LXR qemu/target/mips/msa.c

   1/*
   2 * MIPS SIMD Architecture Module Instruction emulation helpers for QEMU.
   3 *
   4 * Copyright (c) 2014 Imagination Technologies
   5 *
   6 * This library is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU Lesser General Public
   8 * License as published by the Free Software Foundation; either
   9 * version 2.1 of the License, or (at your option) any later version.
  10 *
  11 * This library is distributed in the hope that it will be useful,
  12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 * Lesser General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU Lesser General Public
  17 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18 */
  19
  20#include "qemu/osdep.h"
  21#include "cpu.h"
  22#include "internal.h"
  23#include "fpu/softfloat.h"
  24#include "fpu_helper.h"
  25
  26void msa_reset(CPUMIPSState *env)
  27{
  28    if (!ase_msa_available(env)) {
  29        return;
  30    }
  31
  32#ifdef CONFIG_USER_ONLY
  33    /* MSA access enabled */
  34    env->CP0_Config5 |= 1 << CP0C5_MSAEn;
  35    env->CP0_Status |= (1 << CP0St_CU1) | (1 << CP0St_FR);
  36#endif
  37
  38    /*
  39     * MSA CSR:
  40     * - non-signaling floating point exception mode off (NX bit is 0)
  41     * - Cause, Enables, and Flags are all 0
  42     * - round to nearest / ties to even (RM bits are 0)
  43     */
  44    env->active_tc.msacsr = 0;
  45
  46    restore_msa_fp_status(env);
  47
  48    /* tininess detected after rounding.*/
  49    set_float_detect_tininess(float_tininess_after_rounding,
  50                              &env->active_tc.msa_fp_status);
  51
  52    /* clear float_status exception flags */
  53    set_float_exception_flags(0, &env->active_tc.msa_fp_status);
  54
  55    /* clear float_status nan mode */
  56    set_default_nan_mode(0, &env->active_tc.msa_fp_status);
  57
  58    /* set proper signanling bit meaning ("1" means "quiet") */
  59    set_snan_bit_is_one(0, &env->active_tc.msa_fp_status);
  60}
  61