regs.h

/*
 * Copyright (c) 2008-2014, Pedigree Developers
 *
 * Please see the CONTRIB file in the root of the source tree for a full
 * list of contributors.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef __X86EMU_REGS_H
#define __X86EMU_REGS_H

/*---------------------- Macros and type definitions ----------------------*/

#ifdef PACK
#pragma PACK
#endif

/*
 * General EAX, EBX, ECX, EDX type registers.  Note that for
 * portability, and speed, the issue of byte swapping is not addressed
 * in the registers.  All registers are stored in the default format
 * available on the host machine.  The only critical issue is that the
 * registers should line up EXACTLY in the same manner as they do in
 * the 386.  That is:
 *
 * EAX & 0xff  === AL
 * EAX & 0xffff == AX
 *
 * etc.  The result is that alot of the calculations can then be
 * done using the native instruction set fully.
 */

#ifdef __BIG_ENDIAN__

typedef struct
{
    u32 e_reg;
} I32_reg_t;

typedef struct
{
    u16 filler0, x_reg;
} I16_reg_t;

typedef struct
{
    u8 filler0, filler1, h_reg, l_reg;
} I8_reg_t;

#else /* !__BIG_ENDIAN__ */

typedef struct
{
    u32 e_reg;
} I32_reg_t;

typedef struct
{
    u16 x_reg;
} I16_reg_t;

typedef struct
{
    u8 l_reg, h_reg;
} I8_reg_t;

#endif /* BIG_ENDIAN */

typedef union
{
    I32_reg_t I32_reg;
    I16_reg_t I16_reg;
    I8_reg_t I8_reg;
} i386_general_register;

struct i386_general_regs
{
    i386_general_register A, B, C, D;
};

typedef struct i386_general_regs Gen_reg_t;

struct i386_special_regs
{
    i386_general_register SP, BP, SI, DI, IP;
    u32 FLAGS;
};

/*
 * Segment registers here represent the 16 bit quantities
 * CS, DS, ES, SS.
 */

struct i386_segment_regs
{
    u16 CS, DS, SS, ES, FS, GS;
};

/* 8 bit registers */
#define R_AH gen.A.I8_reg.h_reg
#define R_AL gen.A.I8_reg.l_reg
#define R_BH gen.B.I8_reg.h_reg
#define R_BL gen.B.I8_reg.l_reg
#define R_CH gen.C.I8_reg.h_reg
#define R_CL gen.C.I8_reg.l_reg
#define R_DH gen.D.I8_reg.h_reg
#define R_DL gen.D.I8_reg.l_reg

/* 16 bit registers */
#define R_AX gen.A.I16_reg.x_reg
#define R_BX gen.B.I16_reg.x_reg
#define R_CX gen.C.I16_reg.x_reg
#define R_DX gen.D.I16_reg.x_reg

/* 32 bit extended registers */
#define R_EAX gen.A.I32_reg.e_reg
#define R_EBX gen.B.I32_reg.e_reg
#define R_ECX gen.C.I32_reg.e_reg
#define R_EDX gen.D.I32_reg.e_reg

/* special registers */
#define R_SP spc.SP.I16_reg.x_reg
#define R_BP spc.BP.I16_reg.x_reg
#define R_SI spc.SI.I16_reg.x_reg
#define R_DI spc.DI.I16_reg.x_reg
#define R_IP spc.IP.I16_reg.x_reg
#define R_FLG spc.FLAGS

/* special registers */
#define R_SP spc.SP.I16_reg.x_reg
#define R_BP spc.BP.I16_reg.x_reg
#define R_SI spc.SI.I16_reg.x_reg
#define R_DI spc.DI.I16_reg.x_reg
#define R_IP spc.IP.I16_reg.x_reg
#define R_FLG spc.FLAGS

/* special registers */
#define R_ESP spc.SP.I32_reg.e_reg
#define R_EBP spc.BP.I32_reg.e_reg
#define R_ESI spc.SI.I32_reg.e_reg
#define R_EDI spc.DI.I32_reg.e_reg
#define R_EIP spc.IP.I32_reg.e_reg
#define R_EFLG spc.FLAGS

/* segment registers */
#define R_CS seg.CS
#define R_DS seg.DS
#define R_SS seg.SS
#define R_ES seg.ES
#define R_FS seg.FS
#define R_GS seg.GS

/* flag conditions   */
#define FB_CF 0x0001 /* CARRY flag  */
#define FB_PF 0x0004 /* PARITY flag */
#define FB_AF 0x0010 /* AUX  flag   */
#define FB_ZF 0x0040 /* ZERO flag   */
#define FB_SF 0x0080 /* SIGN flag   */
#define FB_TF 0x0100 /* TRAP flag   */
#define FB_IF 0x0200 /* INTERRUPT ENABLE flag */
#define FB_DF 0x0400 /* DIR flag    */
#define FB_OF 0x0800 /* OVERFLOW flag */

/* 80286 and above always have bit#1 set */
#define F_ALWAYS_ON (0x0002) /* flag bits always on */

/*
 * Define a mask for only those flag bits we will ever pass back
 * (via PUSHF)
 */
#define F_MSK \
    (FB_CF | FB_PF | FB_AF | FB_ZF | FB_SF | FB_TF | FB_IF | FB_DF | FB_OF)

/* following bits masked in to a 16bit quantity */

#define F_CF 0x0001 /* CARRY flag  */
#define F_PF 0x0004 /* PARITY flag */
#define F_AF 0x0010 /* AUX  flag   */
#define F_ZF 0x0040 /* ZERO flag   */
#define F_SF 0x0080 /* SIGN flag   */
#define F_TF 0x0100 /* TRAP flag   */
#define F_IF 0x0200 /* INTERRUPT ENABLE flag */
#define F_DF 0x0400 /* DIR flag    */
#define F_OF 0x0800 /* OVERFLOW flag */

#define TOGGLE_FLAG(flag) (M.x86.R_FLG ^= (flag))
#define SET_FLAG(flag) (M.x86.R_FLG |= (flag))
#define CLEAR_FLAG(flag) (M.x86.R_FLG &= ~(flag))
#define ACCESS_FLAG(flag) (M.x86.R_FLG & (flag))
#define CLEARALL_FLAG(m) (M.x86.R_FLG = 0)

#define CONDITIONAL_SET_FLAG(COND, FLAG) \
    if (COND)                            \
        SET_FLAG(FLAG);                  \
    else                                 \
        CLEAR_FLAG(FLAG)

#define F_PF_CALC 0x010000 /* PARITY flag has been calced    */
#define F_ZF_CALC 0x020000 /* ZERO flag has been calced      */
#define F_SF_CALC 0x040000 /* SIGN flag has been calced      */

#define F_ALL_CALC 0xff0000 /* All have been calced   */

/*
 * Emulator machine state.
 * Segment usage control.
 */
#define SYSMODE_SEG_DS_SS 0x00000001
#define SYSMODE_SEGOVR_CS 0x00000002
#define SYSMODE_SEGOVR_DS 0x00000004
#define SYSMODE_SEGOVR_ES 0x00000008
#define SYSMODE_SEGOVR_FS 0x00000010
#define SYSMODE_SEGOVR_GS 0x00000020
#define SYSMODE_SEGOVR_SS 0x00000040
#define SYSMODE_PREFIX_REPE 0x00000080
#define SYSMODE_PREFIX_REPNE 0x00000100
#define SYSMODE_PREFIX_DATA 0x00000200
#define SYSMODE_PREFIX_ADDR 0x00000400
#define SYSMODE_INTR_PENDING 0x10000000
#define SYSMODE_EXTRN_INTR 0x20000000
#define SYSMODE_HALTED 0x40000000

#define SYSMODE_SEGMASK                                          \
    (SYSMODE_SEG_DS_SS | SYSMODE_SEGOVR_CS | SYSMODE_SEGOVR_DS | \
     SYSMODE_SEGOVR_ES | SYSMODE_SEGOVR_FS | SYSMODE_SEGOVR_GS | \
     SYSMODE_SEGOVR_SS)
#define SYSMODE_CLRMASK                                          \
    (SYSMODE_SEG_DS_SS | SYSMODE_SEGOVR_CS | SYSMODE_SEGOVR_DS | \
     SYSMODE_SEGOVR_ES | SYSMODE_SEGOVR_FS | SYSMODE_SEGOVR_GS | \
     SYSMODE_SEGOVR_SS | SYSMODE_PREFIX_DATA | SYSMODE_PREFIX_ADDR)

#define INTR_SYNCH 0x1
#define INTR_ASYNCH 0x2
#define INTR_HALTED 0x4

typedef struct
{
    struct i386_general_regs gen;
    struct i386_special_regs spc;
    struct i386_segment_regs seg;
    /*
     * MODE contains information on:
     *  REPE prefix             2 bits  repe,repne
     *  SEGMENT overrides       5 bits  normal,DS,SS,CS,ES
     *  Delayed flag set        3 bits  (zero, signed, parity)
     *  reserved                6 bits
     *  interrupt #             8 bits  instruction raised interrupt
     *  BIOS video segregs      4 bits
     *  Interrupt Pending       1 bits
     *  Extern interrupt        1 bits
     *  Halted                  1 bits
     */
    u32 mode;
    volatile int intr; /* mask of pending interrupts */
    int debug;
#ifdef DEBUG
    int check;
    u16 saved_ip;
    u16 saved_cs;
    int enc_pos;
    int enc_str_pos;
    char decode_buf[32];   /* encoded byte stream  */
    char decoded_buf[256]; /* disassembled strings */
#endif
    u8 intno;
    u8 __pad[3];
} X86EMU_regs;

/****************************************************************************
REMARKS:
Structure maintaining the emulator machine state.

MEMBERS:
mem_base        - Base real mode memory for the emulator
mem_size        - Size of the real mode memory block for the emulator
private         - private data pointer
x86         - X86 registers
****************************************************************************/
typedef struct
{
    unsigned long mem_base;
    unsigned long mem_size;
    void *_private;
    X86EMU_regs x86;
} X86EMU_sysEnv;

#ifdef END_PACK
#pragma END_PACK
#endif

/*----------------------------- Global Variables --------------------------*/

#ifdef __cplusplus
extern "C" { /* Use "C" linkage when in C++ mode */
#endif

/* Global emulator machine state.
 *
 * We keep it global to avoid pointer dereferences in the code for speed.
 */

extern X86EMU_sysEnv _X86EMU_env;
#define M _X86EMU_env

/*-------------------------- Function Prototypes --------------------------*/

/* Function to log information at runtime */

void printk(const char *fmt, ...);

#ifdef __cplusplus
} /* End of "C" linkage for C++     */
#endif

#endif /* __X86EMU_REGS_H */