/*      $NetBSD: cpu.h,v 1.140 2025/04/24 01:50:39 riastradh Exp $      */

/*
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * William Jolitz.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      @(#)cpu.h       5.4 (Berkeley) 5/9/91
 */

#ifndef _X86_CPU_H_
#define _X86_CPU_H_

#if defined(_KERNEL) || defined(_STANDALONE)
#include <sys/types.h>
#else
#include <stdint.h>
#include <stdbool.h>
#endif /* _KERNEL || _STANDALONE */

#if defined(_KERNEL) || defined(_KMEMUSER)
#if defined(_KERNEL_OPT)
#include "opt_xen.h"
#include "opt_svs.h"
#endif

/*
 * Definitions unique to x86 cpu support.
 */
#include <machine/frame.h>
#include <machine/pte.h>
#include <machine/segments.h>
#include <machine/tss.h>
#include <machine/intrdefs.h>

#include <x86/cacheinfo.h>

#include <sys/cpu_data.h>
#include <sys/evcnt.h>
#include <sys/device_if.h> /* for device_t */

#ifdef SVS
#include <sys/mutex.h>
#endif

#ifdef XEN
#include <xen/include/public/xen.h>
#include <xen/include/public/event_channel.h>
#include <sys/mutex.h>
#endif /* XEN */

struct intrsource;
struct pmap;
struct kcpuset;

#ifdef __x86_64__
#define i386tss x86_64_tss
#endif

#define NIOPORTS        1024            /* # of ports we allow to be mapped */
#define IOMAPSIZE       (NIOPORTS / 8)  /* I/O bitmap size in bytes */

struct cpu_tss {
#ifdef i386
        struct i386tss dblflt_tss;
        struct i386tss ddbipi_tss;
#endif
        struct i386tss tss;
        uint8_t iomap[IOMAPSIZE];
} __packed;

/*
 * Arguments to hardclock, softclock and statclock
 * encapsulate the previous machine state in an opaque
 * clockframe; for now, use generic intrframe.
 */
struct clockframe {
        struct intrframe cf_if;
};

struct idt_vec {
        void *iv_idt;
        void *iv_idt_pentium;
        char iv_allocmap[NIDT];
};

/*
 * a bunch of this belongs in cpuvar.h; move it later..
 */

struct cpu_info {
        struct cpu_data ci_data;        /* MI per-cpu data */
        device_t ci_dev;                /* pointer to our device */
        struct cpu_info *ci_self;       /* self-pointer */

        /*
         * Private members.
         */
        struct pmap *ci_pmap;           /* current pmap */
        int ci_want_pmapload;           /* pmap_load() is needed */
        volatile int ci_tlbstate;       /* one of TLBSTATE_ states. see below */
#define TLBSTATE_VALID  0       /* all user tlbs are valid */
#define TLBSTATE_LAZY   1       /* tlbs are valid but won't be kept uptodate */
#define TLBSTATE_STALE  2       /* we might have stale user tlbs */
        int ci_curldt;          /* current LDT descriptor */
        int ci_nintrhand;       /* number of H/W interrupt handlers */
        uint64_t ci_scratch;
        uintptr_t ci_pmap_data[128 / sizeof(uintptr_t)];
        struct kcpuset *ci_tlb_cpuset;
        struct idt_vec ci_idtvec;

        int ci_kfpu_spl;

        struct intrsource *ci_isources[MAX_INTR_SOURCES];
        
        volatile int    ci_mtx_count;   /* Negative count of spin mutexes */
        volatile int    ci_mtx_oldspl;  /* Old SPL at this ci_idepth */

        /* The following must be aligned for cmpxchg8b. */
        union {
                uint64_t        ci_istate;
                struct {
                        uint64_t        ci_ipending:56;
                        uint64_t        ci_ilevel:8;
                };
        } __aligned(8);
        uint64_t        ci_imasked;

        int             ci_idepth;
        void *          ci_intrstack;
        uint64_t        ci_imask[NIPL];
        uint64_t        ci_iunmask[NIPL];

        uint32_t        ci_signature;   /* X86 cpuid type (cpuid.1.%eax) */
        uint32_t        ci_vendor[4];   /* vendor string */
        uint32_t        ci_max_cpuid;   /* cpuid.0:%eax */
        uint32_t        ci_max_ext_cpuid; /* cpuid.80000000:%eax */
        volatile uint32_t       ci_lapic_counter;

        uint32_t        ci_feat_val[8]; /* X86 CPUID feature bits */
                        /* [0] basic features cpuid.1:%edx
                         * [1] basic features cpuid.1:%ecx (CPUID2_xxx bits)
                         * [2] extended features cpuid:80000001:%edx
                         * [3] extended features cpuid:80000001:%ecx
                         * [4] VIA padlock features
                         * [5] structured extended features cpuid.7:%ebx
                         * [6] structured extended features cpuid.7:%ecx
                         * [7] structured extended features cpuid.7:%edx
                         */
        
        const struct cpu_functions *ci_func;  /* start/stop functions */
        struct trapframe *ci_ddb_regs;

        u_int ci_cflush_lsize;  /* CLFLUSH insn line size */
        struct x86_cache_info ci_cinfo[CAI_COUNT];

        device_t        ci_frequency;   /* Frequency scaling technology */
        device_t        ci_padlock;     /* VIA PadLock private storage */
        device_t        ci_temperature; /* Intel coretemp(4) or equivalent */
        device_t        ci_vm;          /* Virtual machine guest driver */

        /*
         * Segmentation-related data.
         */
        union descriptor *ci_gdt;
        struct cpu_tss  *ci_tss;        /* Per-cpu TSSes; shared among LWPs */
        int ci_tss_sel;                 /* TSS selector of this cpu */

        /*
         * The following two are actually region_descriptors,
         * but that would pollute the namespace.
         */
        uintptr_t       ci_suspend_gdt;
        uint16_t        ci_suspend_gdt_padding;
        uintptr_t       ci_suspend_idt;
        uint16_t        ci_suspend_idt_padding;

        uint16_t        ci_suspend_tr;
        uint16_t        ci_suspend_ldt;
        uintptr_t       ci_suspend_fs;
        uintptr_t       ci_suspend_gs;
        uintptr_t       ci_suspend_kgs;
        uintptr_t       ci_suspend_efer;
        uintptr_t       ci_suspend_reg[12];
        uintptr_t       ci_suspend_cr0;
        uintptr_t       ci_suspend_cr2;
        uintptr_t       ci_suspend_cr3;
        uintptr_t       ci_suspend_cr4;
        uintptr_t       ci_suspend_cr8;

        /*
         * The following must be in their own cache line, as they are
         * stored to regularly by remote CPUs; when they were mixed with
         * other fields we observed frequent cache misses.
         */
        int             ci_want_resched __aligned(64);
        uint32_t        ci_ipis; /* interprocessor interrupts pending */

        /*
         * These are largely static, and will be frequently fetched by other
         * CPUs.  For that reason they get their own cache line, too.
         */
        uint32_t        ci_flags __aligned(64);/* general flags */
        uint32_t        ci_acpiid;      /* our ACPI/MADT ID */
        uint32_t        ci_initapicid;  /* our initial APIC ID */
        uint32_t        ci_vcpuid;      /* our CPU id for hypervisor */
        cpuid_t         ci_cpuid;       /* our CPU ID */
        struct cpu_info *ci_next;       /* next cpu */

        /*
         * This is stored frequently, and is fetched by remote CPUs.
         */
        struct lwp      *ci_curlwp __aligned(64);/* general flags */
        struct lwp      *ci_onproc;     /* current user LWP / kthread */

        /* Here ends the cachline-aligned sections. */
        int             ci_padout __aligned(64);

#ifndef __HAVE_DIRECT_MAP
#define VPAGE_SRC 0
#define VPAGE_DST 1
#define VPAGE_ZER 2
#define VPAGE_PTP 3
#define VPAGE_MAX 4
        vaddr_t         vpage[VPAGE_MAX];
        pt_entry_t      *vpage_pte[VPAGE_MAX];
#endif

#ifdef PAE
        uint32_t        ci_pae_l3_pdirpa; /* PA of L3 PD */
        pd_entry_t *    ci_pae_l3_pdir; /* VA pointer to L3 PD */
#endif

#ifdef SVS
        pd_entry_t *    ci_svs_updir;
        paddr_t         ci_svs_updirpa;
        int             ci_svs_ldt_sel;
        kmutex_t        ci_svs_mtx;
        pd_entry_t *    ci_svs_rsp0_pte;
        vaddr_t         ci_svs_rsp0;
        vaddr_t         ci_svs_ursp0;
        vaddr_t         ci_svs_krsp0;
        vaddr_t         ci_svs_utls;
#endif

#ifndef XENPV
        struct evcnt ci_ipi_events[X86_NIPI];
#else
        struct evcnt ci_ipi_events[XEN_NIPIS];
#endif
#ifdef XEN
        volatile struct vcpu_info *ci_vcpu; /* for XEN */
        u_long ci_evtmask[NR_EVENT_CHANNELS]; /* events allowed on this CPU */
        evtchn_port_t ci_ipi_evtchn;
#if defined(XENPV)
#if defined(PAE) || defined(__x86_64__)
        /* Currently active user PGD (can't use rcr3() with Xen) */
        pd_entry_t *    ci_kpm_pdir;    /* per-cpu PMD (va) */
        paddr_t         ci_kpm_pdirpa;  /* per-cpu PMD (pa) */
        kmutex_t        ci_kpm_mtx;
#endif /* defined(PAE) || defined(__x86_64__) */

#if defined(__x86_64__)
        /* per-cpu version of normal_pdes */
        pd_entry_t *    ci_normal_pdes[3]; /* Ok to hardcode. only for x86_64 && XENPV */
        paddr_t         ci_xen_current_user_pgd;
#endif  /* defined(__x86_64__) */

        size_t          ci_xpq_idx;
#endif /* XENPV */

        /* Xen raw system time at which we last ran hardclock.  */
        uint64_t        ci_xen_hardclock_systime_ns;

        /*
         * Last TSC-adjusted local Xen system time we observed.  Used
         * to detect whether the Xen clock has gone backwards.
         */
        uint64_t        ci_xen_last_systime_ns;

        /*
         * Distance in nanoseconds from the local view of system time
         * to the global view of system time, if the local time is
         * behind the global time.
         */
        uint64_t        ci_xen_systime_ns_skew;

        /*
         * Clockframe for timer interrupt handler.
         * Saved at entry via event callback.
         */
        vaddr_t ci_xen_clockf_pc; /* RIP at last event interrupt */
        bool ci_xen_clockf_usermode; /* Was the guest in usermode ? */

        /* Event counters for various pathologies that might happen.  */
        struct evcnt    ci_xen_cpu_tsc_backwards_evcnt;
        struct evcnt    ci_xen_tsc_delta_negative_evcnt;
        struct evcnt    ci_xen_raw_systime_wraparound_evcnt;
        struct evcnt    ci_xen_raw_systime_backwards_evcnt;
        struct evcnt    ci_xen_systime_backwards_hardclock_evcnt;
        struct evcnt    ci_xen_missed_hardclock_evcnt;
        struct evcnt    ci_xen_timecounter_backwards_evcnt;
        struct evcnt    ci_xen_timecounter_jump_evcnt;
#endif  /* XEN */

#if defined(GPROF) && defined(MULTIPROCESSOR)
        struct gmonparam *ci_gmon;      /* MI per-cpu GPROF */
#endif
};

#if defined(XEN) && !defined(XENPV)
        __CTASSERT(XEN_NIPIS <= X86_NIPI);
#endif

/*
 * Macros to handle (some) trapframe registers for common x86 code.
 */
#ifdef __x86_64__
#define X86_TF_RAX(tf)          tf->tf_rax
#define X86_TF_RDX(tf)          tf->tf_rdx
#define X86_TF_RSP(tf)          tf->tf_rsp
#define X86_TF_RIP(tf)          tf->tf_rip
#define X86_TF_RFLAGS(tf)       tf->tf_rflags
#else
#define X86_TF_RAX(tf)          tf->tf_eax
#define X86_TF_RDX(tf)          tf->tf_edx
#define X86_TF_RSP(tf)          tf->tf_esp
#define X86_TF_RIP(tf)          tf->tf_eip
#define X86_TF_RFLAGS(tf)       tf->tf_eflags
#endif

/*
 * Processor flag notes: The "primary" CPU has certain MI-defined
 * roles (mostly relating to hardclock handling); we distinguish
 * between the processor which booted us, and the processor currently
 * holding the "primary" role just to give us the flexibility later to
 * change primaries should we be sufficiently twisted.
 */

#define CPUF_BSP        0x0001          /* CPU is the original BSP */
#define CPUF_AP         0x0002          /* CPU is an AP */
#define CPUF_SP         0x0004          /* CPU is only processor */
#define CPUF_PRIMARY    0x0008          /* CPU is active primary processor */

#define CPUF_SYNCTSC    0x0800          /* Synchronize TSC */
#define CPUF_PRESENT    0x1000          /* CPU is present */
#define CPUF_RUNNING    0x2000          /* CPU is running */
#define CPUF_PAUSE      0x4000          /* CPU is paused in DDB */
#define CPUF_GO         0x8000          /* CPU should start running */

#endif /* _KERNEL || __KMEMUSER */

#ifdef _KERNEL
/*
 * We statically allocate the CPU info for the primary CPU (or,
 * the only CPU on uniprocessors), and the primary CPU is the
 * first CPU on the CPU info list.
 */
extern struct cpu_info cpu_info_primary;
extern struct cpu_info *cpu_info_list;

#define CPU_INFO_ITERATOR               int __unused
#define CPU_INFO_FOREACH(cii, ci)       ci = cpu_info_list; \
                                        ci != NULL; ci = ci->ci_next

#define CPU_STARTUP(_ci, _target)       ((_ci)->ci_func->start(_ci, _target))
#define CPU_STOP(_ci)                   ((_ci)->ci_func->stop(_ci))
#define CPU_START_CLEANUP(_ci)          ((_ci)->ci_func->cleanup(_ci))

#if !defined(__GNUC__) || defined(_MODULE)
/* For non-GCC and modules */
struct cpu_info *x86_curcpu(void);
# ifdef __GNUC__
lwp_t   *x86_curlwp(void) __attribute__ ((const));
# else
lwp_t   *x86_curlwp(void);
# endif
#endif

#define cpu_number()            (cpu_index(curcpu()))

#define CPU_IS_PRIMARY(ci)      ((ci)->ci_flags & CPUF_PRIMARY)

#define aston(l)                ((l)->l_md.md_astpending = 1)

void cpu_boot_secondary_processors(void);
void cpu_init_idle_lwps(void);
void cpu_init_msrs(struct cpu_info *, bool);
void cpu_load_pmap(struct pmap *, struct pmap *);
void cpu_broadcast_halt(void);
void cpu_kick(struct cpu_info *);

void cpu_pcpuarea_init(struct cpu_info *);
void cpu_svs_init(struct cpu_info *);
void cpu_speculation_init(struct cpu_info *);

#define curcpu()                x86_curcpu()
#define curlwp                  x86_curlwp()
#define curpcb                  ((struct pcb *)lwp_getpcb(curlwp))

/*
 * Give a profiling tick to the current process when the user profiling
 * buffer pages are invalid.  On the i386, request an ast to send us
 * through trap(), marking the proc as needing a profiling tick.
 */
extern void     cpu_need_proftick(struct lwp *l);

/*
 * Notify the LWP l that it has a signal pending, process as soon as
 * possible.
 */
extern void     cpu_signotify(struct lwp *);

/*
 * We need a machine-independent name for this.
 */
extern void (*delay_func)(unsigned int);
struct timeval;

#ifndef __HIDE_DELAY
#define DELAY(x)                (*delay_func)(x)
#define delay(x)                (*delay_func)(x)
#endif

extern int biosbasemem;
extern int biosextmem;
extern int cputype;
extern int cpuid_level;
extern int cpu_class;
extern char cpu_brand_string[];
extern int use_pae;

#ifdef __i386__
#define i386_fpu_present        1
int npx586bug1(int, int);
extern int i386_fpu_fdivbug;
extern int i386_use_fxsave;
extern int i386_has_sse;
extern int i386_has_sse2;
#else
#define i386_fpu_present        1
#define i386_fpu_fdivbug        0
#define i386_use_fxsave         1
#define i386_has_sse            1
#define i386_has_sse2           1
#endif

extern int x86_fpu_save;
#define FPU_SAVE_FSAVE          0
#define FPU_SAVE_FXSAVE         1
#define FPU_SAVE_XSAVE          2
#define FPU_SAVE_XSAVEOPT       3
extern unsigned int x86_fpu_save_size;
extern uint64_t x86_xsave_features;
extern size_t x86_xsave_offsets[];
extern size_t x86_xsave_sizes[];
extern uint32_t x86_fpu_mxcsr_mask;
bool x86_fpu_save_separate_p(void);

extern void (*x86_cpu_idle)(void);
#define cpu_idle() (*x86_cpu_idle)()

/* machdep.c */
#ifdef i386
void    cpu_set_tss_gates(struct cpu_info *);
#endif
void    cpu_reset(void);

/* longrun.c */
u_int   tmx86_get_longrun_mode(void);
void    tmx86_get_longrun_status(u_int *, u_int *, u_int *);
void    tmx86_init_longrun(void);

/* identcpu.c */
void    cpu_probe(struct cpu_info *);
void    cpu_identify(struct cpu_info *);
void    identify_hypervisor(void);

/* identcpu_subr.c */
uint64_t cpu_tsc_freq_cpuid(struct cpu_info *);
void    cpu_dcp_cacheinfo(struct cpu_info *, uint32_t);

typedef enum vm_guest {
        VM_GUEST_NO = 0,
        VM_GUEST_VM,
        VM_GUEST_XENPV,
        VM_GUEST_XENPVH,
        VM_GUEST_XENHVM,
        VM_GUEST_XENPVHVM,
        VM_GUEST_HV,
        VM_GUEST_VMWARE,
        VM_GUEST_KVM,
        VM_GUEST_VIRTUALBOX,
        VM_GUEST_GENPVH,
        VM_GUEST_NVMM,
        VM_LAST
} vm_guest_t;
extern vm_guest_t vm_guest;

static __inline bool __unused
vm_guest_is_xenpv(void)
{
        switch(vm_guest) {
        case VM_GUEST_XENPV:
        case VM_GUEST_XENPVH:
        case VM_GUEST_XENPVHVM:
                return true;
        default:
                return false;
        }
}

static __inline bool __unused
vm_guest_is_xenpvh_or_pvhvm(void)
{
        switch(vm_guest) {
        case VM_GUEST_XENPVH:
        case VM_GUEST_XENPVHVM:
                return true;
        default:
                return false;
        }
}

static __inline bool __unused
vm_guest_is_pvh(void)
{
        switch(vm_guest) {
        case VM_GUEST_XENPVH:
        case VM_GUEST_GENPVH:
                return true;
        default:
                return false;
        }
}

/* cpu_topology.c */
void    x86_cpu_topology(struct cpu_info *);

/* locore.s */
struct region_descriptor;
void    lgdt(struct region_descriptor *);
#ifdef XENPV
void    lgdt_finish(void);
#endif

struct pcb;
void    savectx(struct pcb *);
void    lwp_trampoline(void);
#ifdef XEN
void    xen_startrtclock(void);
void    xen_delay(unsigned int);
void    xen_initclocks(void);
void    xen_cpu_initclocks(void);
void    xen_suspendclocks(struct cpu_info *);
void    xen_resumeclocks(struct cpu_info *);
#endif /* XEN */
/* clock.c */
void    initrtclock(u_long);
void    startrtclock(void);
void    i8254_delay(unsigned int);
void    i8254_microtime(struct timeval *);
void    i8254_initclocks(void);
unsigned int gettick(void);
extern void (*x86_delay)(unsigned int);

/* cpu.c */
void    cpu_probe_features(struct cpu_info *);
int     x86_cpu_is_lcall(const void *);

/* vm_machdep.c */
void    cpu_proc_fork(struct proc *, struct proc *);
paddr_t kvtop(void *);

/* isa_machdep.c */
void    isa_defaultirq(void);
int     isa_nmi(void);

/* consinit.c */
void kgdb_port_init(void);

/* bus_machdep.c */
void x86_bus_space_init(void);
void x86_bus_space_mallocok(void);

#endif /* _KERNEL */

#if defined(_KERNEL) || defined(_KMEMUSER)
#include <machine/psl.h>        /* Must be after struct cpu_info declaration */
#endif /* _KERNEL || __KMEMUSER */

/*
 * CTL_MACHDEP definitions.
 */
#define CPU_CONSDEV             1       /* dev_t: console terminal device */
#define CPU_BIOSBASEMEM         2       /* int: bios-reported base mem (K) */
#define CPU_BIOSEXTMEM          3       /* int: bios-reported ext. mem (K) */
/*      CPU_NKPDE               4       obsolete: int: number of kernel PDEs */
#define CPU_BOOTED_KERNEL       5       /* string: booted kernel name */
#define CPU_DISKINFO            6       /* struct disklist *:
                                         * disk geometry information */
#define CPU_FPU_PRESENT         7       /* int: FPU is present */
#define CPU_OSFXSR              8       /* int: OS uses FXSAVE/FXRSTOR */
#define CPU_SSE                 9       /* int: OS/CPU supports SSE */
#define CPU_SSE2                10      /* int: OS/CPU supports SSE2 */
#define CPU_TMLR_MODE           11      /* int: longrun mode
                                         * 0: minimum frequency
                                         * 1: economy
                                         * 2: performance
                                         * 3: maximum frequency
                                         */
#define CPU_TMLR_FREQUENCY      12      /* int: current frequency */
#define CPU_TMLR_VOLTAGE        13      /* int: current voltage */
#define CPU_TMLR_PERCENTAGE     14      /* int: current clock percentage */
#define CPU_FPU_SAVE            15      /* int: FPU Instructions layout
                                         * to use this, CPU_OSFXSR must be true
                                         * 0: FSAVE
                                         * 1: FXSAVE
                                         * 2: XSAVE
                                         * 3: XSAVEOPT
                                         */
#define CPU_FPU_SAVE_SIZE       16      /* int: FPU Instruction layout size */
#define CPU_XSAVE_FEATURES      17      /* quad: XSAVE features */

/*
 * Structure for CPU_DISKINFO sysctl call.
 * XXX this should be somewhere else.
 */
#define MAX_BIOSDISKS   16

struct disklist {
        int dl_nbiosdisks;                         /* number of bios disks */
        int dl_unused;
        struct biosdisk_info {
                int bi_dev;                        /* BIOS device # (0x80 ..) */
                int bi_cyl;                        /* cylinders on disk */
                int bi_head;                       /* heads per track */
                int bi_sec;                        /* sectors per track */
                uint64_t bi_lbasecs;               /* total sec. (iff ext13) */
#define BIFLAG_INVALID          0x01
#define BIFLAG_EXTINT13         0x02
                int bi_flags;
                int bi_unused;
        } dl_biosdisks[MAX_BIOSDISKS];

        int dl_nnativedisks;                       /* number of native disks */
        struct nativedisk_info {
                char ni_devname[16];               /* native device name */
                int ni_nmatches;                   /* # of matches w/ BIOS */
                int ni_biosmatches[MAX_BIOSDISKS]; /* indices in dl_biosdisks */
        } dl_nativedisks[1];                       /* actually longer */
};
#endif /* !_X86_CPU_H_ */