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_coproc.h> 33 34 /* 35 * ARMv8 Reset Values 36 */ 37 static const struct kvm_regs default_regs_reset = { 38 .regs.pstate = (PSR_MODE_EL1h | PSR_A_BIT | PSR_I_BIT | 39 PSR_F_BIT | PSR_D_BIT), 40 }; 41 42 static const struct kvm_regs default_regs_reset32 = { 43 .regs.pstate = (COMPAT_PSR_MODE_SVC | COMPAT_PSR_A_BIT | 44 COMPAT_PSR_I_BIT | COMPAT_PSR_F_BIT), 45 }; 46 47 static const struct kvm_irq_level default_vtimer_irq = { 48 .irq = 27, 49 .level = 1, 50 }; 51 52 static bool cpu_has_32bit_el1(void) 53 { 54 u64 pfr0; 55 56 pfr0 = read_system_reg(SYS_ID_AA64PFR0_EL1); 57 return !!(pfr0 & 0x20); 58 } 59 60 /** 61 * kvm_arch_dev_ioctl_check_extension 62 * 63 * We currently assume that the number of HW registers is uniform 64 * across all CPUs (see cpuinfo_sanity_check). 65 */ 66 int kvm_arch_dev_ioctl_check_extension(long ext) 67 { 68 int r; 69 70 switch (ext) { 71 case KVM_CAP_ARM_EL1_32BIT: 72 r = cpu_has_32bit_el1(); 73 break; 74 case KVM_CAP_GUEST_DEBUG_HW_BPS: 75 r = get_num_brps(); 76 break; 77 case KVM_CAP_GUEST_DEBUG_HW_WPS: 78 r = get_num_wrps(); 79 break; 80 case KVM_CAP_SET_GUEST_DEBUG: 81 r = 1; 82 break; 83 default: 84 r = 0; 85 } 86 87 return r; 88 } 89 90 /** 91 * kvm_reset_vcpu - sets core registers and sys_regs to reset value 92 * @vcpu: The VCPU pointer 93 * 94 * This function finds the right table above and sets the registers on 95 * the virtual CPU struct to their architectually defined reset 96 * values. 97 */ 98 int kvm_reset_vcpu(struct kvm_vcpu *vcpu) 99 { 100 const struct kvm_irq_level *cpu_vtimer_irq; 101 const struct kvm_regs *cpu_reset; 102 103 switch (vcpu->arch.target) { 104 default: 105 if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) { 106 if (!cpu_has_32bit_el1()) 107 return -EINVAL; 108 cpu_reset = &default_regs_reset32; 109 } else { 110 cpu_reset = &default_regs_reset; 111 } 112 113 cpu_vtimer_irq = &default_vtimer_irq; 114 break; 115 } 116 117 /* Reset core registers */ 118 memcpy(vcpu_gp_regs(vcpu), cpu_reset, sizeof(*cpu_reset)); 119 120 /* Reset system registers */ 121 kvm_reset_sys_regs(vcpu); 122 123 /* Reset timer */ 124 return kvm_timer_vcpu_reset(vcpu, cpu_vtimer_irq); 125 } 126