osfmk/i386/asm64.h

   1 /*
   2  * Copyright (c) 2006 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_OSREFERENCE_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
  10  * License may not be used to create, or enable the creation or
  11  * redistribution of, unlawful or unlicensed copies of an Apple operating
  12  * system, or to circumvent, violate, or enable the circumvention or
  13  * violation of, any terms of an Apple operating system software license
  14  * agreement.
  15  *
  16  * Please obtain a copy of the License at
  17  * http://www.opensource.apple.com/apsl/ and read it before using this
  18  * file.
  19  *
  20  * The Original Code and all software distributed under the License are
  21  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  22  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  23  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  24  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  25  * Please see the License for the specific language governing rights and
  26  * limitations under the License.
  27  *
  28  * @APPLE_LICENSE_OSREFERENCE_HEADER_END@
  29  */
  30
  31 /* Helper macros for 64-bit mode switching */
  32
  33 /*
  34  * Long jump to 64-bit space from 32-bit compatibility mode.
  35  */
  36 #define ENTER_64BIT_MODE()                      \
  37         .code32                                 ;\
  38         .byte   0xea    /* far jump longmode */ ;\
  39         .long   1f                              ;\
  40         .word   KERNEL64_CS                     ;\
  41         .code64                                 ;\
  42 1:
  43
  44 /*
  45  * Here in long mode but still running below 4G.
  46  * "Near" jump into uber-space.
  47  */
  48 #define ENTER_UBERSPACE()                       \
  49         mov     2f,%rax                         ;\
  50         jmp     *%rax                           ;\
  51 2:      .long   3f                              ;\
  52         .long   KERNEL_UBER_BASE_HI32           ;\
  53 3:
  54
  55 /*
  56  * Long jump to 32-bit compatibility mode from 64-bit space.
  57  */
  58 #define ENTER_COMPAT_MODE()                     \
  59         ljmp    *4f                             ;\
  60 4:      .long   5f                              ;\
  61         .word   KERNEL_CS                       ;\
  62         .code32                                 ;\
  63 5:
  64