osfmk/i386/fpu.h

   1 /*
   2  * Copyright (c) 2000-2006 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
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  23  * Please see the License for the specific language governing rights and
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  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28 /*
  29  * @OSF_COPYRIGHT@
  30  */
  31 /*
  32  * Mach Operating System
  33  * Copyright (c) 1991 Carnegie Mellon University
  34  * All Rights Reserved.
  35  *
  36  * Permission to use, copy, modify and distribute this software and its
  37  * documentation is hereby granted, provided that both the copyright
  38  * notice and this permission notice appear in all copies of the
  39  * software, derivative works or modified versions, and any portions
  40  * thereof, and that both notices appear in supporting documentation.
  41  *
  42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
  44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  45  *
  46  * Carnegie Mellon requests users of this software to return to
  47  *
  48  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  49  *  School of Computer Science
  50  *  Carnegie Mellon University
  51  *  Pittsburgh PA 15213-3890
  52  *
  53  * any improvements or extensions that they make and grant Carnegie Mellon
  54  * the rights to redistribute these changes.
  55  */
  56
  57 #ifndef _I386_FPU_H_
  58 #define _I386_FPU_H_
  59
  60 /*
  61  * Macro definitions for routines to manipulate the
  62  * floating-point processor.
  63  */
  64 #include <kern/thread.h>
  65 #include <i386/thread.h>
  66 #include <kern/kern_types.h>
  67 #include <mach/i386/kern_return.h>
  68 #include <mach/i386/thread_status.h>
  69 #include <i386/proc_reg.h>
  70
  71 extern int              fp_kind;
  72
  73 extern void             init_fpu(void);
  74 extern void             fpu_module_init(void);
  75 extern void             fpu_free(
  76                                 struct x86_fpsave_state * fps);
  77 extern kern_return_t    fpu_set_fxstate(
  78                                 thread_t        thr_act,
  79                                 thread_state_t  state);
  80 extern kern_return_t    fpu_get_fxstate(
  81                                 thread_t        thr_act,
  82                                 thread_state_t  state);
  83 extern void             fpu_dup_fxstate(
  84                                 thread_t        parent,
  85                                 thread_t        child);
  86 extern void             fpnoextflt(void);
  87 extern void             fpextovrflt(void);
  88 extern void             fpexterrflt(void);
  89 extern void             fpSSEexterrflt(void);
  90 extern void             fpflush(thread_t);
  91 extern void             fp_setvalid(boolean_t);
  92 extern void             fxsave64(struct x86_fx_save *);
  93 extern void             fxrstor64(struct x86_fx_save *);
  94
  95 /*
  96  * FPU instructions.
  97  */
  98 #define fninit() \
  99         __asm__ volatile("fninit")
 100
 101 #define fnstcw(control) \
 102         __asm__("fnstcw %0" : "=m" (*(unsigned short *)(control)))
 103
 104 #define fldcw(control) \
 105         __asm__ volatile("fldcw %0" : : "m" (*(unsigned short *) &(control)) )
 106
 107 static inline unsigned short
 108 fnstsw(void)
 109 {
 110         unsigned short status;
 111         __asm__ volatile("fnstsw %0" : "=ma" (status));
 112         return(status);
 113 }
 114
 115 #define fnclex() \
 116         __asm__ volatile("fnclex")
 117
 118 #define fnsave(state)  \
 119         __asm__ volatile("fnsave %0" : "=m" (*state))
 120
 121 #define frstor(state) \
 122         __asm__ volatile("frstor %0" : : "m" (state))
 123
 124 #define fwait() \
 125         __asm__("fwait");
 126
 127 #define fxrstor(addr)           __asm("fxrstor %0" : : "m" (*(addr)))
 128 #define fxsave(addr)            __asm __volatile("fxsave %0" : "=m" (*(addr)))
 129
 130 #define FXSAFE() (fp_kind == FP_FXSR)
 131
 132
 133 static inline void clear_fpu(void)
 134 {
 135         set_ts();
 136 }
 137
 138 /*
 139  * Save thread`s FPU context.
 140  */
 141
 142 static inline void fpu_save_context(thread_t thread)
 143 {
 144         struct x86_fpsave_state *ifps;
 145
 146         assert(ml_get_interrupts_enabled() == FALSE);
 147         ifps = (thread)->machine.pcb->ifps;
 148         if (ifps != 0 && !ifps->fp_valid) {
 149                 /* Clear CR0.TS in preparation for the FP context save. In
 150                  * theory, this shouldn't be necessary since a live FPU should
 151                  * indicate that TS is clear. However, various routines
 152                  * (such as sendsig & sigreturn) manipulate TS directly.
 153                  */
 154                 clear_ts();
 155                 /* registers are in FPU - save to memory */
 156                 ifps->fp_valid = TRUE;
 157
 158                 if (!thread_is_64bit(thread) || is_saved_state32(thread->machine.pcb->iss)) {
 159                         /* save the compatibility/legacy mode XMM+x87 state */
 160                         fxsave(&ifps->fx_save_state);
 161                         ifps->fp_save_layout = FXSAVE32;
 162                 }
 163                 else {
 164                         /* Execute a brief jump to 64-bit mode to save the 64
 165                          * bit state
 166                          */
 167                         fxsave64(&ifps->fx_save_state);
 168                         ifps->fp_save_layout = FXSAVE64;
 169                 }
 170         }
 171         set_ts();
 172 }
 173
 174 #endif  /* _I386_FPU_H_ */