/* $OpenBSD: m88110_fp.S,v 1.2 2004/08/09 20:52:11 miod Exp $ */
/*
* Copyright (c) 1999 Steve Murphree, Jr.
* All rights reserved.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Christopher G. Demetriou.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
/* Floating point trouble routines */
/*
* August 1, 1999
* smurph@OpenBSD.org
*
* Additions to support MVME197 (mc88110) mmu routines.
*/
/*
* This is cheesy. I'm using the TCFP features of the mc88110
* because it was easy. It is not 100% IEEE. But it may be
* close enough. We shall see... XXXsmurph
* Err... TCFP == "Time Critical Floating Point"
*
* The only two SFU1 exceptions that can occure in TCFP mode are:
* 1) Unimplemented Floating Point Instruction
* 2) Floating Point Privilege Violation
*/
#include "assym.h"
#include <machine/trap.h>
#include <machine/asm.h>
ASENTRY(m88110_Xfp_precise)
or r29, r3, r0 /* r29 is now the E.F. */
subu r31, r31, 16
st r1, r31, 0
st r29, r31, 4
ld r2, r29, EF_FPSR * 4
ld r3, r29, EF_FPCR * 4
ld r4, r29, EF_FPECR * 4
/*
* Load into r1 the return address for the 0 handlers. Looking
* at FPECR, branch to the appropriate 0 handler. However,
* if none of the 0 bits are enabled, then a floating point
* instruction was issued with the floating point unit disabled. This
* will cause an unimplemented opcode 0.
*/
bb0 6,r4, 2f /* branch to m88110_FPunimp if bit set */
br _ASM_LABEL(m88110_FPuimp)
2: bb0 5,r4, 3f /* branch to m88110_FPpriviol if bit set */
br _ASM_LABEL(m88110_FPpriviol)
3:
or.u r4, r4, 0xffff
ASLOCAL(m88110_FPuimp)
subu r31,r31,16 /* allocate stack */
st r1,r31,4 /* save return address */
st r3,r31,0 /* save exception frame */
or r2,r0,T_FPEPFLT /* load trap type */
bsr.n _C_LABEL(m88110_trap) /* trap */
or r3, r29, r0
ld r1,r31,4 /* recover return address */
jmp.n r1
addu r31,r31,16 /* deallocate stack */
ASLOCAL(m88110_FPpriviol)
subu r31,r31,16 /* allocate stack */
st r1,r31,4 /* save return address */
st r3,r31,0 /* save exception frame */
or r2,r0,T_PRIVINFLT /* load trap type */
bsr.n _C_LABEL(m88110_trap) /* trap */
or r3, r29, r0
ld r1,r31,4 /* recover return address */
jmp.n r1
addu r31,r31,16 /* deallocate stack */
ENTRY(set_tcfp)
or.u r2, r0, hi16(0x200000)
or r2, r2, lo16(0x200000)
jmp.n r1
fstcr r2, fcr0