diff options
Diffstat (limited to 'arch/x86/platform/olpc/xo1-wakeup.S')
-rw-r--r-- | arch/x86/platform/olpc/xo1-wakeup.S | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/arch/x86/platform/olpc/xo1-wakeup.S b/arch/x86/platform/olpc/xo1-wakeup.S new file mode 100644 index 00000000000..948deb28975 --- /dev/null +++ b/arch/x86/platform/olpc/xo1-wakeup.S | |||
@@ -0,0 +1,124 @@ | |||
1 | .text | ||
2 | #include <linux/linkage.h> | ||
3 | #include <asm/segment.h> | ||
4 | #include <asm/page.h> | ||
5 | #include <asm/pgtable_32.h> | ||
6 | |||
7 | .macro writepost,value | ||
8 | movb $0x34, %al | ||
9 | outb %al, $0x70 | ||
10 | movb $\value, %al | ||
11 | outb %al, $0x71 | ||
12 | .endm | ||
13 | |||
14 | wakeup_start: | ||
15 | # OFW lands us here, running in protected mode, with a | ||
16 | # kernel-compatible GDT already setup. | ||
17 | |||
18 | # Clear any dangerous flags | ||
19 | pushl $0 | ||
20 | popfl | ||
21 | |||
22 | writepost 0x31 | ||
23 | |||
24 | # Set up %cr3 | ||
25 | movl $initial_page_table - __PAGE_OFFSET, %eax | ||
26 | movl %eax, %cr3 | ||
27 | |||
28 | movl saved_cr4, %eax | ||
29 | movl %eax, %cr4 | ||
30 | |||
31 | movl saved_cr0, %eax | ||
32 | movl %eax, %cr0 | ||
33 | |||
34 | # Control registers were modified, pipeline resync is needed | ||
35 | jmp 1f | ||
36 | 1: | ||
37 | |||
38 | movw $__KERNEL_DS, %ax | ||
39 | movw %ax, %ss | ||
40 | movw %ax, %ds | ||
41 | movw %ax, %es | ||
42 | movw %ax, %fs | ||
43 | movw %ax, %gs | ||
44 | |||
45 | lgdt saved_gdt | ||
46 | lidt saved_idt | ||
47 | lldt saved_ldt | ||
48 | ljmp $(__KERNEL_CS),$1f | ||
49 | 1: | ||
50 | movl %cr3, %eax | ||
51 | movl %eax, %cr3 | ||
52 | wbinvd | ||
53 | |||
54 | # Go back to the return point | ||
55 | jmp ret_point | ||
56 | |||
57 | save_registers: | ||
58 | sgdt saved_gdt | ||
59 | sidt saved_idt | ||
60 | sldt saved_ldt | ||
61 | |||
62 | pushl %edx | ||
63 | movl %cr4, %edx | ||
64 | movl %edx, saved_cr4 | ||
65 | |||
66 | movl %cr0, %edx | ||
67 | movl %edx, saved_cr0 | ||
68 | |||
69 | popl %edx | ||
70 | |||
71 | movl %ebx, saved_context_ebx | ||
72 | movl %ebp, saved_context_ebp | ||
73 | movl %esi, saved_context_esi | ||
74 | movl %edi, saved_context_edi | ||
75 | |||
76 | pushfl | ||
77 | popl saved_context_eflags | ||
78 | |||
79 | ret | ||
80 | |||
81 | restore_registers: | ||
82 | movl saved_context_ebp, %ebp | ||
83 | movl saved_context_ebx, %ebx | ||
84 | movl saved_context_esi, %esi | ||
85 | movl saved_context_edi, %edi | ||
86 | |||
87 | pushl saved_context_eflags | ||
88 | popfl | ||
89 | |||
90 | ret | ||
91 | |||
92 | ENTRY(do_olpc_suspend_lowlevel) | ||
93 | call save_processor_state | ||
94 | call save_registers | ||
95 | |||
96 | # This is the stack context we want to remember | ||
97 | movl %esp, saved_context_esp | ||
98 | |||
99 | pushl $3 | ||
100 | call xo1_do_sleep | ||
101 | |||
102 | jmp wakeup_start | ||
103 | .p2align 4,,7 | ||
104 | ret_point: | ||
105 | movl saved_context_esp, %esp | ||
106 | |||
107 | writepost 0x32 | ||
108 | |||
109 | call restore_registers | ||
110 | call restore_processor_state | ||
111 | ret | ||
112 | |||
113 | .data | ||
114 | saved_gdt: .long 0,0 | ||
115 | saved_idt: .long 0,0 | ||
116 | saved_ldt: .long 0 | ||
117 | saved_cr4: .long 0 | ||
118 | saved_cr0: .long 0 | ||
119 | saved_context_esp: .long 0 | ||
120 | saved_context_edi: .long 0 | ||
121 | saved_context_esi: .long 0 | ||
122 | saved_context_ebx: .long 0 | ||
123 | saved_context_ebp: .long 0 | ||
124 | saved_context_eflags: .long 0 | ||