/* FPU control word bits. C-SKY version.
Copyright (C) 2018-2020 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
<https://www.gnu.org/licenses/>. */
#ifndef _FPU_CONTROL_H
#define _FPU_CONTROL_H
/* C-SKY FPU floating point control register bits.
31-28 -> Reserved (read as 0, write with 0).
27 -> 0: Flush denormalized results to zero.
1: Flush denormalized results to signed minimal normal number.
26 -> Reserved (read as 0, write with 0).
25-24 -> Rounding control.
23-6 -> Reserved (read as 0, write with 0).
5 -> Enable exception for input denormalized exception.
4 -> Enable exception for inexact exception.
3 -> Enable exception for underflow exception.
2 -> Enable exception for overflow exception.
1 -> Enable exception for division by zero exception.
0 -> Enable exception for invalid operation exception.
Rounding Control:
00 - Rounding to nearest (RN).
01 - Rounding toward zero (RZ).
10 - Rounding (up) toward plus infinity (RP).
11 - Rounding (down)toward minus infinity (RM).
C-SKY FPU floating point exception status register bits.
15 -> Accumulate bit for any exception.
14 -> Reserved (read as 0, write with 0).
13 -> Cause bit for input denormalized exception.
12 -> Cause bit for inexact exception.
11 -> Cause bit for underflow exception.
10 -> Cause bit for overflow exception.
9 -> Cause bit for division by zero exception.
8 -> Cause bit for invalid operation exception.
7 -> Flag bit for any exception.
6 -> Reserved (read as 0, write with 0).
5 -> Flag exception for input denormalized exception.
4 -> Flag exception for inexact exception.
3 -> Flag exception for underflow exception.
2 -> Flag exception for overflow exception.
1 -> Flag exception for division by zero exception.
0 -> Flag exception for invalid operation exception. */
#include <features.h>
#ifdef __csky_soft_float__
# 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)
# define _FPU_GETFPSR(cw) (cw) = 0
# define _FPU_SETFPSR(cw) (void) (cw)
extern fpu_control_t __fpu_control;
#else /* __csky_soft_float__ */
/* Masking of interrupts. */
# define _FPU_MASK_IDE (1 << 5) /* Input denormalized exception. */
# define _FPU_MASK_IXE (1 << 4) /* Inexact exception. */
# define _FPU_MASK_UFE (1 << 3) /* Underflow exception. */
# define _FPU_MASK_OFE (1 << 2) /* Overflow exception. */
# define _FPU_MASK_DZE (1 << 1) /* Division by zero exception. */
# define _FPU_MASK_IOE (1 << 0) /* Invalid operation exception. */
# define _FPU_MASK_FEA (1 << 15) /* Case for any exception. */
# define _FPU_MASK_FEC (1 << 7) /* Flag for any exception. */
/* Flush denormalized numbers to zero. */
# define _FPU_FLUSH_TZ 0x8000000
/* Rounding control. */
# define _FPU_RC_NEAREST (0x0 << 24) /* RECOMMENDED. */
# define _FPU_RC_ZERO (0x1 << 24)
# define _FPU_RC_UP (0x2 << 24)
# define _FPU_RC_DOWN (0x3 << 24)
# define _FPU_RESERVED 0xf460ffc0 /* Reserved bits in cw. */
# define _FPU_FPSR_RESERVED 0xffff4040
/* The fdlibm code requires strict IEEE double precision arithmetic,
and no interrupts for exceptions, rounding to nearest. */
# define _FPU_DEFAULT 0x00000000
# define _FPU_FPSR_DEFAULT 0x00000000
/* IEEE: same as above, but exceptions. */
# define _FPU_FPCR_IEEE 0x0000001F
# define _FPU_FPSR_IEEE 0x00000000
/* Type of the control word. */
typedef unsigned int fpu_control_t;
/* Macros for accessing the hardware control word. */
# if (__CSKY__ == 2)
# define _FPU_GETCW(cw) __asm__ volatile ("mfcr %0, cr<1, 2>" : "=a" (cw))
# define _FPU_SETCW(cw) __asm__ volatile ("mtcr %0, cr<1, 2>" : : "a" (cw))
# define _FPU_GETFPSR(cw) __asm__ volatile ("mfcr %0, cr<2, 2>" : "=a" (cw))
# define _FPU_SETFPSR(cw) __asm__ volatile ("mtcr %0, cr<2, 2>" : : "a" (cw))
# else
# define _FPU_GETCW(cw) __asm__ volatile ("1: cprcr %0, cpcr2 \n" \
" btsti %0, 31 \n" \
" bt 1b \n" \
" cprcr %0, cpcr1\n" : "=b" (cw))
# define _FPU_SETCW(cw) __asm__ volatile ("1: cprcr r7, cpcr2 \n" \
" btsti r7, 31 \n" \
" bt 1b \n" \
" cpwcr %0, cpcr1 \n" \
: : "b" (cw) : "r7")
# define _FPU_GETFPSR(cw) __asm__ volatile ("1: cprcr %0, cpcr2 \n" \
" btsti %0, 31 \n" \
" bt 1b \n" \
" cprcr %0, cpcr4\n" : "=b" (cw))
# define _FPU_SETFPSR(cw) __asm__ volatile ("1: cprcr r7, cpcr2 \n" \
" btsti r7, 31 \n" \
" bt 1b \n" \
" cpwcr %0, cpcr4 \n" \
: : "b" (cw) : "r7")
# endif /* __CSKY__ != 2 */
/* Default control word set at startup. */
extern fpu_control_t __fpu_control;
#endif /* !__csky_soft_float__ */
#endif /* fpu_control.h */