/* FPU control word definitions. ARM version. Copyright (C) 1996, 1997, 1998, 2000 Free Software Foundation, Inc. This file is part of the GNU C Library. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version. The GNU C Library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with the GNU C Library; if not, see <http://www.gnu.org/licenses/>. */ #ifndef _FPU_CONTROL_H #define _FPU_CONTROL_H #ifdef __VFP_FP__ /* masking of interrupts */ #define _FPU_MASK_IM 0x00000100 /* invalid operation */ #define _FPU_MASK_ZM 0x00000200 /* divide by zero */ #define _FPU_MASK_OM 0x00000400 /* overflow */ #define _FPU_MASK_UM 0x00000800 /* underflow */ #define _FPU_MASK_PM 0x00001000 /* inexact */ /* Some bits in the FPSCR are not yet defined. They must be preserved when modifying the contents. */ #define _FPU_RESERVED 0x0e08e0e0 #define _FPU_DEFAULT 0x00000000 /* Default + exceptions enabled. */ #define _FPU_IEEE (_FPU_DEFAULT | 0x00001f00) /* Type of the control word. */ typedef unsigned int fpu_control_t; /* Macros for accessing the hardware control word. */ /* This is fmrx %0, fpscr. */ #define _FPU_GETCW(cw) \ __asm__ __volatile__ ("mrc p10, 7, %0, cr1, cr0, 0" : "=r" (cw)) /* This is fmxr fpscr, %0. */ #define _FPU_SETCW(cw) \ __asm__ __volatile__ ("mcr p10, 7, %0, cr1, cr0, 0" : : "r" (cw)) #elif defined __MAVERICK__ /* DSPSC register: (from EP9312 User's Guide) * * bits 31..29 - DAID * bits 28..26 - HVID * bits 25..24 - RSVD * bit 23 - ISAT * bit 22 - UI * bit 21 - INT * bit 20 - AEXC * bits 19..18 - SAT * bits 17..16 - FCC * bit 15 - V * bit 14 - FWDEN * bit 13 - Invalid * bit 12 - Denorm * bits 11..10 - RM * bits 9..5 - IXE, UFE, OFE, RSVD, IOE * bits 4..0 - IX, UF, OF, RSVD, IO */ /* masking of interrupts */ #define _FPU_MASK_IM (1 << 5) /* invalid operation */ #define _FPU_MASK_ZM 0 /* divide by zero */ #define _FPU_MASK_OM (1 << 7) /* overflow */ #define _FPU_MASK_UM (1 << 8) /* underflow */ #define _FPU_MASK_PM (1 << 9) /* inexact */ #define _FPU_MASK_DM 0 /* denormalized operation */ #define _FPU_RESERVED 0xfffff000 /* These bits are reserved. */ #define _FPU_DEFAULT 0x00b00000 /* Default value. */ #define _FPU_IEEE 0x00b003a0 /* Default + exceptions enabled. */ /* Type of the control word. */ typedef unsigned int fpu_control_t; /* Macros for accessing the hardware control word. */ #define _FPU_GETCW(cw) ({ \ register int __t1, __t2; \ \ __asm__ __volatile__ ( \ "cfmvr64l %1, mvdx0\n\t" \ "cfmvr64h %2, mvdx0\n\t" \ "cfmv32sc mvdx0, dspsc\n\t" \ "cfmvr64l %0, mvdx0\n\t" \ "cfmv64lr mvdx0, %1\n\t" \ "cfmv64hr mvdx0, %2" \ : "=r" (cw), "=r" (__t1), "=r" (__t2) \ ); \ }) #define _FPU_SETCW(cw) ({ \ register int __t0, __t1, __t2; \ \ __asm__ __volatile__ ( \ "cfmvr64l %1, mvdx0\n\t" \ "cfmvr64h %2, mvdx0\n\t" \ "cfmv64lr mvdx0, %0\n\t" \ "cfmvsc32 dspsc, mvdx0\n\t" \ "cfmv64lr mvdx0, %1\n\t" \ "cfmv64hr mvdx0, %2" \ : "=r" (__t0), "=r" (__t1), "=r" (__t2) \ : "0" (cw) \ ); \ }) #else /* !__MAVERICK__ */ /* We have a slight terminology confusion here. On the ARM, the register * we're interested in is actually the FPU status word - the FPU control * word is something different (which is implementation-defined and only * accessible from supervisor mode.) * * The FPSR looks like this: * * 31-24 23-16 15-8 7-0 * | system ID | trap enable | system control | exception flags | * * We ignore the system ID bits; for interest's sake they are: * * 0000 "old" FPE * 1000 FPPC hardware * 0001 FPE 400 * 1001 FPA hardware * * The trap enable and exception flags are both structured like this: * * 7 - 5 4 3 2 1 0 * | reserved | INX | UFL | OFL | DVZ | IVO | * * where a `1' bit in the enable byte means that the trap can occur, and * a `1' bit in the flags byte means the exception has occurred. * * The exceptions are: * * IVO - invalid operation * DVZ - divide by zero * OFL - overflow * UFL - underflow * INX - inexact (do not use; implementations differ) * * The system control byte looks like this: * * 7-5 4 3 2 1 0 * | reserved | AC | EP | SO | NE | ND | * * where the bits mean * * ND - no denormalised numbers (force them all to zero) * NE - enable NaN exceptions * SO - synchronous operation * EP - use expanded packed-decimal format * AC - use alternate definition for C flag on compare operations */ /* masking of interrupts */ #define _FPU_MASK_IM 0x00010000 /* invalid operation */ #define _FPU_MASK_ZM 0x00020000 /* divide by zero */ #define _FPU_MASK_OM 0x00040000 /* overflow */ #define _FPU_MASK_UM 0x00080000 /* underflow */ #define _FPU_MASK_PM 0x00100000 /* inexact */ #define _FPU_MASK_DM 0x00000000 /* denormalized operation */ /* The system id bytes cannot be changed. Only the bottom 5 bits in the trap enable byte can be changed. Only the bottom 5 bits in the system control byte can be changed. Only the bottom 5 bits in the exception flags are used. The exception flags are set by the fpu, but can be zeroed by the user. */ #define _FPU_RESERVED 0xffe0e0e0 /* These bits are reserved. */ /* The fdlibm code requires strict IEEE double precision arithmetic, no interrupts for exceptions, rounding to nearest. Changing the rounding mode will break long double I/O. Turn on the AC bit, the compiler generates code that assumes it is on. */ #define _FPU_DEFAULT 0x00001000 /* Default value. */ #define _FPU_IEEE 0x001f1000 /* Default + exceptions enabled. */ /* Type of the control word. */ typedef unsigned int fpu_control_t; /* Macros for accessing the hardware control word. */ #define _FPU_GETCW(cw) __asm__ ("rfs %0" : "=r" (cw)) #define _FPU_SETCW(cw) __asm__ ("wfs %0" : : "r" (cw)) #endif /* __MAVERICK__ */ #if 0 /* Default control word set at startup. */ extern fpu_control_t __fpu_control; #endif #endif /* _FPU_CONTROL_H */