1/* 2 * Copyright (c) 2006 Apple Computer, Inc. All rights reserved. 3 * 4 * @APPLE_OSREFERENCE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. The rights granted to you under the License 10 * may not be used to create, or enable the creation or redistribution of, 11 * unlawful or unlicensed copies of an Apple operating system, or to 12 * circumvent, violate, or enable the circumvention or violation of, any 13 * terms of an Apple operating system software license agreement. 14 * 15 * Please obtain a copy of the License at 16 * http://www.opensource.apple.com/apsl/ and read it before using this file. 17 * 18 * The Original Code and all software distributed under the License are 19 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 20 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 21 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 22 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 23 * Please see the License for the specific language governing rights and 24 * limitations under the License. 25 * 26 * @APPLE_OSREFERENCE_LICENSE_HEADER_END@ 27 */ 28 29/* Helper macros for 64-bit mode switching */ 30 31#if __i386__ 32/* 33 * Long jump to 64-bit space from 32-bit compatibility mode. 34 */ 35#define ENTER_64BIT_MODE() \ 36 .code32 ;\ 37 .byte 0xea /* far jump longmode */ ;\ 38 .long 1f ;\ 39 .word KERNEL64_CS ;\ 40 .code64 ;\ 411: 42 43/* 44 * Here in long mode but still running below 4G. 45 * "Near" jump into uber-space. 46 */ 47#define ENTER_UBERSPACE() \ 48 mov 2f,%rax ;\ 49 jmp *%rax ;\ 502: .long 3f ;\ 51 .long KERNEL_UBER_BASE_HI32 ;\ 523: 53 54/* 55 * Long jump to 32-bit compatibility mode from 64-bit space. 56 */ 57#define ENTER_COMPAT_MODE() \ 58 ljmp *(%rip) ;\ 59 .long 4f ;\ 60 .word KERNEL32_CS ;\ 61 .code32 ;\ 624: 63 64#else 65 66/* 67 * Long jump to 64-bit space from 32-bit compatibility mode. 68 * Effected, in fact, by a long return .. 69 * - we push the 64-bit kernel code selector KERNEL64_CS 70 * - call .+1 to get EIP on stack 71 * - adjust return address after lret 72 * - lret to return to next instruction but 64-bit mode. 73 */ 74#define ENTER_64BIT_MODE() \ 75 push $KERNEL64_CS ;\ 76 call 1f ;\ 771: addl $(2f-1b), (%esp) ;\ 78 lret ;\ 792: .code64 80 81/* 82 * Long jump to 32-bit compatibility mode from 64-bit space. 83 * Effected by long return similar to ENTER_64BIT_MODE. 84 */ 85#define ENTER_COMPAT_MODE() \ 86 call 3f ;\ 873: addq $(4f-3b), (%rsp) ;\ 88 movl $KERNEL32_CS, 4(%rsp) ;\ 89 lret ;\ 904: .code32 91 92#endif 93