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/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
NetWinder Floating Point Emulator
(c) Rebel.com, 1998-1999
Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
*/
#ifndef __FPSR_H__
#define __FPSR_H__
/*
The FPSR is a 32 bit register consisting of 4 parts, each exactly
one byte.
SYSTEM ID
EXCEPTION TRAP ENABLE BYTE
SYSTEM CONTROL BYTE
CUMULATIVE EXCEPTION FLAGS BYTE
The FPCR is a 32 bit register consisting of bit flags.
*/
/* SYSTEM ID
------------
Note: the system id byte is read only */
typedef unsigned int FPSR; /* type for floating point status register */
typedef unsigned int FPCR; /* type for floating point control register */
#define MASK_SYSID 0xff000000
#define BIT_HARDWARE 0x80000000
#define FP_EMULATOR 0x01000000 /* System ID for emulator */
#define FP_ACCELERATOR 0x81000000 /* System ID for FPA11 */
/* EXCEPTION TRAP ENABLE BYTE
----------------------------- */
#define MASK_TRAP_ENABLE 0x00ff0000
#define MASK_TRAP_ENABLE_STRICT 0x001f0000
#define BIT_IXE 0x00100000 /* inexact exception enable */
#define BIT_UFE 0x00080000 /* underflow exception enable */
#define BIT_OFE 0x00040000 /* overflow exception enable */
#define BIT_DZE 0x00020000 /* divide by zero exception enable */
#define BIT_IOE 0x00010000 /* invalid operation exception enable */
/* SYSTEM CONTROL BYTE
---------------------- */
#define MASK_SYSTEM_CONTROL 0x0000ff00
#define MASK_TRAP_STRICT 0x00001f00
#define BIT_AC 0x00001000 /* use alternative C-flag definition
for compares */
#define BIT_EP 0x00000800 /* use expanded packed decimal format */
#define BIT_SO 0x00000400 /* select synchronous operation of FPA */
#define BIT_NE 0x00000200 /* NaN exception bit */
#define BIT_ND 0x00000100 /* no denormalized numbers bit */
/* CUMULATIVE EXCEPTION FLAGS BYTE
---------------------------------- */
#define MASK_EXCEPTION_FLAGS 0x000000ff
#define MASK_EXCEPTION_FLAGS_STRICT 0x0000001f
#define BIT_IXC 0x00000010 /* inexact exception flag */
#define BIT_UFC 0x00000008 /* underflow exception flag */
#define BIT_OFC 0x00000004 /* overfloat exception flag */
#define BIT_DZC 0x00000002 /* divide by zero exception flag */
#define BIT_IOC 0x00000001 /* invalid operation exception flag */
/* Floating Point Control Register
----------------------------------*/
#define BIT_RU 0x80000000 /* rounded up bit */
#define BIT_IE 0x10000000 /* inexact bit */
#define BIT_MO 0x08000000 /* mantissa overflow bit */
#define BIT_EO 0x04000000 /* exponent overflow bit */
#define BIT_SB 0x00000800 /* store bounce */
#define BIT_AB 0x00000400 /* arithmetic bounce */
#define BIT_RE 0x00000200 /* rounding exception */
#define BIT_DA 0x00000100 /* disable FPA */
#define MASK_OP 0x00f08010 /* AU operation code */
#define MASK_PR 0x00080080 /* AU precision */
#define MASK_S1 0x00070000 /* AU source register 1 */
#define MASK_S2 0x00000007 /* AU source register 2 */
#define MASK_DS 0x00007000 /* AU destination register */
#define MASK_RM 0x00000060 /* AU rounding mode */
#define MASK_ALU 0x9cfff2ff /* only ALU can write these bits */
#define MASK_RESET 0x00000d00 /* bits set on reset, all others cleared */
#define MASK_WFC MASK_RESET
#define MASK_RFC ~MASK_RESET
#endif