#include "qemu/osdep.h"
#include "hw/hw.h"
#include "hw/boards.h"
#include "qemu/error-report.h"
#include "sysemu/kvm.h"
#include "kvm_arm.h"
#include "internals.h"
#include "migration/cpu.h"

static bool vfp_needed(void *opaque)
{
    ARMCPU *cpu = opaque;
    CPUARMState *env = &cpu->env;

    return arm_feature(env, ARM_FEATURE_VFP);
}

static int get_fpscr(QEMUFile *f, void *opaque, size_t size)
{
    ARMCPU *cpu = opaque;
    CPUARMState *env = &cpu->env;
    uint32_t val = qemu_get_be32(f);

    vfp_set_fpscr(env, val);
    return 0;
}

static void put_fpscr(QEMUFile *f, void *opaque, size_t size)
{
    ARMCPU *cpu = opaque;
    CPUARMState *env = &cpu->env;

    qemu_put_be32(f, vfp_get_fpscr(env));
}

static const VMStateInfo vmstate_fpscr = {
    .name = "fpscr",
    .get = get_fpscr,
    .put = put_fpscr,
};

static const VMStateDescription vmstate_vfp = {
    .name = "cpu/vfp",
    .version_id = 3,
    .minimum_version_id = 3,
    .needed = vfp_needed,
    .fields = (VMStateField[]) {
        VMSTATE_FLOAT64_ARRAY(env.vfp.regs, ARMCPU, 64),
        /* The xregs array is a little awkward because element 1 (FPSCR)
         * requires a specific accessor, so we have to split it up in
         * the vmstate:
         */
        VMSTATE_UINT32(env.vfp.xregs[0], ARMCPU),
        VMSTATE_UINT32_SUB_ARRAY(env.vfp.xregs, ARMCPU, 2, 14),
        {
            .name = "fpscr",
            .version_id = 0,
            .size = sizeof(uint32_t),
            .info = &vmstate_fpscr,
            .flags = VMS_SINGLE,
            .offset = 0,
        },
        VMSTATE_END_OF_LIST()
    }
};

static bool iwmmxt_needed(void *opaque)
{
    ARMCPU *cpu = opaque;
    CPUARMState *env = &cpu->env;

    return arm_feature(env, ARM_FEATURE_IWMMXT);
}

static const VMStateDescription vmstate_iwmmxt = {
    .name = "cpu/iwmmxt",
    .version_id = 1,
    .minimum_version_id = 1,
    .needed = iwmmxt_needed,
    .fields = (VMStateField[]) {
        VMSTATE_UINT64_ARRAY(env.iwmmxt.regs, ARMCPU, 16),
        VMSTATE_UINT32_ARRAY(env.iwmmxt.cregs, ARMCPU, 16),
        VMSTATE_END_OF_LIST()
    }
};

static bool m_needed(void *opaque)
{
    ARMCPU *cpu = opaque;
    CPUARMState *env = &cpu->env;

    return arm_feature(env, ARM_FEATURE_M);
}

static const VMStateDescription vmstate_m = {
    .name = "cpu/m",
    .version_id = 1,
    .minimum_version_id = 1,
    .needed = m_needed,
    .fields = (VMStateField[]) {
        VMSTATE_UINT32(env.v7m.other_sp, ARMCPU),
        VMSTATE_UINT32(env.v7m.vecbase, ARMCPU),
        VMSTATE_UINT32(env.v7m.basepri, ARMCPU),
        VMSTATE_UINT32(env.v7m.control, ARMCPU),
        VMSTATE_INT32(env.v7m.current_sp, ARMCPU),
        VMSTATE_INT32(env.v7m.exception, ARMCPU),
        VMSTATE_END_OF_LIST()
    }
};

static bool thumb2ee_needed(void *opaque)
{
    ARMCPU *cpu = opaque;
    CPUARMState *env = &cpu->env;

    return arm_feature(env, ARM_FEATURE_THUMB2EE);
}

static const VMStateDescription vmstate_thumb2ee = {
    .name = "cpu/thumb2ee",
    .version_id = 1,
    .minimum_version_id = 1,
    .needed = thumb2ee_needed,
    .fields = (VMStateField[]) {
        VMSTATE_UINT32(env.teecr, ARMCPU),
        VMSTATE_UINT32(env.teehbr, ARMCPU),
        VMSTATE_END_OF_LIST()
    }
};

static bool pmsav7_needed(void *opaque)
{
    ARMCPU *cpu = opaque;
    CPUARMState *env = &cpu->env;

    return arm_feature(env, ARM_FEATURE_MPU) &&
           arm_feature(env, ARM_FEATURE_V7);
}

static bool pmsav7_rgnr_vmstate_validate(void *opaque, int version_id)
{
    ARMCPU *cpu = opaque;

    return cpu->env.cp15.c6_rgnr < cpu->pmsav7_dregion;
}

static const VMStateDescription vmstate_pmsav7 = {
    .name = "cpu/pmsav7",
    .version_id = 1,
    .minimum_version_id = 1,
    .needed = pmsav7_needed,
    .fields = (VMStateField[]) {
        VMSTATE_VARRAY_UINT32(env.pmsav7.drbar, ARMCPU, pmsav7_dregion, 0,
                              vmstate_info_uint32, uint32_t),
        VMSTATE_VARRAY_UINT32(env.pmsav7.drsr, ARMCPU, pmsav7_dregion, 0,
                              vmstate_info_uint32, uint32_t),
        VMSTATE_VARRAY_UINT32(env.pmsav7.dracr, ARMCPU, pmsav7_dregion, 0,
                              vmstate_info_uint32, uint32_t),
        VMSTATE_VALIDATE("rgnr is valid", pmsav7_rgnr_vmstate_validate),
        VMSTATE_END_OF_LIST()
    }
};

static int get_cpsr(QEMUFile *f, void *opaque, size_t size)
{
    ARMCPU *cpu = opaque;
    CPUARMState *env = &cpu->env;
    uint32_t val = qemu_get_be32(f);

    env->aarch64 = ((val & PSTATE_nRW) == 0);

    if (is_a64(env)) {
        pstate_write(env, val);
        return 0;
    }

    cpsr_write(env, val, 0xffffffff, CPSRWriteRaw);
    return 0;
}

static void put_cpsr(QEMUFile *f, void *opaque, size_t size)
{
    ARMCPU *cpu = opaque;
    CPUARMState *env = &cpu->env;
    uint32_t val;

    if (is_a64(env)) {
        val = pstate_read(env);
    } else {
        val = cpsr_read(env);
    }

    qemu_put_be32(f, val);
}

static const VMStateInfo vmstate_cpsr = {
    .name = "cpsr",
    .get = get_cpsr,
    .put = put_cpsr,
};

static void cpu_pre_save(void *opaque)
{
    ARMCPU *cpu = opaque;

    if (kvm_enabled()) {
        if (!write_kvmstate_to_list(cpu)) {
            /* This should never fail */
            abort();
        }
    } else {
        if (!write_cpustate_to_list(cpu)) {
            /* This should never fail. */
            abort();
        }
    }

    cpu->cpreg_vmstate_array_len = cpu->cpreg_array_len;
    memcpy(cpu->cpreg_vmstate_indexes, cpu->cpreg_indexes,
           cpu->cpreg_array_len * sizeof(uint64_t));
    memcpy(cpu->cpreg_vmstate_values, cpu->cpreg_values,
           cpu->cpreg_array_len * sizeof(uint64_t));
}

static int cpu_post_load(void *opaque, int version_id)
{
    ARMCPU *cpu = opaque;
    int i, v;

    /* Update the values list from the incoming migration data.
     * Anything in the incoming data which we don't know about is
     * a migration failure; anything we know about but the incoming
     * data doesn't specify retains its current (reset) value.
     * The indexes list remains untouched -- we only inspect the
     * incoming migration index list so we can match the values array
     * entries with the right slots in our own values array.
     */

    for (i = 0, v = 0; i < cpu->cpreg_array_len
             && v < cpu->cpreg_vmstate_array_len; i++) {
        if (cpu->cpreg_vmstate_indexes[v] > cpu->cpreg_indexes[i]) {
            /* register in our list but not incoming : skip it */
            continue;
        }
        if (cpu->cpreg_vmstate_indexes[v] < cpu->cpreg_indexes[i]) {
            /* register in their list but not ours: fail migration */
            return -1;
        }
        /* matching register, copy the value over */
        cpu->cpreg_values[i] = cpu->cpreg_vmstate_values[v];
        v++;
    }

    if (kvm_enabled()) {
        if (!write_list_to_kvmstate(cpu, KVM_PUT_FULL_STATE)) {
            return -1;
        }
        /* Note that it's OK for the TCG side not to know about
         * every register in the list; KVM is authoritative if
         * we're using it.
         */
        write_list_to_cpustate(cpu);
    } else {
        if (!write_list_to_cpustate(cpu)) {
            return -1;
        }
    }

    hw_breakpoint_update_all(cpu);
    hw_watchpoint_update_all(cpu);

    return 0;
}

const VMStateDescription vmstate_arm_cpu = {
    .name = "cpu",
    .version_id = 22,
    .minimum_version_id = 22,
    .pre_save = cpu_pre_save,
    .post_load = cpu_post_load,
    .fields = (VMStateField[]) {
        VMSTATE_UINT32_ARRAY(env.regs, ARMCPU, 16),
        VMSTATE_UINT64_ARRAY(env.xregs, ARMCPU, 32),
        VMSTATE_UINT64(env.pc, ARMCPU),
        {
            .name = "cpsr",
            .version_id = 0,
            .size = sizeof(uint32_t),
            .info = &vmstate_cpsr,
            .flags = VMS_SINGLE,
            .offset = 0,
        },
        VMSTATE_UINT32(env.spsr, ARMCPU),
        VMSTATE_UINT64_ARRAY(env.banked_spsr, ARMCPU, 8),
        VMSTATE_UINT32_ARRAY(env.banked_r13, ARMCPU, 8),
        VMSTATE_UINT32_ARRAY(env.banked_r14, ARMCPU, 8),
        VMSTATE_UINT32_ARRAY(env.usr_regs, ARMCPU, 5),
        VMSTATE_UINT32_ARRAY(env.fiq_regs, ARMCPU, 5),
        VMSTATE_UINT64_ARRAY(env.elr_el, ARMCPU, 4),
        VMSTATE_UINT64_ARRAY(env.sp_el, ARMCPU, 4),
        /* The length-check must come before the arrays to avoid
         * incoming data possibly overflowing the array.
         */
        VMSTATE_INT32_POSITIVE_LE(cpreg_vmstate_array_len, ARMCPU),
        VMSTATE_VARRAY_INT32(cpreg_vmstate_indexes, ARMCPU,
                             cpreg_vmstate_array_len,
                             0, vmstate_info_uint64, uint64_t),
        VMSTATE_VARRAY_INT32(cpreg_vmstate_values, ARMCPU,
                             cpreg_vmstate_array_len,
                             0, vmstate_info_uint64, uint64_t),
        VMSTATE_UINT64(env.exclusive_addr, ARMCPU),
        VMSTATE_UINT64(env.exclusive_val, ARMCPU),
        VMSTATE_UINT64(env.exclusive_high, ARMCPU),
        VMSTATE_UINT64(env.features, ARMCPU),
        VMSTATE_UINT32(env.exception.syndrome, ARMCPU),
        VMSTATE_UINT32(env.exception.fsr, ARMCPU),
        VMSTATE_UINT64(env.exception.vaddress, ARMCPU),
        VMSTATE_TIMER_PTR(gt_timer[GTIMER_PHYS], ARMCPU),
        VMSTATE_TIMER_PTR(gt_timer[GTIMER_VIRT], ARMCPU),
        VMSTATE_BOOL(powered_off, ARMCPU),
        VMSTATE_END_OF_LIST()
    },
    .subsections = (const VMStateDescription*[]) {
        &vmstate_vfp,
        &vmstate_iwmmxt,
        &vmstate_m,
        &vmstate_thumb2ee,
        &vmstate_pmsav7,
        NULL
    }
};

const char *gicv3_class_name(void)
{
    if (kvm_irqchip_in_kernel()) {
#ifdef TARGET_AARCH64
        return "kvm-arm-gicv3";
#else
        error_report("KVM GICv3 acceleration is not supported on this "
                     "platform");
#endif
    } else {
        /* TODO: Software emulation is not implemented yet */
        error_report("KVM is currently required for GICv3 emulation");
    }

    exit(1);
}