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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:17:27 +0000
commitf215e02bf85f68d3a6106c2a1f4f7f063f819064 (patch)
tree6bb5b92c046312c4e95ac2620b10ddf482d3fa8b /src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-SelRealModeDataToProtFar16.asm
parentInitial commit. (diff)
downloadvirtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.tar.xz
virtualbox-f215e02bf85f68d3a6106c2a1f4f7f063f819064.zip
Adding upstream version 7.0.14-dfsg.upstream/7.0.14-dfsg
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-SelRealModeDataToProtFar16.asm')
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diff --git a/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-SelRealModeDataToProtFar16.asm b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-SelRealModeDataToProtFar16.asm
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+++ b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-SelRealModeDataToProtFar16.asm
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+; $Id: bs3-cmn-SelRealModeDataToProtFar16.asm $
+;; @file
+; BS3Kit - Bs3SelRealModeDataToProtFar16.
+;
+
+;
+; 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"
+
+
+;*********************************************************************************************************************************
+;* External Symbols *
+;*********************************************************************************************************************************
+BS3_BEGIN_DATA16 ; For real mode segment value.
+BS3_BEGIN_SYSTEM16 ; Ditto.
+
+TMPL_BEGIN_TEXT
+%if TMPL_BITS == 16
+CPU 8086
+%endif
+
+
+;;
+; @cproto BS3_CMN_PROTO_NOSB(uint32_t, Bs3SelRealModeDataToProtFar16,(uint32_t uFar1616));
+;
+; @uses Only return registers (ax:dx, eax, eax)
+; @remarks No 20h scratch area requirements.
+;
+BS3_PROC_BEGIN_CMN Bs3SelRealModeDataToProtFar16, BS3_PBC_NEAR ; Far stub generated by the makefile/bs3kit.h.
+ push xBP
+ mov xBP, xSP
+
+ ;
+ ; See if it's our default 16-bit data, stack or system data segment.
+ ;
+%if TMPL_BITS == 16
+ mov ax, [xBP + xCB + cbCurRetAddr + 2]
+%elif TMPL_BITS == 32
+ movzx eax, word [xBP + xCB + cbCurRetAddr + 2]
+%else
+ mov eax, ecx
+ shr eax, 16
+%endif
+ cmp ax, 0
+ jnz .not_stack
+ mov ax, BS3_SEL_R0_SS16
+
+.quick_return:
+%if TMPL_BITS == 16
+ mov dx, ax
+ mov ax, [xBP + xCB + cbCurRetAddr]
+%elif TMPL_BITS == 32
+ shl eax, 16
+ mov ax, word [xBP + xCB + cbCurRetAddr]
+%else
+ shl eax, 16
+ mov ax, cx
+%endif
+
+.return:
+ pop xBP
+ BS3_HYBRID_RET
+
+.not_stack:
+ cmp ax, BS3KIT_GRPNM_DATA16
+ jne .not_dgroup
+ mov ax, BS3_SEL_R0_DS16
+ jmp .quick_return
+
+.not_dgroup:
+ cmp ax, BS3SYSTEM16
+ jne .not_system16
+ mov ax, BS3_SEL_SYSTEM16
+ jmp .quick_return
+
+ ;
+ ; Compute flat address and translate it to tiled.
+ ;
+.not_system16:
+%if TMPL_BITS == 16
+ push cx
+
+ ; Calc flat address.
+ mov dx, ax
+ mov cl, 12
+ shr dx, cl
+ mov cl, 4
+ shl ax, cl
+ add ax, [xBP + xCB + cbCurRetAddr]
+ adc dx, 0
+
+ ; Convert upper 16-bit to tiled selector.
+ mov cl, X86_SEL_SHIFT
+ shl dx, cl
+ add dx, BS3_SEL_TILED
+
+ pop cx
+%else
+ ; Calc flat address.
+ shl eax, 4
+ %if TMPL_BITS == 32
+ add ax, [xBP + xCB + cbCurRetAddr]
+ %else
+ add ax, cx
+ %endif
+ jnc .no_carry
+ add eax, 10000h
+.no_carry:
+
+ ; Convert upper 16-bit to tiled selector.
+ rol eax, 16
+ shl ax, X86_SEL_SHIFT
+ add ax, BS3_SEL_TILED
+ ror eax, 16
+%endif
+ jmp .return
+BS3_PROC_END_CMN Bs3SelRealModeDataToProtFar16
+