diff options
Diffstat (limited to 'i386/pc/rv86/rv86_real_int_asm.S')
| -rw-r--r-- | i386/pc/rv86/rv86_real_int_asm.S | 119 |
1 files changed, 119 insertions, 0 deletions
diff --git a/i386/pc/rv86/rv86_real_int_asm.S b/i386/pc/rv86/rv86_real_int_asm.S new file mode 100644 index 0000000..54b1b9b --- /dev/null +++ b/i386/pc/rv86/rv86_real_int_asm.S @@ -0,0 +1,119 @@ +/* + * Copyright (c) 1995 The University of Utah and + * the Computer Systems Laboratory at the University of Utah (CSL). + * All rights reserved. + * + * Permission to use, copy, modify and distribute this software is hereby + * granted provided that (1) source code retains these copyright, permission, + * and disclaimer notices, and (2) redistributions including binaries + * reproduce the notices in supporting documentation, and (3) all advertising + * materials mentioning features or use of this software display the following + * acknowledgement: ``This product includes software developed by the + * Computer Systems Laboratory at the University of Utah.'' + * + * THE UNIVERSITY OF UTAH AND CSL ALLOW FREE USE OF THIS SOFTWARE IN ITS "AS + * IS" CONDITION. THE UNIVERSITY OF UTAH AND CSL DISCLAIM ANY LIABILITY OF + * ANY KIND FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. + * + * CSL requests users of this software to return to csl-dist@cs.utah.edu any + * improvements that they make and grant CSL redistribution rights. + * + * Author: Bryan Ford, University of Utah CSL + */ + +#include <mach/machine/asm.h> +#include <mach/machine/eflags.h> + +#include "trap.h" +#include "i386_asm.h" +#include "pc_asm.h" +#include "trap_asm.h" + + .text + .globl rv86_real_int_asm +rv86_real_int_asm: + + /* Stash our protected-mode stack pointer. */ + movl %esp,EXT(real_tss)+TSS_ESP0 + + /* Load the linear/physical-address data segment into ES, + for easy access to real-mode memory. */ + movl $LINEAR_DS,%edx + movw %dx,%es + + /* Find the physical address of the real-mode interrupt stack (es:ebx). + A 6-byte stack frame has already been allocated on it. */ + movl EXT(rv86_usp)+4,%ebx + shll $4,%ebx + addl EXT(rv86_usp),%ebx + + /* Store the magic return pointer into the real-mode interrupt stack frame. */ + movl EXT(rv86_rp),%edx + movl %edx,%es:(%ebx) + movw RCD_FLAGS(%eax),%dx + movw %dx,%es:4(%ebx) + + /* Find the address of the real mode interrupt vector (es:esi). */ + shll $2,%esi + + /* Build the v86 trap frame. */ + xorl %edx,%edx + movw RCD_GS(%eax),%dx + pushl %edx + movw RCD_FS(%eax),%dx + pushl %edx + movw RCD_DS(%eax),%dx + pushl %edx + movw RCD_ES(%eax),%dx + pushl %edx + pushl EXT(rv86_usp)+4 + pushl EXT(rv86_usp) + movl $EFL_VM+EFL_IOPL_USER,%ecx + orw RCD_FLAGS(%eax),%cx + andl $-1-EFL_IF-EFL_TF,%ecx + pushl %ecx + movw %es:2(%esi),%edx + pushl %edx + movw %es:(%esi),%edx + pushl %edx + + /* Load the requested register state. */ + movl RCD_EDI(%eax),%edi + movl RCD_ESI(%eax),%esi + movl RCD_EBP(%eax),%ebp + movl RCD_EBX(%eax),%ebx + movl RCD_EDX(%eax),%edx + movl RCD_ECX(%eax),%ecx + movl RCD_EAX(%eax),%eax + + /* Drop into v86 mode. */ + iret + +ENTRY(rv86_return) + + /* Restore the kernel segment registers. */ + movw %ss,%ax + movw %ax,%ds + movw %ax,%es + + /* Retrieve the real_call_data pointer from rv86_real_int_asm's stack frame. */ + movl TR_V86SIZE+4(%esp),%eax + + /* Stash the final register state. */ + movl TR_EDI(%esp),%edx; movl %edx,RCD_EDI(%eax) + movl TR_ESI(%esp),%edx; movl %edx,RCD_ESI(%eax) + movl TR_EBP(%esp),%edx; movl %edx,RCD_EBP(%eax) + movl TR_EBX(%esp),%edx; movl %edx,RCD_EBX(%eax) + movl TR_EDX(%esp),%edx; movl %edx,RCD_EDX(%eax) + movl TR_ECX(%esp),%edx; movl %edx,RCD_ECX(%eax) + movl TR_EAX(%esp),%edx; movl %edx,RCD_EAX(%eax) + movl TR_EFLAGS(%esp),%edx; movw %dx,RCD_FLAGS(%eax) + movl TR_V86_ES(%esp),%edx; movw %dx,RCD_ES(%eax) + movl TR_V86_DS(%esp),%edx; movw %dx,RCD_DS(%eax) + movl TR_V86_FS(%esp),%edx; movw %dx,RCD_FS(%eax) + movl TR_V86_GS(%esp),%edx; movw %dx,RCD_GS(%eax) + + /* Return from the call to rv86_real_int_asm. */ + lea TR_V86SIZE(%esp),%esp + ret + |