1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 
  22 /*
  23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  24  * Use is subject to license terms.
  25  */
  26 
  27 #include <sys/asm_linkage.h>
  28 #include <sys/asm_misc.h>
  29 #include "dboot_xboot.h"
  30 
  31 #if defined(__amd64)
  32 
  33         ENTRY_NP(_start)
  34         /*
  35          * At entry we are passed a (start_info_t *) in %rsi.
  36          */
  37         movq    %rsi, xen_info(%rip)
  38 
  39         /*
  40          * make sure we have sane processor state
  41          */
  42         xorw    %ax, %ax
  43         movw    %ax, %fs
  44         movw    %ax, %gs
  45         pushq   $0
  46         popfq
  47         pushq   $0
  48 
  49         /*
  50          * go off and unpack the kernel bits, adjust page tables, etc.
  51          */
  52         call    startup_kernel
  53 
  54         /*
  55          * we can only setup a stack after startup_kernel().
  56          * Its in the lower part of memroy.
  57          */
  58         leaq    stack_space(%rip), %rsp
  59         addq    $STACK_SIZE, %rsp
  60         andl    $0xfffffff0, %esp
  61 
  62         pushq   $0x0                    /* push a dead-end frame */
  63         pushq   $0x0
  64         movq    %rsp, %rbp
  65 
  66         /*
  67          * when we get back, load the kernel entry point and jump to it
  68          * The address of the xboot_info is the kernel's only argument.
  69          */
  70         movl    entry_addr_low, %esi
  71         movq    $0xffffffff00000000,%rdx
  72         orq     %rdx, %rsi              /* set upper bits of entry addr */
  73 
  74         movl    bi, %edi
  75         call    *%rsi
  76         SET_SIZE(_start)
  77 
  78 #elif defined(__i386)
  79 
  80         ENTRY_NP(_start)
  81         /*
  82          * At entry we are passed a (start_info_t *) in %esi.
  83          */
  84         movl    %esi, xen_info
  85 
  86         /*
  87          * make sure we have sane processor state
  88          */
  89         cld
  90         xorw    %ax, %ax
  91         movw    %ax, %fs
  92         movw    %ax, %gs
  93 
  94 
  95         /*
  96          * go off and unpack the kernel bits, adjust page tables, etc.
  97          */
  98         call    startup_kernel
  99 
 100         /*
 101          * we can only setup a stack after startup_kernel().
 102          */
 103         movl    $stack_space, %esp      /* load my stack pointer */
 104         addl    $STACK_SIZE, %esp
 105 
 106         pushl   $0x0                    /* push a dead-end frame */
 107         pushl   $0x0
 108         movl    %esp, %ebp
 109 
 110         /*
 111          * when we get back, load the kernel entry point and jump to it
 112          * The address of the xboot_info is the kernel's only argument.
 113          */
 114         movl    entry_addr_low, %esi
 115         movl    bi, %eax
 116         pushl   %eax
 117         call    *%esi
 118         SET_SIZE(_start)
 119 
 120 #endif  /* __i386 */
 121