/*
 *  x86 misc helpers
 *
 *  Copyright (c) 2003 Fabrice Bellard
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */

#include "cpu.h"
#include "exec/ioport.h"
#include "helper.h"

#if !defined(CONFIG_USER_ONLY)
#include "exec/softmmu_exec.h"
#endif /* !defined(CONFIG_USER_ONLY) */

/* check if Port I/O is allowed in TSS */
static inline void check_io(CPUX86State *env, int addr, int size)
{
    int io_offset, val, mask;

    /* TSS must be a valid 32 bit one */
    if (!(env->tr.flags & DESC_P_MASK) ||
        ((env->tr.flags >> DESC_TYPE_SHIFT) & 0xf) != 9 ||
        env->tr.limit < 103) {
        goto fail;
    }
    io_offset = cpu_lduw_kernel(env, env->tr.base + 0x66);
    io_offset += (addr >> 3);
    /* Note: the check needs two bytes */
    if ((io_offset + 1) > env->tr.limit) {
        goto fail;
    }
    val = cpu_lduw_kernel(env, env->tr.base + io_offset);
    val >>= (addr & 7);
    mask = (1 << size) - 1;
    /* all bits must be zero to allow the I/O */
    if ((val & mask) != 0) {
    fail:
        raise_exception_err(env, EXCP0D_GPF, 0);
    }
}

void helper_check_iob(CPUX86State *env, uint32_t t0)
{
    check_io(env, t0, 1);
}

void helper_check_iow(CPUX86State *env, uint32_t t0)
{
    check_io(env, t0, 2);
}

void helper_check_iol(CPUX86State *env, uint32_t t0)
{
    check_io(env, t0, 4);
}

void helper_outb(uint32_t port, uint32_t data)
{
    cpu_outb(port, data & 0xff);
}

target_ulong helper_inb(uint32_t port)
{
    return cpu_inb(port);
}

void helper_outw(uint32_t port, uint32_t data)
{
    cpu_outw(port, data & 0xffff);
}

target_ulong helper_inw(uint32_t port)
{
    return cpu_inw(port);
}

void helper_outl(uint32_t port, uint32_t data)
{
    cpu_outl(port, data);
}

target_ulong helper_inl(uint32_t port)
{
    return cpu_inl(port);
}

void helper_into(CPUX86State *env, int next_eip_addend)
{
    int eflags;
    eflags = helper_cc_compute_all(env, CC_OP);
    if (eflags & CC_O) {
        raise_interrupt(env, EXCP04_INTO, 1, 0, next_eip_addend);
    }
}

void helper_single_step(CPUX86State *env)
{
#ifndef CONFIG_USER_ONLY
    check_hw_breakpoints(env, 1);
    env->dr[6] |= DR6_BS;
#endif
    raise_exception(env, EXCP01_DB);
}

void helper_cpuid(CPUX86State *env)
{
    uint32_t eax, ebx, ecx, edx;

    helper_svm_check_intercept_param(env, SVM_EXIT_CPUID, 0);

    cpu_x86_cpuid(env, (uint32_t)env->regs[R_EAX], (uint32_t)env->regs[R_ECX],
                  &eax, &ebx, &ecx, &edx);
    env->regs[R_EAX] = eax;
    env->regs[R_EBX] = ebx;
    env->regs[R_ECX] = ecx;
    env->regs[R_EDX] = edx;
}

#if defined(CONFIG_USER_ONLY)
target_ulong helper_read_crN(CPUX86State *env, int reg)
{
    return 0;
}

void helper_write_crN(CPUX86State *env, int reg, target_ulong t0)
{
}

void helper_movl_drN_T0(CPUX86State *env, int reg, target_ulong t0)
{
}
#else
target_ulong helper_read_crN(CPUX86State *env, int reg)
{
    target_ulong val;

    helper_svm_check_intercept_param(env, SVM_EXIT_READ_CR0 + reg, 0);
    switch(reg) {
    default:
        val = env->cr[reg];
        break;
    case 8:
        if (!(env->hflags2 & HF2_VINTR_MASK)) {
            val = cpu_get_apic_tpr(env);
        } else {
            val = env->v_tpr;
        }
        break;
    }
    return val;
}

void helper_write_crN(CPUX86State *env, int reg, target_ulong t0)
{
    helper_svm_check_intercept_param(env, SVM_EXIT_WRITE_CR0 + reg, 0);
    switch(reg) {
    case 0:
        cpu_x86_update_cr0(env, t0);
        break;
    case 3:
        cpu_x86_update_cr3(env, t0);
        break;
    case 4:
        cpu_x86_update_cr4(env, t0);
        break;
    case 8:
        if (!(env->hflags2 & HF2_VINTR_MASK)) {
            cpu_set_apic_tpr(env, t0);
        }
        env->v_tpr = t0 & 0x0f;
        break;
    default:
        env->cr[reg] = t0;
        break;
    }
}

void helper_movl_drN_T0(CPUX86State *env, int reg, target_ulong t0)
{
    int i;

    if (reg < 4) {
        hw_breakpoint_remove(env, reg);
        env->dr[reg] = t0;
        hw_breakpoint_insert(env, reg);
    } else if (reg == 7) {
        for (i = 0; i < 4; i++) {
            hw_breakpoint_remove(env, i);
        }
        env->dr[7] = t0;
        for (i = 0; i < 4; i++) {
            hw_breakpoint_insert(env, i);
        }
    } else {
        env->dr[reg] = t0;
    }
}
#endif

void helper_lmsw(CPUX86State *env, target_ulong t0)
{
    /* only 4 lower bits of CR0 are modified. PE cannot be set to zero
       if already set to one. */
    t0 = (env->cr[0] & ~0xe) | (t0 & 0xf);
    helper_write_crN(env, 0, t0);
}

void helper_invlpg(CPUX86State *env, target_ulong addr)
{
    helper_svm_check_intercept_param(env, SVM_EXIT_INVLPG, 0);
    tlb_flush_page(env, addr);
}

void helper_rdtsc(CPUX86State *env)
{
    uint64_t val;

    if ((env->cr[4] & CR4_TSD_MASK) && ((env->hflags & HF_CPL_MASK) != 0)) {
        raise_exception(env, EXCP0D_GPF);
    }
    helper_svm_check_intercept_param(env, SVM_EXIT_RDTSC, 0);

    val = cpu_get_tsc(env) + env->tsc_offset;
    env->regs[R_EAX] = (uint32_t)(val);
    env->regs[R_EDX] = (uint32_t)(val >> 32);
}

void helper_rdpmc(CPUX86State *env)
{
    if ((env->cr[4] & CR4_PCE_MASK) && ((env->hflags & HF_CPL_MASK) != 0)) {
        raise_exception(env, EXCP0D_GPF);
    }
    helper_svm_check_intercept_param(env, SVM_EXIT_RDPMC, 0);

    /* currently unimplemented */
    raise_exception_err(env, EXCP06_ILLOP, 0);
}

#if defined(CONFIG_USER_ONLY)
void helper_wrmsr(CPUX86State *env)
{
}

void helper_rdmsr(CPUX86State *env)
{
}
#else
void helper_wrmsr(CPUX86State *env)
{
    uint64_t val;

    helper_svm_check_intercept_param(env, SVM_EXIT_MSR, 1);

    val = ((uint32_t)env->regs[R_EAX]) |
        ((uint64_t)((uint32_t)env->regs[R_EDX]) << 32);

    switch ((uint32_t)env->regs[R_ECX]) {
    case MSR_IA32_SYSENTER_CS:
        env->sysenter_cs = val & 0xffff;
        break;
    case MSR_IA32_SYSENTER_ESP:
        env->sysenter_esp = val;
        break;
    case MSR_IA32_SYSENTER_EIP:
        env->sysenter_eip = val;
        break;
    case MSR_IA32_APICBASE:
        cpu_set_apic_base(env, val);
        break;
    case MSR_EFER:
        {
            uint64_t update_mask;
            update_mask = 0;
            if (env->cpuid_ext2_features & CPUID_EXT2_SYSCALL) {
                update_mask |= MSR_EFER_SCE;
            }
            if (env->cpuid_ext2_features & CPUID_EXT2_LM) {
                update_mask |= MSR_EFER_LME;
            }
            if (env->cpuid_ext2_features & CPUID_EXT2_FFXSR) {
                update_mask |= MSR_EFER_FFXSR;
            }
            if (env->cpuid_ext2_features & CPUID_EXT2_NX) {
                update_mask |= MSR_EFER_NXE;
            }
            if (env->cpuid_ext3_features & CPUID_EXT3_SVM) {
                update_mask |= MSR_EFER_SVME;
            }
            if (env->cpuid_ext2_features & CPUID_EXT2_FFXSR) {
                update_mask |= MSR_EFER_FFXSR;
            }
            cpu_load_efer(env, (env->efer & ~update_mask) |
                          (val & update_mask));
        }
        break;
    case MSR_STAR:
        env->star = val;
        break;
    case MSR_PAT:
        env->pat = val;
        break;
    case MSR_VM_HSAVE_PA:
        env->vm_hsave = val;
        break;
#ifdef TARGET_X86_64
    case MSR_LSTAR:
        env->lstar = val;
        break;
    case MSR_CSTAR:
        env->cstar = val;
        break;
    case MSR_FMASK:
        env->fmask = val;
        break;
    case MSR_FSBASE:
        env->segs[R_FS].base = val;
        break;
    case MSR_GSBASE:
        env->segs[R_GS].base = val;
        break;
    case MSR_KERNELGSBASE:
        env->kernelgsbase = val;
        break;
#endif
    case MSR_MTRRphysBase(0):
    case MSR_MTRRphysBase(1):
    case MSR_MTRRphysBase(2):
    case MSR_MTRRphysBase(3):
    case MSR_MTRRphysBase(4):
    case MSR_MTRRphysBase(5):
    case MSR_MTRRphysBase(6):
    case MSR_MTRRphysBase(7):
        env->mtrr_var[((uint32_t)env->regs[R_ECX] -
                       MSR_MTRRphysBase(0)) / 2].base = val;
        break;
    case MSR_MTRRphysMask(0):
    case MSR_MTRRphysMask(1):
    case MSR_MTRRphysMask(2):
    case MSR_MTRRphysMask(3):
    case MSR_MTRRphysMask(4):
    case MSR_MTRRphysMask(5):
    case MSR_MTRRphysMask(6):
    case MSR_MTRRphysMask(7):
        env->mtrr_var[((uint32_t)env->regs[R_ECX] -
                       MSR_MTRRphysMask(0)) / 2].mask = val;
        break;
    case MSR_MTRRfix64K_00000:
        env->mtrr_fixed[(uint32_t)env->regs[R_ECX] -
                        MSR_MTRRfix64K_00000] = val;
        break;
    case MSR_MTRRfix16K_80000:
    case MSR_MTRRfix16K_A0000:
        env->mtrr_fixed[(uint32_t)env->regs[R_ECX] -
                        MSR_MTRRfix16K_80000 + 1] = val;
        break;
    case MSR_MTRRfix4K_C0000:
    case MSR_MTRRfix4K_C8000:
    case MSR_MTRRfix4K_D0000:
    case MSR_MTRRfix4K_D8000:
    case MSR_MTRRfix4K_E0000:
    case MSR_MTRRfix4K_E8000:
    case MSR_MTRRfix4K_F0000:
    case MSR_MTRRfix4K_F8000:
        env->mtrr_fixed[(uint32_t)env->regs[R_ECX] -
                        MSR_MTRRfix4K_C0000 + 3] = val;
        break;
    case MSR_MTRRdefType:
        env->mtrr_deftype = val;
        break;
    case MSR_MCG_STATUS:
        env->mcg_status = val;
        break;
    case MSR_MCG_CTL:
        if ((env->mcg_cap & MCG_CTL_P)
            && (val == 0 || val == ~(uint64_t)0)) {
            env->mcg_ctl = val;
        }
        break;
    default:
        if ((uint32_t)env->regs[R_ECX] >= MSR_MC0_CTL
            && (uint32_t)env->regs[R_ECX] < MSR_MC0_CTL +
            (4 * env->mcg_cap & 0xff)) {
            uint32_t offset = (uint32_t)env->regs[R_ECX] - MSR_MC0_CTL;
            if ((offset & 0x3) != 0
                || (val == 0 || val == ~(uint64_t)0)) {
                env->mce_banks[offset] = val;
            }
            break;
        }
        /* XXX: exception ? */
        break;
    }
}

void helper_rdmsr(CPUX86State *env)
{
    uint64_t val;

    helper_svm_check_intercept_param(env, SVM_EXIT_MSR, 0);

    switch ((uint32_t)env->regs[R_ECX]) {
    case MSR_IA32_SYSENTER_CS:
        val = env->sysenter_cs;
        break;
    case MSR_IA32_SYSENTER_ESP:
        val = env->sysenter_esp;
        break;
    case MSR_IA32_SYSENTER_EIP:
        val = env->sysenter_eip;
        break;
    case MSR_IA32_APICBASE:
        val = cpu_get_apic_base(env);
        break;
    case MSR_EFER:
        val = env->efer;
        break;
    case MSR_STAR:
        val = env->star;
        break;
    case MSR_PAT:
        val = env->pat;
        break;
    case MSR_VM_HSAVE_PA:
        val = env->vm_hsave;
        break;
    case MSR_IA32_PERF_STATUS:
        /* tsc_increment_by_tick */
        val = 1000ULL;
        /* CPU multiplier */
        val |= (((uint64_t)4ULL) << 40);
        break;
#ifdef TARGET_X86_64
    case MSR_LSTAR:
        val = env->lstar;
        break;
    case MSR_CSTAR:
        val = env->cstar;
        break;
    case MSR_FMASK:
        val = env->fmask;
        break;
    case MSR_FSBASE:
        val = env->segs[R_FS].base;
        break;
    case MSR_GSBASE:
        val = env->segs[R_GS].base;
        break;
    case MSR_KERNELGSBASE:
        val = env->kernelgsbase;
        break;
#endif
    case MSR_MTRRphysBase(0):
    case MSR_MTRRphysBase(1):
    case MSR_MTRRphysBase(2):
    case MSR_MTRRphysBase(3):
    case MSR_MTRRphysBase(4):
    case MSR_MTRRphysBase(5):
    case MSR_MTRRphysBase(6):
    case MSR_MTRRphysBase(7):
        val = env->mtrr_var[((uint32_t)env->regs[R_ECX] -
                             MSR_MTRRphysBase(0)) / 2].base;
        break;
    case MSR_MTRRphysMask(0):
    case MSR_MTRRphysMask(1):
    case MSR_MTRRphysMask(2):
    case MSR_MTRRphysMask(3):
    case MSR_MTRRphysMask(4):
    case MSR_MTRRphysMask(5):
    case MSR_MTRRphysMask(6):
    case MSR_MTRRphysMask(7):
        val = env->mtrr_var[((uint32_t)env->regs[R_ECX] -
                             MSR_MTRRphysMask(0)) / 2].mask;
        break;
    case MSR_MTRRfix64K_00000:
        val = env->mtrr_fixed[0];
        break;
    case MSR_MTRRfix16K_80000:
    case MSR_MTRRfix16K_A0000:
        val = env->mtrr_fixed[(uint32_t)env->regs[R_ECX] -
                              MSR_MTRRfix16K_80000 + 1];
        break;
    case MSR_MTRRfix4K_C0000:
    case MSR_MTRRfix4K_C8000:
    case MSR_MTRRfix4K_D0000:
    case MSR_MTRRfix4K_D8000:
    case MSR_MTRRfix4K_E0000:
    case MSR_MTRRfix4K_E8000:
    case MSR_MTRRfix4K_F0000:
    case MSR_MTRRfix4K_F8000:
        val = env->mtrr_fixed[(uint32_t)env->regs[R_ECX] -
                              MSR_MTRRfix4K_C0000 + 3];
        break;
    case MSR_MTRRdefType:
        val = env->mtrr_deftype;
        break;
    case MSR_MTRRcap:
        if (env->cpuid_features & CPUID_MTRR) {
            val = MSR_MTRRcap_VCNT | MSR_MTRRcap_FIXRANGE_SUPPORT | MSR_MTRRcap_WC_SUPPORTED;
        } else {
            /* XXX: exception ? */
            val = 0;
        }
        break;
    case MSR_MCG_CAP:
        val = env->mcg_cap;
        break;
    case MSR_MCG_CTL:
        if (env->mcg_cap & MCG_CTL_P) {
            val = env->mcg_ctl;
        } else {
            val = 0;
        }
        break;
    case MSR_MCG_STATUS:
        val = env->mcg_status;
        break;
    default:
        if ((uint32_t)env->regs[R_ECX] >= MSR_MC0_CTL
            && (uint32_t)env->regs[R_ECX] < MSR_MC0_CTL +
            (4 * env->mcg_cap & 0xff)) {
            uint32_t offset = (uint32_t)env->regs[R_ECX] - MSR_MC0_CTL;
            val = env->mce_banks[offset];
            break;
        }
        /* XXX: exception ? */
        val = 0;
        break;
    }
    env->regs[R_EAX] = (uint32_t)(val);
    env->regs[R_EDX] = (uint32_t)(val >> 32);
}
#endif

static void do_hlt(CPUX86State *env)
{
    env->hflags &= ~HF_INHIBIT_IRQ_MASK; /* needed if sti is just before */
    ENV_GET_CPU(env)->halted = 1;
    env->exception_index = EXCP_HLT;
    cpu_loop_exit(env);
}

void helper_hlt(CPUX86State *env, int next_eip_addend)
{
    helper_svm_check_intercept_param(env, SVM_EXIT_HLT, 0);
    env->eip += next_eip_addend;

    do_hlt(env);
}

void helper_monitor(CPUX86State *env, target_ulong ptr)
{
    if ((uint32_t)env->regs[R_ECX] != 0) {
        raise_exception(env, EXCP0D_GPF);
    }
    /* XXX: store address ? */
    helper_svm_check_intercept_param(env, SVM_EXIT_MONITOR, 0);
}

void helper_mwait(CPUX86State *env, int next_eip_addend)
{
    if ((uint32_t)env->regs[R_ECX] != 0) {
        raise_exception(env, EXCP0D_GPF);
    }
    helper_svm_check_intercept_param(env, SVM_EXIT_MWAIT, 0);
    env->eip += next_eip_addend;

    /* XXX: not complete but not completely erroneous */
    CPUState *cpu = ENV_GET_CPU(env);
    if (cpu->cpu_index != 0 || QTAILQ_NEXT(cpu, node) != NULL) {
        /* more than one CPU: do not sleep because another CPU may
           wake this one */
    } else {
        do_hlt(env);
    }
}

void helper_debug(CPUX86State *env)
{
    env->exception_index = EXCP_DEBUG;
    cpu_loop_exit(env);
}