osfmk/i386/asm64.h

   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 /*
  32  * Long jump to 64-bit space from 32-bit compatibility mode.
  33  */
  34 #define ENTER_64BIT_MODE()                      \
  35         .code32                                 ;\
  36         .byte   0xea    /* far jump longmode */ ;\
  37         .long   1f                              ;\
  38         .word   KERNEL64_CS                     ;\
  39         .code64                                 ;\
  40 1:
  41
  42 /*
  43  * Here in long mode but still running below 4G.
  44  * "Near" jump into uber-space.
  45  */
  46 #define ENTER_UBERSPACE()                       \
  47         mov     2f,%rax                         ;\
  48         jmp     *%rax                           ;\
  49 2:      .long   3f                              ;\
  50         .long   KERNEL_UBER_BASE_HI32           ;\
  51 3:
  52
  53 /*
  54  * Long jump to 32-bit compatibility mode from 64-bit space.
  55  */
  56 #define ENTER_COMPAT_MODE()                     \
  57         ljmp    *(%rip)                         ;\
  58         .long   4f                              ;\
  59         .word   KERNEL32_CS                     ;\
  60         .code32                                 ;\
  61 4:
  62