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

   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/types.h>
   3#include <linux/errno.h>
   4#include <linux/uaccess.h>
   5
   6#include <asm/sfp-machine.h>
   7#include <math-emu/soft-fp.h>
   8
   9int
  10mtfsf(unsigned int FM, u32 *frB)
  11{
  12        u32 mask;
  13        u32 fpscr;
  14
  15        if (likely(FM == 1))
  16                mask = 0x0f;
  17        else if (likely(FM == 0xff))
  18                mask = ~0;
  19        else {
  20                mask = ((FM & 1) |
  21                                ((FM << 3) & 0x10) |
  22                                ((FM << 6) & 0x100) |
  23                                ((FM << 9) & 0x1000) |
  24                                ((FM << 12) & 0x10000) |
  25                                ((FM << 15) & 0x100000) |
  26                                ((FM << 18) & 0x1000000) |
  27                                ((FM << 21) & 0x10000000)) * 15;
  28        }
  29
  30        fpscr = ((__FPU_FPSCR & ~mask) | (frB[1] & mask)) &
  31                ~(FPSCR_VX | FPSCR_FEX | 0x800);
  32
  33        if (fpscr & (FPSCR_VXSNAN | FPSCR_VXISI | FPSCR_VXIDI |
  34                     FPSCR_VXZDZ | FPSCR_VXIMZ | FPSCR_VXVC |
  35                     FPSCR_VXSOFT | FPSCR_VXSQRT | FPSCR_VXCVI))
  36                fpscr |= FPSCR_VX;
  37
  38        /* The bit order of exception enables and exception status
  39         * is the same. Simply shift and mask to check for enabled
  40         * exceptions.
  41         */
  42        if (fpscr & (fpscr >> 22) &  0xf8)
  43                fpscr |= FPSCR_FEX;
  44
  45        __FPU_FPSCR = fpscr;
  46
  47#ifdef DEBUG
  48        printk("%s: %02x %p: %08lx\n", __func__, FM, frB, __FPU_FPSCR);
  49#endif
  50
  51        return 0;
  52}
  53