LXR linux/arch/arm64/kvm/reset.c

   1/*
   2 * Copyright (C) 2012,2013 - ARM Ltd
   3 * Author: Marc Zyngier <marc.zyngier@arm.com>
   4 *
   5 * Derived from arch/arm/kvm/reset.c
   6 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
   7 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
   8 *
   9 * This program is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License, version 2, as
  11 * published by the Free Software Foundation.
  12 *
  13 * This program is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20 */
  21
  22#include <linux/errno.h>
  23#include <linux/kvm_host.h>
  24#include <linux/kvm.h>
  25#include <linux/hw_breakpoint.h>
  26
  27#include <kvm/arm_arch_timer.h>
  28
  29#include <asm/cputype.h>
  30#include <asm/ptrace.h>
  31#include <asm/kvm_arm.h>
  32#include <asm/kvm_asm.h>
  33#include <asm/kvm_coproc.h>
  34#include <asm/kvm_mmu.h>
  35
  36/*
  37 * ARMv8 Reset Values
  38 */
  39static const struct kvm_regs default_regs_reset = {
  40        .regs.pstate = (PSR_MODE_EL1h | PSR_A_BIT | PSR_I_BIT |
  41                        PSR_F_BIT | PSR_D_BIT),
  42};
  43
  44static const struct kvm_regs default_regs_reset32 = {
  45        .regs.pstate = (COMPAT_PSR_MODE_SVC | COMPAT_PSR_A_BIT |
  46                        COMPAT_PSR_I_BIT | COMPAT_PSR_F_BIT),
  47};
  48
  49static const struct kvm_irq_level default_vtimer_irq = {
  50        .irq    = 27,
  51        .level  = 1,
  52};
  53
  54static bool cpu_has_32bit_el1(void)
  55{
  56        u64 pfr0;
  57
  58        pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1);
  59        return !!(pfr0 & 0x20);
  60}
  61
  62/**
  63 * kvm_arch_dev_ioctl_check_extension
  64 *
  65 * We currently assume that the number of HW registers is uniform
  66 * across all CPUs (see cpuinfo_sanity_check).
  67 */
  68int kvm_arch_dev_ioctl_check_extension(struct kvm *kvm, long ext)
  69{
  70        int r;
  71
  72        switch (ext) {
  73        case KVM_CAP_ARM_EL1_32BIT:
  74                r = cpu_has_32bit_el1();
  75                break;
  76        case KVM_CAP_GUEST_DEBUG_HW_BPS:
  77                r = get_num_brps();
  78                break;
  79        case KVM_CAP_GUEST_DEBUG_HW_WPS:
  80                r = get_num_wrps();
  81                break;
  82        case KVM_CAP_ARM_PMU_V3:
  83                r = kvm_arm_support_pmu_v3();
  84                break;
  85        case KVM_CAP_SET_GUEST_DEBUG:
  86        case KVM_CAP_VCPU_ATTRIBUTES:
  87                r = 1;
  88                break;
  89        case KVM_CAP_MSI_DEVID:
  90                if (!kvm)
  91                        r = -EINVAL;
  92                else
  93                        r = kvm->arch.vgic.msis_require_devid;
  94                break;
  95        default:
  96                r = 0;
  97        }
  98
  99        return r;
 100}
 101
 102/**
 103 * kvm_reset_vcpu - sets core registers and sys_regs to reset value
 104 * @vcpu: The VCPU pointer
 105 *
 106 * This function finds the right table above and sets the registers on
 107 * the virtual CPU struct to their architecturally defined reset
 108 * values.
 109 */
 110int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
 111{
 112        const struct kvm_irq_level *cpu_vtimer_irq;
 113        const struct kvm_regs *cpu_reset;
 114
 115        switch (vcpu->arch.target) {
 116        default:
 117                if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) {
 118                        if (!cpu_has_32bit_el1())
 119                                return -EINVAL;
 120                        cpu_reset = &default_regs_reset32;
 121                } else {
 122                        cpu_reset = &default_regs_reset;
 123                }
 124
 125                cpu_vtimer_irq = &default_vtimer_irq;
 126                break;
 127        }
 128
 129        /* Reset core registers */
 130        memcpy(vcpu_gp_regs(vcpu), cpu_reset, sizeof(*cpu_reset));
 131
 132        /* Reset system registers */
 133        kvm_reset_sys_regs(vcpu);
 134
 135        /* Reset PMU */
 136        kvm_pmu_vcpu_reset(vcpu);
 137
 138        /* Reset timer */
 139        return kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq);
 140}
 141