned long kvm_psci_vcpu_suspend(struct kvm_vcpu *vcpu) -{ - /* - * NOTE: For simplicity, we make VCPU suspend emulation to be - * same-as WFI (Wait-for-interrupt) emulation. - * - * This means for KVM the wakeup events are interrupts and - * this is consistent with intended use of StateID as described - * in section 5.4.1 of PSCI v0.2 specification (ARM DEN 0022A). - * - * Further, we also treat power-down request to be same as - * stand-by request as-per section 5.4.2 clause 3 of PSCI v0.2 - * specification (ARM DEN 0022A). This means all suspend states - * for KVM will preserve the register state. - */ - kvm_vcpu_block(vcpu); - - return PSCI_RET_SUCCESS; -} - -static void kvm_psci_vcpu_off(struct kvm_vcpu *vcpu) -{ - vcpu->arch.power_off = true; -} - -static unsigned long kvm_psci_vcpu_on(struct kvm_vcpu *source_vcpu) -{ - struct kvm *kvm = source_vcpu->kvm; - struct kvm_vcpu *vcpu = NULL; - struct swait_queue_head *wq; - unsigned long cpu_id; - unsigned long context_id; - phys_addr_t target_pc; - - cpu_id = vcpu_get_reg(source_vcpu, 1) & MPIDR_HWID_BITMASK; - if (vcpu_mode_is_32bit(source_vcpu)) - cpu_id &= ~((u32) 0); - - vcpu = kvm_mpidr_to_vcpu(kvm, cpu_id); - - /* - * Make sure the caller requested a valid CPU and that the CPU is - * turned off. - */ - if (!vcpu) - return PSCI_RET_INVALID_PARAMS; - if (!vcpu->arch.power_off) { - 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_get_reg(source_vcpu, 2); - context_id = vcpu_get_reg(source_vcpu, 3); - - 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); - } - - /* Propagate caller endianness */ - if (kvm_vcpu_is_be(source_vcpu)) - kvm_vcpu_set_be(vcpu); - - *vcpu_pc(vcpu) = target_pc; - /* - * NOTE: We always update r0 (or x0) because for PSCI v0.1 - * the general puspose registers are undefined upon CPU_ON. - */ - vcpu_set_reg(vcpu, 0, context_id); - vcpu->arch.power_off = false; - smp_mb(); /* Make sure the above is visible */ - - wq = kvm_arch_vcpu_wq(vcpu); - swake_up(wq); - - return PSCI_RET_SUCCESS; -} - -static unsigned long kvm_psci_vcpu_affinity_info(struct kvm_vcpu *vcpu) -{ - int i, matching_cpus = 0; - unsigned long mpidr; - unsigned long target_affinity; - unsigned long target_affinity_mask; - unsigned long lowest_affinity_level; - struct kvm *kvm = vcpu->kvm; - struct kvm_vcpu *tmp; - - target_affinity = vcpu_get_reg(vcpu, 1); - lowest_affinity_level = vcpu_get_reg(vcpu, 2); - - /* Determine target affinity mask */ - target_affinity_mask = psci_affinity_mask(lowest_affinity_level); - if (!target_affinity_mask) - return PSCI_RET_INVALID_PARAMS; - - /* Ignore other bits of target affinity */ - target_affinity &= target_affinity_mask; - - /* - * If one or more VCPU matching target affinity are running - * then ON else OFF - */ - kvm_for_each_vcpu(i, tmp, kvm) { - mpidr = kvm_vcpu_get_mpidr_aff(tmp); - if ((mpidr & target_affinity_mask) == target_affinity) { - matching_cpus++; - if (!tmp->arch.power_off) - return PSCI_0_2_AFFINITY_LEVEL_ON; - } - } - - if (!matching_cpus) - return PSCI_RET_INVALID_PARAMS; - - return PSCI_0_2_AFFINITY_LEVEL_OFF; -} - -static void kvm_prepare_system_event(struct kvm_vcpu *vcpu, u32 type) -{ - int i; - struct kvm_vcpu *tmp; - - /* - * The KVM ABI specifies that a system event exit may call KVM_RUN - * again and may perform shutdown/reboot at a later time that when the - * actual request is made. Since we are implementing PSCI and a - * caller of PSCI reboot and shutdown expects that the system shuts - * down or reboots immediately, let's make sure that VCPUs are not run - * after this call is handled and before the VCPUs have been - * re-initialized. - */ - kvm_for_each_vcpu(i, tmp, vcpu->kvm) { - tmp->arch.power_off = true; - kvm_vcpu_kick(tmp); - } - - memset(&vcpu->run->system_event, 0, sizeof(vcpu->run->system_event)); - vcpu->run->system_event.type = type; - vcpu->run->exit_reason = KVM_EXIT_SYSTEM_EVENT; -} - -static void kvm_psci_system_off(struct kvm_vcpu *vcpu) -{ - kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_SHUTDOWN); -} - -static void kvm_psci_system_reset(struct kvm_vcpu *vcpu) -{ - kvm_prepare_system_event(vcpu, KVM_SYSTEM_EVENT_RESET); -} - -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 int kvm_psci_0_2_call(struct kvm_vcpu *vcpu) -{ - struct kvm *kvm = vcpu->kvm; - unsigned long psci_fn = vcpu_get_reg(vcpu, 0) & ~((u32) 0); - unsigned long val; - int ret = 1; - - switch (psci_fn) { - case PSCI_0_2_FN_PSCI_VERSION: - /* - * Bits[31:16] = Major Version = 0 - * Bits[15:0] = Minor Version = 2 - */ - val = 2; - break; - case PSCI_0_2_FN_CPU_SUSPEND: - case PSCI_0_2_FN64_CPU_SUSPEND: - val = kvm_psci_vcpu_suspend(vcpu); - break; - case PSCI_0_2_FN_CPU_OFF: - kvm_psci_vcpu_off(vcpu); - val = PSCI_RET_SUCCESS; - break; - case PSCI_0_2_FN_CPU_ON: - case PSCI_0_2_FN64_CPU_ON: - mutex_lock(&kvm->lock); - val = kvm_psci_vcpu_on(vcpu); - mutex_unlock(&kvm->lock); - break; - case PSCI_0_2_FN_AFFINITY_INFO: - case PSCI_0_2_FN64_AFFINITY_INFO: - val = kvm_psci_vcpu_affinity_info(vcpu); - break; - case PSCI_0_2_FN_MIGRATE_INFO_TYPE: - /* - * Trusted OS is MP hence does not require migration - * or - * Trusted OS is not present - */ - val = PSCI_0_2_TOS_MP; - break; - case PSCI_0_2_FN_SYSTEM_OFF: - kvm_psci_system_off(vcpu); - /* - * We should'nt be going back to guest VCPU after - * receiving SYSTEM_OFF request. - * - * If user space accidently/deliberately resumes - * guest VCPU after SYSTEM_OFF request then guest - * VCPU should see internal failure from PSCI return - * value. To achieve this, we preload r0 (or x0) with - * PSCI return value INTERNAL_FAILURE. - */ - val = PSCI_RET_INTERNAL_FAILURE; - ret = 0; - break; - case PSCI_0_2_FN_SYSTEM_RESET: - kvm_psci_system_reset(vcpu); - /* - * Same reason as SYSTEM_OFF for preloading r0 (or x0) - * with PSCI return value INTERNAL_FAILURE. - */ - val = PSCI_RET_INTERNAL_FAILURE; - ret = 0; - break; - default: - val = PSCI_RET_NOT_SUPPORTED; - break; - } - - vcpu_set_reg(vcpu, 0, val); - return ret; -} - -static int kvm_psci_0_1_call(struct kvm_vcpu *vcpu) -{ - struct kvm *kvm = vcpu->kvm; - unsigned long psci_fn = vcpu_get_reg(vcpu, 0) & ~((u32) 0); - unsigned long val; - - switch (psci_fn) { - case KVM_PSCI_FN_CPU_OFF: - kvm_psci_vcpu_off(vcpu); - val = PSCI_RET_SUCCESS; - break; - case KVM_PSCI_FN_CPU_ON: - mutex_lock(&kvm->lock); - val = kvm_psci_vcpu_on(vcpu); - mutex_unlock(&kvm->lock); - break; - default: - val = PSCI_RET_NOT_SUPPORTED; - break; - } - - vcpu_set_reg(vcpu, 0, val); - return 1; -} - -/** - * 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. - * - * This function returns: > 0 (success), 0 (success but exit to user - * space), and < 0 (errors) - * - * Errors: - * -EINVAL: Unrecognized PSCI function - */ -int 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 -EINVAL; - }; -} |