1/*- 2 * Copyright (c) 2001 Takanori Watanabe <takawata@jp.freebsd.org> 3 * Copyright (c) 2001 Mitsuru IWASAKI <iwasaki@jp.freebsd.org> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 */ 27 28#include <machine/asm.h> 29__FBSDID("$FreeBSD$"); 30 31#define LOCORE 32 33#include <machine/specialreg.h> 34 35 .align 4 36 .code16 37wakeup_16: 38 nop 39 cli 40 41 /* Set up segment registers for real mode */ 42 movw %cs,%ax 43 movw %ax,%ds 44 movw %ax,%ss 45 46 /* Load GDT for real mode */ 47 lgdt physical_gdt 48 49 /* Restore CR2, CR3 and CR4 */ 50 mov previous_cr2,%eax 51 mov %eax,%cr2 52 mov previous_cr3,%eax 53 mov %eax,%cr3 54 mov previous_cr4,%eax 55 mov %eax,%cr4 56 57 /* Transfer some values to protected mode */ 58#define NVALUES 9 59#define TRANSFER_STACK32(val, idx) \ 60 mov val,%eax; \ 61 mov %eax,wakeup_32stack+(idx+1)+(idx*4); 62 63 TRANSFER_STACK32(previous_ss, (NVALUES - 9)) 64 TRANSFER_STACK32(previous_fs, (NVALUES - 8)) 65 TRANSFER_STACK32(previous_ds, (NVALUES - 7)) 66 TRANSFER_STACK32(physical_gdt+2, (NVALUES - 6)) 67 TRANSFER_STACK32(where_to_recover, (NVALUES - 5)) 68 TRANSFER_STACK32(previous_idt+2, (NVALUES - 4)) 69 TRANSFER_STACK32(previous_ldt, (NVALUES - 3)) 70 TRANSFER_STACK32(previous_gdt+2, (NVALUES - 2)) 71 TRANSFER_STACK32(previous_tr, (NVALUES - 1)) 72 TRANSFER_STACK32(previous_cr0, (NVALUES - 0)) 73 74 mov physical_esp,%esi /* to be used in 32bit code */ 75 76 /* Enable protected mode */ 77 mov %cr0,%eax 78 orl $(CR0_PE),%eax 79 mov %eax,%cr0 80 81wakeup_sw32: 82 /* Switch to protected mode by intersegmental jump */ 83 ljmpl $0x8,$0x12345678 /* Code location, to be replaced */ 84 85 .code32 86wakeup_32: 87 /* 88 * Switched to protected mode w/o paging 89 * %esi: KERNEL stack pointer (physical address) 90 */ 91 92 nop 93 94 /* Set up segment registers for protected mode */ 95 movw $0x10,%ax /* KDSEL to segment registers */ 96 movw %ax,%ds 97 movw %ax,%es 98 movw %ax,%gs 99 movw %ax,%ss 100 movw $0x18,%ax /* KPSEL to %fs */ 101 movw %ax,%fs 102 movl %esi,%esp /* physical address stack pointer */ 103 104wakeup_32stack: 105 /* Operands are overwritten in 16bit code */ 106 pushl $0xabcdef09 /* ss + dummy */ 107 pushl $0xabcdef08 /* fs + gs */ 108 pushl $0xabcdef07 /* ds + es */ 109 pushl $0xabcdef06 /* gdt:base (physical address) */ 110 pushl $0xabcdef05 /* recover address */ 111 pushl $0xabcdef04 /* idt:base */ 112 pushl $0xabcdef03 /* ldt + idt:limit */ 113 pushl $0xabcdef02 /* gdt:base */ 114 pushl $0xabcdef01 /* TR + gdt:limit */ 115 pushl $0xabcdef00 /* CR0 */ 116 117 movl %esp,%ebp 118#define CR0_REGISTER 0(%ebp) 119#define TASK_REGISTER 4(%ebp) 120#define PREVIOUS_GDT 6(%ebp) 121#define PREVIOUS_LDT 12(%ebp) 122#define PREVIOUS_IDT 14(%ebp) 123#define RECOVER_ADDR 20(%ebp) 124#define PHYSICAL_GDT_BASE 24(%ebp) 125#define PREVIOUS_DS 28(%ebp) 126#define PREVIOUS_ES 30(%ebp) 127#define PREVIOUS_FS 32(%ebp) 128#define PREVIOUS_GS 34(%ebp) 129#define PREVIOUS_SS 36(%ebp) 130 131 /* Fixup TSS type field */ 132#define TSS_TYPEFIX_MASK 0xf9 133 xorl %esi,%esi 134 movl PHYSICAL_GDT_BASE,%ebx 135 movw TASK_REGISTER,%si 136 leal (%ebx,%esi),%eax /* get TSS segment descriptor */ 137 andb $TSS_TYPEFIX_MASK,5(%eax) 138 139 /* Prepare to return to sleep/wakeup code point */ 140 lgdt PREVIOUS_GDT 141 lidt PREVIOUS_IDT 142 143 xorl %eax,%eax 144 movl %eax,%ebx 145 movl %eax,%ecx 146 movl %eax,%edx 147 movl %eax,%esi 148 movl %eax,%edi 149 movl PREVIOUS_DS,%ebx 150 movl PREVIOUS_FS,%ecx 151 movl PREVIOUS_SS,%edx 152 movw TASK_REGISTER,%si 153 shll $16,%esi 154 movw PREVIOUS_LDT,%si 155 movl RECOVER_ADDR,%edi 156 157 /* Enable paging and etc. */ 158 movl CR0_REGISTER,%eax 159 movl %eax,%cr0 160 161 /* Flush the prefetch queue */ 162 jmp 1f 1631: jmp 1f 1641: 165 /* 166 * Now that we are in kernel virtual memory addressing 167 * %ebx: ds + es 168 * %ecx: fs + gs 169 * %edx: ss + dummy 170 * %esi: LDTR + TR 171 * %edi: recover address 172 */ 173 174 nop 175 176 movl %esi,%eax /* LDTR + TR */ 177 lldt %ax /* load LDT register */ 178 shrl $16,%eax 179 ltr %ax /* load task register */ 180 181 /* Restore segment registers */ 182 movl %ebx,%eax /* ds + es */ 183 movw %ax,%ds 184 shrl $16,%eax 185 movw %ax,%es 186 movl %ecx,%eax /* fs + gs */ 187 movw %ax,%fs 188 shrl $16,%eax 189 movw %ax,%gs 190 movl %edx,%eax /* ss */ 191 movw %ax,%ss 192 193 /* Jump to acpi_restorecpu() */ 194 jmp *%edi 195 196/* used in real mode */ 197physical_gdt: .word 0 198 .long 0 199physical_esp: .long 0 200previous_cr2: .long 0 201previous_cr3: .long 0 202previous_cr4: .long 0 203 204/* transfer from real mode to protected mode */ 205previous_cr0: .long 0 206previous_tr: .word 0 207previous_gdt: .word 0 208 .long 0 209previous_ldt: .word 0 210previous_idt: .word 0 211 .long 0 212where_to_recover: .long 0 213previous_ds: .word 0 214previous_es: .word 0 215previous_fs: .word 0 216previous_gs: .word 0 217previous_ss: .word 0 218dummy: .word 0 219