diff options
Diffstat (limited to 'src/VBox/ValidationKit/bootsectors/bs3kit/bs3-c16-SwitchFromV86To16BitAndCallC.asm')
| -rw-r--r-- | src/VBox/ValidationKit/bootsectors/bs3kit/bs3-c16-SwitchFromV86To16BitAndCallC.asm | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-c16-SwitchFromV86To16BitAndCallC.asm b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-c16-SwitchFromV86To16BitAndCallC.asm new file mode 100644 index 00000000..5e0fcb90 --- /dev/null +++ b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-c16-SwitchFromV86To16BitAndCallC.asm @@ -0,0 +1,109 @@ +; $Id: bs3-c16-SwitchFromV86To16BitAndCallC.asm $ +;; @file +; BS3Kit - Bs3SwitchFromV86To16BitAndCallC +; + +; +; Copyright (C) 2007-2023 Oracle and/or its affiliates. +; +; This file is part of VirtualBox base platform packages, as +; available from https://www.virtualbox.org. +; +; This program is free software; you can redistribute it and/or +; modify it under the terms of the GNU General Public License +; as published by the Free Software Foundation, in version 3 of the +; License. +; +; This program is distributed in the hope that it will be useful, but +; WITHOUT ANY WARRANTY; without even the implied warranty of +; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU +; General Public License for more details. +; +; You should have received a copy of the GNU General Public License +; along with this program; if not, see <https://www.gnu.org/licenses>. +; +; The contents of this file may alternatively be used under the terms +; of the Common Development and Distribution License Version 1.0 +; (CDDL), a copy of it is provided in the "COPYING.CDDL" file included +; in the VirtualBox distribution, in which case the provisions of the +; CDDL are applicable instead of those of the GPL. +; +; You may elect to license modified versions of this file under the +; terms and conditions of either the GPL or the CDDL or both. +; +; SPDX-License-Identifier: GPL-3.0-only OR CDDL-1.0 +; + +;********************************************************************************************************************************* +;* Header Files * +;********************************************************************************************************************************* +%include "bs3kit-template-header.mac" +%if TMPL_BITS != 16 + %error "16-bit only" +%endif + + +;********************************************************************************************************************************* +;* External Symbols * +;********************************************************************************************************************************* +%ifdef BS3_STRICT +BS3_EXTERN_DATA16 g_bBs3CurrentMode +TMPL_BEGIN_TEXT +BS3_EXTERN_CMN Bs3Panic +%endif +BS3_EXTERN_CMN Bs3SwitchTo16Bit +BS3_EXTERN_CMN Bs3SwitchTo16BitV86 +BS3_EXTERN_CMN Bs3SelRealModeCodeToProtMode + + +;; +; @cproto BS3_CMN_PROTO_STUB(int, Bs3SwitchFromV86To16BitAndCallC,(FPFNBS3FAR fpfnCall, unsigned cbParams, ...)); +; +BS3_PROC_BEGIN_CMN Bs3SwitchFromV86To16BitAndCallC, BS3_PBC_HYBRID + inc bp + push bp + mov bp, sp + + ; + ; Push the arguments first. + ; + mov ax, si ; save si + mov si, [bp + 2 + cbCurRetAddr + 4] +%ifdef BS3_STRICT + test si, 1 + jz .cbParams_ok + call Bs3Panic +.cbParams_ok: + test byte [g_bBs3CurrentMode], BS3_MODE_CODE_V86 + jnz .mode_ok + call Bs3Panic +.mode_ok: +%endif + +.push_more: + push word [bp + 2 + cbCurRetAddr + 4 + 2 + si - 2] + sub si, 2 + jnz .push_more + mov si, ax ; restore si + + ; + ; Convert the code segment to a 16-bit prot mode selector + ; + push word [bp + 2 + cbCurRetAddr + 2] + call Bs3SelRealModeCodeToProtMode + mov [bp + 2 + cbCurRetAddr + 2], ax + add sp, 2 + + ; + ; Switch mode. + ; + call Bs3SwitchTo16Bit + call far [bp + 2 + cbCurRetAddr] + call Bs3SwitchTo16BitV86 + + mov sp, bp + pop bp + dec bp + BS3_HYBRID_RET +BS3_PROC_END_CMN Bs3SwitchFromV86To16BitAndCallC + |