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 26 #include <kvm/arm_arch_timer.h> 27 28 #include <asm/cputype.h> 29 #include <asm/ptrace.h> 30 #include <asm/kvm_arm.h> 31 #include <asm/kvm_coproc.h> 32 33 /* 34 * ARMv8 Reset Values 35 */ 36 static const struct kvm_regs default_regs_reset = { 37 .regs.pstate = (PSR_MODE_EL1h | PSR_A_BIT | PSR_I_BIT | 38 PSR_F_BIT | PSR_D_BIT), 39 }; 40 41 static const struct kvm_regs default_regs_reset32 = { 42 .regs.pstate = (COMPAT_PSR_MODE_SVC | COMPAT_PSR_A_BIT | 43 COMPAT_PSR_I_BIT | COMPAT_PSR_F_BIT), 44 }; 45 46 static const struct kvm_irq_level default_vtimer_irq = { 47 .irq = 27, 48 .level = 1, 49 }; 50 51 static bool cpu_has_32bit_el1(void) 52 { 53 u64 pfr0; 54 55 pfr0 = read_cpuid(ID_AA64PFR0_EL1); 56 return !!(pfr0 & 0x20); 57 } 58 59 int kvm_arch_dev_ioctl_check_extension(long ext) 60 { 61 int r; 62 63 switch (ext) { 64 case KVM_CAP_ARM_EL1_32BIT: 65 r = cpu_has_32bit_el1(); 66 break; 67 default: 68 r = 0; 69 } 70 71 return r; 72 } 73 74 /** 75 * kvm_reset_vcpu - sets core registers and sys_regs to reset value 76 * @vcpu: The VCPU pointer 77 * 78 * This function finds the right table above and sets the registers on 79 * the virtual CPU struct to their architectually defined reset 80 * values. 81 */ 82 int kvm_reset_vcpu(struct kvm_vcpu *vcpu) 83 { 84 const struct kvm_irq_level *cpu_vtimer_irq; 85 const struct kvm_regs *cpu_reset; 86 87 switch (vcpu->arch.target) { 88 default: 89 if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) { 90 if (!cpu_has_32bit_el1()) 91 return -EINVAL; 92 cpu_reset = &default_regs_reset32; 93 } else { 94 cpu_reset = &default_regs_reset; 95 } 96 97 cpu_vtimer_irq = &default_vtimer_irq; 98 break; 99 } 100 101 /* Reset core registers */ 102 memcpy(vcpu_gp_regs(vcpu), cpu_reset, sizeof(*cpu_reset)); 103 104 /* Reset system registers */ 105 kvm_reset_sys_regs(vcpu); 106 107 /* Reset timer */ 108 kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq); 109 110 return 0; 111 } 112