1/*- 2 * Copyright (c) 2001 Takanori Watanabe <takawata@jp.freebsd.org> 3 * Copyright (c) 2001-2012 Mitsuru IWASAKI <iwasaki@jp.freebsd.org> 4 * Copyright (c) 2003 Peter Wemm 5 * Copyright (c) 2008-2012 Jung-uk Kim <jkim@FreeBSD.org> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 * 29 * $FreeBSD$ 30 */ 31 32#include <machine/asmacros.h> 33#include <machine/specialreg.h> 34#include <x86/ppireg.h> 35#include <x86/timerreg.h> 36 37#include "assym.inc" 38 39/* 40 * Resume entry point. The BIOS enters here in real mode after POST with 41 * CS set to the page where we stored this code. It should configure the 42 * segment registers with a flat 4 GB address space and EFLAGS.IF = 0. 43 * Depending on the previous sleep state, we may need to initialize more 44 * of the system (i.e., S3 suspend-to-RAM vs. S4 suspend-to-disk). 45 */ 46 47 .data /* So we can modify it */ 48 49 ALIGN_TEXT 50 .code16 51wakeup_start: 52 /* 53 * Set up segment registers for real mode and a small stack for 54 * any calls we make. Set up full 32-bit bootstrap kernel flags 55 * since resumectx() doesn't restore flags. PSL_KERNEL gives 56 * bootstrap kernel flags (with interrupts disabled), not normal 57 * kernel flags. 58 */ 59 cli /* make sure no interrupts */ 60 mov %cs, %ax /* copy %cs to %ds. Remember these */ 61 mov %ax, %ds /* are offsets rather than selectors */ 62 mov %ax, %ss 63 movw $PAGE_SIZE, %sp 64 pushl $PSL_KERNEL 65 popfl 66 67 /* To debug resume hangs, beep the speaker if the user requested. */ 68 testb $~0, resume_beep - wakeup_start 69 jz 1f 70 movb $0, resume_beep - wakeup_start 71 72 /* Set PIC timer2 to beep. */ 73 movb $(TIMER_SEL2 | TIMER_SQWAVE | TIMER_16BIT), %al 74 outb %al, $TIMER_MODE 75 76 /* Turn on speaker. */ 77 inb $IO_PPI, %al 78 orb $PIT_SPKR, %al 79 outb %al, $IO_PPI 80 81 /* Set frequency. */ 82 movw $0x4c0, %ax 83 outb %al, $TIMER_CNTR2 84 shrw $8, %ax 85 outb %al, $TIMER_CNTR2 861: 87 88 /* Re-initialize video BIOS if the reset_video tunable is set. */ 89 testb $~0, reset_video - wakeup_start 90 jz 1f 91 movb $0, reset_video - wakeup_start 92 lcall $0xc000, $3 93 94 /* When we reach here, int 0x10 should be ready. Hide cursor. */ 95 movb $0x01, %ah 96 movb $0x20, %ch 97 int $0x10 98 99 /* Re-start in case the previous BIOS call clobbers them. */ 100 jmp wakeup_start 1011: 102 103 /* 104 * Find relocation base and patch the gdt descript and ljmp targets 105 */ 106 xorl %ebx, %ebx 107 mov %cs, %bx 108 sall $4, %ebx /* %ebx is now our relocation base */ 109 110 /* 111 * Load the descriptor table pointer. We'll need it when running 112 * in 16-bit protected mode. 113 */ 114 lgdtl bootgdtdesc - wakeup_start 115 116 /* Enable protected mode */ 117 movl $CR0_PE, %eax 118 mov %eax, %cr0 119 120 /* 121 * Now execute a far jump to turn on protected mode. This 122 * causes the segment registers to turn into selectors and causes 123 * %cs to be loaded from the gdt. 124 * 125 * The following instruction is: 126 * ljmpl $bootcode32 - bootgdt, $wakeup_32 - wakeup_start 127 * but gas cannot assemble that. And besides, we patch the targets 128 * in early startup and its a little clearer what we are patching. 129 */ 130wakeup_sw32: 131 .byte 0x66 /* size override to 32 bits */ 132 .byte 0xea /* opcode for far jump */ 133 .long wakeup_32 - wakeup_start /* offset in segment */ 134 .word bootcode32 - bootgdt /* index in gdt for 32 bit code */ 135 136 /* 137 * At this point, we are running in 32 bit legacy protected mode. 138 */ 139 ALIGN_TEXT 140 .code32 141wakeup_32: 142 143 mov $bootdata32 - bootgdt, %eax 144 mov %ax, %ds 145 146 /* Restore EFER, CR4 and CR3. */ 147 movl wakeup_efer - wakeup_start(%ebx), %eax 148 movl wakeup_efer - wakeup_start + 4(%ebx), %edx 149 cmpl $0, %eax 150 jne 1f 151 cmpl $0, %edx 152 je 2f 1531: movl $MSR_EFER, %ecx 154 wrmsr 1552: movl wakeup_cr4 - wakeup_start(%ebx), %eax 156 cmpl $0, %eax 157 je 3f 158 mov %eax, %cr4 1593: movl wakeup_cr3 - wakeup_start(%ebx), %eax 160 mov %eax, %cr3 161 162 /* Get PCB and return address. */ 163 movl wakeup_ret - wakeup_start(%ebx), %edx 164 movl wakeup_pcb - wakeup_start(%ebx), %ecx 165 166 /* Enable paging. */ 167 mov %cr0, %eax 168 orl $CR0_PG, %eax 169 mov %eax, %cr0 170 171 /* Jump to return address. */ 172 jmp *%edx 173 174 .data 175 176resume_beep: 177 .byte 0 178reset_video: 179 .byte 0 180 181 ALIGN_DATA 182bootgdt: 183 .long 0x00000000 184 .long 0x00000000 185 186bootcode32: 187 .long 0x0000ffff 188 .long 0x00cf9b00 189 190bootdata32: 191 .long 0x0000ffff 192 .long 0x00cf9300 193bootgdtend: 194 195bootgdtdesc: 196 .word bootgdtend - bootgdt /* Length */ 197 .long bootgdt - wakeup_start /* Offset plus %ds << 4 */ 198 199 ALIGN_DATA 200wakeup_efer: 201 .long 0 202 .long 0 203wakeup_cr4: 204 .long 0 205wakeup_cr3: 206 .long 0 207wakeup_pcb: 208 .long 0 209wakeup_ret: 210 .long 0 211wakeup_gdt: /* not used */ 212 .word 0 213 .long 0 214dummy: 215