#include #include extern void __ieee_set_fp_control (unsigned long); extern unsigned long __ieee_get_fp_control (void); static inline unsigned long rdfpcr (void) { unsigned long fpcr; asm ("trapb; mf_fpcr $f0; trapb; stt $f0,%0" : "m="(fpcr)); return fpcr; } static inline void wrfpcr (unsigned long fpcr) { asm volatile ("ldt $f0,%0; trapb; mt_fpcr $f0; trapb" :: "m"(fpcr)); } void __setfpucw (unsigned short fpu_control) { unsigned long fpcr = 0, fpcw = 0; if (!fpu_control) fpu_control = _FPU_DEFAULT; /* first, set dynamic rounding mode: */ fpcr = rdfpcr(); fpcr &= ~FPCR_DYN_MASK; switch (fpu_control & 0xc00) { case _FPU_RC_NEAREST: fpcr |= FPCR_DYN_NORMAL; break; case _FPU_RC_DOWN: fpcr |= FPCR_DYN_MINUS; break; case _FPU_RC_UP: fpcr |= FPCR_DYN_PLUS; break; case _FPU_RC_ZERO: fpcr |= FPCR_DYN_CHOPPED; break; } wrfpcr(fpcr); /* now tell kernel about traps that we like to hear about: */ fpcw = __ieee_get_fp_control(); fpcw &= ~IEEE_TRAP_ENABLE_MASK; if (!(fpu_control & _FPU_MASK_IM)) fpcw |= IEEE_TRAP_ENABLE_INV; if (!(fpu_control & _FPU_MASK_DM)) fpcw |= IEEE_TRAP_ENABLE_UNF; if (!(fpu_control & _FPU_MASK_ZM)) fpcw |= IEEE_TRAP_ENABLE_DZE; if (!(fpu_control & _FPU_MASK_OM)) fpcw |= IEEE_TRAP_ENABLE_OVF; if (!(fpu_control & _FPU_MASK_PM)) fpcw |= IEEE_TRAP_ENABLE_INE; __ieee_set_fp_control(fpcw); __fpu_control = fpu_control; /* update global copy */ }