source: trunk/libs/newlib/src/libgloss/sparc_leon/fpu.S @ 444

/*
 * Copyright (c) 2011 Aeroflex Gaisler
 *
 * BSD license:
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */


#include <asm-leon/asmmacro.h>
#include <asm-leon/leonstack.h>
#include <asm-leon/winmacros.h>
#include <asm-leon/leon.h>
        
#ifndef _SOFT_FLOAT

        .seg    "text"
        /* ------- */
        .weak   _fpdis_enable_svt
        .set    _fpdis_enable_svt,__fpdis_enable_svt
        .weak   _fpdis_enable
        .set    _fpdis_enable,__fpdis_enable
        /* ------- */
        !.global _fpdis_enable,_fpdis_enable_svt
__fpdis_enable_svt:
__fpdis_enable:

        set SPARC_PSR_EF_MASK,%l3
        or %l0,%l3,%l0
        or %l0,0xf00, %l3               ! PIL up to 15, enable fpu
        wr %l3,0, %psr                  ! restore the condition flags, enable fpu
        nop
        nop
        nop
        
        mov     %psr, %l3               ! check if fpu is present
        set SPARC_PSR_EF_MASK,%l4
        andcc   %l3, %l4, %l3
        bne     4f
         nop
        
         ta     0                       ! no fpu present, halt
        
4:
        set     fpustate_current,%l4
        
        ld [%l4],%l4
        set     fpustate_owner,%l5
        ld [%l5],%l5
        cmp     %l4,%l5
        beq     mpfnostore
         nop
        cmp    %g0,%l5
         beq    mpfstore
        nop

        FW_STORE(%l5)
        
mpfstore:       
        set     fpustate_owner,%l6
        st %l4,[%l6]
        cmp    %g0,%l4
         beq    mpfnostore
        nop
        
        FW_LOAD(%l4)

mpfnostore:     
        wr      %l0,0, %psr             ! restore the condition flags, enable fpu
        nop
        nop
        nop
        
        jmpl    %l1,  %g0
        rett    %l2
        
        .seg    "data"

        .global fpustate_default
        .align  8
fpustate_default:
        .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0;
        .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0;
        .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0;
        .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0;
        .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0; .long 0;
        .global fpustate_owner
fpustate_owner:
        .word   fpustate_default                                ! pointer to FPU owning context
        
        .global fpustate_current        
fpustate_current:       
        .word   fpustate_default                                ! pointer to current threads FPU context
                
#endif