/* fppALib.s - floating-point coprocessor support assembly language routines *//* Copyright 1984-2000 Wind River Systems, Inc. */	.data	.globl	_copyright_wind_river	.long	_copyright_wind_river/*modification history--------------------01b,26nov01,dee  remove reference to _DIAB_TOOL01a,17mar00,dra  Created from T1.0.1 ColdFire and T2 m68k ports.*//*DESCRIPTIONThis library contains routines to support the MC68881/MC68882 floating-pointcoprocessor.  The routines fppSave() and fppRestore() save and restore all thetask floating-point context information, which consists of the eight extendeddouble precision registers and three control registers.  Higher-level accessmechanisms are found in fppLib.SEE ALSO: fppLib, MC68881/MC68882 Floating-Point Coprocessor User's Manual*/#define _ASMLANGUAGE#include "vxWorks.h"#include "fppLib.h"#include "asm.h"/* The following flag controls the assembly of the fpp instructions. *   If TRUE, the fpp instructions are assembled (many assemblers can't handle). *   If FALSE, hand-coded machine code equivalents are assembled. */#define FPP_ASSEM	FALSE	.text	.even	/* internals */	.globl _fppSave	.globl _fppRestore	.globl _fppProbeSup	.globl _fppProbeTrap	.globl _fppDtoDx	.globl _fppDxtoD	.datafppNullStateFrame:	.long  0x00000000fppCPVersion:	.byte  0xff	.text	.even/********************************************************************************* fppSave - save the floating-pointing coprocessor context** This routine saves the floating-point coprocessor context.* The context saved is:**	- registers fpcr, fpsr, and fpiar*	- registers f0 - f7*	- internal state frame** If the internal state frame is null, the other registers are not saved.** FIXME: Coldfire FP ???** RETURNS: N/A** SEE ALSO: fppRestore(), MC68881/MC68882 Floating-Point Coprocessor* User's Manual* void fppSave*    (*    FP_CONTEXT *  pFpContext  /* where to save context **    )*/_fppSave:	link	a6,#0	movel	a6@(ARG1),a0			/* where to save registers */so_null:	unlk	a6	rts/********************************************************************************* fppRestore - restore the floating-point coprocessor context** This routine restores the floating-point coprocessor context.* The context restored is:**	- registers fpcr, fpsr, and fpiar*	- registers f0 - f7*	- internal state frame** If the internal state frame is null, the other registers are not restored.** FIXME: Coldfire FP ???** RETURNS: N/A** SEE ALSO: fppSave(), MC68881/MC68882 Floating-Point Coprocessor User's Manual* void fppRestore*    (*    FP_CONTEXT *  pFpContext  /* from where to restore context **    )*/_fppRestore:	link	a6,#0	unlk	a6	rts/********************************************************************************* fppDtoDx - convert double to extended double precision** The MC68881 uses a special extended double precision format* (12 bytes as opposed to 8 bytes) for internal operations.* The routines fppSave and fppRestore must preserve this precision.** NOMANUAL* void fppDtoDx (pDx, pDouble)*     DOUBLEX *pDx;	 /* where to save result    **     double *pDouble;	 /* ptr to value to convert **/_fppDtoDx:	link	a6,#0	unlk	a6	rts/********************************************************************************* fppDxtoD - convert extended double precisoion to double** The MC68881 uses a special extended double precision format* (12 bytes as opposed to 8 bytes) for internal operations.* The routines fppSave and fppRestore must preserve this precision.** NOMANUAL* void fppDxtoD (pDouble, pDx)*     double *pDouble;		/* where to save result    **     DOUBLEX *pDx;		/* ptr to value to convert **/_fppDxtoD:	link	a6,#0	unlk	a6	rts/********************************************************************************* fppProbeSup - fppProbe support routine** This routine executes some coprocessor instruction which will cause a* bus error if a coprocessor is not present.  A handler, viz. fppProbeTrap,* should be installed at that vector.  If the coprocessor is present this* routine returns OK.** SEE ALSO: MC68881/MC68882 User's Manual, page 5-15** NOMANUAL* STATUS fppProbeSup ()*/_fppProbeSup:	link	a6,#0	clrl	d0		/* set status to OK */	nop#if FPP_ASSEM	fmovecr	#0,fp0		/* 040 unimplemented instruction */#else	.word	0xf200,0x5c00	/* fmovecr #0,fp0 */#endif	nopfppProbeSupEnd:	unlk    a6	rts/****************************************************************************** fppProbeTrap - fppProbe support routine** This entry point is momentarily attached to the coprocessor illegal opcode* error exception vector.  Usually it simply sets d0 to ERROR to indicate that* the illegal opcode error did occur, and returns from the interrupt.  The* 68040/68060 version, however, stores the coprocessor version number for pseudo* frame construction in fppSave, and leaves d0 with the value of OK.** NOMANUAL*/_fppProbeTrap:			/* coprocessor illegal error trap */	movel	#fppProbeSupEnd,d0	/* change PC to bail out */	movel	d0,a7@(4)	movel	#-1,d0			/* set status to ERROR */	rte				/* return to fppProbeSupEnd */