kolibrios/kernel/branches/net/core/fpu.inc

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;;                                                              ;;
;; Copyright (C) KolibriOS team 2004-2011. All rights reserved. ;;
;; Distributed under terms of the GNU General Public License    ;;
;;                                                              ;;
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

$Revision $


init_fpu:
        clts
        fninit

        bt      [cpu_caps], CAPS_SSE
        jnc     .no_SSE

        mov     ebx, cr4
        mov     ecx, cr0
        or      ebx, CR4_OSFXSR+CR4_OSXMMEXPT
        mov     cr4, ebx

        and     ecx, not (CR0_MP+CR0_EM)
        or      ecx, CR0_NE
        mov     cr0, ecx

        mov     dword [esp-4], SSE_INIT
        ldmxcsr [esp-4]

        xorps   xmm0, xmm0
        xorps   xmm1, xmm1
        xorps   xmm2, xmm2
        xorps   xmm3, xmm3
        xorps   xmm4, xmm4
        xorps   xmm5, xmm5
        xorps   xmm6, xmm6
        xorps   xmm7, xmm7
        fxsave  [fpu_data]    ;[eax]
        ret
.no_SSE:
        mov     ecx, cr0
        and     ecx, not CR0_EM
        or      ecx, CR0_MP+CR0_NE
        mov     cr0, ecx
        fnsave  [fpu_data]
        ret

; param
;  eax= 512 bytes memory area

align 4
fpu_save:
        push    ecx
        push    esi
        push    edi

        pushfd
        cli

        clts
        mov     edi, eax

        mov     ecx, [fpu_owner]
        mov     esi, [CURRENT_TASK]
        cmp     ecx, esi
        jne     .save

        call    save_context
        jmp     .exit
.save:
        mov     [fpu_owner], esi

        shl     ecx, 8
        mov     eax, [ecx+SLOT_BASE+APPDATA.fpu_state]

        call    save_context

        shl     esi, 8
        mov     esi, [esi+SLOT_BASE+APPDATA.fpu_state]
        mov     ecx, 512/4
        cld
        rep movsd
        fninit
.exit:
        popfd
        pop     edi
        pop     esi
        pop     ecx
        ret

align 4
save_context:
        bt      [cpu_caps], CAPS_SSE
        jnc     .no_SSE

        fxsave  [eax]
        ret
.no_SSE:
        fnsave  [eax]
        ret

align 4
fpu_restore:
        push    ecx
        push    esi

        mov     esi, eax

        pushfd
        cli

        mov     ecx, [fpu_owner]
        mov     eax, [CURRENT_TASK]
        cmp     ecx, eax
        jne     .copy

        clts
        bt      [cpu_caps], CAPS_SSE
        jnc     .no_SSE

        fxrstor [esi]
        popfd
        pop     esi
        pop     ecx
        ret
.no_SSE:
        fnclex                  ;fix possible problems
        frstor  [esi]
        popfd
        pop     esi
        pop     ecx
        ret
.copy:
        shl     eax, 8
        mov     edi, [eax+SLOT_BASE+APPDATA.fpu_state]
        mov     ecx, 512/4
        cld
        rep movsd
        popfd
        pop     esi
        pop     ecx
        ret

align 4
except_7:                  ;#NM exception handler
        save_ring3_context
        clts
        mov     ax, app_data;
        mov     ds, ax
        mov     es, ax

        mov     ebx, [fpu_owner]
        cmp     ebx, [CURRENT_TASK]
        je      .exit

        shl     ebx, 8
        mov     eax, [ebx+SLOT_BASE+APPDATA.fpu_state]
        bt      [cpu_caps], CAPS_SSE
        jnc     .no_SSE

        fxsave  [eax]
        mov     ebx, [CURRENT_TASK]
        mov     [fpu_owner], ebx
        shl     ebx, 8
        mov     eax, [ebx+SLOT_BASE+APPDATA.fpu_state]
        fxrstor [eax]
.exit:
        restore_ring3_context
        iret

.no_SSE:
        fnsave  [eax]
        mov     ebx, [CURRENT_TASK]
        mov     [fpu_owner], ebx
        shl     ebx, 8
        mov     eax, [ebx+SLOT_BASE+APPDATA.fpu_state]
        frstor  [eax]
        restore_ring3_context
        iret

iglobal
  fpu_owner dd 0
endg