summaryrefslogtreecommitdiffstats
path: root/arch/i386/kernel/acpi/wakeup.S
blob: 7c74fe0dc93c17b8a8bbb3483d0da623589d2449 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
.text
#include <linux/linkage.h>
#include <asm/segment.h>
#include <asm/page.h>

#
# wakeup_code runs in real mode, and at unknown address (determined at run-time).
# Therefore it must only use relative jumps/calls. 
#
# Do we need to deal with A20? It is okay: ACPI specs says A20 must be enabled
#
# If physical address of wakeup_code is 0x12345, BIOS should call us with
# cs = 0x1234, eip = 0x05
# 

ALIGN
	.align	4096
ENTRY(wakeup_start)
wakeup_code:
	wakeup_code_start = .
	.code16

 	movw	$0xb800, %ax
	movw	%ax,%fs
	movw	$0x0e00 + 'L', %fs:(0x10)

	cli
	cld

	# setup data segment
	movw	%cs, %ax
	movw	%ax, %ds					# Make ds:0 point to wakeup_start
	movw	%ax, %ss
	mov	$(wakeup_stack - wakeup_code), %sp		# Private stack is needed for ASUS board
	movw	$0x0e00 + 'S', %fs:(0x12)

	pushl	$0						# Kill any dangerous flags
	popfl

	movl	real_magic - wakeup_code, %eax
	cmpl	$0x12345678, %eax
	jne	bogus_real_magic

	testl	$1, video_flags - wakeup_code
	jz	1f
	lcall   $0xc000,$3
	movw	%cs, %ax
	movw	%ax, %ds					# Bios might have played with that
	movw	%ax, %ss
1:

	testl	$2, video_flags - wakeup_code
	jz	1f
	mov	video_mode - wakeup_code, %ax
	call	mode_set
1:

	# set up page table
	movl	$swapper_pg_dir-__PAGE_OFFSET, %eax
	movl	%eax, %cr3

	testl	$1, real_efer_save_restore - wakeup_code
	jz	4f
	# restore efer setting
	movl	real_save_efer_edx - wakeup_code, %edx
	movl	real_save_efer_eax - wakeup_code, %eax
	mov     $0xc0000080, %ecx
	wrmsr
4:
	# make sure %cr4 is set correctly (features, etc)
	movl	real_save_cr4 - wakeup_code, %eax
	movl	%eax, %cr4
	movw	$0xb800, %ax
	movw	%ax,%fs
	movw	$0x0e00 + 'i', %fs:(0x12)
	
	# need a gdt -- use lgdtl to force 32-bit operands, in case
	# the GDT is located past 16 megabytes.
	lgdtl	real_save_gdt - wakeup_code

	movl	real_save_cr0 - wakeup_code, %eax
	movl	%eax, %cr0
	jmp 1f
1:
	movw	$0x0e00 + 'n', %fs:(0x14)

	movl	real_magic - wakeup_code, %eax
	cmpl	$0x12345678, %eax
	jne	bogus_real_magic

	ljmpl	$__KERNEL_CS,$wakeup_pmode_return

real_save_gdt:	.word 0
		.long 0
real_save_cr0:	.long 0
real_save_cr3:	.long 0
real_save_cr4:	.long 0
real_magic:	.long 0
video_mode:	.long 0
video_flags:	.long 0
real_efer_save_restore:	.long 0
real_save_efer_edx: 	.long 0
real_save_efer_eax: 	.long 0

bogus_real_magic:
	movw	$0x0e00 + 'B', %fs:(0x12)
	jmp bogus_real_magic

/* This code uses an extended set of video mode numbers. These include:
 * Aliases for standard modes
 *	NORMAL_VGA (-1)
 *	EXTENDED_VGA (-2)
 *	ASK_VGA (-3)
 * Video modes numbered by menu position -- NOT RECOMMENDED because of lack
 * of compatibility when extending the table. These are between 0x00 and 0xff.
 */
#define VIDEO_FIRST_MENU 0x0000

/* Standard BIOS video modes (BIOS number + 0x0100) */
#define VIDEO_FIRST_BIOS 0x0100

/* VESA BIOS video modes (VESA number + 0x0200) */
#define VIDEO_FIRST_VESA 0x0200

/* Video7 special modes (BIOS number + 0x0900) */
#define VIDEO_FIRST_V7 0x0900

# Setting of user mode (AX=mode ID) => CF=success
mode_set:
	movw	%ax, %bx
#if 0
	cmpb	$0xff, %ah
	jz	setalias

	testb	$VIDEO_RECALC>>8, %ah
	jnz	_setrec

	cmpb	$VIDEO_FIRST_RESOLUTION>>8, %ah
	jnc	setres
	
	cmpb	$VIDEO_FIRST_SPECIAL>>8, %ah
	jz	setspc

	cmpb	$VIDEO_FIRST_V7>>8, %ah
	jz	setv7
#endif
	
	cmpb	$VIDEO_FIRST_VESA>>8, %ah
	jnc	check_vesa
#if 0	
	orb	%ah, %ah
	jz	setmenu
#endif
	
	decb	%ah
#	jz	setbios				  Add bios modes later

setbad:	clc
	ret

check_vesa:
	subb	$VIDEO_FIRST_VESA>>8, %bh
	orw	$0x4000, %bx			# Use linear frame buffer
	movw	$0x4f02, %ax			# VESA BIOS mode set call
	int	$0x10
	cmpw	$0x004f, %ax			# AL=4f if implemented
	jnz	_setbad				# AH=0 if OK

	stc
	ret

_setbad: jmp setbad

	.code32
	ALIGN

.org	0x800
wakeup_stack_begin:	# Stack grows down

.org	0xff0		# Just below end of page
wakeup_stack:
ENTRY(wakeup_end)
	
.org	0x1000

wakeup_pmode_return:
	movw	$__KERNEL_DS, %ax
	movw	%ax, %ss
	movw	%ax, %ds
	movw	%ax, %es
	movw	%ax, %fs
	movw	%ax, %gs
	movw	$0x0e00 + 'u', 0xb8016

	# reload the gdt, as we need the full 32 bit address
	lgdt	saved_gdt
	lidt	saved_idt
	lldt	saved_ldt
	ljmp	$(__KERNEL_CS),$1f
1:
	movl	%cr3, %eax
	movl	%eax, %cr3
	wbinvd

	# and restore the stack ... but you need gdt for this to work
	movl	saved_context_esp, %esp

	movl	%cs:saved_magic, %eax
	cmpl	$0x12345678, %eax
	jne	bogus_magic

	# jump to place where we left off
	movl	saved_eip,%eax
	jmp	*%eax

bogus_magic:
	movw	$0x0e00 + 'B', 0xb8018
	jmp	bogus_magic


##
# acpi_copy_wakeup_routine
#
# Copy the above routine to low memory.
#
# Parameters:
# %eax:	place to copy wakeup routine to
#
# Returned address is location of code in low memory (past data and stack)
#
ENTRY(acpi_copy_wakeup_routine)

	sgdt	saved_gdt
	sidt	saved_idt
	sldt	saved_ldt
	str	saved_tss

	movl	nx_enabled, %edx
	movl	%edx, real_efer_save_restore - wakeup_start (%eax)
	testl	$1, real_efer_save_restore - wakeup_start (%eax)
	jz	2f
	# save efer setting
	pushl	%eax
	movl	%eax, %ebx
	mov     $0xc0000080, %ecx
	rdmsr
	movl	%edx, real_save_efer_edx - wakeup_start (%ebx)
	movl	%eax, real_save_efer_eax - wakeup_start (%ebx)
	popl	%eax
2:

	movl    %cr3, %edx
	movl    %edx, real_save_cr3 - wakeup_start (%eax)
	movl    %cr4, %edx
	movl    %edx, real_save_cr4 - wakeup_start (%eax)
	movl	%cr0, %edx
	movl	%edx, real_save_cr0 - wakeup_start (%eax)
	sgdt    real_save_gdt - wakeup_start (%eax)

	movl	saved_videomode, %edx
	movl	%edx, video_mode - wakeup_start (%eax)
	movl	acpi_video_flags, %edx
	movl	%edx, video_flags - wakeup_start (%eax)
	movl	$0x12345678, real_magic - wakeup_start (%eax)
	movl	$0x12345678, saved_magic
	ret

.data
ALIGN
ENTRY(saved_magic)	.long	0
ENTRY(saved_eip)	.long	0

save_registers:
	leal	4(%esp), %eax
	movl	%eax, saved_context_esp
	movl %ebx, saved_context_ebx
	movl %ebp, saved_context_ebp
	movl %esi, saved_context_esi
	movl %edi, saved_context_edi
	pushfl ; popl saved_context_eflags

	movl $ret_point, saved_eip
	ret


restore_registers:
	movl saved_context_ebp, %ebp
	movl saved_context_ebx, %ebx
	movl saved_context_esi, %esi
	movl saved_context_edi, %edi
	pushl saved_context_eflags ; popfl
	ret	

ENTRY(do_suspend_lowlevel)
	call	save_processor_state
	call	save_registers
	pushl	$3
	call	acpi_enter_sleep_state
	addl	$4, %esp
	ret
	.p2align 4,,7
ret_point:
	call	restore_registers
	call	restore_processor_state
	ret

ALIGN
# saved registers
saved_gdt:	.long	0,0
saved_idt:	.long	0,0
saved_ldt:	.long	0
saved_tss:	.long	0

OpenPOWER on IntegriCloud