/* SPDX-License-Identifier: GPL-2.0 */
/* Written 2000 by Andi Kleen */
#ifndef _ASM_X86_DESC_DEFS_H
#define _ASM_X86_DESC_DEFS_H

/*
 * Segment descriptor structure definitions, usable from both x86_64 and i386
 * archs.
 */

/*
 * Low-level interface mapping flags/field names to bits
 */

/* Flags for _DESC_S (non-system) descriptors */
#define _DESC_ACCESSED          0x0001
#define _DESC_DATA_WRITABLE     0x0002
#define _DESC_CODE_READABLE     0x0002
#define _DESC_DATA_EXPAND_DOWN  0x0004
#define _DESC_CODE_CONFORMING   0x0004
#define _DESC_CODE_EXECUTABLE   0x0008

/* Common flags */
#define _DESC_S                 0x0010
#define _DESC_DPL(dpl)          ((dpl) << 5)
#define _DESC_PRESENT           0x0080

#define _DESC_LONG_CODE         0x2000
#define _DESC_DB                0x4000
#define _DESC_GRANULARITY_4K    0x8000

/* System descriptors have a numeric "type" field instead of flags */
#define _DESC_SYSTEM(code)      (code)

/*
 * High-level interface mapping intended usage to low-level combinations
 * of flags
 */

#define _DESC_DATA              (_DESC_S | _DESC_PRESENT | _DESC_ACCESSED | \
                                 _DESC_DATA_WRITABLE)
#define _DESC_CODE              (_DESC_S | _DESC_PRESENT | _DESC_ACCESSED | \
                                 _DESC_CODE_READABLE | _DESC_CODE_EXECUTABLE)

#define DESC_DATA16             (_DESC_DATA)
#define DESC_CODE16             (_DESC_CODE)

#define DESC_DATA32             (_DESC_DATA | _DESC_GRANULARITY_4K | _DESC_DB)
#define DESC_DATA32_BIOS        (_DESC_DATA | _DESC_DB)

#define DESC_CODE32             (_DESC_CODE | _DESC_GRANULARITY_4K | _DESC_DB)
#define DESC_CODE32_BIOS        (_DESC_CODE | _DESC_DB)

#define DESC_TSS32              (_DESC_SYSTEM(9) | _DESC_PRESENT)

#define DESC_DATA64             (_DESC_DATA | _DESC_GRANULARITY_4K | _DESC_DB)
#define DESC_CODE64             (_DESC_CODE | _DESC_GRANULARITY_4K | _DESC_LONG_CODE)

#define DESC_USER               (_DESC_DPL(3))

#ifndef __ASSEMBLER__

#include <linux/types.h>

/* 8 byte segment descriptor */
struct desc_struct {
        u16     limit0;
        u16     base0;
        u16     base1: 8, type: 4, s: 1, dpl: 2, p: 1;
        u16     limit1: 4, avl: 1, l: 1, d: 1, g: 1, base2: 8;
} __attribute__((packed));

#define GDT_ENTRY_INIT(flags, base, limit)                      \
        {                                                       \
                .limit0         = ((limit) >>  0) & 0xFFFF,     \
                .limit1         = ((limit) >> 16) & 0x000F,     \
                .base0          = ((base)  >>  0) & 0xFFFF,     \
                .base1          = ((base)  >> 16) & 0x00FF,     \
                .base2          = ((base)  >> 24) & 0x00FF,     \
                .type           = ((flags) >>  0) & 0x000F,     \
                .s              = ((flags) >>  4) & 0x0001,     \
                .dpl            = ((flags) >>  5) & 0x0003,     \
                .p              = ((flags) >>  7) & 0x0001,     \
                .avl            = ((flags) >> 12) & 0x0001,     \
                .l              = ((flags) >> 13) & 0x0001,     \
                .d              = ((flags) >> 14) & 0x0001,     \
                .g              = ((flags) >> 15) & 0x0001,     \
        }

enum {
        GATE_INTERRUPT = 0xE,
        GATE_TRAP = 0xF,
        GATE_CALL = 0xC,
        GATE_TASK = 0x5,
};

enum {
        DESC_TSS = 0x9,
        DESC_LDT = 0x2,
        DESCTYPE_S = 0x10,      /* !system */
};

/* LDT or TSS descriptor in the GDT. */
struct ldttss_desc {
        u16     limit0;
        u16     base0;

        u16     base1 : 8, type : 5, dpl : 2, p : 1;
        u16     limit1 : 4, zero0 : 3, g : 1, base2 : 8;
#ifdef CONFIG_X86_64
        u32     base3;
        u32     zero1;
#endif
} __attribute__((packed));

typedef struct ldttss_desc ldt_desc;
typedef struct ldttss_desc tss_desc;

struct idt_bits {
        u16             ist     : 3,
                        zero    : 5,
                        type    : 5,
                        dpl     : 2,
                        p       : 1;
} __attribute__((packed));

struct idt_data {
        unsigned int    vector;
        unsigned int    segment;
        struct idt_bits bits;
        const void      *addr;
};

struct gate_struct {
        u16             offset_low;
        u16             segment;
        struct idt_bits bits;
        u16             offset_middle;
#ifdef CONFIG_X86_64
        u32             offset_high;
        u32             reserved;
#endif
} __attribute__((packed));

typedef struct gate_struct gate_desc;

#ifndef _SETUP
static inline unsigned long gate_offset(const gate_desc *g)
{
#ifdef CONFIG_X86_64
        return g->offset_low | ((unsigned long)g->offset_middle << 16) |
                ((unsigned long) g->offset_high << 32);
#else
        return g->offset_low | ((unsigned long)g->offset_middle << 16);
#endif
}

static inline unsigned long gate_segment(const gate_desc *g)
{
        return g->segment;
}
#endif

struct desc_ptr {
        unsigned short size;
        unsigned long address;
} __attribute__((packed)) ;

#endif /* !__ASSEMBLER__ */

/* Boot IDT definitions */
#define BOOT_IDT_ENTRIES        32

/* Access rights as returned by LAR */
#define AR_TYPE_RODATA          (0 * (1 << 9))
#define AR_TYPE_RWDATA          (1 * (1 << 9))
#define AR_TYPE_RODATA_EXPDOWN  (2 * (1 << 9))
#define AR_TYPE_RWDATA_EXPDOWN  (3 * (1 << 9))
#define AR_TYPE_XOCODE          (4 * (1 << 9))
#define AR_TYPE_XRCODE          (5 * (1 << 9))
#define AR_TYPE_XOCODE_CONF     (6 * (1 << 9))
#define AR_TYPE_XRCODE_CONF     (7 * (1 << 9))
#define AR_TYPE_MASK            (7 * (1 << 9))

#define AR_DPL0                 (0 * (1 << 13))
#define AR_DPL3                 (3 * (1 << 13))
#define AR_DPL_MASK             (3 * (1 << 13))

#define AR_A                    (1 << 8)   /* "Accessed" */
#define AR_S                    (1 << 12)  /* If clear, "System" segment */
#define AR_P                    (1 << 15)  /* "Present" */
#define AR_AVL                  (1 << 20)  /* "AVaiLable" (no HW effect) */
#define AR_L                    (1 << 21)  /* "Long mode" for code segments */
#define AR_DB                   (1 << 22)  /* D/B, effect depends on type */
#define AR_G                    (1 << 23)  /* "Granularity" (limit in pages) */

#endif /* _ASM_X86_DESC_DEFS_H */