V9/sys/sun3/reg.h

/*	@(#)reg.h 1.1 86/02/03 SMI	*/

/*
 * Copyright (c) 1985 by Sun Microsystems, Inc.
 */

#ifndef _REG_
#define _REG_

/*
 * Location of the users' stored
 * registers relative to R0.
 * Usage is u.u_ar0[XX].
 */
#define	R0	(0)
#define	R1	(1)
#define	R2	(2)
#define	R3	(3)
#define	R4	(4)
#define	R5	(5)
#define	R6	(6)
#define	R7	(7)
#define	AR0	(8)
#define	AR1	(9)
#define	AR2	(10)
#define	AR3	(11)
#define	AR4	(12)
#define	AR5	(13)
#define	AR6	(14)
#define	AR7	(15)
#define	SP	(15)
#define	PS	(16)
#define	PC	(17)

/*
 * And now for something completely the same...
 */
#ifndef LOCORE
struct regs {	
	int	r_dreg[8];	/* data registers */
#define r_r0	r_dreg[0]	/* r0 for portability */
	int	r_areg[8];	/* address registers */
#define r_sp	r_areg[7]	/* user stack pointer */
	int	r_sr;		/* status register (actually a short) */
#define	r_ps	r_sr
	int	r_pc;		/* program counter */
};

struct stkfmt {
	int	f_stkfmt : 4;	/* stack format */
	int		 : 2;
	int	f_vector : 10;	/* vector offset */
	short	f_beibase;	/* start of bus error info (if any) */
};


/*
 * Struct for floating point registers and general state
 * for the MC68881 (the sky fpp has no user visible state).
 * If fps_flags == FPS_UNUSED, the other 68881 fields have no meaning.
 * fps_code and fps_flags are software implemented fields.
 * fps_flags is not used when set by user level programs,
 * but changing fps_code has the side effect of changing u.u_code.
 */

typedef	struct ext_fp {
	int	fp[3];
} ext_fp;		/* extended 96-bit 68881 fp registers */

struct fp_status {
	ext_fp	fps_regs[8];		/* 68881 floating point regs */
	int	fps_control;		/* 68881 control reg */
	int	fps_status;		/* 68881 status reg */
	int	fps_iaddr;		/* 68881 instruction address reg */
	int	fps_code;		/* additional word for signals */
	int	fps_flags;		/* r/o - unused, idle or busy */
};
#endif !LOCORE

/*
 * Values defined for `fps_flags'.
 */
#define	FPS_UNUSED	0		/* 68881 never used yet */
#define	FPS_IDLE	1		/* 68881 instruction completed */
#define	FPS_BUSY	2		/* 68881 instruction interrupted */

#ifndef LOCORE
/*
 * Struct for the internal state of the MC68881
 * Although the MC68881 can have a smaller maximum for
 * internal state, we allow for more to allow for expansion.
 * A fpis_vers and fpis_bufsize of zero means NULL state.
 */
#define	FPIS_BUFSIZ	192

struct fp_istate {
	unsigned char	fpis_vers;		/* version number */
	unsigned char	fpis_bufsiz;		/* size of info in fpis_buf */
	unsigned short	fpis_reserved;		/* reserved word */
	unsigned char	fpis_buf[FPIS_BUFSIZ];	/* fpp internal state buffer */
};

/*
 * Known values for fpis_bufsiz when null/idle, otherwize we have
 * to assume it's busy.  The EXT_FPS_FLAGS() macro is used to
 * convert a pointer to an fp_istate into a value to be used
 * for the user visible state found in fps_flags.  As a speed
 * optimization, this convertion is only done is required (e.g.
 * the PTRACE_GETFPREGS ptrace call or when dumping core) instead
 * of on each context switch.
 */
#define	FPIS_NULLSZ	0
#define	FPIS_IDLESZ	24

#define EXT_FPS_FLAGS(istatep) \
	((istatep)->fpis_bufsiz == FPIS_NULLSZ ? FPS_UNUSED : \
	    (istatep)->fpis_bufsiz == FPIS_IDLESZ ? FPS_IDLE : FPS_BUSY)

/* 
 * Structures for the status and data registers are defined here.
 * If fpais_context == FPA_NO_CONTEXT, the other FPA fields have
 * no meaning.  Struct fpa_istate and fpa_status are included in the
 * u area.  Struct fpa_regs is included in struct core.
 */

struct fpa_istate {
	unsigned int	fpais_context;	/* 0-31, 32 means FPA not used   */
	unsigned int	fpais_state;	/* FPA STATE register */
};

#define FPA_NO_CONTEXT	32

struct fpa_status {
	unsigned int	fpas_status[3]; /* IMASK, LOAD_PTR, IERR */
	unsigned short	fpas_opcode[4]; /* pipe instruction halves */
	unsigned int	fpas_operand[4];/* pipe data halves */
	unsigned int	fpas_mode;	/* FPA MODE3_0 register */
};

/* 
 * Since there are 64 8-byte data registers, save/restore them during
 * context switch both consumes time and occupies 512 bytes in the u area.
 * Also, there are 32 contexts supported by the fpa hardware.
 * Therefore, when we do context switch on the fpa, we don't save/restore
 * the data registers between the fpa and  the u area.  To protect
 * data registers from being overwritten, if there are already 32
 * processes using the fpa concurrently, we give an error message to
 * the 33rd process trying to use the fpa.  (Hopefully there will not
 * be this many processes using fpa concurrently.)
 */

/* 
 * There are 64 64-bit data registers. Since the data path between cpu
 * and fpa is 32 bit wide, we view FPA data registers as 128 unsigned int's.
 */
#define FPA_NLONG_WORDS		128

struct fpa_data {
	unsigned int	fpad_data[FPA_NLONG_WORDS]; /* FPA data registers */
	unsigned int	fpad_wstatus;	/* FPA WSTATUS register */
};

struct fpa_regs {
	struct	fpa_istate	fpar_istate;
        struct  fpa_status      fpar_status;
        struct  fpa_data        fpar_data;
};

#endif !LOCORE

#endif !_REG_