arch/mips/include/asm/fpu_emulator.h

   1 /*
   2  *  This program is free software; you can distribute it and/or modify it
   3  *  under the terms of the GNU General Public License (Version 2) as
   4  *  published by the Free Software Foundation.
   5  *
   6  *  This program is distributed in the hope it will be useful, but WITHOUT
   7  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   8  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   9  *  for more details.
  10  *
  11  *  You should have received a copy of the GNU General Public License along
  12  *  with this program; if not, write to the Free Software Foundation, Inc.,
  13  *  59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
  14  *
  15  * Further private data for which no space exists in mips_fpu_struct.
  16  * This should be subsumed into the mips_fpu_struct structure as
  17  * defined in processor.h as soon as the absurd wired absolute assembler
  18  * offsets become dynamic at compile time.
  19  *
  20  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
  21  * Copyright (C) 2000 MIPS Technologies, Inc.  All rights reserved.
  22  */
  23 #ifndef _ASM_FPU_EMULATOR_H
  24 #define _ASM_FPU_EMULATOR_H
  25
  26 #include <linux/sched.h>
  27 #include <asm/dsemul.h>
  28 #include <asm/thread_info.h>
  29 #include <asm/inst.h>
  30 #include <asm/local.h>
  31 #include <asm/processor.h>
  32
  33 #ifdef CONFIG_DEBUG_FS
  34
  35 struct mips_fpu_emulator_stats {
  36         unsigned long emulated;
  37         unsigned long loads;
  38         unsigned long stores;
  39         unsigned long cp1ops;
  40         unsigned long cp1xops;
  41         unsigned long errors;
  42         unsigned long ieee754_inexact;
  43         unsigned long ieee754_underflow;
  44         unsigned long ieee754_overflow;
  45         unsigned long ieee754_zerodiv;
  46         unsigned long ieee754_invalidop;
  47         unsigned long ds_emul;
  48 };
  49
  50 DECLARE_PER_CPU(struct mips_fpu_emulator_stats, fpuemustats);
  51
  52 #define MIPS_FPU_EMU_INC_STATS(M)                                       \
  53 do {                                                                    \
  54         preempt_disable();                                              \
  55         __this_cpu_inc(fpuemustats.M);                                  \
  56         preempt_enable();                                               \
  57 } while (0)
  58
  59 #else
  60 #define MIPS_FPU_EMU_INC_STATS(M) do { } while (0)
  61 #endif /* CONFIG_DEBUG_FS */
  62
  63 extern int fpu_emulator_cop1Handler(struct pt_regs *xcp,
  64                                     struct mips_fpu_struct *ctx, int has_fpu,
  65                                     void *__user *fault_addr);
  66 void force_fcr31_sig(unsigned long fcr31, void __user *fault_addr,
  67                      struct task_struct *tsk);
  68 int process_fpemu_return(int sig, void __user *fault_addr,
  69                          unsigned long fcr31);
  70 int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
  71                   unsigned long *contpc);
  72 int mm_isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
  73                      unsigned long *contpc);
  74
  75 #define SIGNALLING_NAN 0x7ff800007ff80000LL
  76
  77 static inline void fpu_emulator_init_fpu(void)
  78 {
  79         struct task_struct *t = current;
  80         int i;
  81
  82         for (i = 0; i < 32; i++)
  83                 set_fpr64(&t->thread.fpu.fpr[i], 0, SIGNALLING_NAN);
  84 }
  85
  86 /*
  87  * Mask the FCSR Cause bits according to the Enable bits, observing
  88  * that Unimplemented is always enabled.
  89  */
  90 static inline unsigned long mask_fcr31_x(unsigned long fcr31)
  91 {
  92         return fcr31 & (FPU_CSR_UNI_X |
  93                         ((fcr31 & FPU_CSR_ALL_E) <<
  94                          (ffs(FPU_CSR_ALL_X) - ffs(FPU_CSR_ALL_E))));
  95 }
  96
  97 #endif /* _ASM_FPU_EMULATOR_H */