/* * Copyright (c) 2006 Apple Computer, Inc. All rights reserved. * * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ * * This file contains Original Code and/or Modifications of Original Code * as defined in and that are subject to the Apple Public Source License * Version 2.0 (the 'License'). You may not use this file except in * compliance with the License. The rights granted to you under the License * may not be used to create, or enable the creation or redistribution of, * unlawful or unlicensed copies of an Apple operating system, or to * circumvent, violate, or enable the circumvention or violation of, any * terms of an Apple operating system software license agreement. * * Please obtain a copy of the License at * http://www.opensource.apple.com/apsl/ and read it before using this file. * * The Original Code and all software distributed under the License are * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. * Please see the License for the specific language governing rights and * limitations under the License. * * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ */ /* Helper macros for 64-bit mode switching */ #if __i386__ /* * Long jump to 64-bit space from 32-bit compatibility mode. */ #define ENTER_64BIT_MODE() \ .code32 ;\ .byte 0xea /* far jump longmode */ ;\ .long 1f ;\ .word KERNEL64_CS ;\ .code64 ;\ 1: /* * Here in long mode but still running below 4G. * "Near" jump into uber-space. */ #define ENTER_UBERSPACE() \ mov 2f,%rax ;\ jmp *%rax ;\ 2: .long 3f ;\ .long KERNEL_UBER_BASE_HI32 ;\ 3: /* * Long jump to 32-bit compatibility mode from 64-bit space. */ #define ENTER_COMPAT_MODE() \ ljmp *(%rip) ;\ .long 4f ;\ .word KERNEL32_CS ;\ .code32 ;\ 4: #else /* * Long jump to 64-bit space from 32-bit compatibility mode. * Effected, in fact, by a long return .. * - we push the 64-bit kernel code selector KERNEL64_CS * - call .+1 to get EIP on stack * - adjust return address after lret * - lret to return to next instruction but 64-bit mode. */ #define ENTER_64BIT_MODE() \ push $KERNEL64_CS ;\ call 1f ;\ 1: addl $(2f-1b), (%esp) ;\ lret ;\ 2: .code64 /* * Long jump to 32-bit compatibility mode from 64-bit space. * Effected by long return similar to ENTER_64BIT_MODE. */ #define ENTER_COMPAT_MODE() \ call 3f ;\ 3: addq $(4f-3b), (%rsp) ;\ movl $KERNEL32_CS, 4(%rsp) ;\ lret ;\ 4: .code32 #endif