diff options
Diffstat (limited to 'src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-Trap16Init.c')
| -rw-r--r-- | src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-Trap16Init.c | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-Trap16Init.c b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-Trap16Init.c new file mode 100644 index 00000000..be43260e --- /dev/null +++ b/src/VBox/ValidationKit/bootsectors/bs3kit/bs3-cmn-Trap16Init.c @@ -0,0 +1,129 @@ +/* $Id: bs3-cmn-Trap16Init.c $ */ +/** @file + * BS3Kit - Bs3Trap16Init + */ + +/* + * 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.h" + + +/********************************************************************************************************************************* +* Global Variables * +*********************************************************************************************************************************/ +/* We ASSUME that BS3CLASS16CODE is 64KB aligned, so the low 16-bit of the + flat address matches. Also, these symbols are defined both with + and without underscore prefixes. */ +extern BS3_DECL(void) BS3_FAR_CODE Bs3Trap16DoubleFaultHandler80386(void); +extern BS3_DECL(void) BS3_FAR_CODE Bs3Trap16DoubleFaultHandler80286(void); +extern BS3_DECL(void) BS3_FAR_CODE Bs3Trap16GenericEntries(void); + +/* These two are ugly. Need data access for patching purposes. */ +extern uint8_t BS3_FAR_DATA bs3Trap16GenericTrapOrInt[]; + + +#undef Bs3Trap16InitEx +BS3_CMN_DEF(void, Bs3Trap16InitEx,(bool f386Plus)) +{ + X86TSS16 BS3_FAR *pTss; + unsigned iIdt; + + /* + * If 386 or later, patch the trap handler code to not jump to the 80286 + * code but continue with the next instruction (the 386+ code). + */ + if (f386Plus) + { + uint8_t BS3_FAR_DATA *pbFunction = &bs3Trap16GenericTrapOrInt[0]; +#if ARCH_BITS == 16 + if (g_bBs3CurrentMode != BS3_MODE_RM) + pbFunction = (uint8_t BS3_FAR_DATA *)BS3_FP_MAKE(BS3_SEL_TILED + 1, BS3_FP_OFF(pbFunction)); +#endif + pbFunction[1] = 0; + pbFunction[2] = 0; + } + + /* + * IDT entries, except the system call gate. + */ + for (iIdt = 0; iIdt < 256; iIdt++) + if (iIdt != BS3_TRAP_SYSCALL) + Bs3Trap16SetGate(iIdt, X86_SEL_TYPE_SYS_286_INT_GATE, 0 /*bDpl*/, + BS3_SEL_R0_CS16, (uint16_t)(uintptr_t)Bs3Trap16GenericEntries + iIdt * 8, 0 /*cParams*/); + + /* + * Initialize the normal TSS so we can do ring transitions via the IDT. + */ + pTss = &Bs3Tss16; + Bs3MemZero(pTss, sizeof(*pTss)); + pTss->sp0 = BS3_ADDR_STACK_R0; + pTss->ss0 = BS3_SEL_R0_SS16; + pTss->sp1 = BS3_ADDR_STACK_R1; + pTss->ss1 = BS3_SEL_R1_SS16 | 1; + pTss->sp2 = BS3_ADDR_STACK_R2; + pTss->ss2 = BS3_SEL_R2_SS16 | 2; + + /* + * Initialize the double fault TSS. + * cr3 is filled in by switcher code, when needed. + */ + pTss = &Bs3Tss16DoubleFault; + Bs3MemZero(pTss, sizeof(*pTss)); + pTss->sp0 = BS3_ADDR_STACK_R0; + pTss->ss0 = BS3_SEL_R0_SS16; + pTss->sp1 = BS3_ADDR_STACK_R1; + pTss->ss1 = BS3_SEL_R1_SS16 | 1; + pTss->sp2 = BS3_ADDR_STACK_R2; + pTss->ss2 = BS3_SEL_R2_SS16 | 2; + pTss->ip = (uint16_t)(uintptr_t)(f386Plus ? &Bs3Trap16DoubleFaultHandler80386 : &Bs3Trap16DoubleFaultHandler80286); + pTss->flags = X86_EFL_1; + pTss->sp = BS3_ADDR_STACK_R0_IST1; + pTss->es = BS3_SEL_R0_DS16; + pTss->ds = BS3_SEL_R0_DS16; + pTss->cs = BS3_SEL_R0_CS16; + pTss->ss = BS3_SEL_R0_SS16; + pTss->dx = f386Plus; + + Bs3Trap16SetGate(X86_XCPT_DF, X86_SEL_TYPE_SYS_TASK_GATE, 0 /*bDpl*/, BS3_SEL_TSS16_DF, 0, 0 /*cParams*/); +} + + +#undef Bs3Trap16Init +BS3_CMN_DEF(void, Bs3Trap16Init,(void)) +{ + BS3_CMN_NM(Bs3Trap16InitEx)((g_uBs3CpuDetected & BS3CPU_TYPE_MASK) >= BS3CPU_80386); +} + |