linux/arch/mips/include/asm/fpu_emulator.h
Ralf Baechle ba3049ed40 MIPS: Switch FPU emulator trap to BREAK instruction.
Arguably using the address error handler has always been ugly.  But with
processors that handle unaligned loads and stores in hardware the
current mechanism ceases to work so switch it to a BREAK instruction and
allocate break code 514 to the FPU emulator.

Yoichi Yuasa provided a build fix for CONFIG_BUG=n.

Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp>
2008-10-30 14:44:34 +00:00

55 lines
1.8 KiB
C

/*
* This program is free software; you can distribute it and/or modify it
* under the terms of the GNU General Public License (Version 2) as
* published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
*
* Further private data for which no space exists in mips_fpu_struct.
* This should be subsumed into the mips_fpu_struct structure as
* defined in processor.h as soon as the absurd wired absolute assembler
* offsets become dynamic at compile time.
*
* Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
* Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
*/
#ifndef _ASM_FPU_EMULATOR_H
#define _ASM_FPU_EMULATOR_H
#include <asm/break.h>
#include <asm/inst.h>
struct mips_fpu_emulator_stats {
unsigned int emulated;
unsigned int loads;
unsigned int stores;
unsigned int cp1ops;
unsigned int cp1xops;
unsigned int errors;
};
extern struct mips_fpu_emulator_stats fpuemustats;
extern int mips_dsemul(struct pt_regs *regs, mips_instruction ir,
unsigned long cpc);
extern int do_dsemulret(struct pt_regs *xcp);
/*
* Instruction inserted following the badinst to further tag the sequence
*/
#define BD_COOKIE 0x0000bd36 /* tne $0, $0 with baggage */
/*
* Break instruction with special math emu break code set
*/
#define BREAK_MATH (0x0000000d | (BRK_MEMU << 16))
#endif /* _ASM_FPU_EMULATOR_H */