diff options
Diffstat (limited to 'libc/sysdeps/linux/arm/fpu_control.h')
-rw-r--r-- | libc/sysdeps/linux/arm/fpu_control.h | 192 |
1 files changed, 32 insertions, 160 deletions
diff --git a/libc/sysdeps/linux/arm/fpu_control.h b/libc/sysdeps/linux/arm/fpu_control.h index 1b9b09df6..05ac6a03c 100644 --- a/libc/sysdeps/linux/arm/fpu_control.h +++ b/libc/sysdeps/linux/arm/fpu_control.h @@ -1,6 +1,5 @@ -/* 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. +/* FPU control word definitions. ARM VFP version. + Copyright (C) 2004-2025 Free Software Foundation, Inc. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public @@ -13,13 +12,22 @@ 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/>. */ + License along with the GNU C Library. If not, see + <https://www.gnu.org/licenses/>. */ #ifndef _FPU_CONTROL_H #define _FPU_CONTROL_H -#ifdef __VFP_FP__ +#if !(defined(_LIBC) && !defined(_LIBC_TEST)) && defined(__SOFTFP__) + +#define _FPU_RESERVED 0xffffffff +#define _FPU_DEFAULT 0x00000000 +typedef unsigned int fpu_control_t; +#define _FPU_GETCW(cw) (cw) = 0 +#define _FPU_SETCW(cw) (void) (cw) +extern fpu_control_t __fpu_control; + +#else /* masking of interrupts */ #define _FPU_MASK_IM 0x00000100 /* invalid operation */ @@ -28,175 +36,39 @@ #define _FPU_MASK_UM 0x00000800 /* underflow */ #define _FPU_MASK_PM 0x00001000 /* inexact */ +#define _FPU_MASK_NZCV 0xf0000000 /* NZCV flags */ +#define _FPU_MASK_RM 0x00c00000 /* rounding mode */ +#define _FPU_MASK_EXCEPT 0x00001f1f /* all exception flags */ + /* Some bits in the FPSCR are not yet defined. They must be preserved when modifying the contents. */ -#define _FPU_RESERVED 0x0e08e0e0 +#define _FPU_RESERVED 0x00086060 #define _FPU_DEFAULT 0x00000000 -/* Default + exceptions enabled. */ + +/* 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. */ +#ifdef __SOFTFP__ /* This is fmrx %0, fpscr. */ -#define _FPU_GETCW(cw) \ +# define _FPU_GETCW(cw) \ __asm__ __volatile__ ("mrc p10, 7, %0, cr1, cr0, 0" : "=r" (cw)) /* This is fmxr fpscr, %0. */ -#define _FPU_SETCW(cw) \ +# define _FPU_SETCW(cw) \ __asm__ __volatile__ ("mcr p10, 7, %0, cr1, cr0, 0" : : "r" (cw)) +#else +# define _FPU_GETCW(cw) \ + __asm__ __volatile__ ("vmrs %0, fpscr" : "=r" (cw)) +# define _FPU_SETCW(cw) \ + __asm__ __volatile__ ("vmsr fpscr, %0" : : "r" (cw)) +#endif -#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 /* __SOFTFP__ */ #endif /* _FPU_CONTROL_H */ |