LXR linux/arch/powerpc/math-emu/mtfsf.c

   1#include <linux/types.h>
   2#include <linux/errno.h>
   3#include <asm/uaccess.h>
   4
   5#include <asm/sfp-machine.h>
   6#include <math-emu/soft-fp.h>
   7
   8int
   9mtfsf(unsigned int FM, u32 *frB)
  10{
  11        u32 mask;
  12        u32 fpscr;
  13
  14        if (likely(FM == 1))
  15                mask = 0x0f;
  16        else if (likely(FM == 0xff))
  17                mask = ~0;
  18        else {
  19                mask = ((FM & 1) |
  20                                ((FM << 3) & 0x10) |
  21                                ((FM << 6) & 0x100) |
  22                                ((FM << 9) & 0x1000) |
  23                                ((FM << 12) & 0x10000) |
  24                                ((FM << 15) & 0x100000) |
  25                                ((FM << 18) & 0x1000000) |
  26                                ((FM << 21) & 0x10000000)) * 15;
  27        }
  28
  29        fpscr = ((__FPU_FPSCR & ~mask) | (frB[1] & mask)) &
  30                ~(FPSCR_VX | FPSCR_FEX | 0x800);
  31
  32        if (fpscr & (FPSCR_VXSNAN | FPSCR_VXISI | FPSCR_VXIDI |
  33                     FPSCR_VXZDZ | FPSCR_VXIMZ | FPSCR_VXVC |
  34                     FPSCR_VXSOFT | FPSCR_VXSQRT | FPSCR_VXCVI))
  35                fpscr |= FPSCR_VX;
  36
  37        /* The bit order of exception enables and exception status
  38         * is the same. Simply shift and mask to check for enabled
  39         * exceptions.
  40         */
  41        if (fpscr & (fpscr >> 22) &  0xf8)
  42                fpscr |= FPSCR_FEX;
  43
  44        __FPU_FPSCR = fpscr;
  45
  46#ifdef DEBUG
  47        printk("%s: %02x %p: %08lx\n", __func__, FM, frB, __FPU_FPSCR);
  48#endif
  49
  50        return 0;
  51}
  52