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 */ 39 static 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 44 static 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 49 static const struct kvm_irq_level default_vtimer_irq = { 50 .irq = 27, 51 .level = 1, 52 }; 53 54 static 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 */ 68 int 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 default: 90 r = 0; 91 } 92 93 return r; 94 } 95 96 /** 97 * kvm_reset_vcpu - sets core registers and sys_regs to reset value 98 * @vcpu: The VCPU pointer 99 * 100 * This function finds the right table above and sets the registers on 101 * the virtual CPU struct to their architecturally defined reset 102 * values. 103 */ 104 int kvm_reset_vcpu(struct kvm_vcpu *vcpu) 105 { 106 const struct kvm_irq_level *cpu_vtimer_irq; 107 const struct kvm_regs *cpu_reset; 108 109 switch (vcpu->arch.target) { 110 default: 111 if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) { 112 if (!cpu_has_32bit_el1()) 113 return -EINVAL; 114 cpu_reset = &default_regs_reset32; 115 } else { 116 cpu_reset = &default_regs_reset; 117 } 118 119 cpu_vtimer_irq = &default_vtimer_irq; 120 break; 121 } 122 123 /* Reset core registers */ 124 memcpy(vcpu_gp_regs(vcpu), cpu_reset, sizeof(*cpu_reset)); 125 126 /* Reset system registers */ 127 kvm_reset_sys_regs(vcpu); 128 129 /* Reset PMU */ 130 kvm_pmu_vcpu_reset(vcpu); 131 132 /* Reset timer */ 133 return kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq); 134 } 135