LXR linux/arch/mips/kernel/r6000

   1/*
   2 * r6000_fpu.S: Save/restore floating point context for signal handlers.
   3 *
   4 * This file is subject to the terms and conditions of the GNU General Public
   5 * License.  See the file "COPYING" in the main directory of this archive
   6 * for more details.
   7 *
   8 * Copyright (C) 1996 by Ralf Baechle
   9 *
  10 * Multi-arch abstraction and asm macros for easier reading:
  11 * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
  12 */
  13#include <asm/asm.h>
  14#include <asm/fpregdef.h>
  15#include <asm/mipsregs.h>
  16#include <asm/asm-offsets.h>
  17#include <asm/regdef.h>
  18
  19        .set    noreorder
  20        .set    mips2
  21        /* Save floating point context */
  22        LEAF(_save_fp_context)
  23        mfc0    t0,CP0_STATUS
  24        sll     t0,t0,2
  25        bgez    t0,1f
  26         nop
  27
  28        cfc1    t1,fcr31
  29        /* Store the 16 double precision registers */
  30        sdc1    $f0,(SC_FPREGS+0)(a0)
  31        sdc1    $f2,(SC_FPREGS+16)(a0)
  32        sdc1    $f4,(SC_FPREGS+32)(a0)
  33        sdc1    $f6,(SC_FPREGS+48)(a0)
  34        sdc1    $f8,(SC_FPREGS+64)(a0)
  35        sdc1    $f10,(SC_FPREGS+80)(a0)
  36        sdc1    $f12,(SC_FPREGS+96)(a0)
  37        sdc1    $f14,(SC_FPREGS+112)(a0)
  38        sdc1    $f16,(SC_FPREGS+128)(a0)
  39        sdc1    $f18,(SC_FPREGS+144)(a0)
  40        sdc1    $f20,(SC_FPREGS+160)(a0)
  41        sdc1    $f22,(SC_FPREGS+176)(a0)
  42        sdc1    $f24,(SC_FPREGS+192)(a0)
  43        sdc1    $f26,(SC_FPREGS+208)(a0)
  44        sdc1    $f28,(SC_FPREGS+224)(a0)
  45        sdc1    $f30,(SC_FPREGS+240)(a0)
  46        jr      ra
  47         sw     t0,SC_FPC_CSR(a0)
  481:      jr      ra
  49         nop
  50        END(_save_fp_context)
  51
  52/* Restore FPU state:
  53 *  - fp gp registers
  54 *  - cp1 status/control register
  55 *
  56 * We base the decision which registers to restore from the signal stack
  57 * frame on the current content of c0_status, not on the content of the
  58 * stack frame which might have been changed by the user.
  59 */
  60        LEAF(_restore_fp_context)
  61        mfc0    t0,CP0_STATUS
  62        sll     t0,t0,2
  63
  64        bgez    t0,1f
  65         lw     t0,SC_FPC_CSR(a0)
  66        /* Restore the 16 double precision registers */
  67        ldc1    $f0,(SC_FPREGS+0)(a0)
  68        ldc1    $f2,(SC_FPREGS+16)(a0)
  69        ldc1    $f4,(SC_FPREGS+32)(a0)
  70        ldc1    $f6,(SC_FPREGS+48)(a0)
  71        ldc1    $f8,(SC_FPREGS+64)(a0)
  72        ldc1    $f10,(SC_FPREGS+80)(a0)
  73        ldc1    $f12,(SC_FPREGS+96)(a0)
  74        ldc1    $f14,(SC_FPREGS+112)(a0)
  75        ldc1    $f16,(SC_FPREGS+128)(a0)
  76        ldc1    $f18,(SC_FPREGS+144)(a0)
  77        ldc1    $f20,(SC_FPREGS+160)(a0)
  78        ldc1    $f22,(SC_FPREGS+176)(a0)
  79        ldc1    $f24,(SC_FPREGS+192)(a0)
  80        ldc1    $f26,(SC_FPREGS+208)(a0)
  81        ldc1    $f28,(SC_FPREGS+224)(a0)
  82        ldc1    $f30,(SC_FPREGS+240)(a0)
  83        jr      ra
  84         ctc1   t0,fcr31
  851:      jr      ra
  86         nop
  87        END(_restore_fp_context)
  88