LXR linux/arch/alpha/include/asm/fpu.h

   1#ifndef __ASM_ALPHA_FPU_H
   2#define __ASM_ALPHA_FPU_H
   3
   4#include <asm/special_insns.h>
   5#include <uapi/asm/fpu.h>
   6
   7/* The following two functions don't need trapb/excb instructions
   8   around the mf_fpcr/mt_fpcr instructions because (a) the kernel
   9   never generates arithmetic faults and (b) call_pal instructions
  10   are implied trap barriers.  */
  11
  12static inline unsigned long
  13rdfpcr(void)
  14{
  15        unsigned long tmp, ret;
  16
  17#if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67)
  18        __asm__ __volatile__ (
  19                "ftoit $f0,%0\n\t"
  20                "mf_fpcr $f0\n\t"
  21                "ftoit $f0,%1\n\t"
  22                "itoft %0,$f0"
  23                : "=r"(tmp), "=r"(ret));
  24#else
  25        __asm__ __volatile__ (
  26                "stt $f0,%0\n\t"
  27                "mf_fpcr $f0\n\t"
  28                "stt $f0,%1\n\t"
  29                "ldt $f0,%0"
  30                : "=m"(tmp), "=m"(ret));
  31#endif
  32
  33        return ret;
  34}
  35
  36static inline void
  37wrfpcr(unsigned long val)
  38{
  39        unsigned long tmp;
  40
  41#if defined(CONFIG_ALPHA_EV6) || defined(CONFIG_ALPHA_EV67)
  42        __asm__ __volatile__ (
  43                "ftoit $f0,%0\n\t"
  44                "itoft %1,$f0\n\t"
  45                "mt_fpcr $f0\n\t"
  46                "itoft %0,$f0"
  47                : "=&r"(tmp) : "r"(val));
  48#else
  49        __asm__ __volatile__ (
  50                "stt $f0,%0\n\t"
  51                "ldt $f0,%1\n\t"
  52                "mt_fpcr $f0\n\t"
  53                "ldt $f0,%0"
  54                : "=m"(tmp) : "m"(val));
  55#endif
  56}
  57
  58static inline unsigned long
  59swcr_update_status(unsigned long swcr, unsigned long fpcr)
  60{
  61        /* EV6 implements most of the bits in hardware.  Collect
  62           the acrued exception bits from the real fpcr.  */
  63        if (implver() == IMPLVER_EV6) {
  64                swcr &= ~IEEE_STATUS_MASK;
  65                swcr |= (fpcr >> 35) & IEEE_STATUS_MASK;
  66        }
  67        return swcr;
  68}
  69
  70extern unsigned long alpha_read_fp_reg (unsigned long reg);
  71extern void alpha_write_fp_reg (unsigned long reg, unsigned long val);
  72extern unsigned long alpha_read_fp_reg_s (unsigned long reg);
  73extern void alpha_write_fp_reg_s (unsigned long reg, unsigned long val);
  74
  75#endif /* __ASM_ALPHA_FPU_H */
  76