1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2012 - Virtual Open Systems and Columbia University 4 * Author: Christoffer Dall <c.dall@virtualopensystems.com> 5 */ 6 #include <linux/compiler.h> 7 #include <linux/errno.h> 8 #include <linux/sched.h> 9 #include <linux/kvm_host.h> 10 #include <linux/kvm.h> 11 12 #include <asm/unified.h> 13 #include <asm/ptrace.h> 14 #include <asm/cputype.h> 15 #include <asm/kvm_arm.h> 16 #include <asm/kvm_coproc.h> 17 #include <asm/kvm_emulate.h> 18 19 #include <kvm/arm_arch_timer.h> 20 21 /****************************************************************************** 22 * Cortex-A15 and Cortex-A7 Reset Values 23 */ 24 25 static struct kvm_regs cortexa_regs_reset = { 26 .usr_regs.ARM_cpsr = SVC_MODE | PSR_A_BIT | PSR_I_BIT | PSR_F_BIT, 27 }; 28 29 30 /******************************************************************************* 31 * Exported reset function 32 */ 33 34 /** 35 * kvm_reset_vcpu - sets core registers and cp15 registers to reset value 36 * @vcpu: The VCPU pointer 37 * 38 * This function finds the right table above and sets the registers on the 39 * virtual CPU struct to their architecturally defined reset values. 40 */ kvm_reset_vcpu(struct kvm_vcpu * vcpu)41int kvm_reset_vcpu(struct kvm_vcpu *vcpu) 42 { 43 struct kvm_regs *reset_regs; 44 45 switch (vcpu->arch.target) { 46 case KVM_ARM_TARGET_CORTEX_A7: 47 case KVM_ARM_TARGET_CORTEX_A15: 48 reset_regs = &cortexa_regs_reset; 49 vcpu->arch.midr = read_cpuid_id(); 50 break; 51 default: 52 return -ENODEV; 53 } 54 55 /* Reset core registers */ 56 memcpy(&vcpu->arch.ctxt.gp_regs, reset_regs, sizeof(vcpu->arch.ctxt.gp_regs)); 57 58 /* Reset CP15 registers */ 59 kvm_reset_coprocs(vcpu); 60 61 /* 62 * Additional reset state handling that PSCI may have imposed on us. 63 * Must be done after all the sys_reg reset. 64 */ 65 if (READ_ONCE(vcpu->arch.reset_state.reset)) { 66 unsigned long target_pc = vcpu->arch.reset_state.pc; 67 68 /* Gracefully handle Thumb2 entry point */ 69 if (target_pc & 1) { 70 target_pc &= ~1UL; 71 vcpu_set_thumb(vcpu); 72 } 73 74 /* Propagate caller endianness */ 75 if (vcpu->arch.reset_state.be) 76 kvm_vcpu_set_be(vcpu); 77 78 *vcpu_pc(vcpu) = target_pc; 79 vcpu_set_reg(vcpu, 0, vcpu->arch.reset_state.r0); 80 81 vcpu->arch.reset_state.reset = false; 82 } 83 84 /* Reset arch_timer context */ 85 return kvm_timer_vcpu_reset(vcpu); 86 } 87