xref: /linux/arch/x86/kernel/acpi/wakeup_64.S (revision 2b8232ce512105e28453f301d1510de8363bccd1) 
1.text
2#include <linux/linkage.h>
3#include <asm/segment.h>
4#include <asm/pgtable.h>
5#include <asm/page.h>
6#include <asm/msr.h>
7
8# Copyright 2003 Pavel Machek <pavel@suse.cz>, distribute under GPLv2
9#
10# wakeup_code runs in real mode, and at unknown address (determined at run-time).
11# Therefore it must only use relative jumps/calls.
12#
13# Do we need to deal with A20? It is okay: ACPI specs says A20 must be enabled
14#
15# If physical address of wakeup_code is 0x12345, BIOS should call us with
16# cs = 0x1234, eip = 0x05
17#
18
19#define BEEP \
20	inb	$97, %al; 	\
21	outb	%al, $0x80; 	\
22	movb	$3, %al; 	\
23	outb	%al, $97; 	\
24	outb	%al, $0x80; 	\
25	movb	$-74, %al; 	\
26	outb	%al, $67; 	\
27	outb	%al, $0x80; 	\
28	movb	$-119, %al; 	\
29	outb	%al, $66; 	\
30	outb	%al, $0x80; 	\
31	movb	$15, %al; 	\
32	outb	%al, $66;
33
34
35ALIGN
36	.align	16
37ENTRY(wakeup_start)
38wakeup_code:
39	wakeup_code_start = .
40	.code16
41
42# Running in *copy* of this code, somewhere in low 1MB.
43
44	movb	$0xa1, %al	;  outb %al, $0x80
45	cli
46	cld
47	# setup data segment
48	movw	%cs, %ax
49	movw	%ax, %ds		# Make ds:0 point to wakeup_start
50	movw	%ax, %ss
51
52	# Data segment must be set up before we can see whether to beep.
53	testl   $4, realmode_flags - wakeup_code
54	jz      1f
55	BEEP
561:
57
58					# Private stack is needed for ASUS board
59	mov	$(wakeup_stack - wakeup_code), %sp
60
61	pushl	$0			# Kill any dangerous flags
62	popfl
63
64	movl	real_magic - wakeup_code, %eax
65	cmpl	$0x12345678, %eax
66	jne	bogus_real_magic
67
68  	call	verify_cpu			# Verify the cpu supports long
69						# mode
70	testl	%eax, %eax
71	jnz	no_longmode
72
73	testl	$1, realmode_flags - wakeup_code
74	jz	1f
75	lcall   $0xc000,$3
76	movw	%cs, %ax
77	movw	%ax, %ds		# Bios might have played with that
78	movw	%ax, %ss
791:
80
81	testl	$2, realmode_flags - wakeup_code
82	jz	1f
83	mov	video_mode - wakeup_code, %ax
84	call	mode_set
851:
86
87 	movw	$0xb800, %ax
88	movw	%ax,%fs
89	movw	$0x0e00 + 'L', %fs:(0x10)
90
91	movb	$0xa2, %al	;  outb %al, $0x80
92
93	mov	%ds, %ax			# Find 32bit wakeup_code addr
94	movzx   %ax, %esi			# (Convert %ds:gdt to a liner ptr)
95	shll    $4, %esi
96						# Fix up the vectors
97	addl    %esi, wakeup_32_vector - wakeup_code
98	addl    %esi, wakeup_long64_vector - wakeup_code
99	addl    %esi, gdt_48a + 2 - wakeup_code # Fixup the gdt pointer
100
101	lidtl	%ds:idt_48a - wakeup_code
102	lgdtl	%ds:gdt_48a - wakeup_code	# load gdt with whatever is
103						# appropriate
104
105	movl	$1, %eax			# protected mode (PE) bit
106	lmsw	%ax				# This is it!
107	jmp	1f
1081:
109
110	ljmpl   *(wakeup_32_vector - wakeup_code)
111
112	.balign 4
113wakeup_32_vector:
114	.long   wakeup_32 - wakeup_code
115	.word   __KERNEL32_CS, 0
116
117	.code32
118wakeup_32:
119# Running in this code, but at low address; paging is not yet turned on.
120	movb	$0xa5, %al	;  outb %al, $0x80
121
122	movl	$__KERNEL_DS, %eax
123	movl	%eax, %ds
124
125	movw	$0x0e00 + 'i', %ds:(0xb8012)
126	movb	$0xa8, %al	;  outb %al, $0x80;
127
128	/*
129	 * Prepare for entering 64bits mode
130	 */
131
132	/* Enable PAE */
133	xorl	%eax, %eax
134	btsl	$5, %eax
135	movl	%eax, %cr4
136
137	/* Setup early boot stage 4 level pagetables */
138	leal    (wakeup_level4_pgt - wakeup_code)(%esi), %eax
139	movl	%eax, %cr3
140
141        /* Check if nx is implemented */
142        movl    $0x80000001, %eax
143        cpuid
144        movl    %edx,%edi
145
146	/* Enable Long Mode */
147	xorl    %eax, %eax
148	btsl	$_EFER_LME, %eax
149
150	/* No Execute supported? */
151	btl	$20,%edi
152	jnc     1f
153	btsl	$_EFER_NX, %eax
154
155	/* Make changes effective */
1561:	movl    $MSR_EFER, %ecx
157	xorl    %edx, %edx
158	wrmsr
159
160	xorl	%eax, %eax
161	btsl	$31, %eax			/* Enable paging and in turn activate Long Mode */
162	btsl	$0, %eax			/* Enable protected mode */
163
164	/* Make changes effective */
165	movl	%eax, %cr0
166
167	/* At this point:
168		CR4.PAE must be 1
169		CS.L must be 0
170		CR3 must point to PML4
171		Next instruction must be a branch
172		This must be on identity-mapped page
173	*/
174	/*
175	 * At this point we're in long mode but in 32bit compatibility mode
176	 * with EFER.LME = 1, CS.L = 0, CS.D = 1 (and in turn
177	 * EFER.LMA = 1). Now we want to jump in 64bit mode, to do that we load
178	 * the new gdt/idt that has __KERNEL_CS with CS.L = 1.
179	 */
180
181	/* Finally jump in 64bit mode */
182        ljmp    *(wakeup_long64_vector - wakeup_code)(%esi)
183
184	.balign 4
185wakeup_long64_vector:
186	.long   wakeup_long64 - wakeup_code
187	.word   __KERNEL_CS, 0
188
189.code64
190
191	/* Hooray, we are in Long 64-bit mode (but still running in
192	 * low memory)
193	 */
194wakeup_long64:
195	/*
196	 * We must switch to a new descriptor in kernel space for the GDT
197	 * because soon the kernel won't have access anymore to the userspace
198	 * addresses where we're currently running on. We have to do that here
199	 * because in 32bit we couldn't load a 64bit linear address.
200	 */
201	lgdt	cpu_gdt_descr
202
203	movw	$0x0e00 + 'n', %ds:(0xb8014)
204	movb	$0xa9, %al	;  outb %al, $0x80
205
206	movq    saved_magic, %rax
207	movq    $0x123456789abcdef0, %rdx
208	cmpq    %rdx, %rax
209	jne     bogus_64_magic
210
211	movw	$0x0e00 + 'u', %ds:(0xb8016)
212
213	nop
214	nop
215	movw	$__KERNEL_DS, %ax
216	movw	%ax, %ss
217	movw	%ax, %ds
218	movw	%ax, %es
219	movw	%ax, %fs
220	movw	%ax, %gs
221	movq	saved_rsp, %rsp
222
223	movw	$0x0e00 + 'x', %ds:(0xb8018)
224	movq	saved_rbx, %rbx
225	movq	saved_rdi, %rdi
226	movq	saved_rsi, %rsi
227	movq	saved_rbp, %rbp
228
229	movw	$0x0e00 + '!', %ds:(0xb801a)
230	movq	saved_rip, %rax
231	jmp	*%rax
232
233.code32
234
235	.align	64
236gdta:
237	/* Its good to keep gdt in sync with one in trampoline.S */
238	.word	0, 0, 0, 0			# dummy
239	/* ??? Why I need the accessed bit set in order for this to work? */
240	.quad   0x00cf9b000000ffff              # __KERNEL32_CS
241	.quad   0x00af9b000000ffff              # __KERNEL_CS
242	.quad   0x00cf93000000ffff              # __KERNEL_DS
243
244idt_48a:
245	.word	0				# idt limit = 0
246	.word	0, 0				# idt base = 0L
247
248gdt_48a:
249	.word	0x800				# gdt limit=2048,
250						#  256 GDT entries
251	.long   gdta - wakeup_code              # gdt base (relocated in later)
252
253real_magic:	.quad 0
254video_mode:	.quad 0
255realmode_flags:	.quad 0
256
257.code16
258bogus_real_magic:
259	movb	$0xba,%al	;  outb %al,$0x80
260	jmp bogus_real_magic
261
262.code64
263bogus_64_magic:
264	movb	$0xb3,%al	;  outb %al,$0x80
265	jmp bogus_64_magic
266
267.code16
268no_longmode:
269	movb    $0xbc,%al       ;  outb %al,$0x80
270	jmp no_longmode
271
272#include "../verify_cpu_64.S"
273
274/* This code uses an extended set of video mode numbers. These include:
275 * Aliases for standard modes
276 *	NORMAL_VGA (-1)
277 *	EXTENDED_VGA (-2)
278 *	ASK_VGA (-3)
279 * Video modes numbered by menu position -- NOT RECOMMENDED because of lack
280 * of compatibility when extending the table. These are between 0x00 and 0xff.
281 */
282#define VIDEO_FIRST_MENU 0x0000
283
284/* Standard BIOS video modes (BIOS number + 0x0100) */
285#define VIDEO_FIRST_BIOS 0x0100
286
287/* VESA BIOS video modes (VESA number + 0x0200) */
288#define VIDEO_FIRST_VESA 0x0200
289
290/* Video7 special modes (BIOS number + 0x0900) */
291#define VIDEO_FIRST_V7 0x0900
292
293# Setting of user mode (AX=mode ID) => CF=success
294
295# For now, we only handle VESA modes (0x0200..0x03ff).  To handle other
296# modes, we should probably compile in the video code from the boot
297# directory.
298.code16
299mode_set:
300	movw	%ax, %bx
301	subb	$VIDEO_FIRST_VESA>>8, %bh
302	cmpb	$2, %bh
303	jb	check_vesa
304
305setbad:
306	clc
307	ret
308
309check_vesa:
310	orw	$0x4000, %bx			# Use linear frame buffer
311	movw	$0x4f02, %ax			# VESA BIOS mode set call
312	int	$0x10
313	cmpw	$0x004f, %ax			# AL=4f if implemented
314	jnz	setbad				# AH=0 if OK
315
316	stc
317	ret
318
319wakeup_stack_begin:	# Stack grows down
320
321.org	0xff0
322wakeup_stack:		# Just below end of page
323
324.org   0x1000
325ENTRY(wakeup_level4_pgt)
326	.quad   level3_ident_pgt - __START_KERNEL_map + _KERNPG_TABLE
327	.fill   510,8,0
328	/* (2^48-(2*1024*1024*1024))/(2^39) = 511 */
329	.quad   level3_kernel_pgt - __START_KERNEL_map + _KERNPG_TABLE
330
331ENTRY(wakeup_end)
332
333##
334# acpi_copy_wakeup_routine
335#
336# Copy the above routine to low memory.
337#
338# Parameters:
339# %rdi:	place to copy wakeup routine to
340#
341# Returned address is location of code in low memory (past data and stack)
342#
343	.code64
344ENTRY(acpi_copy_wakeup_routine)
345	pushq	%rax
346	pushq	%rdx
347
348	movl	saved_video_mode, %edx
349	movl	%edx, video_mode - wakeup_start (,%rdi)
350	movl	acpi_realmode_flags, %edx
351	movl	%edx, realmode_flags - wakeup_start (,%rdi)
352	movq	$0x12345678, real_magic - wakeup_start (,%rdi)
353	movq	$0x123456789abcdef0, %rdx
354	movq	%rdx, saved_magic
355
356	movq    saved_magic, %rax
357	movq    $0x123456789abcdef0, %rdx
358	cmpq    %rdx, %rax
359	jne     bogus_64_magic
360
361	# restore the regs we used
362	popq	%rdx
363	popq	%rax
364ENTRY(do_suspend_lowlevel_s4bios)
365	ret
366
367	.align 2
368	.p2align 4,,15
369.globl do_suspend_lowlevel
370	.type	do_suspend_lowlevel,@function
371do_suspend_lowlevel:
372.LFB5:
373	subq	$8, %rsp
374	xorl	%eax, %eax
375	call	save_processor_state
376
377	movq %rsp, saved_context_esp(%rip)
378	movq %rax, saved_context_eax(%rip)
379	movq %rbx, saved_context_ebx(%rip)
380	movq %rcx, saved_context_ecx(%rip)
381	movq %rdx, saved_context_edx(%rip)
382	movq %rbp, saved_context_ebp(%rip)
383	movq %rsi, saved_context_esi(%rip)
384	movq %rdi, saved_context_edi(%rip)
385	movq %r8,  saved_context_r08(%rip)
386	movq %r9,  saved_context_r09(%rip)
387	movq %r10, saved_context_r10(%rip)
388	movq %r11, saved_context_r11(%rip)
389	movq %r12, saved_context_r12(%rip)
390	movq %r13, saved_context_r13(%rip)
391	movq %r14, saved_context_r14(%rip)
392	movq %r15, saved_context_r15(%rip)
393	pushfq ; popq saved_context_eflags(%rip)
394
395	movq	$.L97, saved_rip(%rip)
396
397	movq %rsp,saved_rsp
398	movq %rbp,saved_rbp
399	movq %rbx,saved_rbx
400	movq %rdi,saved_rdi
401	movq %rsi,saved_rsi
402
403	addq	$8, %rsp
404	movl	$3, %edi
405	xorl	%eax, %eax
406	jmp	acpi_enter_sleep_state
407.L97:
408	.p2align 4,,7
409.L99:
410	.align 4
411	movl	$24, %eax
412	movw %ax, %ds
413	movq	saved_context+58(%rip), %rax
414	movq %rax, %cr4
415	movq	saved_context+50(%rip), %rax
416	movq %rax, %cr3
417	movq	saved_context+42(%rip), %rax
418	movq %rax, %cr2
419	movq	saved_context+34(%rip), %rax
420	movq %rax, %cr0
421	pushq saved_context_eflags(%rip) ; popfq
422	movq saved_context_esp(%rip), %rsp
423	movq saved_context_ebp(%rip), %rbp
424	movq saved_context_eax(%rip), %rax
425	movq saved_context_ebx(%rip), %rbx
426	movq saved_context_ecx(%rip), %rcx
427	movq saved_context_edx(%rip), %rdx
428	movq saved_context_esi(%rip), %rsi
429	movq saved_context_edi(%rip), %rdi
430	movq saved_context_r08(%rip), %r8
431	movq saved_context_r09(%rip), %r9
432	movq saved_context_r10(%rip), %r10
433	movq saved_context_r11(%rip), %r11
434	movq saved_context_r12(%rip), %r12
435	movq saved_context_r13(%rip), %r13
436	movq saved_context_r14(%rip), %r14
437	movq saved_context_r15(%rip), %r15
438
439	xorl	%eax, %eax
440	addq	$8, %rsp
441	jmp	restore_processor_state
442.LFE5:
443.Lfe5:
444	.size	do_suspend_lowlevel,.Lfe5-do_suspend_lowlevel
445
446.data
447ALIGN
448ENTRY(saved_rbp)	.quad	0
449ENTRY(saved_rsi)	.quad	0
450ENTRY(saved_rdi)	.quad	0
451ENTRY(saved_rbx)	.quad	0
452
453ENTRY(saved_rip)	.quad	0
454ENTRY(saved_rsp)	.quad	0
455
456ENTRY(saved_magic)	.quad	0
457