LXR linux-old/arch/s390/kernel/s390fpu.c

   1/*
   2 *  arch/s390/kernel/s390fpu.c
   3 *
   4 *  S390 version
   5 *    Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation
   6 *    Author(s): Denis Joseph Barrow (djbarrow@de.ibm.com,barrow_dj@yahoo.com)
   7 *
   8 *  s390fpu.h functions for saving & restoring the fpu state.
   9 *
  10 *  I couldn't inline these as linux/sched.h included half the world
  11 *  & was required to at the task structure.
  12 *  & the functions were too complex to make macros from.
  13 *  ( & as usual I didn't feel like debugging inline code ).
  14 */
  15
  16#include <linux/config.h>
  17#include <linux/sched.h>
  18
  19int save_fp_regs1(s390_fp_regs *fpregs)
  20{
  21        int has_ieee=MACHINE_HAS_IEEE;
  22/*
  23  I don't think we can use STE here as this would load
  24  fp registers 0 & 2 into memory locations 0 & 1 etc. 
  25 */     
  26        asm volatile ("STD   0,8(%0)\n\t"
  27                      "STD   2,24(%0)\n\t"
  28                      "STD   4,40(%0)\n\t"
  29                      "STD   6,56(%0)"
  30                      : 
  31                      : "a" (fpregs)
  32                      : "memory"
  33                );
  34        if(has_ieee)
  35        {
  36                asm volatile ("STFPC 0(%0)\n\t"
  37                              "STD   1,16(%0)\n\t"
  38                              "STD   3,32(%0)\n\t"
  39                              "STD   5,48(%0)\n\t"
  40                              "STD   7,64(%0)\n\t"
  41                              "STD   8,72(%0)\n\t"
  42                              "STD   9,80(%0)\n\t"
  43                              "STD   10,88(%0)\n\t"
  44                              "STD   11,96(%0)\n\t"
  45                              "STD   12,104(%0)\n\t"
  46                              "STD   13,112(%0)\n\t"
  47                              "STD   14,120(%0)\n\t"
  48                              "STD   15,128(%0)\n\t"
  49                              : 
  50                              : "a" (fpregs)
  51                              : "memory"
  52                        );
  53        }
  54        return(has_ieee);
  55}
  56
  57
  58void save_fp_regs(s390_fp_regs *fpregs)
  59{
  60#if CONFIG_MATHEMU
  61        s390_fp_regs *currentfprs;
  62
  63        if(!save_fp_regs1(fpregs))
  64        {
  65                currentfprs=&current->thread.fp_regs;
  66                fpregs->fpc=currentfprs->fpc;
  67                fpregs->fprs[1].d=currentfprs->fprs[1].d;
  68                fpregs->fprs[3].d=currentfprs->fprs[3].d;
  69                fpregs->fprs[5].d=currentfprs->fprs[5].d;
  70                fpregs->fprs[7].d=currentfprs->fprs[7].d;
  71                memcpy(&fpregs->fprs[8].d,&currentfprs->fprs[8].d,sizeof(freg_t)*8);
  72        }
  73#else
  74        save_fp_regs1(fpregs);
  75#endif
  76}
  77
  78
  79int restore_fp_regs1(s390_fp_regs *fpregs)
  80{
  81        int has_ieee=MACHINE_HAS_IEEE;
  82
  83        /* If we don't mask with the FPC_VALID_MASK here
  84         * we've got a very quick shutdown -h now command
  85         * via a kernel specification exception.
  86         */
  87        fpregs->fpc&=FPC_VALID_MASK;
  88        asm volatile ("LD   0,8(%0)\n\t"
  89                      "LD   2,24(%0)\n\t"
  90                      "LD   4,40(%0)\n\t"
  91                      "LD   6,56(%0)"
  92                      : 
  93                      : "a" (fpregs)
  94                      : "memory"
  95                );
  96        if(has_ieee)
  97        {
  98                asm volatile ("LFPC 0(%0)\n\t"
  99                              "LD   1,16(%0)\n\t"
 100                              "LD   3,32(%0)\n\t"
 101                              "LD   5,48(%0)\n\t"
 102                              "LD   7,64(%0)\n\t"
 103                              "LD   8,72(%0)\n\t"
 104                              "LD   9,80(%0)\n\t"
 105                              "LD   10,88(%0)\n\t"
 106                              "LD   11,96(%0)\n\t"
 107                              "LD   12,104(%0)\n\t"
 108                              "LD   13,112(%0)\n\t"
 109                              "LD   14,120(%0)\n\t"
 110                              "LD   15,128(%0)\n\t"
 111                              : 
 112                              : "a" (fpregs)
 113                              : "memory"
 114                        );
 115        }
 116        return(has_ieee);
 117}
 118
 119void restore_fp_regs(s390_fp_regs *fpregs)
 120{
 121#if CONFIG_MATHEMU
 122        s390_fp_regs *currentfprs;
 123
 124        if(!restore_fp_regs1(fpregs))
 125        {
 126                currentfprs=&current->thread.fp_regs;
 127                currentfprs->fpc=fpregs->fpc;
 128                currentfprs->fprs[1].d=fpregs->fprs[1].d;
 129                currentfprs->fprs[3].d=fpregs->fprs[3].d;
 130                currentfprs->fprs[5].d=fpregs->fprs[5].d;
 131                currentfprs->fprs[7].d=fpregs->fprs[7].d;
 132                memcpy(&currentfprs->fprs[8].d,&fpregs->fprs[8].d,sizeof(freg_t)*8);
 133        }
 134#else
 135        restore_fp_regs1(fpregs);
 136#endif
 137}
 138
 139