/*
 * QEMU Hypervisor.framework support for Apple Silicon

 * Copyright 2020 Alexander Graf <agraf@csgraf.de>
 * Copyright 2020 Google LLC
 *
 * This work is licensed under the terms of the GNU GPL, version 2 or later.
 * See the COPYING file in the top-level directory.
 *
 */

#include "qemu/osdep.h"
#include "qemu-common.h"
#include "qemu/error-report.h"

#include "sysemu/runstate.h"
#include "sysemu/hvf.h"
#include "sysemu/hvf_int.h"
#include "sysemu/hw_accel.h"
#include "hvf_arm.h"

#include <mach/mach_time.h>

#include "exec/address-spaces.h"
#include "hw/irq.h"
#include "qemu/main-loop.h"
#include "sysemu/cpus.h"
#include "arm-powerctl.h"
#include "target/arm/cpu.h"
#include "target/arm/internals.h"
#include "trace/trace-target_arm_hvf.h"
#include "migration/vmstate.h"

#define HVF_SYSREG(crn, crm, op0, op1, op2) \
        ENCODE_AA64_CP_REG(CP_REG_ARM64_SYSREG_CP, crn, crm, op0, op1, op2)
#define PL1_WRITE_MASK 0x4

#define SYSREG_OP0_SHIFT      20
#define SYSREG_OP0_MASK       0x3
#define SYSREG_OP0(sysreg)    ((sysreg >> SYSREG_OP0_SHIFT) & SYSREG_OP0_MASK)
#define SYSREG_OP1_SHIFT      14
#define SYSREG_OP1_MASK       0x7
#define SYSREG_OP1(sysreg)    ((sysreg >> SYSREG_OP1_SHIFT) & SYSREG_OP1_MASK)
#define SYSREG_CRN_SHIFT      10
#define SYSREG_CRN_MASK       0xf
#define SYSREG_CRN(sysreg)    ((sysreg >> SYSREG_CRN_SHIFT) & SYSREG_CRN_MASK)
#define SYSREG_CRM_SHIFT      1
#define SYSREG_CRM_MASK       0xf
#define SYSREG_CRM(sysreg)    ((sysreg >> SYSREG_CRM_SHIFT) & SYSREG_CRM_MASK)
#define SYSREG_OP2_SHIFT      17
#define SYSREG_OP2_MASK       0x7
#define SYSREG_OP2(sysreg)    ((sysreg >> SYSREG_OP2_SHIFT) & SYSREG_OP2_MASK)

#define SYSREG(op0, op1, crn, crm, op2) \
    ((op0 << SYSREG_OP0_SHIFT) | \
     (op1 << SYSREG_OP1_SHIFT) | \
     (crn << SYSREG_CRN_SHIFT) | \
     (crm << SYSREG_CRM_SHIFT) | \
     (op2 << SYSREG_OP2_SHIFT))
#define SYSREG_MASK \
    SYSREG(SYSREG_OP0_MASK, \
           SYSREG_OP1_MASK, \
           SYSREG_CRN_MASK, \
           SYSREG_CRM_MASK, \
           SYSREG_OP2_MASK)
#define SYSREG_OSLAR_EL1      SYSREG(2, 0, 1, 0, 4)
#define SYSREG_OSLSR_EL1      SYSREG(2, 0, 1, 1, 4)
#define SYSREG_OSDLR_EL1      SYSREG(2, 0, 1, 3, 4)
#define SYSREG_CNTPCT_EL0     SYSREG(3, 3, 14, 0, 1)
#define SYSREG_PMCR_EL0       SYSREG(3, 3, 9, 12, 0)
#define SYSREG_PMUSERENR_EL0  SYSREG(3, 3, 9, 14, 0)
#define SYSREG_PMCNTENSET_EL0 SYSREG(3, 3, 9, 12, 1)
#define SYSREG_PMCNTENCLR_EL0 SYSREG(3, 3, 9, 12, 2)
#define SYSREG_PMINTENCLR_EL1 SYSREG(3, 0, 9, 14, 2)
#define SYSREG_PMOVSCLR_EL0   SYSREG(3, 3, 9, 12, 3)
#define SYSREG_PMSWINC_EL0    SYSREG(3, 3, 9, 12, 4)
#define SYSREG_PMSELR_EL0     SYSREG(3, 3, 9, 12, 5)
#define SYSREG_PMCEID0_EL0    SYSREG(3, 3, 9, 12, 6)
#define SYSREG_PMCEID1_EL0    SYSREG(3, 3, 9, 12, 7)
#define SYSREG_PMCCNTR_EL0    SYSREG(3, 3, 9, 13, 0)
#define SYSREG_PMCCFILTR_EL0  SYSREG(3, 3, 14, 15, 7)

#define WFX_IS_WFE (1 << 0)

#define TMR_CTL_ENABLE  (1 << 0)
#define TMR_CTL_IMASK   (1 << 1)
#define TMR_CTL_ISTATUS (1 << 2)

static void hvf_wfi(CPUState *cpu);

typedef struct HVFVTimer {
    /* Vtimer value during migration and paused state */
    uint64_t vtimer_val;
} HVFVTimer;

static HVFVTimer vtimer;

typedef struct ARMHostCPUFeatures {
    ARMISARegisters isar;
    uint64_t features;
    uint64_t midr;
    uint32_t reset_sctlr;
    const char *dtb_compatible;
} ARMHostCPUFeatures;

static ARMHostCPUFeatures arm_host_cpu_features;

struct hvf_reg_match {
    int reg;
    uint64_t offset;
};

static const struct hvf_reg_match hvf_reg_match[] = {
    { HV_REG_X0,   offsetof(CPUARMState, xregs[0]) },
    { HV_REG_X1,   offsetof(CPUARMState, xregs[1]) },
    { HV_REG_X2,   offsetof(CPUARMState, xregs[2]) },
    { HV_REG_X3,   offsetof(CPUARMState, xregs[3]) },
    { HV_REG_X4,   offsetof(CPUARMState, xregs[4]) },
    { HV_REG_X5,   offsetof(CPUARMState, xregs[5]) },
    { HV_REG_X6,   offsetof(CPUARMState, xregs[6]) },
    { HV_REG_X7,   offsetof(CPUARMState, xregs[7]) },
    { HV_REG_X8,   offsetof(CPUARMState, xregs[8]) },
    { HV_REG_X9,   offsetof(CPUARMState, xregs[9]) },
    { HV_REG_X10,  offsetof(CPUARMState, xregs[10]) },
    { HV_REG_X11,  offsetof(CPUARMState, xregs[11]) },
    { HV_REG_X12,  offsetof(CPUARMState, xregs[12]) },
    { HV_REG_X13,  offsetof(CPUARMState, xregs[13]) },
    { HV_REG_X14,  offsetof(CPUARMState, xregs[14]) },
    { HV_REG_X15,  offsetof(CPUARMState, xregs[15]) },
    { HV_REG_X16,  offsetof(CPUARMState, xregs[16]) },
    { HV_REG_X17,  offsetof(CPUARMState, xregs[17]) },
    { HV_REG_X18,  offsetof(CPUARMState, xregs[18]) },
    { HV_REG_X19,  offsetof(CPUARMState, xregs[19]) },
    { HV_REG_X20,  offsetof(CPUARMState, xregs[20]) },
    { HV_REG_X21,  offsetof(CPUARMState, xregs[21]) },
    { HV_REG_X22,  offsetof(CPUARMState, xregs[22]) },
    { HV_REG_X23,  offsetof(CPUARMState, xregs[23]) },
    { HV_REG_X24,  offsetof(CPUARMState, xregs[24]) },
    { HV_REG_X25,  offsetof(CPUARMState, xregs[25]) },
    { HV_REG_X26,  offsetof(CPUARMState, xregs[26]) },
    { HV_REG_X27,  offsetof(CPUARMState, xregs[27]) },
    { HV_REG_X28,  offsetof(CPUARMState, xregs[28]) },
    { HV_REG_X29,  offsetof(CPUARMState, xregs[29]) },
    { HV_REG_X30,  offsetof(CPUARMState, xregs[30]) },
    { HV_REG_PC,   offsetof(CPUARMState, pc) },
};

static const struct hvf_reg_match hvf_fpreg_match[] = {
    { HV_SIMD_FP_REG_Q0,  offsetof(CPUARMState, vfp.zregs[0]) },
    { HV_SIMD_FP_REG_Q1,  offsetof(CPUARMState, vfp.zregs[1]) },
    { HV_SIMD_FP_REG_Q2,  offsetof(CPUARMState, vfp.zregs[2]) },
    { HV_SIMD_FP_REG_Q3,  offsetof(CPUARMState, vfp.zregs[3]) },
    { HV_SIMD_FP_REG_Q4,  offsetof(CPUARMState, vfp.zregs[4]) },
    { HV_SIMD_FP_REG_Q5,  offsetof(CPUARMState, vfp.zregs[5]) },
    { HV_SIMD_FP_REG_Q6,  offsetof(CPUARMState, vfp.zregs[6]) },
    { HV_SIMD_FP_REG_Q7,  offsetof(CPUARMState, vfp.zregs[7]) },
    { HV_SIMD_FP_REG_Q8,  offsetof(CPUARMState, vfp.zregs[8]) },
    { HV_SIMD_FP_REG_Q9,  offsetof(CPUARMState, vfp.zregs[9]) },
    { HV_SIMD_FP_REG_Q10, offsetof(CPUARMState, vfp.zregs[10]) },
    { HV_SIMD_FP_REG_Q11, offsetof(CPUARMState, vfp.zregs[11]) },
    { HV_SIMD_FP_REG_Q12, offsetof(CPUARMState, vfp.zregs[12]) },
    { HV_SIMD_FP_REG_Q13, offsetof(CPUARMState, vfp.zregs[13]) },
    { HV_SIMD_FP_REG_Q14, offsetof(CPUARMState, vfp.zregs[14]) },
    { HV_SIMD_FP_REG_Q15, offsetof(CPUARMState, vfp.zregs[15]) },
    { HV_SIMD_FP_REG_Q16, offsetof(CPUARMState, vfp.zregs[16]) },
    { HV_SIMD_FP_REG_Q17, offsetof(CPUARMState, vfp.zregs[17]) },
    { HV_SIMD_FP_REG_Q18, offsetof(CPUARMState, vfp.zregs[18]) },
    { HV_SIMD_FP_REG_Q19, offsetof(CPUARMState, vfp.zregs[19]) },
    { HV_SIMD_FP_REG_Q20, offsetof(CPUARMState, vfp.zregs[20]) },
    { HV_SIMD_FP_REG_Q21, offsetof(CPUARMState, vfp.zregs[21]) },
    { HV_SIMD_FP_REG_Q22, offsetof(CPUARMState, vfp.zregs[22]) },
    { HV_SIMD_FP_REG_Q23, offsetof(CPUARMState, vfp.zregs[23]) },
    { HV_SIMD_FP_REG_Q24, offsetof(CPUARMState, vfp.zregs[24]) },
    { HV_SIMD_FP_REG_Q25, offsetof(CPUARMState, vfp.zregs[25]) },
    { HV_SIMD_FP_REG_Q26, offsetof(CPUARMState, vfp.zregs[26]) },
    { HV_SIMD_FP_REG_Q27, offsetof(CPUARMState, vfp.zregs[27]) },
    { HV_SIMD_FP_REG_Q28, offsetof(CPUARMState, vfp.zregs[28]) },
    { HV_SIMD_FP_REG_Q29, offsetof(CPUARMState, vfp.zregs[29]) },
    { HV_SIMD_FP_REG_Q30, offsetof(CPUARMState, vfp.zregs[30]) },
    { HV_SIMD_FP_REG_Q31, offsetof(CPUARMState, vfp.zregs[31]) },
};

struct hvf_sreg_match {
    int reg;
    uint32_t key;
    uint32_t cp_idx;
};

static struct hvf_sreg_match hvf_sreg_match[] = {
    { HV_SYS_REG_DBGBVR0_EL1, HVF_SYSREG(0, 0, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR0_EL1, HVF_SYSREG(0, 0, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR0_EL1, HVF_SYSREG(0, 0, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR0_EL1, HVF_SYSREG(0, 0, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR1_EL1, HVF_SYSREG(0, 1, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR1_EL1, HVF_SYSREG(0, 1, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR1_EL1, HVF_SYSREG(0, 1, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR1_EL1, HVF_SYSREG(0, 1, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR2_EL1, HVF_SYSREG(0, 2, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR2_EL1, HVF_SYSREG(0, 2, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR2_EL1, HVF_SYSREG(0, 2, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR2_EL1, HVF_SYSREG(0, 2, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR3_EL1, HVF_SYSREG(0, 3, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR3_EL1, HVF_SYSREG(0, 3, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR3_EL1, HVF_SYSREG(0, 3, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR3_EL1, HVF_SYSREG(0, 3, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR4_EL1, HVF_SYSREG(0, 4, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR4_EL1, HVF_SYSREG(0, 4, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR4_EL1, HVF_SYSREG(0, 4, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR4_EL1, HVF_SYSREG(0, 4, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR5_EL1, HVF_SYSREG(0, 5, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR5_EL1, HVF_SYSREG(0, 5, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR5_EL1, HVF_SYSREG(0, 5, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR5_EL1, HVF_SYSREG(0, 5, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR6_EL1, HVF_SYSREG(0, 6, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR6_EL1, HVF_SYSREG(0, 6, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR6_EL1, HVF_SYSREG(0, 6, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR6_EL1, HVF_SYSREG(0, 6, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR7_EL1, HVF_SYSREG(0, 7, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR7_EL1, HVF_SYSREG(0, 7, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR7_EL1, HVF_SYSREG(0, 7, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR7_EL1, HVF_SYSREG(0, 7, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR8_EL1, HVF_SYSREG(0, 8, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR8_EL1, HVF_SYSREG(0, 8, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR8_EL1, HVF_SYSREG(0, 8, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR8_EL1, HVF_SYSREG(0, 8, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR9_EL1, HVF_SYSREG(0, 9, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR9_EL1, HVF_SYSREG(0, 9, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR9_EL1, HVF_SYSREG(0, 9, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR9_EL1, HVF_SYSREG(0, 9, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR10_EL1, HVF_SYSREG(0, 10, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR10_EL1, HVF_SYSREG(0, 10, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR10_EL1, HVF_SYSREG(0, 10, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR10_EL1, HVF_SYSREG(0, 10, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR11_EL1, HVF_SYSREG(0, 11, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR11_EL1, HVF_SYSREG(0, 11, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR11_EL1, HVF_SYSREG(0, 11, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR11_EL1, HVF_SYSREG(0, 11, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR12_EL1, HVF_SYSREG(0, 12, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR12_EL1, HVF_SYSREG(0, 12, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR12_EL1, HVF_SYSREG(0, 12, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR12_EL1, HVF_SYSREG(0, 12, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR13_EL1, HVF_SYSREG(0, 13, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR13_EL1, HVF_SYSREG(0, 13, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR13_EL1, HVF_SYSREG(0, 13, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR13_EL1, HVF_SYSREG(0, 13, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR14_EL1, HVF_SYSREG(0, 14, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR14_EL1, HVF_SYSREG(0, 14, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR14_EL1, HVF_SYSREG(0, 14, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR14_EL1, HVF_SYSREG(0, 14, 14, 0, 7) },

    { HV_SYS_REG_DBGBVR15_EL1, HVF_SYSREG(0, 15, 14, 0, 4) },
    { HV_SYS_REG_DBGBCR15_EL1, HVF_SYSREG(0, 15, 14, 0, 5) },
    { HV_SYS_REG_DBGWVR15_EL1, HVF_SYSREG(0, 15, 14, 0, 6) },
    { HV_SYS_REG_DBGWCR15_EL1, HVF_SYSREG(0, 15, 14, 0, 7) },

#ifdef SYNC_NO_RAW_REGS
    /*
     * The registers below are manually synced on init because they are
     * marked as NO_RAW. We still list them to make number space sync easier.
     */
    { HV_SYS_REG_MDCCINT_EL1, HVF_SYSREG(0, 2, 2, 0, 0) },
    { HV_SYS_REG_MIDR_EL1, HVF_SYSREG(0, 0, 3, 0, 0) },
    { HV_SYS_REG_MPIDR_EL1, HVF_SYSREG(0, 0, 3, 0, 5) },
    { HV_SYS_REG_ID_AA64PFR0_EL1, HVF_SYSREG(0, 4, 3, 0, 0) },
#endif
    { HV_SYS_REG_ID_AA64PFR1_EL1, HVF_SYSREG(0, 4, 3, 0, 2) },
    { HV_SYS_REG_ID_AA64DFR0_EL1, HVF_SYSREG(0, 5, 3, 0, 0) },
    { HV_SYS_REG_ID_AA64DFR1_EL1, HVF_SYSREG(0, 5, 3, 0, 1) },
    { HV_SYS_REG_ID_AA64ISAR0_EL1, HVF_SYSREG(0, 6, 3, 0, 0) },
    { HV_SYS_REG_ID_AA64ISAR1_EL1, HVF_SYSREG(0, 6, 3, 0, 1) },
#ifdef SYNC_NO_MMFR0
    /* We keep the hardware MMFR0 around. HW limits are there anyway */
    { HV_SYS_REG_ID_AA64MMFR0_EL1, HVF_SYSREG(0, 7, 3, 0, 0) },
#endif
    { HV_SYS_REG_ID_AA64MMFR1_EL1, HVF_SYSREG(0, 7, 3, 0, 1) },
    { HV_SYS_REG_ID_AA64MMFR2_EL1, HVF_SYSREG(0, 7, 3, 0, 2) },

    { HV_SYS_REG_MDSCR_EL1, HVF_SYSREG(0, 2, 2, 0, 2) },
    { HV_SYS_REG_SCTLR_EL1, HVF_SYSREG(1, 0, 3, 0, 0) },
    { HV_SYS_REG_CPACR_EL1, HVF_SYSREG(1, 0, 3, 0, 2) },
    { HV_SYS_REG_TTBR0_EL1, HVF_SYSREG(2, 0, 3, 0, 0) },
    { HV_SYS_REG_TTBR1_EL1, HVF_SYSREG(2, 0, 3, 0, 1) },
    { HV_SYS_REG_TCR_EL1, HVF_SYSREG(2, 0, 3, 0, 2) },

    { HV_SYS_REG_APIAKEYLO_EL1, HVF_SYSREG(2, 1, 3, 0, 0) },
    { HV_SYS_REG_APIAKEYHI_EL1, HVF_SYSREG(2, 1, 3, 0, 1) },
    { HV_SYS_REG_APIBKEYLO_EL1, HVF_SYSREG(2, 1, 3, 0, 2) },
    { HV_SYS_REG_APIBKEYHI_EL1, HVF_SYSREG(2, 1, 3, 0, 3) },
    { HV_SYS_REG_APDAKEYLO_EL1, HVF_SYSREG(2, 2, 3, 0, 0) },
    { HV_SYS_REG_APDAKEYHI_EL1, HVF_SYSREG(2, 2, 3, 0, 1) },
    { HV_SYS_REG_APDBKEYLO_EL1, HVF_SYSREG(2, 2, 3, 0, 2) },
    { HV_SYS_REG_APDBKEYHI_EL1, HVF_SYSREG(2, 2, 3, 0, 3) },
    { HV_SYS_REG_APGAKEYLO_EL1, HVF_SYSREG(2, 3, 3, 0, 0) },
    { HV_SYS_REG_APGAKEYHI_EL1, HVF_SYSREG(2, 3, 3, 0, 1) },

    { HV_SYS_REG_SPSR_EL1, HVF_SYSREG(4, 0, 3, 0, 0) },
    { HV_SYS_REG_ELR_EL1, HVF_SYSREG(4, 0, 3, 0, 1) },
    { HV_SYS_REG_SP_EL0, HVF_SYSREG(4, 1, 3, 0, 0) },
    { HV_SYS_REG_AFSR0_EL1, HVF_SYSREG(5, 1, 3, 0, 0) },
    { HV_SYS_REG_AFSR1_EL1, HVF_SYSREG(5, 1, 3, 0, 1) },
    { HV_SYS_REG_ESR_EL1, HVF_SYSREG(5, 2, 3, 0, 0) },
    { HV_SYS_REG_FAR_EL1, HVF_SYSREG(6, 0, 3, 0, 0) },
    { HV_SYS_REG_PAR_EL1, HVF_SYSREG(7, 4, 3, 0, 0) },
    { HV_SYS_REG_MAIR_EL1, HVF_SYSREG(10, 2, 3, 0, 0) },
    { HV_SYS_REG_AMAIR_EL1, HVF_SYSREG(10, 3, 3, 0, 0) },
    { HV_SYS_REG_VBAR_EL1, HVF_SYSREG(12, 0, 3, 0, 0) },
    { HV_SYS_REG_CONTEXTIDR_EL1, HVF_SYSREG(13, 0, 3, 0, 1) },
    { HV_SYS_REG_TPIDR_EL1, HVF_SYSREG(13, 0, 3, 0, 4) },
    { HV_SYS_REG_CNTKCTL_EL1, HVF_SYSREG(14, 1, 3, 0, 0) },
    { HV_SYS_REG_CSSELR_EL1, HVF_SYSREG(0, 0, 3, 2, 0) },
    { HV_SYS_REG_TPIDR_EL0, HVF_SYSREG(13, 0, 3, 3, 2) },
    { HV_SYS_REG_TPIDRRO_EL0, HVF_SYSREG(13, 0, 3, 3, 3) },
    { HV_SYS_REG_CNTV_CTL_EL0, HVF_SYSREG(14, 3, 3, 3, 1) },
    { HV_SYS_REG_CNTV_CVAL_EL0, HVF_SYSREG(14, 3, 3, 3, 2) },
    { HV_SYS_REG_SP_EL1, HVF_SYSREG(4, 1, 3, 4, 0) },
};

int hvf_get_registers(CPUState *cpu)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    CPUARMState *env = &arm_cpu->env;
    hv_return_t ret;
    uint64_t val;
    hv_simd_fp_uchar16_t fpval;
    int i;

    for (i = 0; i < ARRAY_SIZE(hvf_reg_match); i++) {
        ret = hv_vcpu_get_reg(cpu->hvf->fd, hvf_reg_match[i].reg, &val);
        *(uint64_t *)((void *)env + hvf_reg_match[i].offset) = val;
        assert_hvf_ok(ret);
    }

    for (i = 0; i < ARRAY_SIZE(hvf_fpreg_match); i++) {
        ret = hv_vcpu_get_simd_fp_reg(cpu->hvf->fd, hvf_fpreg_match[i].reg,
                                      &fpval);
        memcpy((void *)env + hvf_fpreg_match[i].offset, &fpval, sizeof(fpval));
        assert_hvf_ok(ret);
    }

    val = 0;
    ret = hv_vcpu_get_reg(cpu->hvf->fd, HV_REG_FPCR, &val);
    assert_hvf_ok(ret);
    vfp_set_fpcr(env, val);

    val = 0;
    ret = hv_vcpu_get_reg(cpu->hvf->fd, HV_REG_FPSR, &val);
    assert_hvf_ok(ret);
    vfp_set_fpsr(env, val);

    ret = hv_vcpu_get_reg(cpu->hvf->fd, HV_REG_CPSR, &val);
    assert_hvf_ok(ret);
    pstate_write(env, val);

    for (i = 0; i < ARRAY_SIZE(hvf_sreg_match); i++) {
        if (hvf_sreg_match[i].cp_idx == -1) {
            continue;
        }

        ret = hv_vcpu_get_sys_reg(cpu->hvf->fd, hvf_sreg_match[i].reg, &val);
        assert_hvf_ok(ret);

        arm_cpu->cpreg_values[hvf_sreg_match[i].cp_idx] = val;
    }
    assert(write_list_to_cpustate(arm_cpu));

    aarch64_restore_sp(env, arm_current_el(env));

    return 0;
}

int hvf_put_registers(CPUState *cpu)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    CPUARMState *env = &arm_cpu->env;
    hv_return_t ret;
    uint64_t val;
    hv_simd_fp_uchar16_t fpval;
    int i;

    for (i = 0; i < ARRAY_SIZE(hvf_reg_match); i++) {
        val = *(uint64_t *)((void *)env + hvf_reg_match[i].offset);
        ret = hv_vcpu_set_reg(cpu->hvf->fd, hvf_reg_match[i].reg, val);
        assert_hvf_ok(ret);
    }

    for (i = 0; i < ARRAY_SIZE(hvf_fpreg_match); i++) {
        memcpy(&fpval, (void *)env + hvf_fpreg_match[i].offset, sizeof(fpval));
        ret = hv_vcpu_set_simd_fp_reg(cpu->hvf->fd, hvf_fpreg_match[i].reg,
                                      fpval);
        assert_hvf_ok(ret);
    }

    ret = hv_vcpu_set_reg(cpu->hvf->fd, HV_REG_FPCR, vfp_get_fpcr(env));
    assert_hvf_ok(ret);

    ret = hv_vcpu_set_reg(cpu->hvf->fd, HV_REG_FPSR, vfp_get_fpsr(env));
    assert_hvf_ok(ret);

    ret = hv_vcpu_set_reg(cpu->hvf->fd, HV_REG_CPSR, pstate_read(env));
    assert_hvf_ok(ret);

    aarch64_save_sp(env, arm_current_el(env));

    assert(write_cpustate_to_list(arm_cpu, false));
    for (i = 0; i < ARRAY_SIZE(hvf_sreg_match); i++) {
        if (hvf_sreg_match[i].cp_idx == -1) {
            continue;
        }

        val = arm_cpu->cpreg_values[hvf_sreg_match[i].cp_idx];
        ret = hv_vcpu_set_sys_reg(cpu->hvf->fd, hvf_sreg_match[i].reg, val);
        assert_hvf_ok(ret);
    }

    ret = hv_vcpu_set_vtimer_offset(cpu->hvf->fd, hvf_state->vtimer_offset);
    assert_hvf_ok(ret);

    return 0;
}

static void flush_cpu_state(CPUState *cpu)
{
    if (cpu->vcpu_dirty) {
        hvf_put_registers(cpu);
        cpu->vcpu_dirty = false;
    }
}

static void hvf_set_reg(CPUState *cpu, int rt, uint64_t val)
{
    hv_return_t r;

    flush_cpu_state(cpu);

    if (rt < 31) {
        r = hv_vcpu_set_reg(cpu->hvf->fd, HV_REG_X0 + rt, val);
        assert_hvf_ok(r);
    }
}

static uint64_t hvf_get_reg(CPUState *cpu, int rt)
{
    uint64_t val = 0;
    hv_return_t r;

    flush_cpu_state(cpu);

    if (rt < 31) {
        r = hv_vcpu_get_reg(cpu->hvf->fd, HV_REG_X0 + rt, &val);
        assert_hvf_ok(r);
    }

    return val;
}

static bool hvf_arm_get_host_cpu_features(ARMHostCPUFeatures *ahcf)
{
    ARMISARegisters host_isar = {};
    const struct isar_regs {
        int reg;
        uint64_t *val;
    } regs[] = {
        { HV_SYS_REG_ID_AA64PFR0_EL1, &host_isar.id_aa64pfr0 },
        { HV_SYS_REG_ID_AA64PFR1_EL1, &host_isar.id_aa64pfr1 },
        { HV_SYS_REG_ID_AA64DFR0_EL1, &host_isar.id_aa64dfr0 },
        { HV_SYS_REG_ID_AA64DFR1_EL1, &host_isar.id_aa64dfr1 },
        { HV_SYS_REG_ID_AA64ISAR0_EL1, &host_isar.id_aa64isar0 },
        { HV_SYS_REG_ID_AA64ISAR1_EL1, &host_isar.id_aa64isar1 },
        { HV_SYS_REG_ID_AA64MMFR0_EL1, &host_isar.id_aa64mmfr0 },
        { HV_SYS_REG_ID_AA64MMFR1_EL1, &host_isar.id_aa64mmfr1 },
        { HV_SYS_REG_ID_AA64MMFR2_EL1, &host_isar.id_aa64mmfr2 },
    };
    hv_vcpu_t fd;
    hv_return_t r = HV_SUCCESS;
    hv_vcpu_exit_t *exit;
    int i;

    ahcf->dtb_compatible = "arm,arm-v8";
    ahcf->features = (1ULL << ARM_FEATURE_V8) |
                     (1ULL << ARM_FEATURE_NEON) |
                     (1ULL << ARM_FEATURE_AARCH64) |
                     (1ULL << ARM_FEATURE_PMU) |
                     (1ULL << ARM_FEATURE_GENERIC_TIMER);

    /* We set up a small vcpu to extract host registers */

    if (hv_vcpu_create(&fd, &exit, NULL) != HV_SUCCESS) {
        return false;
    }

    for (i = 0; i < ARRAY_SIZE(regs); i++) {
        r |= hv_vcpu_get_sys_reg(fd, regs[i].reg, regs[i].val);
    }
    r |= hv_vcpu_get_sys_reg(fd, HV_SYS_REG_MIDR_EL1, &ahcf->midr);
    r |= hv_vcpu_destroy(fd);

    ahcf->isar = host_isar;

    /*
     * A scratch vCPU returns SCTLR 0, so let's fill our default with the M1
     * boot SCTLR from https://github.com/AsahiLinux/m1n1/issues/97
     */
    ahcf->reset_sctlr = 0x30100180;
    /*
     * SPAN is disabled by default when SCTLR.SPAN=1. To improve compatibility,
     * let's disable it on boot and then allow guest software to turn it on by
     * setting it to 0.
     */
    ahcf->reset_sctlr |= 0x00800000;

    /* Make sure we don't advertise AArch32 support for EL0/EL1 */
    if ((host_isar.id_aa64pfr0 & 0xff) != 0x11) {
        return false;
    }

    return r == HV_SUCCESS;
}

void hvf_arm_set_cpu_features_from_host(ARMCPU *cpu)
{
    if (!arm_host_cpu_features.dtb_compatible) {
        if (!hvf_enabled() ||
            !hvf_arm_get_host_cpu_features(&arm_host_cpu_features)) {
            /*
             * We can't report this error yet, so flag that we need to
             * in arm_cpu_realizefn().
             */
            cpu->host_cpu_probe_failed = true;
            return;
        }
    }

    cpu->dtb_compatible = arm_host_cpu_features.dtb_compatible;
    cpu->isar = arm_host_cpu_features.isar;
    cpu->env.features = arm_host_cpu_features.features;
    cpu->midr = arm_host_cpu_features.midr;
    cpu->reset_sctlr = arm_host_cpu_features.reset_sctlr;
}

void hvf_arch_vcpu_destroy(CPUState *cpu)
{
}

int hvf_arch_init_vcpu(CPUState *cpu)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    CPUARMState *env = &arm_cpu->env;
    uint32_t sregs_match_len = ARRAY_SIZE(hvf_sreg_match);
    uint32_t sregs_cnt = 0;
    uint64_t pfr;
    hv_return_t ret;
    int i;

    env->aarch64 = 1;
    asm volatile("mrs %0, cntfrq_el0" : "=r"(arm_cpu->gt_cntfrq_hz));

    /* Allocate enough space for our sysreg sync */
    arm_cpu->cpreg_indexes = g_renew(uint64_t, arm_cpu->cpreg_indexes,
                                     sregs_match_len);
    arm_cpu->cpreg_values = g_renew(uint64_t, arm_cpu->cpreg_values,
                                    sregs_match_len);
    arm_cpu->cpreg_vmstate_indexes = g_renew(uint64_t,
                                             arm_cpu->cpreg_vmstate_indexes,
                                             sregs_match_len);
    arm_cpu->cpreg_vmstate_values = g_renew(uint64_t,
                                            arm_cpu->cpreg_vmstate_values,
                                            sregs_match_len);

    memset(arm_cpu->cpreg_values, 0, sregs_match_len * sizeof(uint64_t));

    /* Populate cp list for all known sysregs */
    for (i = 0; i < sregs_match_len; i++) {
        const ARMCPRegInfo *ri;
        uint32_t key = hvf_sreg_match[i].key;

        ri = get_arm_cp_reginfo(arm_cpu->cp_regs, key);
        if (ri) {
            assert(!(ri->type & ARM_CP_NO_RAW));
            hvf_sreg_match[i].cp_idx = sregs_cnt;
            arm_cpu->cpreg_indexes[sregs_cnt++] = cpreg_to_kvm_id(key);
        } else {
            hvf_sreg_match[i].cp_idx = -1;
        }
    }
    arm_cpu->cpreg_array_len = sregs_cnt;
    arm_cpu->cpreg_vmstate_array_len = sregs_cnt;

    assert(write_cpustate_to_list(arm_cpu, false));

    /* Set CP_NO_RAW system registers on init */
    ret = hv_vcpu_set_sys_reg(cpu->hvf->fd, HV_SYS_REG_MIDR_EL1,
                              arm_cpu->midr);
    assert_hvf_ok(ret);

    ret = hv_vcpu_set_sys_reg(cpu->hvf->fd, HV_SYS_REG_MPIDR_EL1,
                              arm_cpu->mp_affinity);
    assert_hvf_ok(ret);

    ret = hv_vcpu_get_sys_reg(cpu->hvf->fd, HV_SYS_REG_ID_AA64PFR0_EL1, &pfr);
    assert_hvf_ok(ret);
    pfr |= env->gicv3state ? (1 << 24) : 0;
    ret = hv_vcpu_set_sys_reg(cpu->hvf->fd, HV_SYS_REG_ID_AA64PFR0_EL1, pfr);
    assert_hvf_ok(ret);

    /* We're limited to underlying hardware caps, override internal versions */
    ret = hv_vcpu_get_sys_reg(cpu->hvf->fd, HV_SYS_REG_ID_AA64MMFR0_EL1,
                              &arm_cpu->isar.id_aa64mmfr0);
    assert_hvf_ok(ret);

    return 0;
}

void hvf_kick_vcpu_thread(CPUState *cpu)
{
    cpus_kick_thread(cpu);
    hv_vcpus_exit(&cpu->hvf->fd, 1);
}

static void hvf_raise_exception(CPUState *cpu, uint32_t excp,
                                uint32_t syndrome)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    CPUARMState *env = &arm_cpu->env;

    cpu->exception_index = excp;
    env->exception.target_el = 1;
    env->exception.syndrome = syndrome;

    arm_cpu_do_interrupt(cpu);
}

static void hvf_psci_cpu_off(ARMCPU *arm_cpu)
{
    int32_t ret = arm_set_cpu_off(arm_cpu->mp_affinity);
    assert(ret == QEMU_ARM_POWERCTL_RET_SUCCESS);
}

/*
 * Handle a PSCI call.
 *
 * Returns 0 on success
 *         -1 when the PSCI call is unknown,
 */
static bool hvf_handle_psci_call(CPUState *cpu)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    CPUARMState *env = &arm_cpu->env;
    uint64_t param[4] = {
        env->xregs[0],
        env->xregs[1],
        env->xregs[2],
        env->xregs[3]
    };
    uint64_t context_id, mpidr;
    bool target_aarch64 = true;
    CPUState *target_cpu_state;
    ARMCPU *target_cpu;
    target_ulong entry;
    int target_el = 1;
    int32_t ret = 0;

    trace_hvf_psci_call(param[0], param[1], param[2], param[3],
                        arm_cpu->mp_affinity);

    switch (param[0]) {
    case QEMU_PSCI_0_2_FN_PSCI_VERSION:
        ret = QEMU_PSCI_VERSION_1_1;
        break;
    case QEMU_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
        ret = QEMU_PSCI_0_2_RET_TOS_MIGRATION_NOT_REQUIRED; /* No trusted OS */
        break;
    case QEMU_PSCI_0_2_FN_AFFINITY_INFO:
    case QEMU_PSCI_0_2_FN64_AFFINITY_INFO:
        mpidr = param[1];

        switch (param[2]) {
        case 0:
            target_cpu_state = arm_get_cpu_by_id(mpidr);
            if (!target_cpu_state) {
                ret = QEMU_PSCI_RET_INVALID_PARAMS;
                break;
            }
            target_cpu = ARM_CPU(target_cpu_state);

            ret = target_cpu->power_state;
            break;
        default:
            /* Everything above affinity level 0 is always on. */
            ret = 0;
        }
        break;
    case QEMU_PSCI_0_2_FN_SYSTEM_RESET:
        qemu_system_reset_request(SHUTDOWN_CAUSE_GUEST_RESET);
        /*
         * QEMU reset and shutdown are async requests, but PSCI
         * mandates that we never return from the reset/shutdown
         * call, so power the CPU off now so it doesn't execute
         * anything further.
         */
        hvf_psci_cpu_off(arm_cpu);
        break;
    case QEMU_PSCI_0_2_FN_SYSTEM_OFF:
        qemu_system_shutdown_request(SHUTDOWN_CAUSE_GUEST_SHUTDOWN);
        hvf_psci_cpu_off(arm_cpu);
        break;
    case QEMU_PSCI_0_1_FN_CPU_ON:
    case QEMU_PSCI_0_2_FN_CPU_ON:
    case QEMU_PSCI_0_2_FN64_CPU_ON:
        mpidr = param[1];
        entry = param[2];
        context_id = param[3];
        ret = arm_set_cpu_on(mpidr, entry, context_id,
                             target_el, target_aarch64);
        break;
    case QEMU_PSCI_0_1_FN_CPU_OFF:
    case QEMU_PSCI_0_2_FN_CPU_OFF:
        hvf_psci_cpu_off(arm_cpu);
        break;
    case QEMU_PSCI_0_1_FN_CPU_SUSPEND:
    case QEMU_PSCI_0_2_FN_CPU_SUSPEND:
    case QEMU_PSCI_0_2_FN64_CPU_SUSPEND:
        /* Affinity levels are not supported in QEMU */
        if (param[1] & 0xfffe0000) {
            ret = QEMU_PSCI_RET_INVALID_PARAMS;
            break;
        }
        /* Powerdown is not supported, we always go into WFI */
        env->xregs[0] = 0;
        hvf_wfi(cpu);
        break;
    case QEMU_PSCI_0_1_FN_MIGRATE:
    case QEMU_PSCI_0_2_FN_MIGRATE:
        ret = QEMU_PSCI_RET_NOT_SUPPORTED;
        break;
    case QEMU_PSCI_1_0_FN_PSCI_FEATURES:
        switch (param[1]) {
        case QEMU_PSCI_0_2_FN_PSCI_VERSION:
        case QEMU_PSCI_0_2_FN_MIGRATE_INFO_TYPE:
        case QEMU_PSCI_0_2_FN_AFFINITY_INFO:
        case QEMU_PSCI_0_2_FN64_AFFINITY_INFO:
        case QEMU_PSCI_0_2_FN_SYSTEM_RESET:
        case QEMU_PSCI_0_2_FN_SYSTEM_OFF:
        case QEMU_PSCI_0_1_FN_CPU_ON:
        case QEMU_PSCI_0_2_FN_CPU_ON:
        case QEMU_PSCI_0_2_FN64_CPU_ON:
        case QEMU_PSCI_0_1_FN_CPU_OFF:
        case QEMU_PSCI_0_2_FN_CPU_OFF:
        case QEMU_PSCI_0_1_FN_CPU_SUSPEND:
        case QEMU_PSCI_0_2_FN_CPU_SUSPEND:
        case QEMU_PSCI_0_2_FN64_CPU_SUSPEND:
        case QEMU_PSCI_1_0_FN_PSCI_FEATURES:
            ret = 0;
            break;
        case QEMU_PSCI_0_1_FN_MIGRATE:
        case QEMU_PSCI_0_2_FN_MIGRATE:
        default:
            ret = QEMU_PSCI_RET_NOT_SUPPORTED;
        }
        break;
    default:
        return false;
    }

    env->xregs[0] = ret;
    return true;
}

static bool is_id_sysreg(uint32_t reg)
{
    return SYSREG_OP0(reg) == 3 &&
           SYSREG_OP1(reg) == 0 &&
           SYSREG_CRN(reg) == 0 &&
           SYSREG_CRM(reg) >= 1 &&
           SYSREG_CRM(reg) < 8;
}

static int hvf_sysreg_read(CPUState *cpu, uint32_t reg, uint32_t rt)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    CPUARMState *env = &arm_cpu->env;
    uint64_t val = 0;

    switch (reg) {
    case SYSREG_CNTPCT_EL0:
        val = qemu_clock_get_ns(QEMU_CLOCK_VIRTUAL) /
              gt_cntfrq_period_ns(arm_cpu);
        break;
    case SYSREG_PMCR_EL0:
        val = env->cp15.c9_pmcr;
        break;
    case SYSREG_PMCCNTR_EL0:
        pmu_op_start(env);
        val = env->cp15.c15_ccnt;
        pmu_op_finish(env);
        break;
    case SYSREG_PMCNTENCLR_EL0:
        val = env->cp15.c9_pmcnten;
        break;
    case SYSREG_PMOVSCLR_EL0:
        val = env->cp15.c9_pmovsr;
        break;
    case SYSREG_PMSELR_EL0:
        val = env->cp15.c9_pmselr;
        break;
    case SYSREG_PMINTENCLR_EL1:
        val = env->cp15.c9_pminten;
        break;
    case SYSREG_PMCCFILTR_EL0:
        val = env->cp15.pmccfiltr_el0;
        break;
    case SYSREG_PMCNTENSET_EL0:
        val = env->cp15.c9_pmcnten;
        break;
    case SYSREG_PMUSERENR_EL0:
        val = env->cp15.c9_pmuserenr;
        break;
    case SYSREG_PMCEID0_EL0:
    case SYSREG_PMCEID1_EL0:
        /* We can't really count anything yet, declare all events invalid */
        val = 0;
        break;
    case SYSREG_OSLSR_EL1:
        val = env->cp15.oslsr_el1;
        break;
    case SYSREG_OSDLR_EL1:
        /* Dummy register */
        break;
    default:
        if (is_id_sysreg(reg)) {
            /* ID system registers read as RES0 */
            val = 0;
            break;
        }
        cpu_synchronize_state(cpu);
        trace_hvf_unhandled_sysreg_read(env->pc, reg,
                                        SYSREG_OP0(reg),
                                        SYSREG_OP1(reg),
                                        SYSREG_CRN(reg),
                                        SYSREG_CRM(reg),
                                        SYSREG_OP2(reg));
        hvf_raise_exception(cpu, EXCP_UDEF, syn_uncategorized());
        return 1;
    }

    trace_hvf_sysreg_read(reg,
                          SYSREG_OP0(reg),
                          SYSREG_OP1(reg),
                          SYSREG_CRN(reg),
                          SYSREG_CRM(reg),
                          SYSREG_OP2(reg),
                          val);
    hvf_set_reg(cpu, rt, val);

    return 0;
}

static void pmu_update_irq(CPUARMState *env)
{
    ARMCPU *cpu = env_archcpu(env);
    qemu_set_irq(cpu->pmu_interrupt, (env->cp15.c9_pmcr & PMCRE) &&
            (env->cp15.c9_pminten & env->cp15.c9_pmovsr));
}

static bool pmu_event_supported(uint16_t number)
{
    return false;
}

/* Returns true if the counter (pass 31 for PMCCNTR) should count events using
 * the current EL, security state, and register configuration.
 */
static bool pmu_counter_enabled(CPUARMState *env, uint8_t counter)
{
    uint64_t filter;
    bool enabled, filtered = true;
    int el = arm_current_el(env);

    enabled = (env->cp15.c9_pmcr & PMCRE) &&
              (env->cp15.c9_pmcnten & (1 << counter));

    if (counter == 31) {
        filter = env->cp15.pmccfiltr_el0;
    } else {
        filter = env->cp15.c14_pmevtyper[counter];
    }

    if (el == 0) {
        filtered = filter & PMXEVTYPER_U;
    } else if (el == 1) {
        filtered = filter & PMXEVTYPER_P;
    }

    if (counter != 31) {
        /*
         * If not checking PMCCNTR, ensure the counter is setup to an event we
         * support
         */
        uint16_t event = filter & PMXEVTYPER_EVTCOUNT;
        if (!pmu_event_supported(event)) {
            return false;
        }
    }

    return enabled && !filtered;
}

static void pmswinc_write(CPUARMState *env, uint64_t value)
{
    unsigned int i;
    for (i = 0; i < pmu_num_counters(env); i++) {
        /* Increment a counter's count iff: */
        if ((value & (1 << i)) && /* counter's bit is set */
                /* counter is enabled and not filtered */
                pmu_counter_enabled(env, i) &&
                /* counter is SW_INCR */
                (env->cp15.c14_pmevtyper[i] & PMXEVTYPER_EVTCOUNT) == 0x0) {
            /*
             * Detect if this write causes an overflow since we can't predict
             * PMSWINC overflows like we can for other events
             */
            uint32_t new_pmswinc = env->cp15.c14_pmevcntr[i] + 1;

            if (env->cp15.c14_pmevcntr[i] & ~new_pmswinc & INT32_MIN) {
                env->cp15.c9_pmovsr |= (1 << i);
                pmu_update_irq(env);
            }

            env->cp15.c14_pmevcntr[i] = new_pmswinc;
        }
    }
}

static int hvf_sysreg_write(CPUState *cpu, uint32_t reg, uint64_t val)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    CPUARMState *env = &arm_cpu->env;

    trace_hvf_sysreg_write(reg,
                           SYSREG_OP0(reg),
                           SYSREG_OP1(reg),
                           SYSREG_CRN(reg),
                           SYSREG_CRM(reg),
                           SYSREG_OP2(reg),
                           val);

    switch (reg) {
    case SYSREG_PMCCNTR_EL0:
        pmu_op_start(env);
        env->cp15.c15_ccnt = val;
        pmu_op_finish(env);
        break;
    case SYSREG_PMCR_EL0:
        pmu_op_start(env);

        if (val & PMCRC) {
            /* The counter has been reset */
            env->cp15.c15_ccnt = 0;
        }

        if (val & PMCRP) {
            unsigned int i;
            for (i = 0; i < pmu_num_counters(env); i++) {
                env->cp15.c14_pmevcntr[i] = 0;
            }
        }

        env->cp15.c9_pmcr &= ~PMCR_WRITEABLE_MASK;
        env->cp15.c9_pmcr |= (val & PMCR_WRITEABLE_MASK);

        pmu_op_finish(env);
        break;
    case SYSREG_PMUSERENR_EL0:
        env->cp15.c9_pmuserenr = val & 0xf;
        break;
    case SYSREG_PMCNTENSET_EL0:
        env->cp15.c9_pmcnten |= (val & pmu_counter_mask(env));
        break;
    case SYSREG_PMCNTENCLR_EL0:
        env->cp15.c9_pmcnten &= ~(val & pmu_counter_mask(env));
        break;
    case SYSREG_PMINTENCLR_EL1:
        pmu_op_start(env);
        env->cp15.c9_pminten |= val;
        pmu_op_finish(env);
        break;
    case SYSREG_PMOVSCLR_EL0:
        pmu_op_start(env);
        env->cp15.c9_pmovsr &= ~val;
        pmu_op_finish(env);
        break;
    case SYSREG_PMSWINC_EL0:
        pmu_op_start(env);
        pmswinc_write(env, val);
        pmu_op_finish(env);
        break;
    case SYSREG_PMSELR_EL0:
        env->cp15.c9_pmselr = val & 0x1f;
        break;
    case SYSREG_PMCCFILTR_EL0:
        pmu_op_start(env);
        env->cp15.pmccfiltr_el0 = val & PMCCFILTR_EL0;
        pmu_op_finish(env);
        break;
    case SYSREG_OSLAR_EL1:
        env->cp15.oslsr_el1 = val & 1;
        break;
    case SYSREG_OSDLR_EL1:
        /* Dummy register */
        break;
    default:
        cpu_synchronize_state(cpu);
        trace_hvf_unhandled_sysreg_write(env->pc, reg,
                                         SYSREG_OP0(reg),
                                         SYSREG_OP1(reg),
                                         SYSREG_CRN(reg),
                                         SYSREG_CRM(reg),
                                         SYSREG_OP2(reg));
        hvf_raise_exception(cpu, EXCP_UDEF, syn_uncategorized());
        return 1;
    }

    return 0;
}

static int hvf_inject_interrupts(CPUState *cpu)
{
    if (cpu->interrupt_request & CPU_INTERRUPT_FIQ) {
        trace_hvf_inject_fiq();
        hv_vcpu_set_pending_interrupt(cpu->hvf->fd, HV_INTERRUPT_TYPE_FIQ,
                                      true);
    }

    if (cpu->interrupt_request & CPU_INTERRUPT_HARD) {
        trace_hvf_inject_irq();
        hv_vcpu_set_pending_interrupt(cpu->hvf->fd, HV_INTERRUPT_TYPE_IRQ,
                                      true);
    }

    return 0;
}

static uint64_t hvf_vtimer_val_raw(void)
{
    /*
     * mach_absolute_time() returns the vtimer value without the VM
     * offset that we define. Add our own offset on top.
     */
    return mach_absolute_time() - hvf_state->vtimer_offset;
}

static uint64_t hvf_vtimer_val(void)
{
    if (!runstate_is_running()) {
        /* VM is paused, the vtimer value is in vtimer.vtimer_val */
        return vtimer.vtimer_val;
    }

    return hvf_vtimer_val_raw();
}

static void hvf_wait_for_ipi(CPUState *cpu, struct timespec *ts)
{
    /*
     * Use pselect to sleep so that other threads can IPI us while we're
     * sleeping.
     */
    qatomic_mb_set(&cpu->thread_kicked, false);
    qemu_mutex_unlock_iothread();
    pselect(0, 0, 0, 0, ts, &cpu->hvf->unblock_ipi_mask);
    qemu_mutex_lock_iothread();
}

static void hvf_wfi(CPUState *cpu)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    struct timespec ts;
    hv_return_t r;
    uint64_t ctl;
    uint64_t cval;
    int64_t ticks_to_sleep;
    uint64_t seconds;
    uint64_t nanos;
    uint32_t cntfrq;

    if (cpu->interrupt_request & (CPU_INTERRUPT_HARD | CPU_INTERRUPT_FIQ)) {
        /* Interrupt pending, no need to wait */
        return;
    }

    r = hv_vcpu_get_sys_reg(cpu->hvf->fd, HV_SYS_REG_CNTV_CTL_EL0, &ctl);
    assert_hvf_ok(r);

    if (!(ctl & 1) || (ctl & 2)) {
        /* Timer disabled or masked, just wait for an IPI. */
        hvf_wait_for_ipi(cpu, NULL);
        return;
    }

    r = hv_vcpu_get_sys_reg(cpu->hvf->fd, HV_SYS_REG_CNTV_CVAL_EL0, &cval);
    assert_hvf_ok(r);

    ticks_to_sleep = cval - hvf_vtimer_val();
    if (ticks_to_sleep < 0) {
        return;
    }

    cntfrq = gt_cntfrq_period_ns(arm_cpu);
    seconds = muldiv64(ticks_to_sleep, cntfrq, NANOSECONDS_PER_SECOND);
    ticks_to_sleep -= muldiv64(seconds, NANOSECONDS_PER_SECOND, cntfrq);
    nanos = ticks_to_sleep * cntfrq;

    /*
     * Don't sleep for less than the time a context switch would take,
     * so that we can satisfy fast timer requests on the same CPU.
     * Measurements on M1 show the sweet spot to be ~2ms.
     */
    if (!seconds && nanos < (2 * SCALE_MS)) {
        return;
    }

    ts = (struct timespec) { seconds, nanos };
    hvf_wait_for_ipi(cpu, &ts);
}

static void hvf_sync_vtimer(CPUState *cpu)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    hv_return_t r;
    uint64_t ctl;
    bool irq_state;

    if (!cpu->hvf->vtimer_masked) {
        /* We will get notified on vtimer changes by hvf, nothing to do */
        return;
    }

    r = hv_vcpu_get_sys_reg(cpu->hvf->fd, HV_SYS_REG_CNTV_CTL_EL0, &ctl);
    assert_hvf_ok(r);

    irq_state = (ctl & (TMR_CTL_ENABLE | TMR_CTL_IMASK | TMR_CTL_ISTATUS)) ==
                (TMR_CTL_ENABLE | TMR_CTL_ISTATUS);
    qemu_set_irq(arm_cpu->gt_timer_outputs[GTIMER_VIRT], irq_state);

    if (!irq_state) {
        /* Timer no longer asserting, we can unmask it */
        hv_vcpu_set_vtimer_mask(cpu->hvf->fd, false);
        cpu->hvf->vtimer_masked = false;
    }
}

int hvf_vcpu_exec(CPUState *cpu)
{
    ARMCPU *arm_cpu = ARM_CPU(cpu);
    CPUARMState *env = &arm_cpu->env;
    hv_vcpu_exit_t *hvf_exit = cpu->hvf->exit;
    hv_return_t r;
    bool advance_pc = false;

    if (hvf_inject_interrupts(cpu)) {
        return EXCP_INTERRUPT;
    }

    if (cpu->halted) {
        return EXCP_HLT;
    }

    flush_cpu_state(cpu);

    qemu_mutex_unlock_iothread();
    assert_hvf_ok(hv_vcpu_run(cpu->hvf->fd));

    /* handle VMEXIT */
    uint64_t exit_reason = hvf_exit->reason;
    uint64_t syndrome = hvf_exit->exception.syndrome;
    uint32_t ec = syn_get_ec(syndrome);

    qemu_mutex_lock_iothread();
    switch (exit_reason) {
    case HV_EXIT_REASON_EXCEPTION:
        /* This is the main one, handle below. */
        break;
    case HV_EXIT_REASON_VTIMER_ACTIVATED:
        qemu_set_irq(arm_cpu->gt_timer_outputs[GTIMER_VIRT], 1);
        cpu->hvf->vtimer_masked = true;
        return 0;
    case HV_EXIT_REASON_CANCELED:
        /* we got kicked, no exit to process */
        return 0;
    default:
        assert(0);
    }

    hvf_sync_vtimer(cpu);

    switch (ec) {
    case EC_DATAABORT: {
        bool isv = syndrome & ARM_EL_ISV;
        bool iswrite = (syndrome >> 6) & 1;
        bool s1ptw = (syndrome >> 7) & 1;
        uint32_t sas = (syndrome >> 22) & 3;
        uint32_t len = 1 << sas;
        uint32_t srt = (syndrome >> 16) & 0x1f;
        uint32_t cm = (syndrome >> 8) & 0x1;
        uint64_t val = 0;

        trace_hvf_data_abort(env->pc, hvf_exit->exception.virtual_address,
                             hvf_exit->exception.physical_address, isv,
                             iswrite, s1ptw, len, srt);

        if (cm) {
            /* We don't cache MMIO regions */
            advance_pc = true;
            break;
        }

        assert(isv);

        if (iswrite) {
            val = hvf_get_reg(cpu, srt);
            address_space_write(&address_space_memory,
                                hvf_exit->exception.physical_address,
                                MEMTXATTRS_UNSPECIFIED, &val, len);
        } else {
            address_space_read(&address_space_memory,
                               hvf_exit->exception.physical_address,
                               MEMTXATTRS_UNSPECIFIED, &val, len);
            hvf_set_reg(cpu, srt, val);
        }

        advance_pc = true;
        break;
    }
    case EC_SYSTEMREGISTERTRAP: {
        bool isread = (syndrome >> 0) & 1;
        uint32_t rt = (syndrome >> 5) & 0x1f;
        uint32_t reg = syndrome & SYSREG_MASK;
        uint64_t val;
        int ret = 0;

        if (isread) {
            ret = hvf_sysreg_read(cpu, reg, rt);
        } else {
            val = hvf_get_reg(cpu, rt);
            ret = hvf_sysreg_write(cpu, reg, val);
        }

        advance_pc = !ret;
        break;
    }
    case EC_WFX_TRAP:
        advance_pc = true;
        if (!(syndrome & WFX_IS_WFE)) {
            hvf_wfi(cpu);
        }
        break;
    case EC_AA64_HVC:
        cpu_synchronize_state(cpu);
        if (arm_cpu->psci_conduit == QEMU_PSCI_CONDUIT_HVC) {
            if (!hvf_handle_psci_call(cpu)) {
                trace_hvf_unknown_hvc(env->xregs[0]);
                /* SMCCC 1.3 section 5.2 says every unknown SMCCC call returns -1 */
                env->xregs[0] = -1;
            }
        } else {
            trace_hvf_unknown_hvc(env->xregs[0]);
            hvf_raise_exception(cpu, EXCP_UDEF, syn_uncategorized());
        }
        break;
    case EC_AA64_SMC:
        cpu_synchronize_state(cpu);
        if (arm_cpu->psci_conduit == QEMU_PSCI_CONDUIT_SMC) {
            advance_pc = true;

            if (!hvf_handle_psci_call(cpu)) {
                trace_hvf_unknown_smc(env->xregs[0]);
                /* SMCCC 1.3 section 5.2 says every unknown SMCCC call returns -1 */
                env->xregs[0] = -1;
            }
        } else {
            trace_hvf_unknown_smc(env->xregs[0]);
            hvf_raise_exception(cpu, EXCP_UDEF, syn_uncategorized());
        }
        break;
    default:
        cpu_synchronize_state(cpu);
        trace_hvf_exit(syndrome, ec, env->pc);
        error_report("0x%llx: unhandled exception ec=0x%x", env->pc, ec);
    }

    if (advance_pc) {
        uint64_t pc;

        flush_cpu_state(cpu);

        r = hv_vcpu_get_reg(cpu->hvf->fd, HV_REG_PC, &pc);
        assert_hvf_ok(r);
        pc += 4;
        r = hv_vcpu_set_reg(cpu->hvf->fd, HV_REG_PC, pc);
        assert_hvf_ok(r);
    }

    return 0;
}

static const VMStateDescription vmstate_hvf_vtimer = {
    .name = "hvf-vtimer",
    .version_id = 1,
    .minimum_version_id = 1,
    .fields = (VMStateField[]) {
        VMSTATE_UINT64(vtimer_val, HVFVTimer),
        VMSTATE_END_OF_LIST()
    },
};

static void hvf_vm_state_change(void *opaque, bool running, RunState state)
{
    HVFVTimer *s = opaque;

    if (running) {
        /* Update vtimer offset on all CPUs */
        hvf_state->vtimer_offset = mach_absolute_time() - s->vtimer_val;
        cpu_synchronize_all_states();
    } else {
        /* Remember vtimer value on every pause */
        s->vtimer_val = hvf_vtimer_val_raw();
    }
}

int hvf_arch_init(void)
{
    hvf_state->vtimer_offset = mach_absolute_time();
    vmstate_register(NULL, 0, &vmstate_hvf_vtimer, &vtimer);
    qemu_add_vm_change_state_handler(hvf_vm_state_change, &vtimer);
    return 0;
}