2 * Suspend support specific for i386.
4 * Distribute under GPLv2
6 * Copyright (c) 2002 Pavel Machek <pavel@suse.cz>
7 * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
10 #include <linux/module.h>
11 #include <linux/suspend.h>
16 static struct saved_context saved_context
;
18 unsigned long saved_context_ebx
;
19 unsigned long saved_context_esp
, saved_context_ebp
;
20 unsigned long saved_context_esi
, saved_context_edi
;
21 unsigned long saved_context_eflags
;
23 static void __save_processor_state(struct saved_context
*ctxt
)
25 mtrr_save_fixed_ranges(NULL
);
31 store_gdt(&ctxt
->gdt
);
32 store_idt(&ctxt
->idt
);
38 savesegment(es
, ctxt
->es
);
39 savesegment(fs
, ctxt
->fs
);
40 savesegment(gs
, ctxt
->gs
);
41 savesegment(ss
, ctxt
->ss
);
46 ctxt
->cr0
= read_cr0();
47 ctxt
->cr2
= read_cr2();
48 ctxt
->cr3
= read_cr3();
49 ctxt
->cr4
= read_cr4_safe();
53 void save_processor_state(void)
55 __save_processor_state(&saved_context
);
57 EXPORT_SYMBOL(save_processor_state
);
59 static void do_fpu_end(void)
62 * Restore FPU regs if necessary.
67 static void fix_processor_context(void)
69 int cpu
= smp_processor_id();
70 struct tss_struct
*t
= &per_cpu(init_tss
, cpu
);
72 set_tss_desc(cpu
, t
); /*
73 * This just modifies memory; should not be
74 * necessary. But... This is necessary, because
75 * 386 hardware has concept of busy TSS or some
79 load_TR_desc(); /* This does ltr */
80 load_LDT(¤t
->active_mm
->context
); /* This does lldt */
83 * Now maybe reload the debug registers
85 if (current
->thread
.debugreg7
) {
86 set_debugreg(current
->thread
.debugreg0
, 0);
87 set_debugreg(current
->thread
.debugreg1
, 1);
88 set_debugreg(current
->thread
.debugreg2
, 2);
89 set_debugreg(current
->thread
.debugreg3
, 3);
91 set_debugreg(current
->thread
.debugreg6
, 6);
92 set_debugreg(current
->thread
.debugreg7
, 7);
97 static void __restore_processor_state(struct saved_context
*ctxt
)
102 /* cr4 was introduced in the Pentium CPU */
104 write_cr4(ctxt
->cr4
);
105 write_cr3(ctxt
->cr3
);
106 write_cr2(ctxt
->cr2
);
107 write_cr0(ctxt
->cr0
);
110 * now restore the descriptor tables to their proper values
111 * ltr is done i fix_processor_context().
113 load_gdt(&ctxt
->gdt
);
114 load_idt(&ctxt
->idt
);
119 loadsegment(es
, ctxt
->es
);
120 loadsegment(fs
, ctxt
->fs
);
121 loadsegment(gs
, ctxt
->gs
);
122 loadsegment(ss
, ctxt
->ss
);
127 if (boot_cpu_has(X86_FEATURE_SEP
))
131 * restore XCR0 for xsave capable cpu's.
134 xsetbv(XCR_XFEATURE_ENABLED_MASK
, pcntxt_mask
);
136 fix_processor_context();
139 mcheck_init(&boot_cpu_data
);
142 /* Needed by apm.c */
143 void restore_processor_state(void)
145 __restore_processor_state(&saved_context
);
147 EXPORT_SYMBOL(restore_processor_state
);