2 * Copyright (C) 2012,2013 - ARM Ltd
3 * Author: Marc Zyngier <marc.zyngier@arm.com>
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>
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.
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.
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/>.
22 #include <linux/errno.h>
23 #include <linux/kvm_host.h>
24 #include <linux/kvm.h>
25 #include <linux/hw_breakpoint.h>
27 #include <kvm/arm_arch_timer.h>
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>
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),
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),
49 static bool cpu_has_32bit_el1(void)
53 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
54 return !!(pfr0 & 0x20);
58 * kvm_arch_dev_ioctl_check_extension
60 * We currently assume that the number of HW registers is uniform
61 * across all CPUs (see cpuinfo_sanity_check).
63 int kvm_arch_dev_ioctl_check_extension(struct kvm *kvm, long ext)
68 case KVM_CAP_ARM_EL1_32BIT:
69 r = cpu_has_32bit_el1();
71 case KVM_CAP_GUEST_DEBUG_HW_BPS:
74 case KVM_CAP_GUEST_DEBUG_HW_WPS:
77 case KVM_CAP_ARM_PMU_V3:
78 r = kvm_arm_support_pmu_v3();
80 case KVM_CAP_SET_GUEST_DEBUG:
81 case KVM_CAP_VCPU_ATTRIBUTES:
92 * kvm_reset_vcpu - sets core registers and sys_regs to reset value
93 * @vcpu: The VCPU pointer
95 * This function finds the right table above and sets the registers on
96 * the virtual CPU struct to their architecturally defined reset
99 * Note: This function can be called from two paths: The KVM_ARM_VCPU_INIT
100 * ioctl or as part of handling a request issued by another VCPU in the PSCI
101 * handling code. In the first case, the VCPU will not be loaded, and in the
102 * second case the VCPU will be loaded. Because this function operates purely
103 * on the memory-backed valus of system registers, we want to do a full put if
104 * we were loaded (handling a request) and load the values back at the end of
105 * the function. Otherwise we leave the state alone. In both cases, we
106 * disable preemption around the vcpu reset as we would otherwise race with
107 * preempt notifiers which also call put/load.
109 int kvm_reset_vcpu(struct kvm_vcpu *vcpu)
111 const struct kvm_regs *cpu_reset;
116 loaded = (vcpu->cpu != -1);
118 kvm_arch_vcpu_put(vcpu);
120 switch (vcpu->arch.target) {
122 if (test_bit(KVM_ARM_VCPU_EL1_32BIT, vcpu->arch.features)) {
123 if (!cpu_has_32bit_el1())
125 cpu_reset = &default_regs_reset32;
127 cpu_reset = &default_regs_reset;
133 /* Reset core registers */
134 memcpy(vcpu_gp_regs(vcpu), cpu_reset, sizeof(*cpu_reset));
136 /* Reset system registers */
137 kvm_reset_sys_regs(vcpu);
140 kvm_pmu_vcpu_reset(vcpu);
142 /* Default workaround setup is enabled (if supported) */
143 if (kvm_arm_have_ssbd() == KVM_SSBD_KERNEL)
144 vcpu->arch.workaround_flags |= VCPU_WORKAROUND_2_FLAG;
147 ret = kvm_timer_vcpu_reset(vcpu);
150 kvm_arch_vcpu_load(vcpu, smp_processor_id());